Hybrid material of crosslinked microgel particles dispersed in an adhesive

Patent metadata

Field	Value
Publication number	US-9926470-B2
Application number	US-201314437358-A
Country	US
Kind code	B2
Filing date	Oct 21, 2013
Priority date	Oct 22, 2012
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

A two-phase adhesive composition and selective debonding agent are described. The adhesive composition comprises a substantially continuous first phase comprising a pressure sensitive adhesive and a discontinuous second phase comprising crosslinked silicone gel microparticles. When applied, the selective debonding agent is absorbed by the gel microparticles. The gel microparticles change size or shape and facilitate debonding the adhesive from a substrate by decreasing the contact area between the adhesive and the substrate. Methods to selectively debond pressure sensitive adhesive compositions, methods of making the pressure sensitive adhesive compositions, articles that utilize the pressure sensitive adhesive composition, adhesive systems, and kits that include an article containing the pressure sensitive adhesive composition and the selective debonding agent, are also described.

First claim

What is claimed is:

1. A pressure sensitive adhesive composition adapted for selective debonding, the pressure sensitive adhesive composition comprising:
a continuous first phase comprising a pressure sensitive adhesive matrix; and
a discontinuous second phase comprising crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix with a characteristic such that upon exposure to a liquid debonding agent, the particles undergo a change in at least one of shape and volume;
wherein the silicone gel particles do not swell or change shape as a result of being exposed to aqueous solutions,
wherein the pressure sensitive adhesive matrix includes an acrylic polymer insoluble in the debonding agent.

2. The pressure sensitive adhesive composition of claim 1 wherein prior to exposure to the debonding agent, the size of the crosslinked silicone gel particles is between 1 and 50 μm at their largest cross section.

3. The pressure sensitive adhesive composition of claim 2 wherein prior to exposure to the debonding agent, the size of the crosslinked silicone gel particles is between 5 and 30 μm at their largest cross section.

4. The pressure sensitive adhesive composition of claim 1 wherein the crosslinked silicone gel particles are at least 1% crosslinked.

5. A pressure sensitive adhesive composition adapted for selective debonding, the pressure sensitive adhesive composition comprising:
a continuous first phase comprising a pressure sensitive adhesive matrix; and
a discontinuous second phase comprising crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix with a characteristic such that upon exposure to a liquid debonding agent, the particles undergo a change in at least one of shape and volume,
wherein the crosslinked silicone gel particles are at least 50% crosslinked.

6. The pressure sensitive composition of claim 5 wherein the crosslinked silicone gel particles are at least 90% crosslinked.

7. A pressure sensitive adhesive composition adapted for selective debonding, the pressure sensitive adhesive composition comprising:
a continuous first phase comprising a pressure sensitive adhesive matrix; and
a discontinuous second phase comprising crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix with a characteristic such that upon exposure to a liquid debonding agent, the particles undergo a change in at least one of shape and volume,
wherein after exposure to the debonding agent, the size of the crosslinked silicone gel particles is between 3 and 20 times the size of the particles prior to exposure to the debonding agent.

8. The pressure sensitive adhesive composition of claim 7 wherein after exposure to the debonding agent, the size of the crosslinked silicone gel particles is between 5 and 10 times the size of the particles prior to exposure to the debonding agent.

9. A pressure sensitive adhesive composition adapted for selective debonding, the pressure sensitive adhesive composition comprising:
a continuous first phase comprising a pressure sensitive adhesive matrix; and
a discontinuous second phase comprising crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix with a characteristic such that upon exposure to a liquid debonding agent, the particles undergo a change in at least one of shape and volume,
wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 1% by weight;
wherein after exposure to the debonding agent, the size of the crosslinked silicone gel particles is between 3 and 20 times the size of the particles prior to exposure to the debonding agent.

10. A pressure sensitive adhesive composition adapted for selective debonding, the pressure sensitive adhesive composition comprising:
a continuous first phase comprising a pressure sensitive adhesive matrix; and
a discontinuous second phase comprising crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix with a characteristic such that upon exposure to a liquid debonding agent, the particles undergo a change in at least one of shape and volume,
wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 10% by weight.

11. The pressure sensitive adhesive composition of claim 10 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 20% by weight.

12. The pressure sensitive adhesive composition of claim 11 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 30% by weight.

13. The pressure sensitive adhesive composition of claim 12 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 40% by weight.

14. The pressure sensitive adhesive composition of claim 13 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 50% by weight.

15. A pressure sensitive adhesive composition adapted for selective debonding, the pressure sensitive adhesive composition comprising:
a continuous first phase comprising a pressure sensitive adhesive matrix; and
a discontinuous second phase comprising crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix with a characteristic such that upon exposure to a liquid debonding agent, the particles undergo a change in at least one of shape and volume,
wherein the pressure sensitive adhesive matrix includes an acrylic polymer insoluble in the debonding agent.

16. A selectively debondable adhesive system comprising:
a pressure sensitive adhesive composition including (i) a continuous first phase having a pressure sensitive adhesive matrix, and (ii) a discontinuous second phase having crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix with a characteristic such that upon exposure to a debonding agent, the particles undergo a change in at least one of shape and volume; and
a liquid debonding agent.

17. The adhesive system of claim 16 wherein the debonding agent includes hexamethyldisiloxane.

18. The adhesive system of claim 16 wherein the debonding agent is selected from the group consisting of silicone oil, hydrocarbon oil, mineral oil, and combinations thereof.

19. A method of debonding an article containing a selectively debondable pressure sensitive adhesive composition, the method comprising:
providing an article containing a selectively debondable pressure sensitive adhesive composition including a continuous first phase having a pressure sensitive matrix and a discontinuous second phase having crosslinked silicone gel particles dispersed in the first phase, in which the article is adhesively bonded to a substrate so the adhesive composition and the substrate contact one another;
providing a liquid debonding agent that induces the crosslinked silicone gel particles to undergo at least one of a change in shape from their original shape and an increase in volume, and wherein the debonding agent will not be absorbed by or dissolve the pressure sensitive adhesive;
administering an effective amount of the liquid debonding agent to the pressure sensitive adhesive composition, whereby the crosslinked silicone gel particles with in the pressure sensitive adhesive composition undergo at least o

Assignees

• Avery Dennison Corp

Inventors

• Carty Neal

Classifications

• C09J183/04

  Polysiloxanes · CPC title

• C08L83/00

  Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon only; Compositions of derivatives of such polymers · CPC title

• C09J5/00

  Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers · CPC title

• Y10T428/259

  Silicic material · CPC title

• B32B43/006

  Delaminating · CPC title