# US 5,705,551 A · Elastomeric pressure-sensitive adhesive compositions exhibiting good cutting performance > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,705,551 A - Document ID: US5705551A - Status: Granted - Kind: A - Application number: 08/262,751 - Filed: 1994-06-20 - Granted: 1998-01-06 - Earliest claimed: 1991-12-06 - Assignees: Avery Dennison Corporation - Inventors: Yukihiko Sasaki; Jesse C. Ercillo - Web page: https://patentgrep.com/patent/US5705551A ## CPC - C09J 153/02: Vinyl aromatic monomers and conjugated dienes - C09J 7/387: {Block-copolymers} - C08L 2666/02: Organic macromolecular compounds, natural resins, waxes or and bituminous materials - C09J: ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES (preparation of glue or gelatine C09H) - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) ## Abstract The cuttability of elastomeric pressure-sensitive adhesives, particularly of hot-melt tackified mutually immiscible elastomers, is improved by the addition of surfactants containing polyethylene-oxide and polypropylene-oxide blocks. ## Claims ### Claim 1 A pressure-sensitive adhesive exhibiting improved cuttability as an element of a pressure-sensitive label construction which pressure-sensitive adhesive comprises an elastomeric hot melt pressure-sensitive adhesive formed of a first elastomer providing a first polymerized diene component exhibiting a first glass transition temperature and a second elastomer providing a second polymerized diene component exhibiting a second glass transition temperature greater than the first glass transition temperature, and a tackifying additive comprising at least one tackifier which is preferentially soluble in the second elastomer and present in an amount sufficient to cause the dynamic mechanical spectrum of the mixture of immiscible elastomers to exhibit an increase in the second glass transition temperature and an increase in the difference between the first and second glass transition temperatures and an increase in the value of tangent delta determined at the second glass transition temperature, and in which the elastomers are present in an amount of from about 20 to 50% by weight of elastomers and tackifying additive, said pressure sensitive adhesive containing a surfactant having an HLB value greater than 7 comprised of at least one hydrophilic polyethylene oxide block and at least one hydrophobic propropylene oxide block and from 0 to about 15% by weight of the composition of a compatible wax. ### Claim 2 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the surfactant is selected from the group consisting of compounds of the formula: PEO--PPO--PEO, PPO--PEO--PPO, ##STR2## and mixtures thereof wherein PEO means a polyethylene-oxide block and PPO means a polypropylene-oxide block, said surfactant having an HLB value of at least about 7. ### Claim 3 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the surfactant is present in an amount of from about 1 to about 6% by weight of the surfactant and elastomeric pressure-sensitive adhesive. ### Claim 4 (depends on 2) A pressure-sensitive adhesive as claimed in claim 2 in which the surfactant is present in an amount of from about 1 to about 6% by weight of the surfactant and elastomeric pressure-sensitive adhesive. ### Claim 5 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the wax is a polyethylene glycol wax. ### Claim 6 (depends on 2) A pressure-sensitive adhesive as claimed claim 2 in which the wax is a polyethylene glycol wax. ### Claim 7 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the first elastomer is selected from the group consisting of polybutadiene, styrene-butadiene block copolymers, styrene-butadiene-styrene block copolymers, styrene-butadiene multiarmed block copolymers and mixtures thereof, the second elastomer is selected from the group consisting of natural rubber, synthetic polyisoprene, styrene-isoprene-styrene block copolymers, styrene-isoprene block copolymers, styrene-isoprene multiarmed block copolymers and mixtures thereof, and the tackifying system is preferentially soluble in the polyisoprene component and selected from the group comprising normally solid polymerized C.sub.5 or C.sub.6 diene resins, normally solid hydrogenated aromatic hydrocarbons, normally solid saturated cycloaliphatic hydrocarbons and mixtures thereof, alone or in combination with a normally liquid polymerized C.sub.5 or C.sub.6 diene tackifier, a plasticizing oil and mixtures thereof. ### Claim 8 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the first elastomer is selected from the group consisting of polybutadiene, styrene-butadiene block copolymers, styrene-butadiene-styrene block copolymers, styrene-butadiene multiarmed block copolymers and mixtures thereof, the second elastomer is selected from the group consisting of natural rubber, synthetic polyisoprene, styrene-isoprene-styrene block copolymers, styrene-isoprene block copolymers, styrene-isoprene multiarmed block copolymers and mixtures thereof, and the tackifying system is preferentially soluble in the polyisoprene component and selected from the group comprising normally solid polymerized C.sub.5 or C.sub.6 diene resins, normally solid hydrogenated aromatic hydrocarbons, normally solid saturated cycloaliphatic hydrocarbons and mixtures thereof, alone or in combination with a normally liquid polymerized C.sub.5 or C.sub.6 diene tackifier, a plasticizing oil and mixtures thereof. ### Claim 9 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the weight ratio of the first elastomer to the second elastomer is about 0.5 to about 5. ### Claim 10 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the weight ratio of the first elastomer to the second elastomer is about 0.5 to about 1. ### Claim 11 (depends on 8) A pressure-sensitive adhesive as claimed in claim 8 in which the weight ratio of the first elastomer to the second elastomer is about 0.5 to about 5. ### Claim 12 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the weight ratio of the first elastomer to the second elastomer is at about 1.0 to about 1.5. ### Claim 13 (depends on 8) A pressure-sensitive adhesive as claimed in claim 8 in which the weight ratio of the first elastomer to the second elastomer is about 1.0 to about 1.5. ### Claim 14 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which a first and second elastomer are present in an amount of from about 30% to 50% by weight based on the total weight of the mixture and tackifying system. ### Claim 15 (depends on 8) A pressure-sensitive adhesive as claimed in claim 8 in which a first and second elastomer are present in an amount of from about 30% to 50% by weight based on the total weight of the mixture and tackifying system. ### Claim 16 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the weight ratio of the first elastomer to the second elastomer is about 1.3:1. ### Claim 17 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the weight ratio of the first elastomer to the second elastomer is about 0.5:1 to about 2.5:1. ### Claim 18 (depends on 2) A pressure-sensitive adhesive as claimed in claim 2 in which the weight ratio of the first elastomer to the second elastomer is about 0.5:1 to about 1.5:1. ### Claim 19 (depends on 16) A pressure-sensitive adhesive as claimed in claim 16 in which the weight ratio of the first elastomer to the second elastomer is about 0.5:1 to about 1.5:1. ### Claim 20 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the surfactant has an HLB value of at least 12. ### Claim 21 (depends on 2) A pressure-sensitive adhesive as claimed in claim 2 in which the surfactant has an HLB value of at least 12. ### Claim 22 (depends on 1) A pressure-sensitive adhesive as claimed in claim 1 in which the surfactant has an HLB value greater than 24. ### Claim 23 (depends on 2) A pressure-sensitive adhesive as claimed in claim 2 in which the surfactant has an HLB value greater than 24. ### Claim 24 A pressure-sensitive adhesive exhibiting improved cuttability as an element of a pressure-sensitive label construction which pressure-sensitive adhesive comprises an elastomeric hot melt pressure-sensitive adhesive formed of a first elastomer providing a first polymerized diene component which is a polybutadiene, said first elastomer exhibiting a first glass transition temperature and a second elastomer providing a second polymerized diene which is a polyisoprene, said second elastomer component exhibiting a second glass transition temperature greater than the first glass transition temperature, and a tackifying additive comprising at least one tackifier which is preferentially soluble in the second elastomer and present in an amount sufficient to cause the dynamic mechanical spectrum of the mixture of immiscible elastomers to exhibit an increase in the second glass transition temperature and an increase in the difference between the first and second glass transition temperatures and an increase in the value of tangent delta determined at the second glass transition temperature, and in which the elastomers are present in an amount of from about 20 to 50% by weight of elastomers and tackifying additive, said pressure sensitive adhesive containing a surfactant having an HLB value greater than 7 and comprised of at least one hydrophilic polyethylene oxide block and at least one hydrophobic propropylene oxide block and from 0 to about 15% by weight of the composition of a compatible wax. ### Claim 25 (depends on 24) A pressure-sensitive adhesive as claimed in claim 24 in which the surfactant has an HLB value of at least 12.