Mitsubishi Plastics, Inc.

Mitsubishi Chemical Corporation

Makoto Inenaga

Kahoru Niimi

Takahisa Uchida

Hidejirou Yoshikawa

Masahiko Kawano

Junichi Nakamura

Shinya Fukuda

Eri Kawai

Daiki Nozawa

Ryota Yamamoto

Mitsuru Kojima

Tetsuya Yamaoka

Kazunori Inoue

Kahoru Ishii

A transparent double-sided self-adhesive sheet is provided which, when bonding to an adherend, not only excels in the ability to conform to steps or surface irregularities caused by a printing site, but also excels in workability such as cutting processability. A transparent double-sided self-adhesive sheet is proposed, having an intermediate resin layer (A) and pressure-sensitive adhesive layers (B) as front and reverse side layers, each of the layers being a layer having one or more species of (meth)acrylic acid ester series (co)polymer as the base resin, in which transparent double-sided self-adhesive sheet, the shear storage elastic modulus (G'(A)) at a frequency of 1 Hz of the intermediate resin layer (A) is higher than the pressure-sensitive adhesive layers (B) in a temperature range of 0° C. to 100° C., and, the indentation hardness (ASKER C2 hardness) of the entire sheet is 10 to 80.

Transparent double-sided self-adhesive sheet

A photocurable adhesive sheet may have both step conformability and shape stability and excellent in durability after attachment to an adhering member. Such a photocurable adhesive sheet may include a first adhesive layer, a second adhesive layer, and an intermediate layer interposed between the first and second adhesive layer. The intermediate layer may be a layer that is formed from a resin composition containing a (meth)acrylic copolymer as a main component resin and has a crosslinked structure. The first and/or second adhesive layer may be photocurable resin layers formed from a photocurable resin composition. The fall time in the measurement of holding force at 40° C. under a load of 1 N/cmmay be 60 minutes or more, while the fall time in the measurement of holding force at 60° C. under a load of 1 N/cmmay be less than 60 minutes.

Photocurable adhesive sheet, adhesive sheet laminate, laminate for image display device, and image display device

Provided is a novel transparent adhesive material having low relative permittivity as well as excellent adhesive characteristics, whereby an olefinic polymer resin layer and an acrylic polymer adhesive layer can be suitably integrated. Suggested is a transparent adhesive material provided with an outermost surface layer containing an acrylic polymer (B) and a photocrosslinking initiator, and an intermediate layer containing an olefinic polymer (A), a crosslinking agent, and a photocrosslinking initiator, in which the intermediate layer contains a (meth)acrylate monomer as the crosslinking agent.

Photocrosslinkable transparent adhesive material, transparent adhesive material layered body, and layered body for constituting optical device

A photocurable adhesive sheet that can be photocured even if there are places such as print-concealed sections that are difficult for light to reach, and even if the adhesive sheet has a certain degree of thickness, the entire sheet can be cured. A transparent adhesive sheet formed from an adhesive composition containing: (A) a thermoplastic resin; (B) a crosslinking agent; (C) a photopolymerization initiator that reacts with light having a wavelength of at least 380 to 430 nm; and (D) a wavelength conversion agent that is excited by light having a wavelength shorter than 380 nm and that emits light having a wavelength of 380 to 550 nm. The transparent adhesive sheet is characterized by the adhesive sheet absorbance X at a wavelength of 390 nm and the adhesive sheet thickness Y satisfying relational formula (1):0.5&#x2264;&#x2264;12.&#x2003;&#x2003;Formula (1):

Transparent adhesive sheet

A method for recycling optical device constituent members, wherein a transparent adhesive material is softened by heating and is crosslinked by light irradiation, an optical device constituent laminate having a constitution in which two optical device constituent members are bonded via a transparent adhesive material in a pre-crosslinked state is used as a recycle starting material, and the method including: heating at least the transparent adhesive material of the optical device constituent laminate; standing the optical device constituent laminate; hanging a linear member along an end edge of the transparent adhesive material located at an upper end edge of the optical device constituent laminate; dividing the transparent adhesive material by applying a load by the linear member; and producing the two optical device constituent members to which a divided one-side transparent adhesive material adheres.

Method for recycling optical device constituent members and method for evaluating reworkability of optical device constituent laminate

There is provided a new pressure-sensitive adhesive resin composition that can have adhesiveness to the extent of being peelable in a room temperature condition, has fluidity by hot-melting, and can finally be crosslinked to firmly bond adherends to each other. There is proposed a pressure-sensitive adhesive resin composition comprising 100 parts by mass of an acrylic copolymer (A), 0.5 to 20 parts by mass of a crosslinking agent (B), and 0.1 to 5 parts by mass of a photopolymerization initiator (C), wherein the acrylic copolymer (A) is a graft copolymer having a weight average molecular weight of 5.0&#xd7;10to 5.0&#xd7;10, contains as a trunk component of the graft copolymer a repeating unit derived from a (meth)acrylate, contains as a branch component of the graft copolymer a repeating unit derived from a macromonomer having a number average molecular weight of 5.0&#xd7;10or more and less than 6.0&#xd7;10, and contains the repeating unit derived from the macromonomer in the acrylic copolymer (A) in a proportion in a range of 0.1 to 3 mol %.

Adhesive resin composition

Provided is a novel double-sided adhesive sheet for image display device which can be bonded to the adhesion surface in close contact without space therebetween although there is a step due to printing or the like on the adhesion surface to be bonded to the adhesive sheet. The double-sided adhesive sheet for image display deviceof the invention is a sheet to bond any two adherends selected from a surface protective panel, a touch panel, and an image display panel, and the sheet is characterized in that at least one of the adherends (surface protective panel) has a stepped portionon an adhesion surfaceto adhere to the double-sided adhesive sheetand the surface shape of the bonding surfaceof the double-sided adhesive sheetto be bonded to the adhesion surfaceis shaped in accordance with the surface shape of the adhesion surface

Double-sided adhesive sheet for image display device, double-sided adhesive sheet with release film for image display device, and image display device using same

A novel transparent double-sided adhesive sheet for image display device is provided, that, under the constraint of holding down the thickness of the adhesive sheet to 250 &#x3bc;m or less, can relieve a distortion arising within the adhesive sheet after laminating even if a member has a stepped portion of 50 &#x3bc;m to 100 &#x3bc;m in height on the laminating surface. Proposed is a transparent double-sided adhesive sheet for image display device which is used for the purpose of laminating an image display device constitutive member having on a laminating surface a stepped portion of 50 &#x3bc;m to 100 &#x3bc;m in height and a flat surface portion, and another image display device constitutive member, wherein a thickness of the maximum thickness portion of the adhesive sheet is 250 &#x3bc;m or less, and a gel fraction (a) at a position in contact with a stepped portion after laminating is 10% or greater and smaller than a gel fraction (b) at a position in contact with a flat surface portion.

Transparent double-sided adhesive sheet for image display device and image display device using the same

A method for producing a laminate for configuring an image display device is provided, capable of realizing simultaneously unevenness followability and anti-bubble reliability. A method for producing a laminate for configuring an image display device is proposed, comprising the following steps (1) and (2): (1) The step of forming an adhesive composition into the form of a monolayer or a multilayer sheet, and by UV-crosslinking, primary-curing this thereby forming a pre-secondary curing transparent double-sided adhesive sheet. (2) The step of layering two image display device-constituting members via the pre-secondary curing transparent double-sided adhesive sheet and then irradiating ultraviolet light from at least a first image display device-constituting member side, UV-crosslinking through this member and secondary-curing the pre-secondary curing transparent double-sided adhesive sheet.

Method for producing laminate for configuring image display device, and image display device using the laminate

A method for producing a laminate for configuring an image display device is provided, capable of realizing simultaneously unevenness followability and anti-bubble reliability. A method for producing a laminate for configuring an image display device is proposed, comprising the following steps (1) and (2):

Provided is a novel transparent adhesive sheet with which the cut edge is not sticky over time when a laminated body that has been bonded via the adhesive sheet is cut, which can be adhered without generating residual air bubbles, even when the surface of an adherend is uneven, and which can be adhered without foaming, even when the adherend is a material such as plastic that can generate outgas. Suggested is an adhesive sheet that has one or more layers of a first adhesive layer and one or more layer of a second adhesive layer that exhibit different viscoelastic behaviors, and has an integrated structure whereby these layers are laminated, with a dynamic shear storage modulus G' of 2&#xd7;10to 5&#xd7;10Pa for G&#x2032;(20&#xb0; C.) and 1&#xd7;10to 1&#xd7;10Pa for G&#x2032;(150&#xb0; C.) when measured with a 1 Hz frequency temperature dispersion.

Transparent adhesive sheet and image display device

A novel surface protection panel is provided, with no rainbow colors appearing within the display screen or shading occurring, even when the display screen is viewed through sunglasses equipped with polarization lenses. Proposed is a surface protection panel disposed on the outer side of a liquid crystal display panel, that is to say, on the visible side of the liquid crystal display panel in a liquid crystal image display device equipped with a liquid crystal display panel. The surface protection panel has a constitution which a gas barrier transparent resin film having a gas barrier layer is layered on one side or on each side of a transparent synthetic resin plate, and the surface protection panel has a property which both the transparent synthetic resin plate and the gas barrier transparent resin film are non-stretched substantially, non-oriented or uniaxially oriented.

Growing community of inventors

Nagahama, Japan

Makoto Inenaga