Hybrid Material of Crosslinked Microgel Particles Dispersed in an Adhesive

• US 20150284597A1
• Filed: 10/21/2013
• Published: 10/08/2015
• Est. Priority Date: 10/22/2012
• Status: Active Grant

• Current Assignee: Avery Dennison Corporation
• Original Assignee: Avery Dennison Corporation
• Inventors: Carty, Neal
• Granted Patent: US 9,926,470 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61L 15/585 Mixtures of macromolecular compounds
• CPC Class Codes: B32B 43/006 Delaminating
• CPC Class Codes: C08G 77/12 containing silicon bound to hydrogen C08G77/045 takes precedence
• CPC Class Codes: C08G 77/20 containing silicon bound to unsaturated aliphatic groups C08G77/045 takes precedence
• CPC Class Codes: C08L 83/00 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 Class Codes: C08L 83/04 Polysiloxanes
• CPC Class Codes: C09J 133/00 Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
• CPC Class Codes: C09J 183/04 Polysiloxanes
• CPC Class Codes: C09J 2301/302 the adhesive being pressure-sensitive, i.e. tacky at temperatures inferior to 30°C
• CPC Class Codes: C09J 2301/408 additives as essential feature of the adhesive layer
• CPC Class Codes: C09J 2301/412 presence of microspheres
• CPC Class Codes: C09J 2301/502 process for debonding adherents
• CPC Class Codes: C09J 2433/00 Presence of (meth)acrylic polymer
• CPC Class Codes: C09J 2467/005 in the release coating
• CPC Class Codes: C09J 2483/00 Presence of polysiloxane
• CPC Class Codes: C09J 5/00 Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers
• CPC Class Codes: C09J 7/22 Plastics; Metallised plastics
• CPC Class Codes: C09J 7/255 Polyesters
• CPC Class Codes: C09J 7/38 Pressure-sensitive adhesives [PSA]
• CPC Class Codes: Y10T 156/1111 Using solvent during delaminating [e.g., water dissolving adhesive at bonding face during delamination, etc.]
• CPC Class Codes: Y10T 428/1457 : Silicon
• CPC Class Codes: Y10T 428/259 : Silicic material
• CPC Class Codes: Y10T 428/2891 : including addition polymer from alpha-beta unsaturated carboxylic acid [e.g., acrylic acid, methacrylic acid, etc.] Or derivative thereof

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.

Claims

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.

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 μ

m 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 μ

m 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. The pressure sensitive composition of claim 4 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. The pressure sensitive adhesive composition of claim 1 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. The pressure sensitive adhesive composition of claim 1 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 1% by weight.

10. The pressure sensitive adhesive composition of claim 9 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. The pressure sensitive adhesive composition of claim 1 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.

19. 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.

17. (canceled)

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

20-35. -35. (canceled)

36. 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 within the pressure sensitive adhesive composition undergo at least one of a change in shape and an increase in volume and thereby reduce the adhesion between the pressure sensitive adhesive composition and the substrate; and

removing the article containing the pressure sensitive adhesive composition from the substrate.

37. The method according to claim 36 wherein the substrate is human skin.

38. The method of according to claim 36, wherein administering the debonding fluid includes at least one operation selected from the group consisting of

spraying, painting, foaming, rubbing, soaking, submerging, brushing, pouring, vapor depositing, syringing, dabbing, squirting, immersing, misting, and combinations thereof.

39. A selectively debondable article, the article comprising (i) a backing material, the backing material having a first surface and an oppositely directed second surface, and (ii) a pressure sensitive adhesive composition including a continuous first phase of a pressure sensitive adhesive matrix, and a discontinuous second phase having crosslinked silicone gel particles dispersed in the first phase 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, the pressure sensitive adhesive composition disposed on at least a portion of the first surface of the backing material.

40. The selectively debondable article according to claim 39, wherein the article further comprises a product release liner disposed on the pressure sensitive adhesive composition.

41. The article according to claim 39, wherein the backing material is selected from the group consisting of polyurethane, microporous films of polyolefin, polyester, poly(caprolactam), poly(N-vinylidene fluoride), nylon, cellulose acetate, and combinations thereof.

42. The article according to claim 39, wherein the crosslinked silicone gel particles are between 1 and 50 μ

m at their largest cross section.

43. The article according to claim 42 wherein the crosslinked silicone gel particles are between 5 and 30 μ

m at their largest cross section

44. The article according to claim 39 wherein the crosslinked silicone gel particles are at least 1% crosslinked.

45. The article according to claim 44 wherein the crosslinked silicone gel particles are at least 50% crosslinked.

46. The article according to claim 45 wherein the crosslinked silicone gel particles are at least 90% crosslinked.

47. The article according to claim 39 wherein upon exposure to a debonding agent the crosslinked silicone gel particles undergo a change in volume of between 3 and 20 times the original size of the particles.

48. The article according to claim 39 wherein upon exposure to a debonding agent the crosslinked silicone gel particles undergo a change in volume of 20 or more times the original size of the particles.

49. The article according to claim 39 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 1% by weight.

50. The article according to claim 49 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 10% by weight.

51. The article according to claim 50 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 20% by weight.

52. The article according to claim 51 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 30% by weight.

53. The article according to claim 52 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 40% by weight.

54. The article according to claim 53 wherein the proportion of the crosslinked silicone gel particles dispersed in the pressure sensitive adhesive matrix is at least 50% by weight.

55. The article according to claim 39 wherein the pressure sensitive adhesive composition comprises an acrylic polymer.

56. The article of claim 39 wherein the article is selected from the group consisting of a surface protective film or sheet, a masking film or sheet, a temporary fixing film or sheet, a non-temporary fixing film or sheet, a carrier tape, a seal tape or sheet, a label, a medical dressing, a bandage, and a drape.

57. A kit comprising:

a backing material having a first surface and an oppositely directed second surface,

a pressure sensitive adhesive composition disposed on at least a portion of the first surface of the backing material, the pressure sensitive adhesive composition adapted for selective debonding and including a pressure sensitive adhesive matrix, 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 size;

a selective liquid debonding agent for removing the adhesively applied backing material from the surface; and

a container retaining the selective debonding agent.

58. The kit of claim 57 further comprising:

a package to contain the backing material and the pressure sensitive adhesive disposed thereon, the container and the debonding agent.

59. The kit of claim 57 wherein the pressure sensitive adhesive composition of the backing material exhibits a tackiness that decreases after the selective debonding agent is applied.

60. The kit of claim 57 wherein the selective debonding agent is selected from the group consisting of hexamethyldisiloxane, silicones, perfluoroalkyl derivatives, low molecular weight oils, aqueous compositions, alkyl esters, limonene derivatives, paraffin solvents, hydrocarbon solvents, alkyl ethers, aromatic esters, surfactants, and combinations thereof.

61. The kit of claim 57 wherein the container includes a spray device.

62. The kit of claim 57 wherein the container includes a roll-on device.

63. The kit of claim 57 wherein the container includes a brush-on device.

64. The kit of claim 57 wherein the backing material is incorporated in a medical product selected from the group consisting of bandages, dressings, gauze, tape, wound closure covers, closure strips, and pads.