New Architectural Coatings Technology Targeted At Stricter Hospital Infection Protocols

Steven Reinstadtler, Industrial Marketing Manager - Coatings

Kathy Allen, Technology Manager - 2K WB Coatings

Abstract: For the hospital administrator who is concerned with meeting the newer Center for Disease Control (CDC) and The Joint Commission (formerly the Joint Commission on Accreditation of Healthcare Organizations (JCAHO)) protocols without sacrificing aesthetics and durability, there are new developments in architectural coating technologies for targeted hospital environments that require a higher frequency of cleaning with harsher disinfectants. These novel coatings technologies offer improved durability and resistance to harsh cleaners and disinfectants without sacrificing appearance. The discussion will cover some of the requirements, chemicals involved, testing and case history related to this topic. Introduction

Hospital Acquired Infection (HAI) has become a major threat to human life over the past several decades with an increased volume of patients requiring medical attention and the ongoing resistance of certain microbes to traditional antibiotics. Hospital administrators have come under increasing pressure from health organizations such as the CDC and The Joint Commission to change or update standard facility protocols. With more stringent disinfecting requirements, some areas of higher contamination risk are being cleaned more often and with harsher cleaners. This poses a challenge for traditional architectural wall paints. New developments in waterborne polyurethane based coatings technology address these tougher requirements without sacrificing other desirable aesthetic qualities such as color stability and low gloss options. Background

In 2008, the CDC revised the protocols for the safe operation of a healthcare facility. These protocols are referred to as the Guideline for Disinfection and Sterilization in Healthcare Facilities. Some of the changes affected the way critical areas such as emergency, operating and procedure rooms are disinfected between each use as well as during terminal cleaning [1]. By requiring horizontal and vertical surfaces to be cleaned more often, the existing wall paint is subjected to increased abrasion which it may not have been exposed to in the past. Additionally, new regulations on the types of disinfecting cleaners and their strength have challenged the chemical resistance inherent in these types

of architectural coatings. In order to compensate, hospital facility managers and the architects who specify these paints have been forced to limit their design palette of acrylic latex paints to only gloss or semi-gloss finishes. Other more durable coating options such as epoxy have had limited success due to the unacceptable odor during application. In many discussions with architects, consultants, and hospital facility owners, three main attributes for a hospital wall coating were shared - low odor, durability, and price [2]. The weighted attributes considered during these discussions are depicted below in Chart 1.

Chart 1: Weighted Attributes from Hospital Facility Owners and Architects

Based on these desired attributes a study was initiated to determine a baseline of performance for the common hospital architectural paints and alternative coatings. Then a waterborne polyurethane option was developed and compared to the baseline data to note any improvements in key desirable traits. A waterborne polyurethane coating was selected due to the low odor, durability, and the ability to adjust gloss demonstrated in other adjacent market area [3].

Experimental Based on the discussions with hospital facility managers and recommendations from their paint manufacturers in these targeted environments, several architectural waterborne acrylic latex wall paints were purchased and applied to wallboard samples following the manufacturer’s directions. Additionally, four waterborne epoxy coatings were included in the testing based on an internet search for higher performance wall coatings and the subsequent recommendation on two coating supplier web pages on this topic.

Price

25%

Labor Cost

4%

VOC

4%

Room

Availabil ity

4%

Durability

30%

Odor

33%

Several two component (2K) waterborne polyurethane coating technologies available from Bayer MaterialScience were also considered for use in this environment due to their desirable physical traits. These traits include:

- Near zero VOC formulas with excellent abrasion and chemical resistance - Minimal odor when applied in a hospital environment - Adjustable gloss levels including gloss, semi-gloss, eggshell, and matte

This 2K waterborne polyurethane technology will be referred to going forward as Bayer’s HD Wall Coating Technology. Guide formulas were prepared using Bayer MaterialScience waterborne resins along with the necessary additives. Two gloss levels were chosen based on 1) the current commonly used paints and 2) the aesthetics desired by hospital administrators. These targeted gloss levels were achieved not by incorporating significant quantities of matting aids (i.e. silica flattening agents) but by the resins employed in the formula. A hydrophilic HDI trimer, was used as the hardener with a NCO:OH ratio of 3:1. The guide formula coatings were applied at approximately 4-6 wet mils with a dry mil thickness of approximately 2-3 mils per coat. Dry times for the coatings ranged from 2.5 hour for the matte formulas to approximately 4 hours for the gloss formula. The trend was noted that as the formulas were made to be less glossy, the dry time was reduced. For the purpose of the following testing, the Bayer HD Wall Coating Technology with the low gloss was used since it represented the aesthetic desires of the architect as well as the worst case scenario in regards to durability for the facility owner. Testing Wallboard panels were primed with a standard wall primer, coated with the test paints and coatings, and allowed to age for 7 days to eliminate the effects of cure time. Then several tests were performed to determine the durability of the finishes. These results are summarized in Table 1. Pictures of two of the tested samples for comparison are included in Picture 1 and 2.

Table 1. Durability Testing Comparison of Paints and Coatings* Paint or Coating *values are typical VOC*

(g/L) Gloss (60º)

Clorox Cleanup Double Rub (after 7day cure)

Ecolab Disinfectant Cleaner® Double Rub (after 7 day cure)

Betadine® ** (1 hr spot test)

1K Waterborne Acrylic 1 44 2 54 104 3 1K Waterborne Acrylic 2 40 5 62 380 2 1K Waterborne Acrylic 3 0 7 250 400+ 2 1K Waterborne Epoxy A 155 11 280 400+ 2 1K Waterborne Epoxy B 96 28 320 400+ 2 1K Waterborne Epoxy C 96 12 275 400+ 2 2K Waterborne Epoxy 169 12 205 400+ 2 Bayer’s HD Wall Coating

2 6 400+ 400+ 1

*from published literature **0= no stain 1= faint stain 2= yellow stain 3= brown stain

Picture 1: Typical Waterborne Acrylic Picture 2: Bayer’s HD Wall Coating Technology Low Gloss Low Gloss

Since odor was a point of major concern for hospitals, a subjective double blind odor test was devised since one did not exist that quantifies the odor for this type of application. Dubbed “The Sniff Test”, a panel of volunteers with technical and commercial backgrounds were asked to rate the paints and coatings on a scale of 1-5. These results are reported in Table 2.

Table 2. Odor Test* Paint or Coating Odor Value (1= low, 5= high) 1K Waterborne Acrylic 1 1 1K Waterborne Acrylic 2 1 1K Waterborne Acrylic 3 2 1K Waterborne Epoxy A 4 1K Waterborne Epoxy B 4 1K Waterborne Epoxy C 4 2K Waterborne Epoxy 5 Bayer’s HD Wall Coating Technology 1 *values are typical

Discussion In the testing protocol shown in Table 1, the double rubs represent the durability and cleanability of the coatings. The HD Wall Coating Technology outperforms the 1K waterborne acrylic, the 1K epoxies,

and the 2K epoxies for durability against cleaning with Clorox. The durability against the Ecolab Disinfectant Cleaner® of Acrylic 3, Epoxy A, Epoxy B, Epoxy C, 2K Epoxy, and the HD Wall Coating Technology is equal but better than Acrylic 1 and Acrylic 2. The HD Wall Coating Technology also has better resistance to staining from Betadine® than both the acrylics and the epoxies. The odor test in Table 2 shows that the odor of Acrylic 1, 2, and the HD Wall Coating Technology as the lowest. With odor, durability and cleanability of the coating being major points of concern for the hospital administrators, the results show that the HD Wall Coating Technology would provide the best overall properties to meet these requirements. However, there were other desired attributes that were discussed with the owners and designers of hospital facilities. One of these attributes was the ability to use lower gloss coatings to impart a desired aesthetic quality to the room. Architects and interior designers indicated that they prefer an eggshell or matte finish to give the room a softer, more welcoming look. This could be done with traditional paints but the additives that are used to lower the gloss reduce the abrasion resistance and increase the dirt pick up of the wall surface. Therefore, facility owners have had a preference for gloss or semigloss finishes primarily for durability reasons. As previously detailed, resins that are used in the HD Wall Coating Technology inherently interacts with light in the final coating to cause a lower gloss without the need for copious amounts of property-reducing additives. Another factor affecting the choice of paint or coating is the total cost of maintenance. The total cost is a sum of labor and paint costs over a prescribed period of time. In the example summarized in Chart 2, a highly utilized operating room was being painted four times a year due to repeated cleaning with harsh disinfecting cleaners. In this economic waterfall example, a typical applied cost was used for a waterborne acrylic paint. Then subsequent costs were listed as the comparison was made to switching the one operating room over to the HD Wall Coating Technology for one year. The additional cost in red was related to the fact that a two component system cannot be mixed to the exact amount needed for one room. Therefore there is a small amount of reacted unused coating that is accounted for. This quantity of waste is dwarfed by the threefold reduction in the amount of paint used based on the higher durability allowing for four times the longevity. While the cost of the HD Wall Coating Technology is higher per gallon than a typical waterborne acrylic, the net paint cost is reduced as depicted in the third column. The largest savings that was realized was based on the major reduction in labor costs as recorded in the fourth column. This reduction in labor and the resultant costs also support the facility owner’s desire to use the hospital’s own staff painters more. Finally, the hospital staff that was interviewed indicated a slight reduction in expected cleaning time due to the smooth surface of the HD Wall Coating as compared to other paints. This translates into the cost listed in the fifth column.

Chart 2: Economic Waterfall Comparison Typical Waterborne Acrylic vs. HD Wall Coating Technology*

*values are typical Conclusion

A new waterborne polyurethane architectural wall coating technology has been developed that combines several sought after performance properties. Namely, this technology combines a very low VOC and odor level with an extremely high durability as measured by chemical and abrasion resistance. This unique combination of properties is very well suited for healthcare environments where low odor and high performance are both sought after properties. The use of this new waterborne polyurethane technology offers the hospital administrator the opportunity to significantly reduce the amount of repeat painting cycles due to the coatings’ inherent higher performance level. Additionally, the architect, designer, or facility manager can now specify or use low gloss or matte coatings for the desired aesthetic effects without sacrificing durability or increasing dirt pick up. For more information on Bayer’s HD Wall Coating Technology, please contact Bayer MaterialScience at 412.777.3983 or naftainfo@bayerbms.com

References:

1. Centers for Disease Control and Prevention, “Guideline for Disinfection and Sterilization in Healthcare Facilities”, Atlanta, GA. Centers for Disease Control and Prevention, 2008

2. Interviews with multiple architects, facility managers, and consultants in the U.S., 2010-2011 3. Reinstadtler, Steven R, “Environmentally Friendly Graffiti Resistant Coatings”, SSPC

Conference, February 2010

Biography

Steven Reinstadtler is the Industrial Marketing Manager for Coatings used in construction at Bayer MaterialScience’s Coatings, Adhesives, and Specialties Division in Pittsburgh, PA. He received a BS in Chemistry with a Polymer Science option from University of Pittsburgh. Steven joined Bayer MaterialScience in 1987 as a chemist working on formulating cast urethanes and high performance coatings. He transitioned into the Coatings area in 2006, where he was responsible for the R&D activities of the Construction Coatings group as well as forward marketing activities. Steven is currently the Industrial Marketing Manager responsible for identifying new polyurethane coatings markets and helping architects, engineers, consultants, and coatings professionals to build infrastructure with durability and sustainability in mind. Kathy Allen is the Technology Manager in the Coatings group at Bayer MaterialScience LLC in Pittsburgh, PA. She holds two degrees—a Bachelor of Science degree in Chemistry from Thiel College and an MBA from the University of Pittsburgh. Prior to working at Bayer, Kathy worked for an automotive paint supplier as an R&D chemist developing OEM automotive primers. Kathy started her career at Bayer in the Spray Technology Group, moved into the Construction Coatings Group and is now the Technology Manager for the 2K WB Coatings Group. She is currently responsible for the technical development supporting Bayer’s efforts to provide 2K WB protective coatings for various applications. These applications include automotive interior coatings, industrial and residential floor coatings, and graffiti resistant coatings.

Lit. # 20939