Nippon Paint Compnay, Ltd.

Other

Kazuo Nobe

Tamotsu Sobata

Takayuki Sato

Akira Ushio

Shoji Oka

Toru Shimizu

Teturo Kishimoto

Tatsuya Oguri

Keiji Maetsuji

A method of coating aluminum and aluminum alloy substrates not only imparts a corrosion resistance comparable or even superior to that afforded by chromate treatment but also improves the adhesion to the coating film, while the luster of aluminum is fully retained, notwithstanding the use of a chromium-free treating solution, resulting in an improved coated article with the coated surface having a metallic luster. The method comprises treating an aluminum or aluminum alloy substrate with an acidic solution containing sulfuric acid and 0.2 to 0.4 g/L of a ferric ion and having a pH value of 0.6 to 2.0, subjecting the same to chemical conversion treatment with an acidic coat-forming agent containing 0.01 to 0.125 g/L of a zirconium or titanium ion, 0.01 to 1.0 g/L of a phosphate ion, and 0.01 to 0.5 g/L of a fluoride ion and having a pH value of 1.5 to 4.0, followed by coating.

Method of coating aluminum and aluminum alloy substrates and coated articles

It is required to undergo painting pretreatment of a plastic formings by a method which is replaceable of a vapor-washing method using a chlorinated hydrocarbon in order to prevent from the environmental destruction by the chlorinated hydrocarbon. A plastic formings is brought in contact and treated with a treating solution prepared by suspending a hydrocarbons solvent in water. A plastic formings is brought in contact and treated with a treating solution containing an alkali component and then, said treating solution attaching on the surface of said formings is rinsed out and, in at least a final stage of the rinsing-out, the surface of said formings is brought in contact with a surface-conditioning solution which contains a nonionic surface-active agent having the HLB value of 10 to 17 in a concentration range of 0.001 to 100 g/l.

Method for painting pretreatment of plastic formings and cleaner for

Zinc phosphate coating solution contains phosphate ions in an amount of at least 0.5 percent by weight and in the phosphate ion to nitrate ion molar weight ratio of from 1 : 0.7 to 1 : 1.3. This solution also contains zinc ions in an amount, preferably, of at least 0.03 percent by weight and in a ratio of zinc ion to phosphate ion of less than 0.116 to 1. Nickel ions may be added in an amount of at least 0.01 percent by weight and in the nickel ion to zinc ion ratio of less than 1.89 to 1. The pH value of this solution ranges from about pH 3.3 to pH 3.8, whereby the consumption of nitrites employed as accelerators is reduced and sludges are formed in less amounts as in the form easily removable from an apparatus where the phosphating is effected. The zinc phosphate coating solution is preferably employed for an apparatus in which little or no solution is discharged out of the phosphating system.

Zinc phosphate coating process

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Kyoto, Japan

Kazuo Nobe