1、 ENGINEERING MATERIAL SPECIFICATION Material Name Specification Number Date Release No. Release/Revision 2011 06 17 N Status No Future Use J. Crist, NA 1985 05 09 CAP1-RD531694 Released WP 3948-a Page 1 of 2 SURFACE TREATMENT FOR THERMOPLASTIC POLYOLEFIN ESB-M98P1-A ELASTOMERS (TPO) NOT TO BE USED F
2、OR NEW DESIGN 1. SCOPE This specification defines the performance requirements for the paint pretreatment system for thermoplastic polyolefin (TPO) parts which are subsequently primed and color coated. 2. APPLICATION This specification was released originally for TPO parts where maximum paint adhesi
3、on is required. The specified treatment, produces a clean, conditioned surface suitable for painting. 3. REQUIREMENTS 3.1 SUBSTRATE The TPO molded part must be fully cured and free from pits, blow holes and/or white powdery bloom. 3.2 SURFACE TREATMENT 3.2.1 Thoroughly clean the part with the approp
4、riate cleaning solution and power wash equipment to remove all soil and contaminates. A 60 s wash maintained at 71 - 82C at 90 kPa minimum spray pressure is required. 3.2.2 Rinse with 3 (15 s minimum) spray rinses. The final rinse must be deionized water with a maximum conductivity of 20 microsiemen
5、s/cm. 3.2.3 Drain and dry with hot air. 3.2.4 Within 30 min after completion of 3.2.3, spray parts with a dilute solution (5-10%) of benzophenone in a solvent that thoroughly wets the part, without runs and drips, and that has a sufficiently rapid rate of evaporation for the part to appear dry withi
6、n 1 min after spraying. The dry benzophenone coating weight must be within 0.03 - 0.31 mg/cm2. ENGINEERING MATERIAL SPECIFICATION ESB-M98P1-A WP 3948-b Page 2 of 2 3.2.5 Within 30 min after completion of 3.2.4, expose the entire part surface to be painted to radiation from a quartz jacketed mercury
7、vapor arc. The radiation that falls on the surface must contain 0.05 to 0.4 J/cm2 in the energy wave length band 365 +/- 5 nm (nanometers). The part surface temperature must not exceed 149C during radiation exposure. 3.3 PAINTING Primer-surfacer must be applied within 30 min after performing step 3.
8、2.5 followed by enamel color coat. Primer-surfacer and enamel must be applied at film thicknesses specified in Performance Specification ESB-M2P105. Only approved materials shall be used. 4. GENERAL INFORMATION This information is for direction of the user and is not a requirement for the supplier. 4.1 MATERIALS Elastomer, Thermoplastic Polyolefin ESB-M2D246 Primer-Surfacer ESB-M6J128 Conventional Enamel ESB-M2J121 Basecoat/Clearcoat Enamel ESB-M2J218-A1/A2 4.2 PATENT APPLICATION Some or all of the processing steps prior to paint application may be covered by patent.
