| 摘要 |
PURPOSE:To degrease and was an uncoated molded PP resin part with a specific aq. alkaline soln. to improve the washability and safety thereof. CONSTITUTION:5-50g/l CaCO3 and 1-10g/l polyoxyethylene polynuclear phenol of 8 to 12 in HLB and, if necessary, 0-5g/l alkali metal salt of a polycarboxylic acid having a mol.wt. of 50,000 to 100,000 are dissolved in water to obtain an aq. alkaline soln. The aq. alkaline soln. is heated at 50 to 70 deg.C, and sprayed on an uncoated molded PP resin part at a pressure of 1 to 5kg/cm<2> for 30 to 90sec to degrease and wash the latter with the former, followed by washing with water. Subsequently, an aq. soln. contg. 0.1-5g/l polyoxyethylene higher alcohol of 12 to 16 in HLB and heated at 5 to 50 deg.C is sprayed on the molded part at a pressure of 0.3 to 0.8kg/cm<2> for 10 to 30sec, followed by blowing thereagainst hot air of 70 to 80 deg.C for 5 to 10min for drying thereof. |
