Oil-resistant optically clear adhesives

Patent metadata

Field	Value
Publication number	US-11920063-B2
Application number	US-202017453299-A
Country	US
Kind code	B2
Filing date	May 5, 2020
Priority date	May 10, 2019
Publication date	Mar 5, 2024
Grant date	Mar 5, 2024

Abstract

The present invention is an oil-resistant adhesive composition including a hydroxy alkyl (meth)acrylate having an alkyl group containing 2 to 4 carbons, a short alkyl (meth)acrylate having an alkyl group containing 6 or less carbons, and a photo-initiator. After the adhesive composition is soaked in oleic acid at room temperature for 7 days, the adhesive composition has an expansion percent of less than about 10%.

First claim

What is claimed is:

1. An oil-resistant adhesive composition consisting of:
at least 40% by weight of a hydroxy alkyl (meth)acrylate having an alkyl group containing 2 to 4 carbons;
a short alkyl (meth)acrylate having an alkyl group containing 6 or less carbons;
optionally a monomer selected from 2-ethoxyethoxyethyl acrylate, acrylamide, 2-cyanoacrylate, or tetrahydrofuryfuryl acrylate; and
a photo-initiator,
wherein after the adhesive composition is soaked in oleic acid at room temperature for 7 days, the adhesive composition has an expansion percent of less than about 10%.

2. The oil-resistant adhesive composition of claim 1 , wherein the hydroxy alkyl (meth)acrylate having an alkyl group containing 2 to 4 carbons comprises one of: 4-hydroxybutyl acrylate (4-HBA), 2-hydroxyethyl acrylate (2-HEA).

3. The oil-resistant adhesive composition of claim 1 , wherein the short alkyl (meth)acrylate having an alkyl group containing 6 or less carbons comprises one of: n-hexyl acrylate, n-butyl acrylate, cyclohexyl methacrylate (CHMA), cyclohexyl acrylate (CHA), and 2-methylbutyl acrylate.

4. The oil-resistant adhesive composition of claim 1 , wherein the oil-resistant adhesive composition is optically clear.

5. The oil-resistant adhesive composition of claim 1 , wherein the oil-resistant adhesive composition has a haze of less than about 5% after being soaked in oleic acid at room temperature for 4 hours in a 70° C. oven, removed from the oleic acid, and allowed to stand for about 5 minutes.

6. The oil-resistant adhesive composition of claim 1 , wherein the oil-resistant adhesive composition has a total solubility parameter of between about 9.9 and about 14 (cal/cm 3 ) 1/2 .

7. The oil-resistant adhesive composition of claim 1 , wherein the oil-resistant adhesive composition has a hydrogen bonding solubility parameter of between about 4.9 and about 7 (cal/cm 3 ) 1/2 .

8. The oil-resistant adhesive composition of claim 1 , wherein the oil-resistant adhesive composition has a glass transition temperature after curing of between about −25° C. and about 10° C.

9. The oil-resistant adhesive composition of claim 1 , wherein the oil-resistant adhesive composition has an adhesion of greater than about 3 N/cm using a crosshead speed of 12 inch per min, at an angle of 180 degrees.

10. The oil-resistant adhesive composition of claim 1 , further comprising a chain transfer agent.

11. An optically clear, oil-resistant adhesive composition consisting of
at least about 40 wt % a hydroxy alkyl (meth)acrylate having an alkyl group containing 2 to 4 carbons;
a short alkyl (meth)acrylate having an alkyl group containing 6 or less carbons; optionally a monomer selected from 2-ethoxyethoxyethyl acrylate, acrylamide, 2-cyanoacrylate, or tetrahydrofurfuryl acrylate; and
a photo-initiator,
wherein the oil-resistant adhesive composition has a haze of less than about 5% after being soaked in oleic acid at room temperature for 4 hours in a 70° C. oven, removed from the oleic acid, and allowed to stand for about 5 minutes.

12. The optically clear, oil-resistant adhesive composition of claim 11 , wherein the hydroxy alkyl (meth)acrylate having an alkyl group containing 2 to 4 carbons comprises one of: 4-hydroxybutyl acrylate (4-HBA), and 2-hydroxyethyl acrylate (2-HEA).

13. The optically clear, oil-resistant adhesive composition of claim 11 , wherein the short alkyl (meth)acrylate having an alkyl group containing 6 or less carbons comprises one of: n-hexyl acrylate, n-butyl acrylate, cyclohexyl methacrylate (CHMA), cyclohexyl acrylate (CHA), and 2-methylbutyl acrylate.

14. The optically clear, oil-resistant adhesive composition of claim 11 , wherein the oil-resistant adhesive composition has a total solubility parameter of between about 9.9 and about 14 (cal/cm 3 ) 1/2 .

15. The optically clear, oil-resistant adhesive composition of claim 11 , wherein the oil-resistant adhesive composition has a hydrogen bonding solubility parameter of between about 4.9 and about 7 (cal/cm 3 ) 1/2 .

16. The optically clear, oil-resistant adhesive composition of claim 11 , wherein the oil-resistant adhesive composition has a glass transition temperature after curing of between about −25° C. and about 10° C.

17. The optically clear, oil-resistant adhesive composition of claim 11 , wherein after the adhesive composition is soaked in oleic acid at room temperature for 7 days, the adhesive composition has an expansion percent of less than about 10%.

18. The optically clear, oil-resistant adhesive composition of claim 11 , wherein the oil-resistant adhesive composition has an adhesion of greater than about 3 N/cm using a crosshead speed of 12 inch per min, at an angle of 180 degrees.

19. The optically clear, oil-resistant adhesive composition of claim 11 , further comprising a chain transfer agent.

Assignees

• 3M Innovative Properties Company

Inventors

• Hao Encai
• Clapper Jason D
• Everaerts Albert I
• Ross Richard B

Classifications

• C09J4/00 Primary

  Adhesives based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond {; adhesives, based on monomers of macromolecular compounds of groups C09J183/00 - C09J183/16} · CPC title

• C08F220/1806

  C6-(meth)acrylate, e.g. (cyclo)hexyl (meth)acrylate or phenyl (meth)acrylate · CPC title

• C08F220/281

  and containing only one oxygen, e.g. furfuryl (meth)acrylate or 2-methoxyethyl (meth)acrylate · CPC title

• C09J133/066

  containing -OH groups · CPC title

• C09J133/14

  of esters containing halogen, nitrogen, sulfur or oxygen atoms in addition to the carboxy oxygen · CPC title