Tacky resin composition and pressure-sensitive adhesive film or sheet
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.
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).