Asahi Kasei Kabushiki Kaisha

Kazuya Iseda

Hiroaki Takanohashi

Junichi Hirose

Kentaro Shiraishi

Michiyo Yamane

Mifuyu Niwa

The problem addressed by the present invention is to provide an antifogging coating film having excellent antifogging property, antifogging persistence, persistence of appearance, and elution resistance. The coating film according to the present invention contains a metal oxide (A) and a hydrophilic compound (B); the height of the eluate by a coating film surface elution test is 1.0 &#x3bc;m or less; this test is carried out by placing 10 &#x3bc;L of deionized water on the coating film, allowing the film to stand for 24 hours in a 23&#xb0; C., 50% RH environment, measuring the eluate height of 20 locations selected randomly within a 10 cmrange on the coating film surface, and determining the maximum height; and the water contact angle measured after subjecting the coating film to a moisture resistance test by exposure for 24 hours in an 85&#xb0; C., 85% RH environment followed by standing for one hour in a 23&#xb0; C., 50% RH environment, is less than 40&#xb0;. Preferably, the elution level per coating film unit volume by a coating film total elution test is 40 mg/cmor less, and this test is carried out by immersing the coating film in 23&#xb0; C. deionized water for 24 hours, then measuring the weight of the coating film eluate recovered from the deionized water.

High-durability antifogging coating film and coating composition

The present invention pertains to a coating film, and more particularly, to an antifogging coating film having excellent antifogging properties, ability to retain antifogging properties, and water resistance. The coating film according to the present invention contains a metal oxide (A) and a hydrophilic compound (B), wherein the elemental concentration ratio (C1s/M), which is between the element C and a metal element and which is obtained from a metal (M) spectrum derived from the metal oxide and a C1s spectrum in an elemental analysis of the surface using XPS, is within the range of 0.2-10. The relative elemental concentration of the element C obtained from a C1s spectrum derived from carbon-oxygen bonds and/or carbon-nitrogen bonds in elemental analysis of the surface using XPS may be within the range of 5-50 atomic %. The metal oxide may be colloidal silica. The coating film according to the present invention can be particularly preferably used as an antifogging coating film and a coating film for automotive exterior parts.

Growing community of inventors

Tokyo, Japan

Kazuya Iseda