Coating composition for precoated steel sheet, precoated steel sheet, and process for preparing the same
US6136455A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 1998 |
| Grant date | Oct 24, 2000 |
| Priority date | — |
| Expiry date | Oct 22, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31801
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The invention relates to a thermosetting coating composition for precoated steel sheets which are required to have high hardness, good workability and stain resistance, to a precoated steel sheet having a film of the coating composition, and to a method for producing such precoated steel sheets. The coating composition for precoated steel sheets of the invention consists essentially of a polyol and contains a specific compound and a curing agent composed of polyisocyanate compounds added thereto, in which the curing agent is a mixture composed of a blocked polyisocyanate compound as obtained by blocking one or more polyisocyanate compounds selected from polyisocyanates of the following group (a) and their derivatives, and a blocked polyisocyanate compound as obtained by blocking one or more polyisocyanate compounds selected from polyisocyanates of the following group (b) and their derivatives: PA1 (a) 4,4'-diphenylmethane diisocyanate, isophorone diisocyanate, tolylene diisocyanate, xylylene diisocyanate, naphthalene-1,5-diisocyanate; PA1 (b) hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, hydrogenated 4,4'-diphenylmethane diisocyanate, hydrogenated tolylene diisoc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.