How to make the surface of the plastic plate products before

How to sign plastic products surface pretreatment of plastic signs, 塑料的迹象) Surface treatment products mainly include coating coating process and coating process of coating. In general, the crystallinity of plastic is bigger, smaller polarity or nonpolar, low surface energy, it will affect the coating and coating adhesion. Due to plastic products is a kind of non-conductive insulator, therefore cannot be directly by a plating process standard plating coating surface of the plastic tag, so before the surface treatment, should undertake the necessary pre-treatment, to improve the adhesion strength of the coating and coating for plating coating with good adhesion of the conductive layer. 1 coating coating pretreatment before treatment including plastic plate surface oil removal, cleaning the surface of the oil and release agent, as well as the activation treatment on the surface of the plastic panels, the purpose is to improve the coating adhesion of coating. ( 1) Plastic signs of oil removal. Like metal products surface oil removal, plastic signs except oil can use organic solvent cleaning or in alkaline aqueous solution containing surfactant oil removal. Organic solvent oil is suitable for the plastic surface cleaning of paraffin, beeswax, fat and other organic dirt, the insoluble organic solvents to plastic, swelling, cracking, its low boiling point, volatile, non-toxic and non-combustible. Alkaline aqueous solution is suitable for the alkali resistance plastic oil removal. Caustic soda, alkaline salt contained in the solution and all kinds of surface active substance. The most commonly used surface active substance for the OP series, alkyl phenol polyoxyethylene ether, it won't bubble formation, is no residue on the plastic surface. ( 2) Activation on the surface of the plastic panels. The activation is in order to improve the surface of the plastic signs, namely on the surface of plastic panels generate some polarity base or coarsening, in order to make is more likely to be adsorbed on the surface wetting and coating. Surface activation treatment method are many, such as chemical oxidation, flame oxidation, solvent vapor etching method and corona discharge oxidation method, etc. One of the most widely used is crystal chemical oxidation treatment method, this method is commonly used chromate treatment fluid, the typical formula is heavy chromium acid potassium 4. Water 5%, 8. 0%, concentrated sulfuric acid ( More than 96%) 87. 5%. Some plastic signs, such as polystyrene and ABS plastic, also may carry on the coating and coating directly. In order to obtain high quality coating coating, also useful chemical oxidation treatment, such as ABS plastic after degreasing, can use a thin chromic acid etching processing fluid, its typical processing formula for chromate 420 g/L, sulfuric acid, The proportion of 1. 83). 200毫升/ L。 Typical treatment process is 65 ℃ 70 ℃ / 5 min10min, clean water, and dry. With chromic acid etching processing fluid has the advantage of no matter how complex, the shape of the plastic panels can handle even, its disadvantage is that operation of the danger, and have the problem of pollution.