Hayakawa Rubber Company Limited

Tetsuya Kimura

Toshihiro Fujii

Hiroki Nii

Tsuguo Yamaoka

Syuno Suto

Fujii Toshihiro

Kimio Mori

A photopolymerizable rubber being obtained by copolymerizing four compounds consisting of a dienic liquid rubber having hydroxyl groups, an ethylenically unsaturated monomer having hydroxyl groups, a dihydric alcohol having a molecular weight of less than 2,000 and a diisocyanate compound. The photocured product of this composition has higher tensile strength and elongation than that of the prior photopolymerizable rubbers.

Photopolymerizable rubber

A splendid tentative surface protective coating which is useful in treating a surface of a substance by soldering or plating and which is peeled off easily from the surface after the treating is formed by preparing a solventless or solvent free type screen ink based on essentially an ultraviolet ray-curable rubbery elastomer, applying a coating of the ink on the surface of the substrate by screen printing or thin film coating, and curing the coating of the ink by irradiation with an ultraviolet ray. The tentative surface protective coating can reproduce exactly a pattern of a mask or screen, have a high chemical resistance and heat resistance, even if it has a thin thickness of 30 .mu.m, and have no afraid of deformation caused by heat curing, whereby a precise and shortened surface treatment of the surface of the substance can be afforded. Also, working environment is improved, and air conditioning equipment can be dispensed with owing to an absence or diminishment of an organic solvent. In addition, according to the present invention, an excellent ink composition is provided which is much suited to screen printing.

Method of forming a tentative surface protective coating

Growing community of inventors

Fukuyama, Japan

Tetsuya Kimura