Nippon Paint Compnay, Ltd.

Seiichiro Shirahata

Tamotsu Sobata

Akio Tokuyama

Shoji Shiraishi

Mitsuo Shinomiya

Satoshi Miyamoto

Yutaka Ohashi

Hideaki Morita

Toshiko Nakazawa

Hiroshi Chihara

Syoji Shiraishi

Toshiyuki Kawashima

Naoki Tada

The invention provides a surface conditioner which can prevent an aluminum alloy from stray current corrosion in chemical conversion treatment and reduce the difference between contact and noncontact areas in conversion coating build-up on an aluminum alloy and which enables the formation of excellent chemical conversion coatings on various metal materials and a surface conditioner which can prevent metal from rusting after surface conditioning and is excellent in dispersion stability in a treating bath. A surface conditioner to be applied prior to the phosphating of metal which contains (A) zinc phosphate particles having Dof 3 &#x3bc;m or below, (B) a water-soluble organic polymer, and (C) a layer clay mineral and has a pH of 3 to 12, characterized by further containing as the function imparting agent (D) a di- or tri-valent metal nitrite, zinc oxide and/or sodium hydroxide, or a nonionic or anionic surfactant.

Surface conditioner and surface conditioning method

Method for recovery of aqueous wash in phosphate chemical conversion and apparatus for metal surface treatment

The present invention provides a highly durable surface-conditioning agent for use in a pretreatment step for a phosphate coating treatment of metallic materials, which is an aqueous solution comprising 1 to 50 ppm of titanium ion, 50 to 1,000 ppm or phosphate ion, 50 to 400 ppm of tripolyphosphate ion and 20 to 1,500 ppm of carbonate ion, with a tripolyphosphate ion/titanium ion weight ratio of 10 to 100, and having a pH of 8.5 to 10.0.

Highly durable surface-conditioning agent

A solution which is stored in a treatment bath is stirred by vibration stirring means provided in the treatment bath in a range of receiving a metal molded article or around a substantially horizontal surface of the metal molded article so that mean acceleration a expressed in the following equation is at least 8 cm/sec.sup.2 : ##EQU1## where X, Y and Z, which are in units of cm/sec.sup.2, represent average acceleration values of flow rate changes within 60 seconds, measured simultaneously in three axial directions of X, Y and Z which are perpendicular to each other at a measuring position.

Pretreatment method for coating on molded metal article

To treat an iron-based, zinc-based, and an aluminumbased surfaces etc. with zinc phosphate using the same solution, a treating solution is adjusted in concentrations so as to contain a simple fluoride in a range of 200.about.500 mg/l upon converting into a HF concentration and to contain a fluoride complex in a range shown in the following formula; ##EQU1## and also, it is adjusted in an active fluorine concentration so as to be 15.about.130 .mu.A at a value indicated by a silicon electrode meter. Instead of such adjusting, aluminum ions in the treating solution is precipitated in an outside of a treating bath to separate them from the treating solution and then, this treating solution may be returned in to the treating bath.

Method for phosphating metal surface with zinc phosphate

To treat an iron-based, zinc-based, and an aluminum-based surfaces etc. with zinc phosphate using the same solution, a treating solution is adjusted in concentrations so as to contain a simple fluoride in a range of 200.about.500 mg/l upon converting into a HF concentration and to contain a fluoride complex in a range shown in the following formula; ##EQU1## and also, it is adjusted in an active fluorine concentration so as to be 15.about.130 .mu.A at a value indicated by a silicon electrode meter. Instead of such adjusting aluminum ions in the treating solution is precipitated in an outside of a treating bath to separate them from the treating solution and then, this treating solution may be returned into the treating bath.

Growing community of inventors

Tokyo, Japan

Seiichiro Shirahata