RHOPLEX CL-106 Acrylic Emulsion For Factory-Applied Clear Topcoats on Wood With Excellent Hardness, Mar Resistance, and Clarity

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1 RHOPLEX CL-106 Acrylic For Factory-Applied Clear Topcoats on Wood With Excellent Hardness, Mar Resistance, and Clarity Description RHOPLEX CL-106 acrylic emulsion has been designed for use in factory-applied clear topcoats for wood requiring the highest levels of appearance and surface hardness characteristics. Lacquers based on RHOPLEX CL-106 acrylic emulsion are translucent in the can and upon application turn clear very rapidly while drying. RHOPLEX CL-106 acrylic emulsion was developed for use in topcoat finishes and as such does not provide optimum appearance qualities if used as a sealer. In multi-coat systems, the finest overall appearance is obtained when RHOPLEX CL-106 acrylic emulsion is used over specialized sealer formulations. It is recommended that RHOPLEX CL-106 acrylic emulsion be used over sealers formulated from RHOPLEX CL-105 emulsion. In this manner, RHOPLEX CL-105 emulsion contributes excellent wood fiber wetting, appearance characteristics, and early sandability to the system while RHOPLEX CL-106 emulsion provides a topcoat with hardness, mar resistance, and clarity. The volatile organic content (VOC) of typically formulated clear topcoat lacquers is less than 2.3 lb/gal and hazardous air pollutants (HAPs) are 0.3 lb HAPs/lb solids. Typical Properties These properties are typical but do not constitute specifications. Appearance Weight solids, % 42.0 Volume solids, % 39.8 ph 8.4 Viscosity, cp 300 Density, lb/us gal Wet Dry Bulking value, US gal/lb Wet Dry White, translucent liquid Minimum Film Formation Temperature, C 70 VOC, as supplied, g/l max. 3.0 Freeze/thaw stability Protect from freezing Mechanical stability, Passes 5 min. Waring Blender Heat stability (10 days/140 F) Passes Performance Advantages Topcoats formulated from RHOPLEX CL-106 emulsion offer the following features: Water-white Resistant to yellowing Hard, mar resistant film Broad stain resistance

2 Recommended Uses Wood topcoat formulations based on RHOPLEX CL-106 acrylic emulsion are recommended for spray application over aqueous or solvent-based sealers. Optimum use conditions for spray application are in moderate relative humidity followed by a "flash-off" period of 10 to 15 minutes. Low air flow rates in the flash-off area are recommended to assist film drying and microfoam release. Force drying for 10 to 15 minutes at 120 to 130 F with moderate air flow provides films which are dry and ready for handling. Typical Performance The following characteristics of lacquers based on RHOPLEX CL-106 acrylic emulsion were determined in our laboratory using the recommended starting-point formulations. Appearance Properly formulated lacquers based on RHOPLEX CL-106 emulsion possess excellent clarity. These lacquers provide films with overall hardness and mar resistance. Hardness and Mar Resistance Because films formulated from RHOPLEX CL-106 emulsion are hard, their mar resistance relative to other thermoplastic lacquers is excellent. Fingernail mar resistance of lacquers formulated from RHOPLEX CL-106 emulsion is superior to that provided by other thermoplastic emulsions. Table 1 compares the hardness of films made from various emulsions using recommended formulation procedures. Film Color and Resistance to Yellowing The all acrylic composition of RHOPLEX CL-106 emulsion yields films which are resistant to yellowing. The yellowing characteristics of lacquers based on RHOPLEX CL-106 emulsion are described in Table 2. Table 1 Sward Rocker Film Hardness From Aqueous Lacquers Using Selected Thermoplastic s Sward Hardness RHOPLEX CL RHOPLEX CL RHOPLEX CL RHOPLEX WL Nitrocellulose 30 Note: All aqueous lacquers used their recommended fast-dry coalescent packages. Coatings were applied on wood, with 1 coat sealer and 2 topcoats and allowed to air dry six weeks before Sward test.

3 Table 2 Yellowing Characteristics of Selected Aqueous s Colorimeter Film Measurements QUV Exposure (Accelerated Weathering) RHOPLEX CL-106 Competitive Hard Thermoplastic Unexposed Hour Exposure Note: Colorimeter yellow reflectance measurements (b*) were measured on films drawn down on white aluminum panels at 2 mils dry. A difference of 0.5 can be visually observed. The higher the value, the more yellow the film. Stain Resistance The stain resistance of RHOPLEX CL-106 based coatings to moisture, alcohols, and common kitchen staining agents compares favorably to solventborne nitrocellulose lacquers. The stain resistance of aqueous lacquers formulated with RHOPLEX CL-106 emulsion is summarized in Table 3. Table 3 Water, Alcohol, Stain, and Cleanser Resistance of Lacquers Using Formulation CL Reagent RHOPLEX CL-106 RHOPLEX CL-104 Nitrocellulose Water % Ethanol Formula % Dreft Mustard Vinegar The films were spray applied to solid maple in three coats at a total film thickness of 2½ dry mils and allowed to air dry for two weeks. These staining agents were applied to the film, covered by a watch glass, and allowed to set for 16 hours. They were then wiped off and the film was evaluated for extent of damage and recovery. Ratings are on a 1 to 10 scale with 10 indicating no effect. Cold Check Resistance Formulation CL passed cold check testing through 20 cycles matching the performance of a nitrocellulose topcoat. A cycle consists of 120 F/5 F/ambient with one hour at each condition. Finishes were examined microscopically for any cracking perpendicular to the grain after each cycle. Tests were conducted on maple on which one aqueous sealer was applied followed by two aqueous topcoats. Coatings were air dried 30 minutes between applications. The finished systems were air dried for two weeks prior to cold check cycle testing. Coatings were applied with conventional air spray equipment. Formulating Guidelines Specific comments on coalescents and other components are provided to facilitate your evaluation of formulations with RHOPLEX CL-106. Defoamers Tego Foamex 805 is a recommended defoamer which can be used at levels of 1 to 2% on polymer solids. Coalescents Formulations based on RHOPLEX CL-106 emulsion require the use of coalescing solvents for good film formation. Formulations should be allowed to equilibrate for at least 16 hours after coalescent addition to obtain representative test results. The coalescent blend recommendations used in the starting point formulations in these notes provide excellent film formation over a broad range of application conditions. They should be followed at least for initial evaluations. Reducing the level of coalescents will allow the coating to dry more rapidly and be

4 handled more quickly; however, excessive reduction will lead to property loss in cold check, appearance, and staining characteristics. Coalescents and plasticizer should be premixed and then added to water. This premix must be added slowly to the vortex of the kettle or in some manner where uniformity and dispersion is assured. Selection of the optimum coalescent system depends on drying speed requirements, ambient temperature and relative humidity, and the availability of ovens for drying. Coalescent selection is discussed at length in the Rohm and Haas publication, Wood Street Flyer (# 001) Replacing Ethylene Glycol-Based Coalescents. Plasticizers Due to the hardness of RHOPLEX CL-106, the use of a plasticizer is required to assure proper film formation characteristics. Plasticizer is recommended in all formulations, even blends, at a level of 5% on RHOPLEX CL-106 solids. The plasticizer must be pre-mixed with the cosolvent before the addition to the emulsion. Plasticizers such as PARAPLEX WP-1 are recommended. Control of Microfoam Microfoam can become entrapped in a film when the time for film setting is less than the time for foam dissipation. Spray application in relative humidity conditions of 35% or lower, and/or in high temperatures, will increase the tendency for microfoam entrapment. Microfoam entrapment in the drying film typically occurs in the first 2-4 minutes after spraying. Four variables which can be adjusted to reduce microfoam entrapment are: Coalescent Selection Increase the level of low volatility coalescents, such as Dowanol DP and DPM, to keep the film open during drying. Optimizing spray gun setting Solids/Viscosity Level Reducing the solids level to 25-28% in the formulation will also increase film open time by leaving more water in the film after spraying. Formulation viscosity can be maintained by using ACRYSOL RM-825 rheology modifier. Lowering the viscosity, while maintaining vertical sag resistance, will aid in controlling microfoam. Flash Conditions Reducing the air flow rate across coated parts during the flash period will slow drying and increase the time for film setting. Mar Aids Tego Glide 410 is a recommended mar aid which offers excellent slip and surface feel. Mar resistance is also improved by the use of Michem Waxes should be carefully evaluated to avoid formulation difficulties and should not be premixed with coalescents, as this can lead to seeding and hazy films. Waxes should be added to the formulation just prior to any water used for solids or viscosity adjustment. Flatting Aids To lower the gloss of topcoat formulations based on RHOPLEX CL-106 emulsion, flatting aids such as Syloid 169 can be used. Wetting Agents "Picture framing" may result from poor wetting particularly on non-porous, sealed substrates. With other wood coating emulsions, our experience indicates that the use of surfactant at 1% on solids in the formulation can prevent this effect. Surfynol 104DPM at 1% to 3% on formulation solids is recommended for this purpose. Formulations The recommended sealers for use under RHOPLEX CL-106 emulsion are ones based on RHOPLEX CL-105 emulsion. See Formulation CL in the literature for RHOPLEX CL-105 emulsion. Formulation CL is a recommended starting point for evaluating RHOPLEX CL-106 emulsion as a topcoat.

5 Formulation CL Waterborne Lacquer Clear, Gloss Topcoat Based on RHOPLEX CL-106 Ingredients Pounds Gallons Weight Percent RHOPLEX CL Premix the following*: Ethylene glycol monobutyl ether (EB) Diethylene glycol monobutyl ether (DB) Dipropylene glycol monomethyl ether (DPM) PARAPLEX WP Water While mixing, slowly add the premix to the RHOPLEX CL-106 emulsion. Surfynol 104DPM ACRYSOL RM-825 Rheology Modifier Tego Glide 410 (50% in DPM) Tego Foamex Michemlube Water Total Formulation Constants Weight Solids, % Volume Solids, % Weight/Gallon, lbs 8.46 ph 8.0 to 8.5 Viscosity, #2 Zahn cup, seconds 25 to 30 VOC, g/l VOC, lb/gal 2.3 HAPS, lb/lb, solids 0.3 *Mix EB, DPM, DB, and PARAPLEX WP-1 together first, then add water before adding to RHOPLEX CL-106 emulsion.

6 Suppliers of Suggested Raw Materials Product Type Supplier ACRYSOL RM-825 Thickener Rohm and Haas Company Diethylene Glycol Monobutyl Ether (DB) Coalescent Dow Chemical Union Carbide Dipropylene Glycol Monomethyl Ether (DPM) Coalescent Dow Chemical Union Carbide Ethylene Glycol Monobutyl Ether (EB) Coalescent Dow Chemical Union Carbide Michem Wax Michelman Chemical PARAPLEX WP-1 Plasticizer Rohm and Haas Company RHOPLEX CL-106 Rohm and Haas Company Surfynol 104DPM Wetting Agent Air Products Syloid 169 Flatting Agent W.R. Grace & Co. Tego Foamex 805 Defoamer Goldschmidt Chemical Corp. Tego Glide 410 Mar Aid Goldschmidt Chemical Corp. Safe Handling Information Based on its composition, RHOPLEX CL-106 is not expected to be toxic via single oral, dermal or inhalation exposure. It may be a mild skin, eye or respiratory irritant. Material Safety Data Sheets Rohm and Haas Material Safety Data Sheets (MSDS) contain pertinent information that you may need to protect your employees and customers against any known health or safety hazards associated with our products. Under the OSHA Hazard Communication Standard, workers must have access to and understand MSDS on all hazardous substances to which they are exposed. Thus, it is important that you provide appropriate training and information to your employees and make sure they have available to them MSDS on any hazardous products in their workplace. Rohm and Haas Company sends MSDS for all its products, whether or not they are considered OSHA-hazardous, to both the "bill to" and/or "ship to" locations of all its customers upon initial shipment, including samples. If you do not have access to one of these MSDS, please contact your local Rohm and Haas representative for an additional copy. Updated MSDS are sent upon revision to all customers of record. In addition, MSDS are sent annually to all customers receiving products deemed hazardous under the Superfund Amendments and Reauthorization Act. MSDS should be obtained from your suppliers of other materials recommended in this bulletin. Rohm and Haas Company is a member of the American Chemistry Council (ACC) and is committed to ACC s Responsible Care Program.

7 ACRYSOL, PARAPLEX, and RHOPLEX are trademarks of Rohm and Haas Company or of its subsidiaries or affiliates and are intended to designate goods marketed in North America; the same goods may be marketed in other countries, generally under other Company trademark designations. These suggestions and data are based on information we believe to be reliable. They are offered in good faith, but without guarantee, as conditions and methods of use of our products are beyond our control. We recommend that the prospective user determine the suitability of our materials and suggestions before adopting them on a commercial scale. Suggestions for uses of our products or the inclusion of descriptive material from patents and the citation of specific patents in this publication should not be understood as recommending the use of our products in violation of any patent or as permission or license to use any patents of the Rohm and Haas Company. Rohm and Haas, 2009 All rights reserved. September W6