US 12,421,428 B2
Aqueous acrylic pressure-sensitive adhesive composition, method of preparing the same and pressure-sensitive adhesive sheet including the same
Kum Hyoung Lee, Daejeon (KR); Seung Hun Yang, Daejeon (KR); and Yoon Jung Kim, Daejeon (KR)
Assigned to LG Chem, Ltd., Seoul (KR)
Appl. No. 17/426,029
Filed by LG Chem, Ltd., Seoul (KR)
PCT Filed Dec. 24, 2020, PCT No. PCT/KR2020/019101
§ 371(c)(1), (2) Date Jul. 28, 2021,
PCT Pub. No. WO2021/137531, PCT Pub. Date Jul. 8, 2021.
Claims priority of application No. 10-2020-0000702 (KR), filed on Jan. 3, 2020; and application No. 10-2020-0181497 (KR), filed on Dec. 23, 2020.
Prior Publication US 2022/0154051 A1, May 19, 2022
Int. Cl. C09J 133/08 (2006.01); C09J 133/10 (2006.01)
CPC C09J 133/08 (2013.01) [C09J 133/10 (2013.01)] 8 Claims
 
1. An aqueous acrylic pressure-sensitive adhesive composition, comprising:
a copolymer comprising 85 to 99% by weight of a linear alkyl acrylate, 0 to 10% by weight of an alkyl methacrylate, 0.5 to 2% by weight of an acrylate monomer comprising a hydroxy group, and 0.1 to 3% by weight of an unsaturated carboxylic acid, wherein the sum of the content of the acrylate monomer comprising a hydroxy group and the content of the unsaturated carboxylic acid is 2 to 4% by weight; and
an anionic surfactant, wherein the anionic surfactant is present in an amount of 0.01 to 5 parts by weight based on 100 parts by weight of the copolymer,
wherein the copolymer has an average particle diameter of 500 nm or less and satisfies Equation 1:
0.55≤X/Y<1.07  [Equation 1]
wherein X denotes a loop tack value (N/25 mm), and Y denotes a ball tack strength (#),
wherein the acrylate monomer comprising a hydroxy group is one or more selected from the group consisting of 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 2-hydroxyethylene glycol (meth) acrylate and 2-hydroxypropylene glycol (meth) acrylate,
wherein the unsaturated carboxylic acid is one or more selected from the group consisting of acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid and mesaconic acid,
wherein the anionic surfactant is one or more selected from the group consisting of sodium dodecyl benzene sulfonate and sodium polyoxyethylene alkyl ether sulfate, and
wherein the aqueous acrylic pressure-sensitive adhesive composition has a loop tack of 13 to 25 N/25 mm, and a ball tack strength (#) of 20 to 32.