Hot-melt pressure-sensitive adhesive

Patent metadata

Field	Value
Publication number	US-10604682-B2
Application number	US-201615274082-A
Country	US
Kind code	B2
Filing date	Sep 23, 2016
Priority date	Mar 26, 2014
Publication date	Mar 31, 2020
Grant date	Mar 31, 2020

Abstract

To provide a hot-melt pressure-sensitive adhesive which is easily coated, has a weak odor, high stability with time, and is also excellent in adhesive force retention performance from a low temperature range to a high temperature range. A hot-melt pressure-sensitive adhesive comprising: an amorphous polystyrene resin (A) having a number-average molecular weight of 50,000 or more; and a thermoplastic block copolymer (B) which is a copolymer of vinyl-based aromatic hydrocarbons and conjugated diene compounds.

First claim

The invention claimed is:

1. A hot-melt pressure-sensitive adhesive comprising:
a mixture of polymers consisting of (i) an amorphous polystyrene resin (A) having a weight-average molecular weight of 50,000 or more and (ii) a thermoplastic block copolymer (B) selected from styrene-butadiene-styrene copolymer and/or styrene-isoprene-styrene copolymer; and
a tackifier (C) which may be polymeric;
wherein the hot-melt pressure-sensitive adhesive is characterized as exhibiting an adhesive force retention rate of about 70-100 at T 1 and 75-234 at T 2 ;
wherein the adhesive force retention rate is calculated as
[(measured adhesive force at T1 or T2)×100%]/[measured adhesive force at T3],

wherein the measured adhesive force was determined with a universal tensile testing machine with a peeling speed of 300 mm/min and a peeling angle of 180° from a sample size of 25×70 mm and 2 mm thickness, equilibrated at T 1 , T 2 or T 3 for 2 hours; and then applied onto a stainless steel plate with a 2 kq roller, and
wherein T 1 is 40° C., T 2 is 0° C., and T 3 is 23° C.

2. A pressure-sensitive adhesive product obtained by coating the hot-melt pressure-sensitive adhesive according to claim 1 .

3. A hot-melt pressure-sensitive adhesive consisting essentially of
an amorphous polystyrene resin (A) having a weight-average molecular weight of 230,000 to 360,000;
a thermoplastic block copolymer (B) selected from styrene-butadiene-styrene copolymer and/or styrene-isoprene-styrene copolymer;
a tackifier (C);
a plasticizer (D); and
a stabilizer (E).

4. A hot-melt pressure-sensitive adhesive comprising:
a recycled amorphous polystyrene resin (A) having a weight-average molecular weight of 230,000 to 360,000;
a thermoplastic block copolymer (B) selected from styrene-butadiene-styrene copolymer and/or styrene-isoprene-styrene copolymer; and
a tackifier (C);
wherein the hot-melt pressure-sensitive adhesive is characterized as exhibiting an adhesive force retention rate of about 70-100 at T 1 and 75-234 at T 2 ;
wherein the adhesive force retention rate is calculated as:
[(measured adhesive force at T1 or T2)×100%]/ [measured adhesive force at T3],

wherein the measured adhesive force was determined with a universal tensile testing machine with a peeling speed of 300 mm/min and a peeling angle of 180° from a sample size of 25×70 mm and 2 mm thickness, equilibrated at T 1 , T 2 or T 3 for 2 hours; and then applied onto a stainless steel plate with a 2 kq roller, and
wherein T 1 is 40° C., T 2 is 0° C., and T 3 is 23° C.

Assignees

• Henkel Ag & Co Kgaa

Inventors

• Isobe Yukio
• Tomatsu Itsuro
• Hayakawa Tadashi

Classifications

• C09J153/02

  Vinyl aromatic monomers and conjugated dienes · CPC title

• C08L2205/035

  containing four or more polymers in a blend · CPC title

• C08L53/02

  of vinyl-aromatic monomers and conjugated dienes · CPC title

• C09J125/06 Primary

  Polystyrene · CPC title

• C09J11/08

  Macromolecular additives · CPC title