1B31 Acrylic Coating System Description A fast air drying, single component, acrylic coating that provides excellent moisture and environmental protection for printed circuit assemblies. The final film demonstrates excellent flexibility and is easily repairable. This coating is MILI-46058C and IPC-CC-830 qualified. Fluoresces under UV light for ease of inspection. Properties of Liquid HumiSeal Specific weight, (lb. per gal.) per ASTM, Meth. D1475 Solids Content, % by weight per Fed-Std-141, Meth.4044 Viscosity, centipoise per Fed-Std--141, Meth. 4287 Flashpoint, 0C (0F) per ASTM, Meth. D56 VOC (grams / liter) Drying Time to Handle per Fed-Std-141, Meth.4061 Recommended Coating Thickness Recommended Curing Conditions Time Required to Reach Optimum Properties Thinner, if needed (dipping & brushing) (spraying) Recommended Stripper Pot Life at Room Temperature Shelf Life at Room Temperature 7.6 ± .2 35 ± 3 197 ± 15 -1 (30) 592 10 minutes 1 - 3 mils 24 hrs @ rm. temp or 30 min.@ 1700F 7 days Thinner 503 Thinner 521 Stripper 1080 12 months 12 months Properties of Cured HumiSeal Thermal Properties Continuous Use Operating Range 0C(0F) Thermal Shock, per MIL-I-46058C Solderability Coefficient of Thermal Expansion - DMA Glass Transition Temperature - TMA Young’s Modulus - DMA Physical Properties Clarity Build per Dip, mils, per ASTM, Meth.D823 Flexibility, per MIL-I-46058C Adhesion, per ASTM, Meth. D2197 Flammability, per ASTM, Meth. D635 Weather Resistance Electrical Properties Dielectric Withstand Voltage, volts per MIL-I-46058C Dielectric Breakdown Voltage, volts, per ASTM, Meth. D149 Dielectric Constant, at 1MHz and 250C, per ASTM-D150-65T Dissipation Factor, at 1MHz and 250C, per ASTM-D150-65T Insulation Resistance, ohms, per MIL-I-46058C Moisture Resistance, ohms, per MIL-I-46058C Chemical Properties Main Constituent Fungus Resistance, per ASTM-G21 Resistance to Chemicals -650C (-850F) to +1250C (2570F) Passes Excellent 55ppm / 0C 140C 1000 psi Transparent 2 Excellent Excellent Self-Extinguishing Very Good >1,500 7500 2.5 0.01 800 x 1012 (800T) 60 x 109 (60G) Acrylic Passes Fair Values are not intended for use in preparation of specifications. Revised 06-18-04 Page 1 of 2 1B31 Acrylic Coating APPLICATION Cleanliness of the substrate is of extreme importance for the successful application of a conformal coating. Surfaces must be free of moisture, dirt, wax, grease and all other contaminants. Contamination under the coating will cause problems that may lead to assembly failures. HumiSeal coatings may be applied by brush, dip or spray. Dipping Depending on the complexity, density and configuration of components on the assembly, it may be necessary to reduce the viscosity of HumiSeal 1B31™ with HumiSeal Thinner 503 in order to obtain a uniform film. Once optimum viscosity is determined, a controlled rate of immersion and withdrawal (2 to 6" per minute) will further insure even deposition of the coating and ultimately a uniform film. During the application, evaporation of solvent causes an increase in viscosity that should be adjusted by adding small amounts of Thinner 503. Viscosity in the dip tank should be regularly checked by the use of a simple measuring device such as a Zahn or Ford viscosity cup. Spraying HumiSeal 1B31™ can be sprayed using conventional spraying equipment. As a rule, the addition of Thinner 521 is necessary to assure a uniform spray pattern resulting in pinhole free film. The amount of thinner and spray pressure will depend on the specific type of spray equipment used. The spraying should be done under an exhaust hood so that the vapor and mist are carried away from the operator. The recommended ratio of HumiSeal 1B31™ to HumiSeal Thinner 521 is 1 to 1 by volume, as a starting point. The quantities may be adjusted to obtain a uniform coating. Brushing HumiSeal 1B31™ may be brushed with a small addition of HumiSeal Thinner 503. Uniformity of the film depends on component density and operator's technique. Storage HumiSeal 1B31™ should be stored at room temperature, away from excessive heat, in tightly closed containers. HumiSeal products may be stored at temperatures of 0-100°F. Avoid direct sunlight. Prior to use, allow the product to equilibrate for 24 hours at 65-90°F. Caution The solvents in HumiSeal 1B31™ are flammable. Do not use in presence of open flame or sparks. Avoid inhalation of vapors or spray. Use only in well-ventilated areas. Avoid contact with skin and eyes. If contact occurs, wash with soap and water. If swallowed, call physician immediately. Refer to MSDS before use. All technical data in this bulletin is based on test results and is believed to be correct. However, since the end use of HumiSeal materials (and the manner of storing and handling them) is beyond our control, we make no warranty-expressed or implied as to the fitness of use, results to be obtained from or effects of use with respect to these materials. Their use shall be solely by the judgment of and at the risk of the user notwithstanding any statement in this bulletin. © Copyright 1992 CHASE CORPORATION. HumiSeal and 1B31™ are trademarks of Chase Corporation. HumiSeal Division Chase Corporation Woodside, NY 11377-0445/Tel: (718) 932-0800/Fax: (718) 932-4345 [email protected] Revised 06-18-04 Page 2 of 2