Heat curable polysiloxane release coatings which stratify when baked and paper coated therewith
US4618657A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 11, 1985 |
| Grant date | Oct 21, 1986 |
| Priority date | — |
| Expiry date | Mar 11, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31786
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A heat curable coating composition which deposits a release coating containing a smaller proportion of silicone release material is disclosed. This composition comprises (1) an hydroxy-functional resin which is preferably a polyester resin; (2) a cross-linking agent for the polyester, such as an aminoplast resin; and (3) at least one and preferably a mixture of at least two reactive silicones which are preferably polysiloxanes. These two polysiloxanes comprise: (A) a hydrogen- or alkoxy-functional polysiloxane; and (B) an elastomeric polysiloxane reactive with the hydrogen- or alkoxy-functional polysiloxane to provide release properties. Either or both of the polysiloxanes are reactive with the hydroxy-functional resin or the cross-linking agent. Components (1), (2) and (3) are compatible in a liquid admixture which may contain a volatile inert organic solvent or which may be solvent-free. During the heat cure, the polysiloxanes in component (3) become incompatible with respect to the balance of the composition, and this causes stratification of the polysiloxanes to the surface of the cured coating when the composition is deposited upon a paper or plastic substrate and heated to cu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.