Tacky resin composition and pressure-sensitive adhesive film or sheet

• US 8,497,321 B2
• Filed: 01/28/2009
• Issued: 07/30/2013
• Est. Priority Date: 02/05/2008
• Status: Expired due to Fees

• Current Assignee: Du Page Medical Group Limited
• Original Assignee: Du Page Medical Group Limited
• Inventors: Aoyama, Masataka, Hironaka, Yoshitaka, Gonohe, Hisao
• Primary Examiner(s): MULLIS, JEFFREY C
• Application Number:
  US12/866,106
• Publication Number:
  US 20100317802A1
• Time in Patent Office: 1,644 Days
• Field of Search: 525/93, 525/95, 525/98
• US Class Current: 525/93
• CPC Class Codes: C08L 23/0853 Vinylacetate
• CPC Class Codes: C08L 23/10 Homopolymers or copolymers of propene
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 53/02 of vinyl-aromatic monomers and conjugated dienes
• CPC Class Codes: C09J 2203/306 for protecting painted surfaces, e.g. of cars
• CPC Class Codes: C09J 2423/00 Presence of polyolefin
• CPC Class Codes: C09J 2453/00 Presence of block copolymer
• CPC Class Codes: C09J 7/22 Plastics; Metallised plastics
• CPC Class Codes: C09J 7/38 Pressure-sensitive adhesives [PSA]
• 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 tacky resin composition which has proper initial tackiness, is sufficiently inhibited from rising in tackiness with time, can keep tackiness at a proper range even when it receives a slight heat history or is stored for a long time, has very small dependence on peeling speed, and can provide high transparency to a pressure-sensitive adhesive film or sheet as required, and a pressure-sensitive adhesive film or sheet for the surface protection of an article, which is obtained form the tacky resin composition. The tacky resin composition comprises (A) 5 to 80 parts by weight of an olefin polymer (component A), (B) 5 to 80 parts by weight of an ethylene/unsaturated ester copolymer (component B) and (C) 1 to 60 parts by weight of a styrene-based elastomer and/or an olefin-based elastomer (component C) based on 100 parts by weight of the total of the components A, B and C.

Claims

1. A tacky resin composition consisting of:

(A) 15 to 75 parts by weight of an only one olefin polymer (component A) selected from a group consisting of low-density polyethylene, high-density polyethylene, polypropylene random copolymer, and isotactic polypropylene,

(B) 15 to 60 parts by weight of an ethylene/unsaturated ester copolymer (component B),

(C) 1 to 49 parts by weight of a styrene-based elastomer and/or an olefin-based elastomer (component C),

optionally 0.5 to 20 parts by weight of a tackifier, based on 100 parts by weight of the total of the components A, B and C, the tackifier being selected from a group consisting of ethylene/unsaturated carboxylic acid copolymer resins, ethylene/unsaturated carboxylic acid/unsaturated carboxylate copolymer resins, and polyester resins, and

optionally an antioxidant, ultraviolet absorbent, optical stabilizer, pigment, or combinations thereof.

2. The tacky resin composition according to claim 1, wherein (A) the content of the olefin polymer (component A) is 30 to 75 parts by weight, (B) the content of the ethylene/unsaturated ester copolymer (component B) is 30 to 60 parts by weight, (C) the content of the styrene-based elastomer and/or the olefin-based elastomer (component C) is 1 to 49 parts by weight based on 100 parts by weight of the total of the components A, B and C.

3. The tacky resin composition according to claim 1, wherein the component A is a propylene-based (co)polymer having a melting point of 130°

C. or higher.

4. The tacky resin composition according to claim 1, wherein the polypropylene random copolymer comprises not less than 50 mol % a propylene component and less than 50 mol % of α

-olefins having 2 or 4 to 20 carbon atoms.

5. The tacky resin composition according to claim 1, wherein the styrene-based elastomer is a styrene-ethylene/butene-styrene block copolymer (SEBS) which is a hydrogenated product of a styrene-butadiene-styrene block copolymer (SBS) or a styrene-ethylene/propylene-styrene block copolymer (SEPS) which is a hydrogenated product of a styrene-isoprene-styrene block copolymer (SIS).

6. The tacky resin composition according to claim 1 which consists of 0.5 to 20 parts by weight of the tackifier.

7. A pressure-sensitive adhesive film or sheet comprising a pressure-sensitive adhesive layer formed from the tacky resin composition of claim 1.

8. A pressure-sensitive adhesive film or sheet which comprises a pressure-sensitive adhesive layer formed from the tacky resin composition of claim 1.

9. A pressure-sensitive adhesive film or sheet having a pressure-sensitive adhesive layer formed from the tacky resin composition of claim 1 on at least one side of a base layer.

10. The pressure-sensitive adhesive film or sheet according to claim 9, wherein the base layer is a film or sheet made of an ethylene-based polymer or a propylene-based polymer.

11. A surface protection film or sheet which is the film or sheet of claim 9.

12. A method of protecting a surface of an article, comprising:

attaching the pressure-sensitive adhesive film or sheet of claim 7 onto the surface of an article.

13. A tacky resin composition consisting of:

7.5 to 75 parts by weight of an only one olefin polymer (component A) selected from a group consisting of low-density polyethylene, high-density polyethylene, polypropylene random copolymer, and isotactic polypropylene,

7.5 to 75 parts by weight of an ethylene/unsaturated ester copolymer (component B),

1 to 49 parts by weight of a styrene-based elastomer and/or an olefin-based elastomer (component C),

optionally 0.5 to 20 parts by weight of a tackifier based on 100 parts by weight of the total of the components A, B and C, the tackifier being selected from a group consisting of ethylene/unsaturated carboxylic acid copolymer resins, ethylene/unsaturated carboxylic acid/unsaturated carboxylate copolymer resins, and polyester resins, and

optionally an antioxidant, ultraviolet absorbent, optical stabilizer, pigment, or combinations thereof.

14. The tacky resin composition of claim 13, wherein the composition consists of 30 to 75 parts by weight of the olefin polymer (component A), 30 to 60 parts by weight of the ethylene/unsaturated ester copolymer (component B), 1 to 49 parts by weight of the styrene-based elastomer and/or the olefin-based elastomer (component C), and optionally an antioxidant, ultraviolet absorbent, optical stabilizer, pigment, or combinations thereof.

15. The tacky resin composition of claim 13, wherein the composition consists of 15 to 75 parts by weight of the isotactic olefin polymer (component A), 15 to 60 parts by weight of the ethylene/unsaturated ester copolymer (component B), and 1 to 49 parts by weight of the styrene-based elastomer and/or the olefin-based elastomer (component C).

16. The tacky resin composition of claim 13, wherein the composition consists of 15 to 75 parts by weight of the isotactic olefin polymer (component A), 15 to 60 parts by weight of the ethylene/unsaturated ester copolymer (component B), and 1 to 49 parts by weight of the olefin-based elastomer (component C).

17. The tacky resin composition of claim 13, wherein the composition consists of 15 to 75 parts by weight of the olefin polymer (component A), 15 to 60 parts by weight of the ethylene/unsaturated ester copolymer (component B), and 1 to 49 parts by weight of a crystalline olefin-amorphous olefin-crystalline olefin block copolymer (component C).

18. The tacky resin composition of claim 13, wherein the composition consists of 15 to 75 parts by weight of the olefin polymer (component A), 15 to 60 parts by weight of the ethylene/unsaturated ester copolymer (component B), and 1 to 49 parts by weight of a crystalline ethylene-amorphous ethylene/butene-crystalline ethylene block copolymer (component C).

19. The tacky resin composition of claim 13, wherein the composition consists of 15 to 75 parts by weight of the olefin polymer (component A), 15 to 60 parts by weight of the ethylene/unsaturated ester copolymer (component B), and 1 to 49 parts by weight of a styrene-ethylene/propylene-styrene block copolymer and/or a styrene-ethylene/butene-styrene block copolymer (component C).

20. The tacky resin composition of claim 13, wherein the composition consists of 30 to 75 parts by weight of the olefin polymer (component A), 30 to 60 parts by weight of the ethylene/unsaturated ester copolymer (component B), and 1 to 49 parts by weight of the styrene-based elastomer and/or the olefin-based elastomer (component C).