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* GB785819 (A) Description: GB785819 (A) ? 1957-11-06 Stabilized solutions of hydrocortisone Description of GB785819 (A) Translate this text into Tooltip [75][(1)__Select language] Translate this text into The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes. PATENT SPECIFICATION 7 Date of Application and filing Complete Specification: Oct 6, 1955. B No 28536155. Application made in United States of America on Oct 18, 1954. Complete Specification Published: Nov 6, 1957. Index at acceptance:-Class 81 ( 1), B 2 (C: E: G: L: Z). International Classification:-A 61 k. COMPLETE SPECIFICATION Stabilized Solutions of Hydrocortisone We, MERCK & Co, INC, a corporation duly organized and existing under the laws of the State of New Jersey, United States of America, of Rahway, State of New Jersey,

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* GB785819 (A)

Description: GB785819 (A) ? 1957-11-06

Stabilized solutions of hydrocortisone

Description of GB785819 (A) Translate this text into Tooltip

[75][(1)__Select language] Translate this text into

The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION 7 Date of Application and filing Complete Specification: Oct 6, 1955. B No 28536155. Application made in United States of America on Oct 18, 1954. Complete Specification Published: Nov 6, 1957. Index at acceptance:-Class 81 ( 1), B 2 (C: E: G: L: Z). International Classification:-A 61 k. COMPLETE SPECIFICATION Stabilized Solutions of Hydrocortisone We, MERCK & Co, INC, a corporation duly organized and existing under the laws of the State of New Jersey, United States of America, of Rahway, State of New Jersey, United States, of Americasj do, hereby declare the invention, for which we pray that a patent may be granted to' us, and the method by which it is to be performed, to' be particularly described in and by the following statement:- This invention is concerned with preparations containing, as the effective ingredient, hydrocortisone ( 4-pregnene-11,,17 a,21-triol3,20-dione). Prior to the present invention it was. impossible to' prepare stable liquid preparations containing, high concentrations of hydrocortisone. The lack of solubility of hydrocortisone in the liquids usually

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employed for injection have given rise to various efforts and expedients for introducing hydrocortisone into the body Resort has, most commonly been had to) the use of suspensions of hydrocortisone, in either an aqueous or an oily vehicle, but none of these has proved satisfactory The amount of hydrocortisone that can be suspended in the liquid is quite limited, and the use of such suspensions is therefore not satisfactory when large concentrations are desired The preplaration of such suspensions under sterile conditions presented many imposing problems. Moreover in an aqueous suspension, the hydrocortisone is in the solid condition and its absorption int the; bloodstream by way of the aqueous; medium is slow and the rate of absorption is difficult to control These suspensions, furthermore, ha'd a tendency to discolour, cake or form a sediment during storage, and they had to be resuspended by shaking before use. Many efforts have been made to prepare derivatives of hydrocortisone that might be more soluble, but without sucoess Various fatty acid esters; of hydrocortisone have been prepared in an attempt to increase solubility of this steroid in oil Some of these derivatives, especially the lauric acid ester of hydrolPrice 3 s 6 d l cortisone, were more soluble in oil than hydrocortisone or hydromortisone acetate, but exhibited much lower biological activity than the acetate ester of hydrocortisone. The solutions of hydrocortis ona with which this invention isi concerned are useful in parenteral therapy in cases of medical crises where a quick-acting form of hydrocoridsone is required These solutions, of hydrocortisone are also useful in the treatiment of dermatologic afflictions such as various types of dermatitis, acute sunburn, poison ivy, poison oak, eczema, atopic dermatitis, and allergies. This invention is based on the discovery that the concentration of hydrocortisone in a liquid can be very considerably increased by adding ethyl alcohol to the hydrocortisone. Accordingly, this invention provides compositions containing from 5 to 20 ml of ethyl alcohol to approximately every 100 mig of hydrocortisone. A buffering agent such as sodium citrate may be employed in this composition, but it is not essential It has also been found that an antioxidant such as sodium bisulphlite may be added toi this, composition in order to, prevent discoloration of the preparationl on, pro:longed storage at elevated temperatures. The product of this invention is particularly adapted for intravenous use when diluted with sterile dextrose solutions A solution suitable for intravenous injection L, by the slow drip' method, comprises

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approximately 100 rng of hydrocotisone, 5 to 20 ml of ethyl alcohol, and 400 cc of aqueous dextrose solution. The following examples are given to illustrate typical aqueous solutions of hydrocortisone, suitable for intravenous injection by the slow drip method These examples are given by way of illustration and not of limitation. EXAMPLE 1 A concentrated aqueous solution of hydrocortisone containing the following ingredients was prepared, as described below: r 851819 Hydrocortisone 100 00 m- of the pyrogen-free distilled water was added Ethyl alcohol 10 52 cc to the mixture to make 20 cc of infusion Sodium, citrate dihydrate 8 00 mg concentrate of hydrocortisone. Pyrogen-free distilled water The concentrate of hydrocortisone was a S to make 20 00 cc clear, colourless solution devoid of any precitated material. mg of hydrocortisone was added to This infusion concentrate of hydrocortisone 10.52 cc of ethyl alcohol and the mixture was is not administered directly, but is added to warmed to 50 C whereupon the hydro 500 cc of sterile dextrose solution at the time cortisone dissolved in solution of usz, and the resulting infusion solution is 8 O mg of sodium citrate was dissolved in administered intravenously. approximately 6 cc of pyrogen-free distilled The following table summarizes the obserwater vations made on samples of infusion concenThe alcoholic solution of hydrocortisone trates of hydrocortisonc prepared as described was added to the aqueous; sodium citrate solu above: tion and the mixture stirred The remainder TABLE 1 INFUSION CONCENTRATE OF HYDROCORTISONE Hydrocortisone ( 100 mg /20 cc) Temperature Apparent Ethanol p H Time Colour Initial 92 4 53 2 % 7 25 500 C 2 wks 1 400 C 1 mo 7 05 1 500 C 1 mo 6 50 2 C 2 mos 98 7 35 400 C 2 mos 85 (-8 %) 6 65 1 C 2 mos 77 (-16 %) 6 45 2 C 3 mos 92 7 21 400 C 3 mos 80 (-13 %) 7 20 1 500 C 3 mos 70 (-24 %) 7 06 2 Code: 1 Slight, not objectionable 2 Moderate, possibly objectionable + Blue tetrazolium colour test An additional experimental lot containing ity The following is a mg of hydrocortisone per 10 cc of 78 5 % obtained. ethyl alcohol has also been studied for stabilsummary of the data 35 785,819 785,819 TABLE 2 INFUSION CONCENTRATE OF HYDROCORTISONE Hydrocortisone ( 100 mg /10 cc) B.T Ethanol Apparent p H Colour Clarity 95.7 mg 78 5 % 2 wks. 2 wks. C 1 mo. 400 C 1 mo. 500 C 1 mo.

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C 2 mos 99 400 C 2 mos 94 (-2 %) 500 C 2 mos 86 (-10 %) C 3 mos 94 (-2 %) 400 C 3 mos 87 (-9 %) 500 C 3 mos 80 (-16 %) The p H measurements reported in these A mixture of 100 mg of hydrocortisone tables were taken on the solutions directly was added to 10 52 cc of ethyl alcohol and Because of the high alcohol concentration it the reaction mixture was warmed to 500 C. is recommendeld that 1:25 dilution in water whereupon the hydrocortisone dissolved. be used for this purpose The alcoholic solution of hydrocortisone EXAMPLE 2 was added to 6 cc of pyrogen-free distilled A dilute aqueous; solution of hydrocortisone water with stirring The remainder of the containing the following ingredients was pre pyrogen-free distilled water was added to pared as described below: male 20 cc of infusion concentrate of hydrocortisone. Hydrocortisone O 11 gin This concentrate of hydrocortisone was a Ethyl alcohol 5 26 cc clear colourless solution devoid of any preciDextrose, reagent anhydrous 22 80 gws pitated material, and had satisfactory stability Pyrogen-free distilled water 500 00 cc characteristics.

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* GB785820 (A)

Description: GB785820 (A) ? 1957-11-06

Chrominance circuit for colour television receiver

Description of GB785820 (A)

PATENT SPECIFICATION 785,820 Date of Application and filing Complete Specification: October 28, 1955. No 30892/55 Application made in United States of America on November

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29, 1954 Complete Specification Published: November 6, 1957 Index at acceptance:-j Class 40 ( 5), W 4 A 5. International Classification:-HO 3 f. COMPLETE SPECIFICATION Chrominance Circuit for Colour Television Receiver We, STANDARD TELEPHONES AND CABLES LIMITED, a British Company, of Connaught House, 63 Aldwych, London, W C 2, England, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to a chrominance circuit for a colour television receiver, and more particularly to chrominance circuitry adapted to provide colourdifference signals for direct utilisation by a conventional picture tube. Conventional colour television receivers utilise in the reproduction of colour images two channels commonly characterised as luminance and chrominance channels The luminance channel carries the monochrome picture information which, for all practical purposes, may be considered to be substantially the same as the conventional black and white picture signal The chrominance signal branches off the luminance channel and by means of suitable band-pass circuitry extracts the chrominance signal information from the composite luminance signal and utilises this information for producing the usual colour-difference signals These colourdifference signals are applied to the picture tube in combination with the luminance signals to obtain proper colour reproduction A full explanation of the conventional colour television standards and of symbols and terms are found in the " Proceedings of the I R E " of January, 1954. The chrominance signal information is extracted from a band of frequencies which is approximately 1 0 megacycle in width, this band being centred about a subcarrier frequency of approximately 3 6 megacycles. This band of chrominance frequencies is demodulated, and it is both desirable and necessary, under the present NTSC colour television system, that the demodulating and amplifying circuitry have a " low-pass" lPrice 3 s 6 d l characteristic approximately 0 5 megacycle wide The reasons for this 0 5 megacycle band width are well understood by persons skilled in the art 50 ' In order to obtain the best efficiency in reproducing the colour signals, it is necessary that the frequency response of the demodulator and succeeding amplifiers be linear or flat under this 0 5 megacycle band width 55 In order to achieve this linear frequency response, prior art receivers utilise complex networks in almost every stage of the chrominance circuitry to limit the frequency response to a 0 5 megacycle band width, 60 and to

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maintain this frequency response flat. Thus, at almost any point in such chrominance circuitry, the band width response is linear The complex networks utilised to achieve this consistent and uniform fre 65 quency response are, of course, expensive and difficult to adjust Such complex networks obviously lead to major servicing problems. In accordance with the provisions of this 70 invention, these prior art complex networks have been entirely eliminated, as well as the necessity for flat response characteristics throughout the chrominance circuitry A substantial economy and reliability of opera 75 tion are achieved as well as a realisation of reduced cost. Instead of maintaining the frequency response of the chrominance circuitry throughout its extent flat for the selected 8 o band width of 0 5 megacycle, this invention comprehends the use of non-linear frequency response for the selected band width and the compensation for such non-linearity in the final stages While the frequency response 85 is non-linear at any given point in the chrominance circuitry, it is linear in the output circuit which is coupled to the picture tube. It is an object of this invention to provide 90 chrominance circuitry for a colour television receiver which possesses an overall linear 785,820 frequency response for a given band width. It is another object of this invention to provide chrominance circuitry for a colour television receiver wherein the frequency S response of component circuits or stages is non-linear, with such non-linearity of the various circuits being in a direction to comPlement each other whereby the overall frequency response is linear. For a better understanding of the invention, together with other and further objects thereof, reference is made to the following description taken in connection with the accompanying drawings, the scope of the invention being defined by the appended claims. In the drawings: Fig 1 is a block diagram of this invention; Fig 2 is a schematic diagram; and Fig 3 is an illustration of wave forms used in explaining the operation of this invention. Referring to the drawings, and more particularly to Fig 1, the luminance and chrominance channels are indicated generally by the reference numerals 1 and 2 The split between the two channels is conventionally made, for example, in the second detector stage of the luminance channel The chrominance signal information occurring about the centre subcarrier frequency of 3 6 megacycles is coupled to the usual chroma amplifier 3 and is fed to the usual demodulator circuits 4 The colour synchronising signals, commonly characterised as the "

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colour burst," is utilised by a " colour burst" gating circuit and synchronous local oscillator, indicated generally by the reference numeral 5, to control the operation of the demodulator circuits 4 The demodulated signal is then applied to the chrominance amplifier 6 for amplification, and then directly to the electron guns of the conventional tri-gun picture tube 7 The luminance circuits 8, which provide the usual monochrome signals, are also coupled to the picture tube 7 in a conventional manner. In order to obtain the best fidelity possible in reproducing colours, it is essential that the frequency response of the chrominance channel 2 be substantially fiat over a band from zero ( 0) to 0 5 megacycle This does not mean that this flatness of response is necessary at every intermediate point in channel 2, but that this response be present in the overall channel Explained in other words, measuring the frequency response of channel 2 in the output circuit of the amplifier 6 with a sweep frequency applied to the input of the chroma amplifier 3, this freQ quency response should be flat. A better understanding of this requirement is obtained by reference to Fig 3 wherein the frequency response of the chroma amplifier at point "A" is indicated by graph "A " It will be noted that this frequency response is non-linear over a band width of approximately 1 0 megacycle centred at about a 3 6 megacycle carrier. The response at point "B" (Fig 1) after demodulation is illustrated by graph "B" 70 (Fig 3), and it will be noted that the nonlinearity has been accentuated The frequency response of the amplifier 6 as a component circuit is illustrated by the graph "C" and it will be noted that this frequency 75 response drops ofr in such a direction that when the two graphs "B" and "C" are added, the substantially fiat or linear response of graph "D" is achieved The point at which the response characteristic 80 of graph "D" is obtained is indicated by the reference letter "D" in Figs 1 and 2. With reference to Fig 2, the chrominance circuitry includes the usual chroma amplifier 9 having the control grid coupled to the out 85 put circuit of the second detector in the luminance channel The amplified chroma signal is coupled to a band-pass coupler, indicated generally by the reference numeral 10, comprising primary and secondary wind 90 ings 11 and 12 tuned respectively by the usual slugs 13 and 14 This transformer 10 is so arranged that by adjusting the slugs 13 and 14 the degree of coupling between windings 11 and 12 may be varied to achieve 95 the desired non-linear band-pass characteristic The exemplary characteristic illustrated by graph "A" of Fig 3 shows the centre portion slightly depressed Even though this characteristic is not linear or 100 fiat, it may be utilised to advantage in achieving the necessary operating characteristics of the succeeding circuitry.

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To the output circuit of the coupler 10 is connected the usual "colour burst" gating 105 circuitry and local synchronous oscillator indicated by the block 15 Also connected to the coupler 10 is a suitable potentiometer 16 having the variable tap 17 directly connected to the control grids 18 and 19 of two 110 demodulator tubes 20 and 21 respectively. These demodulator tubes are provided with second control grids 22 and 23, respectively, to which are connected the circuitry of the block 15 A suitable phase shifting network 115 24 is interconnected between the two grids 22 and 23 for shifting the phase of the local oscillator sinewave applied thereto by ninety degrees ( 90 ). This is conventional practice in commer 120 cial television receivers Series connected in the plate circuit of the tube 20 is a combination peaking and carrier-filtering network composed of a resonant inductor and two resistors 26 and 27 which are 125 connected together at the lower ends A source of plate voltage is applied to these resistors as illustrated whereby they serve as the usual plate load resistors The inductor is designed to resonate at a frequency of 130 785,820 approximately 3 6 megacycles and further to peak the frequency response of the preceding circuitry as indicated by the reference numeral 28 of graph "B" (Fig 3) The D importance of this combination filtering action and peaking in frequency response will be explained more fully hereinafter A signal amplifier of conventional design, indicated by the reference numeral 29, is coupled by means of capacitor 30 to the peaking network 25, 26, 27 and is designed to provide a limited frequency response characteristic of the shape illustrated by graph "C" of Fig 3 It will be noted that J 5 this amplifier 29, while limited to a band width of 0 5 megacycle, falls off rapidly for the higher frequencies Comparing graphs " B " and "C," it will be seen that graph B " is peaked in the vicinity where graph go "C" drops off, such that the addition of these two graphs in order to determine the overall frequency response provides a substantially flat characteristic as illustrated by graph " D " Thus, by deliberately accentuating the non-linearity of the frequency response of the band-pass coupler 10 by means of the network 25, 26, 27, and being able to vary the degree of non-linearity by adjustment of the slugs 13 and 14, the _ O band-pass characteristic of the amplifier 29 may be matched or complemented to achieve the substantially flat response of graph " D " For purposes of convenience, the respecj 5 tive plate circuits of the demodulator tubes and 21 are characterised as colourdifference channels, and in the circuit of Fig 2 the channel indicated by the reference numeral 31 is the "-(R-Y)" channel and the channel 32 is the "-(B-Y)" channel. These formulas are used in the commonly understood sense, the letter

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"Y" denominating the luminance signals, the letter "R" red chrominance signals, and the letter "B" blue chrominance signals As is well known, the mathematical combination of the luminance and red, green and blue chrominance signals in a particular manner makes it possible to obtain the reproduction of selected colours -50 in the picture tube Thus, by use of the two demodulators 20 and 21 to -obtain the colour-difference signals of the two channels 31 and 32, it is possible to obtain from the combination thereof with the luminance S signal any one or combination of the three colours red, green and blue While the two demodulator circuits 20 and 21 have been illustrated, for all practical purposes, they may be considered as duplicates insofar as this invention is concerned, since the frequency response characteristics of the overall circuitry as measured between the chroma amplifier 9 and the outputs of the two amplifiers 29 and 33 is made substantially ,65 flat A description of the one demodulator circuit 20 and the associated amplifier 29 will suffice as a description of the demodulator 21 and its associated circuitry. In operation, the chrominance signals passed by the coupler 10 constantly vary in 70 amplitude and phase in accordance with conventional practice The "colour burst" signals synchronise the local oscillator 15 to provide a reference sinewave for the grids 22 and 23 of the demodulators 20 and 21, 75 respectively The chrominance signal appearing over the potentiometer 16 is coupled to the grids 18 and 19 and is demodulated in the usual manner to provide the rectified colour difference components in the two 80 channels 31 and 32, respectively These rectified components are amplified by the two signal amplifiers 29 and 33 which are in turn coupled to the receiver picture tube in the usual manner 85 Since the chrominance signal applied to the band-pass coupler 10 occurs about a carrier frequency of approximately 3 6 megacycles, it is essential that this carrier frequency be prevented from passing through 90 to the amplifiers 29 and 33 The peaking coils 25 and 34 are designed to present a high impedance to this carrier frequency to prevent it from being applied to the grids of the amplifiers 29 and 33, respectively 95 The amplifiers 29 and 33 are initially designed to provide as much gain as possible in a frequency range approximately 0 5 megacycle wide One practical circuit design of this invention resulted in a frequency 10 ( response of each amplifier being in the shape of graph "C" (Fig 3) By adjusting the slugs 13 and 14, the frequency response of the circuitry preceding the amplifiers 29 and 33 may be altered in a complementary 10 i S direction such that the overall frequency response will be flat, as represented by the graph "D " In achieving this frequency response, it is of importance that the peaking coils 25 and 34 serve to accentuate the,11 non-linearity of the characteristic of coupler 10, whereby a

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flat characteristic in the output of the two amplifiers 29 and 33 is more nearly achieved. The simplicity of the circuitry as con 11 trasted with former prior art arrangements is obvious Adjustment of the overall chrominance circuit response is achieved in a facile manner by merely adjusting the slugs 13 and 14 of the coupler 10 This 12 G simplicity sharply contrasts with the prior art designs wherein it was necessary to peak and shape the frequency response in almost every stage throughout the chrominance circuitry in order to achieve the desired end 125. result. While it will be understood that the circuit specifications of this invention may vary according to the design for any particular application, the following circuit specifica 13 G tions for suitable chrominance circuitry are included by way of example only: 785,820 Tubes 20 and 21 Inductors 25 and 34 Resistors 26 and 27 Tube 29 Tube 33 Choke 35 Condenser 30 Resistors 36 and 37 Resistors 38 and 39 Condensers 40 and 41 Condensers 42 and 43 6 BY 6 6 Millihenries 22,000 ohms 96 AN 8 12 BY 7 Microhenries 0.01 mfd. 1 Megohm 10,000 ohms Microfarads 1,500 Micromicrofarads Resistor 44 150 ohms Resistor 45 270 ohms While there has been described what is at present considered the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention.

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* GB785821 (A)

Description: GB785821 (A) ? 1957-11-06

Improvements in paper and like bags

Description of GB785821 (A)

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COMPLETE SPECIFICATION Improvements in Paper and Like Bags I, MARIUS BERGEIGRACHT a Belgian sub ject, of 71 Forelstraat, Ghent, Belgium, do hereby declare the invention, for which s pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to improvements in flat bottom bags, of the type including an extensible side fold or the socalled "bellows" bags including the simple transverse seal at the bottom. Such bags are known and in common use but they have numerous disadvantages particularly as regards their lack of tightness, their poor appearance, and the impracticability of using them on automatic machines, e.g. packing machines. The present invention has for its object a bag of the type described which has numerous advantages among which should be mentioned in particular perfect tightness, perfect hermetic sealing of the seams and of the closure, the possibility of automatic opening of the mouth portion thereof permitting its use on automatic machines and finally the fact that the bag may be produced economically on normal bag making machines and that once folded and closed its appearance is that of a box which is a much more expensive form of package, various other advantages of the bag according to the invention will be apparent from the following description. The material utilised is either a sheet of paper or several sheets of paper or one or more sheets of paper and one or more sheets of another material such as alumi- mum, fabric, plastic material and so on. Whenever multi-plies are used the assembly is preferably of laminated form the plies being adhered one to the other by means of thermoplastic lacquers and at least one face, namely in the case of one face only that forming the inside of the bag, is covered or otherwise coated with a thermoplast;c lacquer. Thus a cheap workable material is obtained which can be utilised readily on machines for making flat bottom bags having side folds but having the great advantage of being absolutely tight and impermeable, adapted for hot sealing and particularly having a composition which can receive and preserve the fold lines which is not possible with the ordinary paper utilised heretofore for the production of bags of this type. These fold or crease lines which are suitably positioned, permit ready opening of the bag and since such fold or crease lines maintain their correctness by reason of the composition of the material used, when the bag is filled and closed, the package presents the appearance of a

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box although it is in fact comprised by a bag of the character described which is in fact the simplest and cheapest package to produce. Bags are already known embodying tucks or folds which when filled and closed have approximately the appearance of a box but in the present invention a bag with side tucks and folds is concerned having i square bottom as opposed to the ordinary flat bag the bottom of which is formed by transversely sealing the tube, one end of which is simply folded perpendicularly to the longitudinal axis of the tube; while bags with a square bottom have heretofore been produced from a tube one end of which is folded several times about different angles so as to form a base of polygonal section folded perpendicularly to the axis of the tube. Such bags are known but require much material, are complicated and costly to produce and moreover the numerous overlying folds at the bottom prevent obtaining even approximate tight ness of the bottom. On the contrary the bags forming the object of the present invention only require the minimum of material are very simple and economical to produce and are absolutely fluid tight. Embodiments of the invention are shown by way of example on the accompanying drawings in which: Fig. 1 shows in plan the blank from which a bag according to the present invention can be produced by folding. Fig. 2 is a plan view of a blank similar to that of Fig. 1 but provided with flaps facilitating the formation of the closing of the bottom. Figs. 3 and 4 show diagrammatically the construction of the seams and the sealing of the bottom of the bag. Fig. 5 is a partial v;ew of a sealed bottom. Fig. 6 is a perspective view of a bag the bottom closure of which is in course of formation. Fig. 7 shows the packet produced after folding and sealing, and Fig. 8 shows an upper part of a packet in perspective designed particularly for vacuum conditioning and sealing. The bag according to the invention may be produced from a flat blank 1 as shown in Fig. 1 or from a continuous tube to which similar score lines are applied. This blank is comprised by a comparatively rigid sheet formed by a single layer or by a multi-ply sheet as explained above; the face which is to form the interior of the bag is covered with a layer of thermoplastic lacquer which may be treated if necessary so as to be aseptic. This assures perfect impermeability and moreover gives the necessary properties e.g. of stiffness to permit it to receive and preserve fold or crease lines where necessary for the formation of the bag. Highly satisfactory results are obtained if the

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thermoplastic lacquer is interposed between two sheets of paper from which the blank is formed. This blank is intended for the formation of a fiat bottom bag embodying side folds i.e., the so-called "bellows" bag and it mav be preformed by scoring or the like with two groups of fold lines each comprising three vertical crease lines 2, 3, 4 and 2', 3' and 4' intended to form the lateral folds or tucks. Two other fold or crease lines are provided each comprising two horizontal fold or score lines 5, 6 and 5' and 6'; the former pair 5, 6 being situated at the base of the blank and providing for the formation of the bottom and the other fold or score lines 5' and 6' being located at the upper part of the blank and comprising the folds for the formation of the closure. Moreover at the base of the two groups of vertical fold lines 2, 3, 4 and 2', 3' and 4' at the point where they meet the horizontal fold lines 6 further fold lines 7 and 7' are provided forming a right angle triangle having the line 6 as its base and the apex of which is directed towards the base of the blank at a right angle, which facilitates the formation in that the parts of the score lines 6 between the lines 2 and 4 and 2' and 4' come into line and the fold lines 7, 7' form inward tucks of triangular shape which overlie parts of the side walls (i.e. between lines 4, 4' and 2, 2') lying between the lines 5 and 6 when the appropriate parts of the side walls are folded to form the bottom of the flat bottom for the bag and facilitates the opening of the bag below the folds or tucks. In the modification shown in Fig. 2 the blank 101 is provided at its lower part with a flap 8 traversed by a horizontal fold line 9 situated in line with the lower edge of the blank, and at its upper part with a flap 10 which is considerably longer than the flaps at present utilised in packet manufacture. This flap is in the form of a symmetrical trapezoid of which the larger base coincides with the folding line 11 situated in line with the upper edge of the blank 101. Figs. 3 and 4 show the method of gum. minx, sealing and reinforcing the seams ;f the bag. The blank 1 or 101 is folded along its vertical fold lines in such a way that the lateral edges thereof are joined together so as to form the second large side of the bag. At the overlapping point these edges are fixed one to the other either by means of a line of adhesive 12 and one hot sealing surface 13 (see Fig. 4) or by means of one hot sealing surface 13 disposed between two lines of adhesive 12 (Fig. 3). As regards the bottom of the bag and after having completed and welded the seams as explained above, the bag is first seated as far as the

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level of the horizontal fold line 5, then folded on itself and sealed to or welded to the outside of the part between lines 5 and 6. The thickened part 14 thus obtained may be again folded, welded or stuck down (see Fig. 5). This bottom construction is simple to produce owing to its similarity to the methods usable in the case of the ordinary flat bag without side folds. By reason of the arrangement of the fold lines the bag has, when open, a square or rectangular form which gives it the appearance of a box. Moreover the said fold lines facilitate the immediate and easy opening of the bag during use. Fig. 6 shows the form of bottom closure obtained in this way as well as bag constructed by means of the blanks shown m Fig. 2. The vertical fold or crease lines of the lateral tucks or folds, combine with the triangular fold lines 6-7, 6-7' at the base thereof and with the thickened portion at the base of the package to form a tuck, whereby automatic and immediate forma- tion of a fiat rectangular bottom with sharp angles is obtained. The upper flap 10 (see also Fig. 2) flanked by the side pieces 10' is folded down on to the upper edge of the package in a similar manner to that already de scribed, and the fold formation may be such as to form a horizontal thickened portion 15, Fig. 7, which is hot sealed with ;rl some cases the interposition of a complementary sealing surface which is capable of reinforcing the joint or weld in the samv: way as for the reinforcement of the lateral seam (see Figs. 3 and 4). Triangular sections 10' (which may if desired be trapezoidal) which flank the upper flap 10 cooperate during folding of the latter with the upper edges of the packet, which are likewise folded, ensuring perfect hermetic tightness of the folds and of the closure so formed. After closure the upper part of the packet completes the appearance of a box. A suitably shaped pierce of rigid material may be applied over the contents of the bag. When the bag is to be utilised for the vacuum conditioning of the materials which it contains the upper edge of its larger side opposite to that carrying the flap 10 (see Fig. 6) carries a row of small perforations 16. The materials being placed in the bag the upper edges of the packet are brought one towards the other and they are sealed in such a way that the perforations 16 remain free, that is to say that communication is left between the inside of the bag and the atmosphere. The packet thus prepared is then placed in a vacuum enclosure in the circuit of the filling machine, the evacuation is effected in the enclosure and in the packet, the valve 17 formed by the extension of the flap 10 and laid down over the row of perforations 16 is automatically drawn against the latter when the

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packet is released to atmospheric pressure. At this moment the parts of the flap 10 and of the valve 17 which cover the perforations 16 are hot sealed. The materials packed in this way are protected from all contact with the air and form a compact strictly hermetically sealed mass and the packet is completely sealed around them. For example a packet containing coffee grains and sealed under vacuum in the described manner offers good compactness and can be stored for a long period The bags according to the invention can be used for packing solid products in a neutral or light gaseous medium, for example nitrogen, hydrogen or helium. It should be noted that the vacuum con ditioning of perishable or other material could only be obtained heretofore by the use of wrappings comprised by a rigid and impermeable material such for example as glass, tin plate, aluminium or other similar materials. What I claim is: 1. An air tight flat bottom bag comprising a tubular body portion formed from a flexible material such as paper or a multi-ply material partially or completety covered or impregnated with a thermoplastic lacquer to provide properties such that pre-formed score lines permit ready folding and of the type having longitudinal score lines to form side bellows folds capable of being flattened, chacterised in that the body portion includes a transverse score line extending across the tubular blank and a simple transverse bottom seal extending across one end of the body, said seal being so positioned in relation to said transverse score line that automatic erection of said body to form a flat-bottomed bag is obtainable by an opening movement which causes the two sections of the said transverse score line which lie one over the other before erection at each side fold, to move into line, with the formation of an inwardly directed tuck defined by said sections of the score line and by oblique fold lines running inwardly from each corner of the bottom seal and meeting the longitudinal score lines centrally of the bellows folds. 2. A bag according to claim 1 characterised in that it is produced from paper consisting of a single layer of strong, impregnated paper covered with a thernio- plastic lacquer adapted to be hot sealed. 3. A bag according to claim 2 characterised in that it is produced from a cut blank comprising a multi-ply construction consisting of two sheets of paper assembled by means of a thermoplastic material and of which the face intended to form the inner wall of the wrapping is covered with a hot sealing thermoplastic lacquer. 4. A bag according to claim 2 characterised in that it is produced from a cut blank from a multi-ply material consisting of a sheet of paper and a sheet or several sheets of a solid opaque material

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assemblers one to the other by means of a thermo. plastic lacquer and of which the face intended to form the inner wall of the wrapping is covered with a hot sealing lacquer. 5. A bag according to claim 2 characterised in that it is produced from a cut blank of multi-ply construction comprised of several sheets of paper and one or several sheets of solid opaque material assembled by means of a thermoplastic material and of which the face intended to form the inner wall and in some cases the outer wall of the wrapping is covered with

* GB785822 (A)

Description: GB785822 (A) ? 1957-11-06

Improvements in paper and like bags and machines for producing them

Description of GB785822 (A)

PATENT SPECIFICATION 78 o 598:22 Date of Application and filing Complete Specification May 12, 1953. No.38671/56. Application made in Belgium on May 12, 1952. (Divided out of No 785,821). Complete Specification Published Nov 6,1957. Index at acceptance: -Class 94 ( 2), D( 1 B: 2 81: 4 C: 4 M), E 2 (G 5: K 3: K 4: M). International Classification: -331 b B 65 d. COMPLETE SPECIFICATION Improvements in Paper and like Bags and Machines, for producing them I, MARIUS BERGHGRACHT, a Belgian Subject, of 71, Forelstraat, Ghent, Belgium, do hereby declare the invention, for which I pray that a patent may be granted to me and the method by which it is to be performed, to be particularly described in and by the following statement: - The present invention relates to machines for producing tubular blanks from which flat bottom bags of the type having an extensible side fold, i e, the so-called " bellows " bags, can be produced; and the

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invention further relates to improved bags produced by means of such blanks. One object of the present invention is to provide an improved machine whereby such blanks may be expeditiously produced and whereby blanks are obtained which permit improved types of bags to be produced A further object is to provide improved types of bags produced from such blanks. The material used for the formation of the blanks is either a sheet of paper or several sheets of paper or one or more sheets of paper and one or more sheets of another material such as aluminium fabric, plastic material and so on Whenever multiplies are used the assembly is preferably of laminated form the plies being adhered one to the other by means of thermoplastic lacquers and at least one face, namely that forming the inside of the bag, is covered or otherwise coated with a thermoplastic lacquer. Thus a cheap workable material is obtained which can be readily worked on bag making machines but having the great advantage of being absolutely tight and impermeable, adapted for hot sealing and particularly having a composition which can receive and preserve the fold lines These fold or crease lines which are suitably positioned, permit ready opening of the bag and since such fold or crease lines maintain their correctness by reason of the composition of the material used, when the bag is fielled and closed, the package presents lPrice 3, 6 d ' the appearance of a box although it is in fact comprised by a bag of the character described which is in fact the simplest and cheapest package to produce. The machine according to the present 50 invention is characterised in that a mandrel provided with a sealing device forms an endless tube of the same section as the mandrel from a strip of paper or other like material fed from a reel, the tube seam being disposed 55 at any predetermined point on one side of the tube and being sealed down, and laterally extensible folds are thereafter produced in the sides contiguous to the seamed side on an extension of the mandrel in the form of a 60 tapered forward part, such formation of the folds being effected by means of Dresser rollers carried by inclined arms, to form a continuous flattened tube with lateral bellows folds, said tube being thereafter cut to length 65 and sealed at one end by a simple transverse seal The sealing device is preferably located at a marginal part of the mandrel so as to produce a seam adjacent to one of the said contiguous sides 70 Tubular blanks produced as described or bags or packages produced therefrom, may be of square transverse section and the opposite extremities of the bellows folds thus come into contact one with the other when the bag 75 or package or the tubular blank is flattened; this arrangement is advantageous as a uniform

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thickness is provided when the bottom closure of the package is being performed by means of a simple transverse sealing operation 80 Further, the longitudinal seam in the blank may be arranged non-centally of one of the lateral faces of the blank not provided with folds and this arrangement also facilitates the formation of kthe transverse bottom sealing 85 since the seam does not coincide with the tips of the folds when the blank is flattened. The features of the Dresent invention are shown by way of example on the accompanying drawings, wherein: 90 4 4 785,822 Figs 1 to 3 show diagramnatically a known type of machine for nroducing tubular blanks with side bellows folds from which bags or packages can be formed, Fig 1 being a side view, Fig 2 a plan view and Fig 3 a section on the line XVII-XVII of Fig 1. Figs 4 to 6 show the details of an improved machine according to the present invention, Fig 4 being a side view, Fig 5 a plan view and Fig 6 a section on the line XX-XX of Fig 4. Fig 7 is a perspective view of the top of a packet showing the form and position of a top closure of a bag, but showing a side seam according to the present normal method, this figure should be compared with Fig 12 showing an improved bag according to one feature of the invention. Figs 8 and 10 are plan views showing a bag with extensible folds before hot sealing and being respectively a view showing the present normal arrangement and a view showing a further feature of the invention. Figs 9 and 11 show the same bags respectively during hot sealing. Fig 12 is a view similar to Fig 7 showing the preferred location of the seam, and Figs 13 and 14 are sections respectively on the line XIII-XIII of Fig 7 and XIV-XIV of Fig 12 showing the two forms of bag during the course of sealing. Figs 1 to 3 illustrate known types of machines for producing tubular blanks with side bellows from which bags or packages can be produced after severing lengths from the tubular product leaving the machine, which lengths are transversely sealed at one end and fold lines formed whereby a flat bottom may be produced of the character shown for example in Specification No ( 13267/53) (Serial No 785,821). The paper or other like material of single or multi-ply type from which the bag is formed, is fed from a reel 116 and passes between the guide rollers 117, 118 The paper arriving below the guide 114 ' is folded upwardly by the guide fingers 119 which lay the paper against the guide 114 where it is held by the rollers 120. The arms 121 provided with rollers 122 initiate the folding of the extensible tucks which are formed progressively as the paper advances on the guides The rollers 122 press the paper against the guides

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114-114 o until the assembly is quite tight between the guides and the rollers This stage is obtained when the extensible folds are practically finished and folded towards the inside At this moment the two guides have reached a position very close one to the other as illustrated in Fig 1 When the paper is perfectly tight and when the two edges are placed lightly one against the other at 123 a suitable device seals the two edges one against the other. The sealing device is generally comprised by a heating roller 124 on the guide 114 and two small rollers 125, 1251 providing counter pressure below the guide for the heating roller 124. The rollers 125 and 125 ' should have a 70 width at least equal to the width of the sealing band and since these rollers must be supported it is necessary to provide sufficient space in the machine for accommodation. As has been indicated above, as sealing can 75 only be effected when the extensible folds are practically complete, there always remains between the extremities of the folds a space of the order of 11 cm It will be explained below that it is highly advantageous in the case of 80 bags with extensible folds for the folds to touch one another within the closure as shown in Figs 10 and 11, which is impossible to obtain with present machines. Another disadvantage of present machines 85 results from the fact that immediately after sealing the tube is driven by rollers 126 which press on the tube so formed, and then the tube is cut When the hot sealing is to be effected the thermoplastic material is then 90 still slightly plastic and it often occurs, particularly for high production speeds, that the bags are sealed internally along the seam while passing between the driving rollers 126. Finally the present machines do not permit 95 heat-sealing the tube along the extreme edge of a side for it is not possible to maintain the two ends to be sealed one against the other in the overlapping sealing zone when this zone is near one of the edges of the guide 100 On the other hand, there is practically no space below the guide 114 for housing the rollers 125, 1251 On Fig 3 there is shown diagrammatically a section on the line XVII-XVII of Fig 1 It will be seen that 105 it is impossible to locate the rollers 125 and 1251 nearer the edges and it is for this reason that at present the seam is always at the centre Hence it has not heretofore been possible to produce heat-sealed bags of square 110 section with extensible folds and with an ordinary bottom nor to produce heat-sealed bags with extensible folds and with an ordinary bottom and with a seam towards the edge of a side nor to produce square bags with 115 an ordinary bottom and a seam along the edge of a side. The present invention comprises the provision of -a machine for

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producing paper bags with extensible folds directed towards the in 120 side and with an ordinary bottom permitting bags to be produced of any section, for example square, and to produce them while providing a longitudinal seam in a side which is not folded, for example on one of the edges 125 of one 'lace not comprising the extensible folds. The machine forming the object of the present invention is shown in Figs 4 to 6 and comprises essentially a mandrel of any section, 130 785,822 for example square, 127 The paper strip 128 fed from a reel 129 passes between feed rollers 130 and is placed around the mandrel 127 by means of folders 131 or any other similar manner as in the known machines The mandrel 127, the length of which is about 1 m., is thus covered with a layer of material intended for the formation of the bag The two edges of the sheet 128 overlap to an extent corresponding to the width of the seam which it is desired to produce This seam may be obtained in any desired way, the rollers 132, 133 maintaining the sheet under tension and in place which permits perfect sealing by means of a heating and presser roller 134 The pressure exerted by this roller 134 is balanced by the counter pressure exerted by two small rollers 135 located within the mandrel 127, a window space being cut therein at this point If desired, a preheating device 136 is arranged along the seam to be produced just in front of the roller 134. Beyond the sealing roller 134 there is located in line therewith and along the seam, a series of rollers 137, 137 ', the former arranged above the seam and the latter substantially below the upper face of the mandrel, these latter being intended to ensure the pressing of the seam to obtain perfect sealing The resulting tube has the same section as the mandrel A roller 144 urges the bottom of the tube along the bottom of the mandrel. The tube, which is perfectly sealed, is provided with laterally extensible folds which are produced on the two opposite sides in the following very simple manner: the lateral vertical faces of the mandrel 127 are omitted after the last pair of rollers 137 and the two other faces of the mandrel approach one another so as to form a nozzle-like member as indicated in Fig 4 If desired, a spacer 139 maintains the two faces 138 and 1381 at the desired spacing. Rollers 140 arranged on arms 141 and 1411 are disposed between the faces 138 and 1381 of the mandrel The arms 141 and 141 ' are disposed obliquely relatively to the longitudinal direction of the mandrel in such a manner that the rollers 140 spaced along the length of the tube, approach progressively and in some cases may even cause the inner folds of the bellows to touch each other The folds of the extensible parts are thus perfectly marked and the extremities of the fold section just touch one another when the bag is flattened In

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general the final rollers 140 do not touch one another exactly but there is a small space between them which corresponds to the thicknesses of the two inward folds and which allow for the separation between the faces of the bag At the point corresponding to the final rollers, which should be very thin, the two faces 138 and 1381 are brought very close one to the other and practically touch The tube so formed, with the extensible sections folded towards the inside is driven by the cylinders 142 and a suitable device for example a guillotine 143 cuts tube sections of the desired length suitable for producing an extensible fold-bag 70 The advantages of the machine of Figs 4 to 6 follow from the position of the sealing device on the mandrel The arrangement produces a tube of any section which is then provided with extensible folds The positioning 75 of the sealing device on the mandrel ahead of all the rollers 140 permits the sealing device to be placed at any point equally at the extreme edge as at the centre On the other hand the distance between the sealing device 80 and th guillotine is such that complete cooling of the sealing zone is ensured, even for high feed speeds, however great these may be in practice Finally it is possible to produce tubes of any section and particularly for 85 example of square section By the fact that the sealing device is placed ahead of the rollers it is possible to produce extensible folded' sections which touch one another perfectly when the bag is folded with the folds towards 90 the inside. As above indicated, the machine shown on Figs 4 to 6 permits tubular blanks to be produced each of square cross-secion when opened out and/or each provided with an off 95 centre longitudinal seam on one of the sides not embodying the bellows folds Heretofore, bags with extensible folds have had a rectangular but not square cross-section and in this case it has been found that the extensible 100 folds, folded towards the interior, offer excess thickness which during hot sealing by means of thermoplastic materials prevent perfect tightness being obtained. Figs 8 to 11 of the accompanying drawings 105 are sectional or plan views from above of a bag with extensible folds, Figs 8 and 10 being before hot sealing and Figs 9 and 11 after sealing Figs 8 and 9 refer to the known methods while Figs 10 and 11 represent sub 110 sidiary features of the invention. It will be understood that after hot sealing small non-sealed openings 18 and 19 (see Fig. 9) are unavoidably formed In general, and as shown, the outer sheet of paper or other 115 material 20 is covered internally by a layer of thermoplastic material 21 The jaws 22 and 23 which bear against the surfaces to be sealed and press them one against the other ensure perfect sealing of the parts 24, 25, 26 and 27 120 If the distance

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between the ends of the extensible folds is relatively great and especially if the operative surface of the jaws 22 and 23 is flexible or is appropriately shaped the parts 28 are applied one against the other 125 despite the excess thickness of the extensible folds, but in all cases there always remains the spaces 18 and 19 which the thicker the paper are not closed since the parts which are to be sealed are not brought into contact 130 4 785,822 To avoid this disadvantage which is very serious in the case of air-tight wrappings effected under vacuum or under gas pressure, the extensible fold-bags produced by blanks formed by the machine of Figs 4 to 6 are preferably of square section so that the tips of the extensible folds come into contact during the bottom formation of the package as illustrated in Figs 10 and 11. The layers of thermoplastic materials 21 ' which cover internally the faces of the bag and of the extensible folds, come into intimate contact throughout and when the gripper or jaws 221 or 231 are applied to the package, although the thermoplastic material is fluid, there is an intimate fusion or welding of the whole thermoplastic mass and as there is excess thickness at no point there is no need to give the grippers or jaws any special form and there is no risk of having a leak in the closure, which is in fact perfectly tight. Further the longitudinal seam of the bag has heretofore been placed nearly at the centre of one of the side faces of the bag namely the side not having the extensible lfolds as is illustrated in Fig 7 The bag 29 is provided all along one of its faces with a seam 30 shown in dotted lines At this Point there are two thicknesses of material superposed one on the other. Fig 13 shows in section on the line X If I-XIII of Fig 7 the arrangement of the various layers in contact during the sealing of the closure of such a bag 20 shows the material of the bag, for example paper, and 21 shows the layer of thermoplastic material intended for the hot sealing of the closure. In the zone 30 there is an excess thickness and the clamping grippers cannot provide perfect sealing since this excess thickness acting at the centre of the active surface of the gripper, acts just at the joint where the pressure is the least; by reason of this excess thickness there are no means for powerfully clamping the two longitudinal edges. If, in the case of an extensible fold bag, the position of the seam at the centre coincides with the tips of the folds which do not come into close contact one with the other, the difficulties due to the fact that the bags are rectangular and have a central seam are added and it becomes practically impossible to obtain a perfectly tight sealing Finally the central position of the seam in the middle of one face of

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the bag prevents obtaining printing on the two flat faces of the bags Generally it is desirable to incorporate publicity or Trade Mark material and it has been necessary to divide such printing into two sections on the two sides of the seam. Preferably, therefore, the longitudinal seam is arranged towards the edge of one face as shown in Fig 12, where the bag 29 ' is sealed longitudinally at 301 to the side of one of the side faces not provided with extensible folds. On Fig 14 there is shown diagramatically in section on the line XIV-XIV of Fig 12 the closure of the bag 291 The zone 301 is shifted to the side where it no longer adversely influences the sealing in the manner shown on 70 Fig 13 The action of the gripper or jaws is much more effective at the edge than at the centre and the operative closure point between the inner extremities of the extensible folds folded towards the inside, is outside of the 75 zone of excess thickness.

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* GB785823 (A)

Description: GB785823 (A) ? 1957-11-06

Improvements in or relating to the casting of ferrous metals in ingot moulds

Description of GB785823 (A) Translate this text into Tooltip

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The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in

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particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION 785,823 Date of Application and filing Complete Specification May 20, 1954. No 14856/54. Application made in France on May 23, 1953. Complete Specification Published Nov 6, 1957. Index at Acceptance:-Classes 83 ( 1), F 6 BX; and 95, A 9 (A: B: C). International Classification: -B 22 c CO 9 d. COMPLETE SPECIFICATION Improvements in or relating to the Casting of Ferrous Metals in Ingot Moulds I, HENRI JEAN DAUSSAN, of 9, rue de Verdun, Metz (Maselle), France, of French nationality, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to the casting of iron and its alloys (cast irons and steels) in ingot moulds. It is known that in the production of ingot, or castings having a shape similar to that of an ingot such as a rolling mill roll, known difficulties arise due to the impurities introduced by the stream of molten metal, or due to the refining impurities, or due to particles derived from the refractory materials of various apparatus for production or for transfer to the ingot mould. Other difficulties are due to the dynamic effect of the stream of metal and to the cooling of the metal bath up to its solidification point. Numerois defects, more especially the following, inl the ingots and other cast pieces result from these various difficulties: The bottom splashes due to the spreading wave caused at the beginning of the casting by the stream of metal; The shelliness due to the small side projections of metal coming from the bath or from the stream of metal while the ingot mould is being filled; Slag patches on the surface of the ingot on account of the clinging of the slag to the wall of the mould; Non-metallic inclusions and certain blow holes due to occluded gases coming from the impurities which have had time to separate during the solidification and which remain imprisoned in the ingot. In order to overcome these disadvantages, it has been proposed more particularly to coat the internal wall of the mould with tar, bitumen or other coatings derievd therefrom, cream of lime, graphite, silico-aluminous refractory earths or the like Deoxidizers, such as aluminium or ferro-silicon, have been added to these various

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substances. Numerous mixtures for coating purposes have already been proposed and many of said mixtures contain a certain amount of mixing water which may be water of addition, and/or water of crystallisation and/or constitution but said amount is sufficiently small to enable a complete drying of the applied coating before casting. Indeed, in order to conform to the customary recommendation regarding the application of a coating to the internal surface of an ingot mould wall, efforts have been made to obtain before casting a dry film of coating free from all trace of humidity, and producing no liberation of gas or vapour, at least when the level of the molten metal comes into contact with it. It has also been proposed to use coatings which, owing to the combustion gases which they contain, produce a slight peripheral turbulence In particular cardboard has been stuck on the ingot mould wall with starch paste to cause the said slight peripheral turbulence. It has also been proposed to use coating products containing boric acid or up to 2 % of borax, and also a coating product, intended for the pouring of magnesium and the alloys thereof, which contains 50 % of boric acid and 50 % of graphite. In short, in coating the internal surface of ingot mould walls it has hitherto been customary to avoid any trace of humidity remaining at the instant when the molten metal comes into contact with the coating, and also to avoid the simultaneous production of a great peripheral turbulence. All the known coatings or other means, whilst overcoming many disadvantages, are incapable of entirely avoiding non-metallic inclusions in dificult cases, for example in the bottom pouring of a steel of high viscosity. As regards bottom splashes, no coating has avoided them Effective devices called " shock 785,823 absorbers ", have, however, been provided which used in conjunction with coatings can avoid them. The invention relates to an iron and steel ingot casting method which makes it possible on the one hand to eliminate all non-metallic inclusions, even those in the heart of the ingot, far from the surface, and even in the most difficult cases of bottom pouring of high viscosity steels, and on the other hand, to avoid bottom splashes in the most difficult cases of top pouring. According to the invention, the internal surfaces of the ingot moulds are coated with a mixture comprising one or more carbonaceous substances, and at least one substance having sufficient water of crystallization and/or of constitution that the coating contains a portion of said water before casting, even when the coating has dried under the effect of the room temperature or of the temperature of

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about 60-80 C, of said mould following on a previous casting operation. During the pouring, the vapours and gases liberated by the substance or substances rich in water and also the gases obtained from the combustion of the carbonaceous substance or substances, create a strong inward thrust or pressure from the wall of the mould already submerged by the poured metal, this thrust being directed obliquely towards the centre and the upper part of the molten metal so that impurities are not blocked at the periphery of the ingot where the poured ingot commences to solidify. Advantogeously a mixture is used which comprises one or more carbonaceous substances, and borax and/or boric acid containing water of crystallization and/or of constitution in a proportion of from 4 % to 22 % by weight of the whole. Borax or boric acid or a mixture thereof make it possible to obtain the formation of steam or gases from the water of constitution and/or of crystallization at well-defined temperatures which suit the molten ferrous metals and alloy. The properties of borax and boric acid are as follows: Borax, of the formula Na B,07 10 HD 0, contains by weight: 36.52 % of B 20, 16.25 % of Na O 47.23 % of water of crystallization. It is very stable at ordinary temperatures but it melts as soon as the temperature exceeds about 620 C, after which it loses its water of crystallization approximately as follows:H,0 up to 1300 C. 3 H,0 from 1300 to 1500 C. 2 H 1,0 from 1500 to 1800 C. 1 H,0 from 180 to 318 C. at which latter temperature anhydrous borax, Na B 407, is obtained, having a melting point of 741 C, but aqueous solutions of borax hydrolyze, yielding metaboric acid and then boric acid. Boric acid, having the formula HBO,, and containing 56 3 % of boric anhydride and 43.7 % of water of constitution, loses part of 70 its water beyond 120 C and is converted into metaboric acid Above this temperature, at about 230 C, it is converted into boric anhydrides, B O,, which when heated assumes a vitreous form melting at 450 C 75 into a vicous glass, the viscosity of which falls gradually in the wide temperature range of the molten metal, and at a red heat dissolves metal oxides. The behaviour according to the invention, of 50 borax and boric acid is substantially the same since under the action of the heat of the bath of molten metal borax is finally converted into boric acid The essential difference resides in the formation of Na O in the case of the use 85 of borax, which is generally favourable to the steel bath except perhaps in the case of steels produced with a high sulphur

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content, since Na O has a known desulphurising action in a bath of ferrous metals 90 Borax and boric acid have moreover the property of converting oxides into the corresponding borates; on the other hand, boric acid acting in extrerzis through its water of constitution, whether starting with borax, boric acid or 95 both, dissolves metal oxides at a red heat The water of crystallization of borax can be used, however, to assist the desired effect or to produce the effect sooner over a wide range of temperatures 100 It will be understood that these properties moreover give the coating layer a kind of cleansing and fluidizing effect which experience has shown to be most favourable. The borax and boric acid are used in pow 105 dered form As for the carbonaceous materials, they can be used likewise in powdered form or in the liquid state, in order to give more body to the coating while preventing it from flowing at too low a temperature, more especially under 110 the action of radiations from the molten metal bath It is to be noted that the formation of CO or CO,, due to the presence of these carbonaceous materials, increases under given conditions the desired effects of peripheral tur 115 bulence, and the effect of CO or CO in conjunction with the effect of the liberation of steam or of its constituent gases can be used to advantage, whereas the turbulence produced by the CO and/or CO 2 alone would be quite 120 inadequate to obtain the desired action. It will be observed moreover that the product according to the invention has the advantage of not giving rise to the release of any toxic products, which is not the case with pro 125 ducts derived from tars and bitumens thinned with gas oils or with diluents from the distillation of coal or heavy petroleum oils. The carbonaceous substances entering into the composition of the product according to 130 -785,823 the invention and at the same time as the borax and/or boric acid, can be charcoal, peat, a mineral carbon, a natural or synthetic cellulosic substance, very fine sawdust or wood flour, a residue from sugar manufacture, molasses, vinasses and the like. When the carbonaceous material used does not contain exclusively carbon, which is the general case, it is generally advantageous to treat it with caustic soda, in order to convert the substances which are foreign to carbon into fusible alkaline salts which are entrained in the liquid part of the bath, at the same time as the residues from the borax and boric acid, after the dehydration and the reactions taking place on contact of the coating and the molten metal bath. The residue from the coating according to the invention and the impurities of the bath are 2 ( strictly localized in the central part of the bath surface, and finally are accommodated right at the top of

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the ingot, in the part which must necessarily be eliminated, which only constitutes a very small proportion of waste; on the other hand, ingots treated according to other processes continue to present surface flaws and inclusions in the heart of the ingot which hitherto it has been impossible to eliminate. It should be noted that the fact of producing the steam or the gases, hydrogen and oxygen, of which it is composed, on the internal wall of the ingot mould and contrary to the established theoretical assertions, cannot in any way cause any undesirable effects at the heart of the ingot, because the formation and liberation of the said steam and gases takes place under welldefined conditions of temperature, speed and orientation. Table I below gives some examples of compositions according to the invention which have given excellent results during practical tests, the compositions being given in powder form and for one metric ton of product. TABLE I. Example 1 Example 2 Example 3 Substance kg kg i kg. Very finely powdered charcoal Natural graphite 70 % C Caustic soda Molasses Borax and/or boric acid Water for dissolving the caustic soda 470 23 410 1000 280 485 1000 820 1000 It is to be noted that the composition of Example I contains a minimum of 9.7 X 43 7 -4.2 % of water of constitution, when the boric acid is used alone. The table above indicates the quantities of water provided for forming the solution of caustic soda which allows the products according to the invention to be in powdery form. Owing to the exotgermic reaction which takes place during the preparation, this water evaporates for the greater part, which explains why it has not been reckoned in the addition for 1000. The preparation of these three products which are of appreciably different composition is quite easy. EXAMPLE 1. The charcoal and soda lye are mixed and while the mixing is taking place the quantity of molasses is poured in gradually until the moving mass assumes a powdery appearance. At this point the very finely powdered borax and/or boric acid is or are added to the first mixture and mixing is continued until the product is quite homogeneous The product obtained according to the invention and for the motives indicated above is suitable for all ingots, but more particularly for top poured ingots of large cross section, such as forge ingots, or bottom poured ingots, especially in the case of high viscosity steel. EXAMPLE 2. The charcoal and graphite are mixed, then the caustic soda lye is

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added, and mixing is carried out for a slightly longer period than in the foregoing example in order to allow time for the constituents other than the carbon to be attacked The borax and/or baric acid is or are then added and mixing is continued for some time to obtain the necessary homogeneity. This product is likewise suitable for casting all ingots, but more especially for ingots of small cross section and for killed steels of low viscosity or for effervescent steels. EXAMPLE 3 90 Production is similar to that of Example 2, but the caustic soda lye must be left to attack the graphite for a longer time than in Example 2, before adding borax and/or boric acid The product obtained is also in the powdery state, 95 i. as in the two foregoing examples This product, applied on the ingot mould wall, gives a very hard film On this account, it is more particularly suitable for effervescent steels which are top-poured to avoid more especially bottom splashes. Although the products according to the invention can be diluted directly with water to the consistency desired for the intended uses, these products are preferably obtained in powdery condition for convenience in transport and storage. To obtain the coating in the desired consistency for use, it is only necessary to dilute the powder with water on the site at the time of use, until a degree of fluidity is obtained which will make it is possible to apply the desired covering by the means selected, such as spray gun, paint brush, or other kinds of 2 C brush, spatula, scraper, etc To give some idea, for applying the product by means of a spray gun, the powder can generally be diluted with an equal weight of water. The most suitable mould temperature for applying the coating is between 600 and 80 C., yet thie coating according to the invention can be applied without difficulty to cold moulds. It will be noted that the product according to the invention can be again diluted with water after it has dried without losing its efficacy, even after it has been left in a dry state for a long time in the coating tank, and this stability, on various occasions, due to the physio-chemical properties of the selected constituents, is noteworthy. Drying of the coating takes place very quickly before the casting operation; about ten minutes is sufficient at room temperatures. After all, if there were a small amount of diluting water still left, it would very quickly be eliminated at the beginning of casting under the action of the intense radiated heat of the stream of molten metal, so that in actual fact on contact with the molten metal there remain

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only the constituents giving off water of crystallization and/or water of constitution, and the mixing water does not take part in the desired effervescence which is due on one hand to the transformation into steam or hydrogen and oxygen of said water of crystallisation and/ or constitution and on the other, to the gases resulting from the combustion of the carbonaceous substance or substances. A second group of examples of products according to the invention is given in Table II below These products have a particularly advantageous use in the case of a high alloy steel containing for example 4 %O of Ci (chromium), this steel having been strongly " killed " with aluminium in the proportion of for example 10 kg per ton of steel, also in the case of a steel containing a high Si content, for example 2 %, etc Such steels are very difficult to pour, on account of their high viscosity. The coating provided for repelling the impurities of the bath to the central part of the bath surface should be such that its constituents are reliably eliminated. More particularly, the use of boric acid mixed with a mineral carbon or a purified graphite similar to that of electric furnace electrodes, or with charcoal which is as pure as possible, is quite suitable in this particularly difficult case. TABLE II. (COMPOSITION IN POWDERY OR SLIGHTLY PASTY FORM) Second group of examples range Substances of composition (kg) Graphite and/or carbon of any kind containing more than 90 % C, in powder form 500 to 900 Boric acid (powder) 500 to 100 1000 1000 It is to be noted that substances of Table II can contain a maximum of water of constitux 43 7 tion equal to -21 85 % i e about 22 %. Caustic soda can be added, either in the form of an aqueous solution, or as a powder, or in flake form, in a very easily determined proportion which allows the carbon impurities contained in the mineral or vegetable carbon to be converted into alkaline salts In practice, for treating carbon or graphite in this way, it is sufficient to add it to the above-mentioned mixtures from 3 to 5 of the quantity of carbon or graphite used. Molasses can be added to these compositions at the rate of 50-100 parts per thousand of the total weight of the composition, when the product obtained is not thick enough at the temperature of use, as may happen, depending on the quality of the carbon and the proportion of boric acid. This second group of examples behaves as expected on account of the fact that the boric acid is volatile in the presence of the steam which is given off under the action of the heat of the bath This giving off of steam, 785,923 785,823 even if it takes place in the

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atmosphere, cannot in any way hinder the personnel in charge of the casting; on the contrary, it has a benificial effect on the mucous membrane. The preparation of these products does not present any difficulty and is similar to that described in connection with the first three examples. During the casting and while the steel is rising, there is set up, due to the coating according to the invention, a peripheral turbulence of remarkable steadiness, having an amplitude of several centimetres directed obliquely from bottom to top, which has not hitherto been obtainable with any known coating Thisi turbulence is produced regularly up to the height of the ingot mould, which confirms that the characteristics of the product are not affected by the mixing water or by the heat radiated from the bath The residue of the product floats entirely on the surface as a small grey sheet which is more or less copious depending on the amount used for coating the walls. This sheet grows as the level of the bath rises because all the impurities introduced by the stream of metal are driven towards the centre and upwards, so much so that the grey sheet is located rigorously at the centre of the si rface of the bath, which is likewise essential for leading to the desired result, especially as regards the total removal of non-metallic inclusions; this proves moreover that the constituents of the product are likewise driven towards the centre of the bath surface, this being due to the presence of borax or boric acid at the time of their melting. All the tests carried out by the applicant have shown that ingots cast in ingot moulds coated according to the invention have neither non-metallic inclusions, nor blow holes, either in the case of bottom pouring or in the case of top pouring. On the other hand, in the course of one of these tests, part of the wall of an ingot mould was intentionally left uncoated to see what would happen It is noteworthy that a clearly apparent surface flaw was produced, localised exactly at the part which had not been covered with a coating according to the invention, while the rest of the ingot was perfect, without the slightest flaw and had a perfect sutrface without any blow holes or under-thesurface inclusions. It is to be noted that the direction in which gases are given off varies slightly depending on whether bottom pouring or top pouring is used, on whether the ingot mould has vertical walls, or oblique walls, whether it widens out towards the top or the bottom, which naturally follows moreover in consequence of the component of the stream of metal and the component of the reaction of the wall, which both come into consideration. Obviously the invention is not in any way limited to the numerical

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examples given.

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