Urea-based and urethane-based pressure senstive adhesive blends

Patent metadata

Field	Value
Publication number	US-9738818-B2
Application number	US-201314495949-A
Country	US
Kind code	B2
Filing date	Mar 22, 2013
Priority date	Mar 30, 2012
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

Adhesive compositions include a blend of a non-siloxane polyurea-based polymer, a non-siloxane polyurethane-based polymer, or a blend of a non-siloxane polyurea-based and non-siloxane polyurethane-based with at least one (meth)acrylate-based pressure sensitive adhesive. The non-siloxane polyurea-based polymer or non-siloxane polyurethane-based polymer is free of free radically polymerized groups. The adhesive composition is a self-wetting, optically clear pressure sensitive adhesive. The adhesive compositions can be coated on substrates to form adhesive articles.

First claim

What is claimed is:

1. An adhesive composition comprising:
a non-siloxane polyurea-based polymer, a non-siloxane polyurethane-based polymer, or a blend of a non-siloxane polyurea-based and non-siloxane polyurethane-based polymers, wherein the non-siloxane polyurea-based polymer or non-siloxane polyurethane-based polymer is free of free radically polymerized groups; and
at least one (meth)acrylate-based pressure sensitive adhesive, wherein the (meth)acrylate-based pressure sensitive adhesive comprises a (meth)acrylate copolymer comprising at least one alkyl (meth)acrylate monomer and at least one reinforcing monomer selected from: an acidic monomer; or a basic monomer; or styrene, wherein if the reinforcing monomer is an acidic monomer it comprises 2-15 weight % of the total monomer composition of the (meth)acrylate copolymer, and
wherein the adhesive composition comprises a self-wetting, pressure sensitive adhesive.

2. The composition of claim 1 , wherein the non-siloxane polyurea-based polymer or non-siloxane polyurethane-based polymer comprises a segmented copolymer, which copolymer comprises repeating units of Formula I:

wherein:
each W is N-D or O;
each B is independently a polyvalent radical;
each D is independently selected from the group consisting of hydrogen, an alkyl group, a cycloalkyl group, a phenyl group, a group that completes a ring structure that includes B to form a heterocycle, and mixtures thereof;
each Z is independently a polyvalent radical;
each Y is independently a polyoxyalkylene;
m is an integer greater than zero; and
a is zero or an integer greater than zero.

3. The composition of claim 2 , wherein Y is selected from the group consisting of polyethylene oxide, polypropylene oxide, polytetramethylene oxide, or a combination thereof.

4. The composition of claim 2 , wherein W is N-D.

5. The composition of claim 2 , wherein a is an integer greater than zero.

6. The composition of claim 2 , wherein B is a polyalkylene or a polyoxyalkylene.

7. The composition of claim 1 , further comprising at least one plasticizer.

8. The composition of claim 7 , wherein the plasticizer has a refractive index of greater than 1.48.

9. The composition of claim 1 , wherein the (meth)acrylate-based pressure sensitive adhesive comprises a refractive index of greater than 1.48.

10. An adhesive article comprising:
a substrate with a first major surface and a second major surface; and
an adhesive composition coated on at least a portion of at least the first or second major surface of the substrate, wherein the adhesive composition comprises:
a non-siloxane polyurea-based polymer, a non-siloxane polyurethane-based polymer, or a blend of a non-siloxane polyurea-based and non-siloxane polyurethane-based polymers, wherein the non-siloxane polyurea-based polymer or non-siloxane polyurethane-based polymer is free of free radically polymerized groups; and
at least one (meth)acrylate-based pressure sensitive adhesive, wherein the (meth)acrylate-based pressure sensitive adhesive comprises a (meth)acrylate copolymer comprising at least one alkyl (meth)acrylate monomer and at least one reinforcing monomer selected from: an acidic monomer; or a basic monomer; or styrene, wherein if the reinforcing monomer is an acidic monomer it comprises 2-15 weight % of the total monomer composition of the (meth)acrylate copolymer, and
wherein the adhesive composition comprises a self-wetting, pressure sensitive adhesive.

11. The adhesive article of claim 10 wherein the substrate is the surface of an article, a tape backing, a film, a sheet, or a release liner.

12. The adhesive article of claim 11 wherein the film comprises an film selected from the group consisting of a visible mirror film, a color mirror film, a solar reflective film, a diffusive film, an infrared reflective film, an ultraviolet reflective film, a brightness enhancement film, a dual brightness enhancement film, an absorptive polarizer film, an optically clear film, a tinted film, a dyed film, a privacy film, a color filter film, an antireflective film, an antiglare film, a soil resistant film, or an antifingerprint film.

13. The adhesive article of claim 11 , wherein the film comprises a polymeric film selected from the group consisting of a stretchable film; a graphic film; a label stock film; or a transparent conductive film.

14. The adhesive article of claim 10 , wherein the substrate comprises a light guide film or substrate.

15. The adhesive article of claim 11 , wherein the release liner comprises a structured release liner.

16. A method of preparing an adhesive article comprising:
providing a first adhesive composition comprising:
a non-siloxane polyurea-based polymer, a non-siloxane polyurethane-based polymer, or a blend of non-siloxane polyurea-based and non-siloxane polyurethane-based polymers, wherein the non-siloxane polyurea-based polymer or non-siloxane polyurethane-based polymer is free of free radically polymerized groups; and
at least one (meth)acrylate-based pressure sensitive adhesive, wherein the (meth)acrylate-based pressure sensitive adhesive comprises a (meth)acrylate copolymer comprising at least one alkyl (meth)acrylate monomer and at least one reinforcing monomer selected from: an acidic monomer; a basic monomer; or styrene, wherein if the reinforcing monomer is an acidic monomer it comprises 2-15 weight % of the total monomer composition of the (meth)acrylate copolymer, to form a self-wetting, pressure sensitive adhesive;

providing a substrate with a first major surface and a second major surface; and
coating the first adhesive composition on at least a portion of at least the first or the second major surface of the substrate.

17. The method of claim 16 , wherein providing an adhesive composition comprises preparing a non-siloxane polyurea-based polymer, comprising:
providing at least one polyisocyanate;
providing at least one polyamine;
reacting the at least one polyisocyanate with the at least one polyamine to form the polyurea-based polymer.

18. The method of claim 17 , wherein the preparing the non-siloxane polyurea-based polymer comprises polymerizing in a solution containing the (meth)acrylate-based pressure sensitive adhesive.

19. The method of claim 16 , wherein providing an adhesive composition comprises preparing a non-siloxane polyurethane-based polymer comprising:
providing at least one polyisocyanate;
providing at least one polyol;
reacting the at least one polyisocyanate with the at least one polyol to form the polyurethane-based polymer.

20. The method of claim 16 , wherein the adhesive composition is prepared in a solventless process.

21. The method of claim 16 , wherein the substrate is the surface of an article, a tape backing, a film, a sheet, or a release liner.

22. The method of claim 16 , wherein coating comprises coating on both the first and second major surfaces of the substrate.

Assignees

• 3M Innovative Properties Co

Inventors

• Sherman Audrey A
• Branigan Margot A
• Noyola Joan M
• Fornof Ann R H
• Tapio Scott M
• Faraci Joseph J

Classifications

• C09J175/02

  Polyureas · CPC title

• C08G18/758

  containing two or more cycloaliphatic rings · CPC title

• C09J133/066 Primary

  containing -OH groups · CPC title

• C09J7/38

  Pressure-sensitive adhesives [PSA] · CPC title

• C08G18/5024

  containing primary and/or secondary amino groups · CPC title