Compositions and processes for providing release coatings
An aqueous composition that can be used to provide a release release properties to adhesive tape substrates can be applied at coating weights far less than those required in previously available compositions containing the same or similar release polymers. Inclusion of small amounts of a superwetter results in improved coatability and reduced amounts of sound generated during the process of releasing an adhesive tape from its roll.
1. An aqueous composition for release coatings, the aqueous composition having a total solids content of no more than 10 weight percent and comprising:
a) a release polymer component that is free of silicone release polymers and that comprises a release polymer from a monomer of formula (I-a) and which has a weight average molecular weight of 125+75 kg/mol,
where R 1 is H, X is O, R 2 is lower alkyl, E is O and R 3 is a long chain alkyl group, where the release polymer includes pendent groups of formula (I)
where X is O or S, E is O or S or NH, R 2 is a lower alkyl, Z is a divalent (thio) carbonyl-containing group that further includes two additional heteroatoms bonded to the carbon atom of the (thio) carbonyl, and R 3 is a long chain alkyl group; and
b) from 0.75 to 1.25 weight percent, relative to the composition, of dioctyl sulfosuccinate.
2. The aqueous composition of claim 1 having total solids content of no more than 8 weight percent.
3. The aqueous composition of claim 1 wherein each release polymer has a weight average molecular weight of 125+25 kg/mol.
4. A process for providing a release coating to an article, the method comprising applying to a substrate the aqueous composition of claim 1 .
5. An article comprising a substrate coated with the aqueous composition of claim 1 .
6. The article of claim 5 , further comprising an adhesive layer.