# US 12,109,783 B2 · Intermediate film for laminated glass, and laminated glass > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,109,783 B2 - Document ID: US12109783B2 - Status: Granted - Kind: B2 - Application number: 17/623,011 - Filed: 2019-11-20 - Published: 2022-09-15 - Granted: 2024-10-08 - Earliest claimed: 2019-07-02 - Assignees: Sekisui Chemical Co., Ltd. - Applicants: Sekisui Chemical Co., Ltd. - Inventors: Yuuma Takeda; Tatsuya Iwamoto; Yuki Ishikawa; Shinji Kawada - Web page: https://patentgrep.com/patent/US12109783B2 ## CPC - B32B 17/10605: {Type of plasticiser} - B32B 7/022: Mechanical properties - B32B 7/12: using interposed adhesives or interposed materials with bonding properties - B32B 17/10036: {comprising two outer glass sheets} - B32B 17/10743: {containing acrylate (co)polymers or salts thereof} - B32B 17/10761: {containing vinyl acetal} - B32B 17/10935: {as a preformed layer, e.g. formed by extrusion} - B32B 27/08: of synthetic resin - B32B 27/22: using plasticisers - B32B 27/30: comprising vinyl {(co)polymers; comprising acrylic (co)polymers} - B32B 27/308: {comprising acrylic (co)polymers} - B32B 2250/03: 3 layers - B32B 2250/246: All polymers belonging to those covered by groups B32B27/32 and B32B27/30 - B32B 2250/40: Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA - B32B 2307/102: Insulating - B32B 2307/412: Transparent - B32B 2307/418: Refractive - B32B 2307/558: Impact strength, toughness - B32B 2605/006: Transparent parts other than made from inorganic glass, e.g. polycarbonate glazings - B32B 2605/08: Cars - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM ## Abstract Provided is an interlayer film for laminated glass capable of suppressing the generation of an optical strain in laminated glass, and enhancing the damping performance of laminated glass. An interlayer film for laminated glass according to the present invention is an interlayer film for laminated glass having a one-layer or two or more-layer structure, and includes a first layer containing a resin, and when the interlayer film is arranged between two sheets of clear float glass having a thickness of 2.5 mm to obtain a laminated glass X with a size of 150 mm in length and 300 mm in width, and the obtained laminated glass X is subjected to a specific measurement of optical strain, an optical strain value is 3.00 or less, whereas when the interlayer film is arranged between two sheets of clear float glass having a thickness of 2.1 mm to obtain a laminated glass Y having a size of 950 mm in length and 1500 mm in width, and the obtained laminated glass Y is subjected to a specific measurement of damping ratio, a damping ratio at a resonance frequency of 50 Hz or more and 80 Hz or less is 5.0% or more. ## Claims ### Claim 1 An interlayer film for laminated glass having a one-layer or two or more-layer structure, the interlayer film including a first layer containing a resin, when the interlayer film is arranged between two sheets of clear float glass having a thickness of 2.5 mm to obtain a laminated glass X with a size of 150 mm in length and 300 mm in width, and the obtained laminated glass X is subjected to measurement of optical strain, an optical strain value being 3.00 or less, when the interlayer film is arranged between two sheets of clear float glass having a thickness of 2.1 mm to obtain a laminated glass Y having a size of 950 mm in length and 1500 mm in width, and the obtained laminated glass Y is subjected to measurement of damping ratio, a damping ratio at a resonance frequency of 50 Hz or more and 80 Hz or less being 5.0% or more: the measurement of optical strain including: preparing an optical strain inspection apparatus including a light source unit for emitting irradiation light, a projection plane for projecting the irradiation light having penetrated a measuring object, an image inputting part that photographs the projection plane to generate a gray image, and an image processing part that detects an optical strain in a longitudinal direction and in a widthwise direction of the measuring object on the basis of a degree of variation in shading of the gray image; preparing as the measuring object, two measuring objects, namely, the laminated glass X, and a laminated glass for calibration obtained by arranging a monolayer interlayer film for calibration having a visible light transmittance of 88% between two sheets of clear float glass having a thickness of 2.5 mm; measuring an optical strain value of the laminated glass X by using the optical strain inspection apparatus that is adjusted such that the optical strain value in a condition that no measuring object is placed is 1.30, and an optical strain value of the laminated glass for calibration is 1.14; measurement conditions including an atmospheric temperature of 23° C. and a surface temperature of the measuring object of 25° C.; and of the obtained optical strain value in the longitudinal direction of the measuring object, and the obtained optical strain value in the widthwise direction of the measuring object, a smaller optical strain value being determined as an optical strain value of the measuring object, the measurement of damping ratio including: dividing a first surface of the laminated glass Y into regions such that each region has a length of 5 cm or less and a width of 5 cm or less; when a longitudinal length of the laminated glass Y is defined as L1, a widthwise length is defined as L2, and one vertex of the first surface is defined as vertex O, in the first surface of the laminated glass Y, installing an accelerometer at three positions: a position of 0.3L1 in the longitudinal direction and 0.3L2 in the widthwise direction from the vertex O, a position of 0.7L1 in the longitudinal direction and 0.5L2 in the widthwise direction from the vertex O, and a position of 0.6L1 in the longitudinal direction and 0.8L2 in the widthwise direction from the vertex O; in each of the regions, exciting a middle position in the longitudinal direction and a middle position in the widthwise direction of the region in the first surface with an impact hammer, and calculating a transfer function; and calculating a damping ratio at a resonance frequency of 50 Hz or more and 80 Hz or less according to the obtained transfer function. ### Claim 2 (depends on 1) The interlayer film for laminated glass according to claim 1, wherein the resin contained in the first layer has a molecular weight distribution ratio of weight average molecular weight to number average molecular weight of 8 or less. ### Claim 3 (depends on 1) The interlayer film for laminated glass according to claim 1, wherein the resin contained in the first layer has a glass transition temperature of 40° C. or more and 100° C. or less. ### Claim 4 (depends on 1) The interlayer film for laminated glass according to claim 1, wherein the first layer has a tan δ at a glass transition temperature of 1.2 or more. ### Claim 5 (depends on 1) The interlayer film for laminated glass according to claim 1, wherein the first layer has a tan δ at 200° ° C. of 0.5 or more. ### Claim 6 (depends on 1) The interlayer film for laminated glass according to claim 1, wherein the refractive index of the first layer is 1.470 or more and 1.510 or less. ### Claim 7 (depends on 1) The interlayer film for laminated glass according to claim 1, wherein the first layer contains a plasticizer. ### Claim 8 (depends on 1) The interlayer film for laminated glass according to claim 1 having a two or more-layer structure, the interlayer film including a second layer that is layered on a first surface of the first layer and contains a resin. ### Claim 9 (depends on 8) The interlayer film for laminated glass according to claim 8, wherein the second layer has a refractive index of 1.460 or more and 1.500 or less. ### Claim 10 (depends on 8) The interlayer film for laminated glass according to claim 8, wherein an absolute value of difference between a refractive index of the first layer and a refractive index of the second layer is 0.04 or less. ### Claim 11 (depends on 8) The interlayer film for laminated glass according to claim 8 having a three or more-layer structure, the interlayer film including a third layer that is layered on a second surface opposite to the first surface of the first layer and contains a resin. ### Claim 12 (depends on 1) A laminated glass comprising: a first lamination glass member; a second lamination glass member; and the interlayer film for laminated glass according to claim 1, the interlayer film for laminated glass being arranged between the first lamination glass member and the second lamination glass member. ### Claim 13 A laminated glass comprising: a first lamination glass member; a second lamination glass member; and an interlayer film for laminated glass having a one-layer or two or more-layer structure, the interlayer film including a first layer containing a resin, the laminated glass showing an optical strain value of 3.00 or less when subjected to measurement of optical strain, and showing a damping ratio of 5.0% or more at a resonance frequency of 50 Hz or more and 80 Hz or less when subjected to measurement of damping ratio, the measurement of optical strain including: preparing an optical strain inspection apparatus including a light source unit for emitting irradiation light, a projection plane for projecting the irradiation light having penetrated a measuring object, an image inputting part that photographs the projection plane to generate a gray image, and an image processing part that detects an optical strain in a longitudinal direction and in a widthwise direction of the measuring object on the basis of a degree of variation in shading of the gray image; preparing as the measuring object, two measuring objects, namely, the laminated glass, and a laminated glass for calibration obtained by arranging a monolayer interlayer film for calibration having a visible light transmittance of 88% between two sheets of clear float glass having a thickness of 2.5 mm; measuring an optical strain value of the laminated glass by using the optical strain inspection apparatus that is adjusted such that the optical strain value in a condition that no measuring object is placed is 1.30, and an optical strain value of the laminated glass for calibration is 1.14; measurement conditions including an atmospheric temperature of 23° C. and a surface temperature of the measuring object of 25° C.; and of the obtained optical strain value in the longitudinal direction of the measuring object, and the obtained optical strain value in the widthwise direction of the measuring object, a smaller optical strain value being determined as an optical strain value of the measuring object, the measurement of damping ratio including: dividing a first surface of the laminated glass into regions such that each region has a length of 5 cm or less and a width of 5 cm or less; when a longitudinal length of the laminated glass is defined as L1, a widthwise length is defined as L2, and one vertex of the first surface is defined as vertex O, in the first surface of the laminated glass, installing an accelerometer at three positions: a position of 0.3L1 in the longitudinal direction and 0.3L2 in the widthwise direction from the vertex O, a position of 0.7L1 in the longitudinal direction and 0.5L2 in the widthwise direction from the vertex O, and a position of 0.6L1 in the longitudinal direction and 0.8L2 in the widthwise direction from the vertex O; in each of the regions, exciting a middle position in the longitudinal direction and a middle position in the widthwise direction of the region in the first surface with an impact hammer, and calculating a transfer function; and calculating a damping ratio at a resonance frequency of 50 Hz or more and 80 Hz or less according to the obtained transfer function. ### Claim 14 (depends on 13) The laminated glass according to claim 13, wherein the resin contained in the first layer has a molecular weight distribution ratio of weight average molecular weight to number average molecular weight of 8 or less. ### Claim 15 (depends on 13) The laminated glass according to claim 13, wherein the resin contained in the first layer has a glass transition temperature of 40° C. or more and 100° ° C. or less. ### Claim 16 (depends on 13) The laminated glass according to claim 13, wherein the first layer has a tan δ at a glass transition temperature of 1.2 or more. ### Claim 17 (depends on 13) The laminated glass according to claim 13, wherein the first layer has a tan δ at 200° ° C. of 0.5 or more. ### Claim 18 (depends on 13) The laminated glass according to claim 13, wherein the first layer has a refractive index of 1.470 or more and 1.510 or less. ### Claim 19 (depends on 13) The laminated glass according to claim 13, wherein the first layer contains a plasticizer. ### Claim 20 (depends on 13) The laminated glass according to claim 13, wherein the interlayer film has a two or more-layer structure, and the interlayer film includes a second layer that is layered on a first surface of the first layer and contains a resin. ### Claim 21 (depends on 20) The laminated glass according to claim 20, wherein the refractive index of the second layer is 1.460 or more and 1.500 or less. ### Claim 22 (depends on 20) The laminated glass according to claim 20, wherein an absolute value of difference between a refractive index of the first layer and a refractive index of the second layer is 0.04 or less. ### Claim 23 (depends on 20) The laminated glass according to claim 20, wherein the interlayer film has a three or more-layer structure, and the interlayer film includes a third layer that is layered on a second surface opposite to the first surface of the first layer and contains a resin.