Composition for preparing a release coating

Patent metadata

Field	Value
Publication number	US-12365818-B2
Application number	US-202017780542-A
Country	US
Kind code	B2
Filing date	Dec 2, 2020
Priority date	Dec 2, 2019
Publication date	Jul 22, 2025
Grant date	Jul 22, 2025

Abstract

A composition for forming a release coating is disclosed. The composition comprises (A) an organopolysiloxane comprising the reaction product of: (i) a silicone resin having a particular formula; and (ii) a cyclic siloxane; in the presence of a polymerization catalyst. The composition further comprises (B) an organopolysiloxane including an average of at least two silicon-bonded ethylenically unsaturated groups per molecule.

First claim

What is claimed is:

1. A composition for forming a release coating, said composition comprising:
(A) an organopolysiloxane comprising the reaction product of:
(i) a silicone resin having the formula
(R 1 y R 2 3-y SiO 1/2 ) x (SiO 4/2 ) 1.0 (ZO 1/2 ) w ,

wherein each R 1 is an independently selected hydrocarbyl group having from 1 to 32 carbon atoms; each R 2 is independently selected from R 1 , an alkoxy group, and a hydroxyl group; Z is independently H or an alkyl group; y is an integer from 1 to 3 and is independently selected in each siloxy unit indicated by subscript x; subscript x is from 0.05 to 0.80; and subscript w is from 0 to 3; and
(ii) a cyclic siloxane having the formula (R 1 2 SiO 2/2 ) n , where R 1 is defined above and n is an integer from 3 to 15;
in the presence of a polymerization catalyst; and

(B) an organopolysiloxane including an average of at least two silicon-bonded ethylenically unsaturated groups per molecule;
wherein the (A) organopolysiloxane has the formula
(R 1 y R 2 3-y SiO 1/2 ) x (R 1 2 SiO 2/2 ) m (SiO 4/2 ) 1.0 (ZO 1/2 ) w

where each R 1 and R 2 is independently selected and defined above, subscripts y and x are defined above, wherein subscript m is from 3 to 3,000; each Z is independently selected and defined above, and subscript w is defined above.

2. The composition of claim 1 , wherein: (i) each R1 is an independently selected alkyl group or alkenyl group; (ii) subscript y is 3; (iii) subscript x is from 0.20 to 0.80; (iv) subscript n is 4 or 5; or (v) any combination of (i) to (iv).

3. The composition of claim 1 , wherein the polymerization catalyst comprises a phosphazene base catalyst.

4. The composition of claim 1 , wherein subscript x is from 0.30 to 0.75.

5. The composition of claim 1 , wherein the (A) organopolysiloxane includes an average of at least two silicon-bonded ethylenically unsaturated groups per molecule.

6. The composition of claim 1 , further comprising a hydrosilylation-reaction inhibitor.

7. The composition of claim 1 , further comprising:
(C) an organosilicon compound including an average of at least two silicon-bonded hydrogen atoms per molecule; and
(D) a hydrosilylation-reaction catalyst.

8. The composition of claim 7 , wherein:
(i) the (C) organosilicon compound comprises an organohydrogensiloxane including an average of at least two pendent silicon-bonded hydrogen atoms per molecule;
(ii) the molar ratio of SiH to silicon-bonded ethylenically unsaturated groups is from 1:1 to 5:1; or
(iii) both (i) and (ii).

9. The composition of claim 1 , comprising the (A) organopolysiloxane in an amount of from 0.5 to 10 weight percent based on the total weight of the composition.

10. The composition of claim 1 , comprising the (B) organopolysiloxane in an amount of from 80 to 99 weight percent based on the total weight of the composition.

11. A method of preparing the composition of claim 1 , said method comprising:
reacting the (i) silicone resin and the (ii) cyclic siloxane in the presence of the polymerization catalyst to give the (A) organopolysiloxane; and
combining the (A) organopolysiloxane and the (B) organopolysiloxane to give the composition.

12. A method of forming a coated substrate, said method comprising:
applying a composition on the substrate; and
curing the composition to give a release coating on the substrate, thereby forming the coated substrate;
wherein the composition is the composition of claim 7 .

13. The method of claim 12 , wherein the substrate comprises cellulose and/or a polymer.

14. A coated substrate comprising a release coating disposed on a substrate formed in accordance with the method of claim 12 .

15. The composition of claim 1 , wherein the (i) silicone resin comprises a plurality of Q siloxy units clustered together, and wherein the (i) silicone resin is a solid.

Assignees

• Dow Silicones Corp

Inventors

• Chevalier Pierre
• Niu Zhenbin
• Ng Sze-Sze
• Grofils Sébastien
• Dehlin Lori
• Dujardin Deana
• Knott Alex
• Rich David
• Bekemeier Thomas
• Mitchell Timothy P
• Ahn Dongchan

Classifications

• C09J2483/005

  in the release coating · CPC title

• C09J2400/283

  in the substrate · CPC title

• C09J7/21

  Paper; Textile fabrics · CPC title

• C09J7/201

  characterised by the release coating composition on the carrier layer · CPC title

• C08J7/04

  Coating · CPC title