# US 10,766,226 B2 · Pet release liner > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,766,226 B2 - Document ID: US10766226B2 - Status: Granted - Kind: B2 - Application number: 15/968,113 - Filed: 2018-05-01 - Published: 2019-11-07 - Granted: 2020-09-08 - Earliest claimed: 2018-05-01 - Assignees: Inteplast Group Corporation - Applicants: Inteplast Group Corporation - Inventors: George Orlych - Web page: https://patentgrep.com/patent/US10766226B2 ## CPC - B32B 7/06: permitting easy separation - E04D 5/148: {fastening by gluing} - B32B 7/12: using interposed adhesives or interposed materials with bonding properties - B32B 7/14: applied in spaced arrangements, e.g. in stripes - B32B 27/08: of synthetic resin - B32B 27/20: using fillers, pigments, thixotroping agents - B32B 27/302: {comprising aromatic vinyl (co)polymers, e.g. styrenic (co)polymers} - B32B 27/32: comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} - B32B 27/36: comprising polyesters - C09J 7/403: {characterised by the structure of the release feature} - C09J 7/405: {characterised by the substrate of the release liner} - E04D 5/06: by making use of plastics - E04D 5/10: by making use of compounded or laminated materials, e.g. metal foils or plastic films coated with bitumen - B32B 2250/05: 5 or more layers - B32B 2250/24: All layers being polymeric - B32B 2255/26: Polymeric coating - B32B 2307/4026: within the layer by addition of a colorant, e.g. pigments, dyes - B32B 2307/71: Resistive to light or to UV - B32B 2307/7242: Non-permeable - B32B 2307/7265: Non-permeable - B32B 2307/732: Dimensional properties - B32B 2307/748: Releasability - B32B 2419/06: Roofs, roof membranes - C09J 2423/006: in the substrate - C09J 2467/006: in the substrate - C09J 2483/005: in the release coating - C09J 2495/00: Presence of bitume - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - E04D: ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS (coverings of outer walls by plaster or other porous material E04F13/00) - 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) ## Abstract A multilayer release liner for use in a roofing system. that includes a roofing membrane and an asphalt or bitumen adhesive. The multilayer release liner contains a core layer including PET, surrounded by several outer layers including at least two tie layers adhered to the core layer, and at least two polyolefin layers adhered to the tie layers. The multilayer release liner of the present invention is highly compatible with silicone and does not contain any ingredients that may interfere with the adhesion or cure of a silicone coating. The liner of the present invention also provides an effective oil barrier and minimizes oil migration and discoloration of the multilayer release liner from the adhesives used in roofing systems. ## Claims ### Claim 1 A multilayer release liner for a roofing material, comprising: a core layer comprising polyethylene terephthalate (PET) having a first side and a second side; a first tie layer disposed upon the first side of the core layer and a second tie layer disposed upon the second side of the core layer; a first polyolefin layer disposed on the first tie layer and a second polyolefin layer disposed on the second tie layer; and a third polyolefin layer disposed on top of the first polyolefin layer and a fourth polyolefin layer disposed on top of the second polyolefin layer; wherein the PET is present in the core layer in an amount of at least 50 wt % based on the total weight of the core layer. ### Claim 2 (depends on 1) The multilayer release liner of claim 1, wherein the PET is present in the core layer in an amount of at least 95 wt % based on the total weight of the core layer. ### Claim 3 (depends on 1) The multilayer release liner of claim 1, wherein the core layer consists of PET. ### Claim 4 (depends on 1) The multilayer release liner of claim 1, wherein the core layer minimizes oil migration. ### Claim 5 (depends on 1) The multilayer release liner of claim 1, wherein a thickness of the core layer is within a range of about 4% to about 40% of a thickness of the multilayer release liner. ### Claim 6 (depends on 1) The multilayer release liner of claim 1, wherein a thickness of all of the tie layers combined is within a range of about 4% to about 40% of the thickness of the multilayer release liner. ### Claim 7 (depends on 1) The multilayer release liner of claim 1, wherein at least polyolefin layers further comprises an additive. ### Claim 8 (depends on 7) The multilayer release liner of claim 7, wherein the additive is selected from the group consisting of a filler, a colorant, a stabilizer, a processing agent, and an antiblocking agent. ### Claim 9 (depends on 1) The multilayer release liner of claim 1, wherein the polyolefin layers do not include a reinforcing fiber, a coupling agent, a plasticizer, a flame retardant, a peroxide, or an antistat. ### Claim 10 (depends on 1) The multilayer release liner of claim 1, wherein a thickness of all of the polyolefin layers combined is within a range of about 25% to about 50% of the thickness of the multilayer release liner. ### Claim 11 (depends on 1) The multilayer release liner of claim 1, wherein the multilayer release liner is silicone compatible. ### Claim 12 A self-adhering roofing system comprising a multilayer release liner, a roofing material, and a silicone release coating, wherein the multilayer release liner comprises: a core layer comprising polyethylene terephthalate (PET) having a first side and a second side; a first tie layer disposed upon the first side of the core layer and a second tie layer disposed upon the second side of the core layer; and a first polyolefin layer disposed on the first tie layer and a second polyolefin layer disposed on the second tie layer; wherein the PET is present in the core layer in an amount of at least 50 wt % based on the total weight of the core layer. ### Claim 13 (depends on 12) The self-adhering roofing system of claim 12, wherein the self-adhering roofing system is shelf-stable for at least 6 months at room temperature. ### Claim 14 (depends on 12) The self-adhering roofing system of claim 12, wherein the silicone release coating does not contain microparticles. ### Claim 15 (depends on 12) The self-adhering roofing system of claim 12, wherein a thickness of the silicone release coating is within the range of about 1 to about 5 microns (μm).