Nitto-Denko Corporation

Toyo Boseki Kabushiki Kaisha

Nitto Electric Industrial Co., Ltd.

Nitto Denki Corporation

Hitoshi Takahira

Satomi Yoshie

Takao Yoshikawa

Masahiro Ohura

Shigeki Muta

Masahiro Oura

Miki Tanimura

Hiroshi Yamamoto

Seiji Umemoto

Kazuhito Hosokawa

Shigeki Ishiguro

Hiroaki Kishioka

Hiroki Senda

Shuji Yano

Kiyoshi Saito

Yuka Sekiguchi

Naoyuki Nishiyama

Katsuya Shimeno

Rie Hayashiuchi

Asuka Endo

Kazuyuki Kitakura

Kazuhiro Tajiri

Tadashi Nakajima

Michio Kohmoto

Daiki Funaoka

The present invention provides a pressure-sensitive adhesive sheet containing a pressure-sensitive adhesive layer that contains a polyester resin as a main component, in which the pressure-sensitive adhesive layer having a laminate structure that contains at least one layer LA where a polyester resin Ehaving Mw of from 4&#xd7;10to 12&#xd7;10is crosslinked and at least one layer LB where a polyester resin Ehaving Mw of from 0.2&#xd7;10to 1&#xd7;10is crosslinked, and at least one surface of the pressure-sensitive adhesive layer is constituted by the layer LA.

Adhesive sheet

Efficiently produced is a release liner including a plant-derived film as a substrate and having a good appearance, releasability, and adhesion. A method according to the present invention produces a release liner having a plant-derived film substrate and, on at least one side thereof, a release coat layer derived from a thermosetting silicone resin. The method includes the steps as follows:

Method for producing release liner

The present invention has an object to provide a solvent-free polyester-based adhesive composition having good coatability and capable of forming an adhesive that shows good adhesion performance. The present invention provides a polyester-based adhesive composition containing a polyester having Mw of from 1&#xd7;10to 20&#xd7;10as a main component and a trifunctional or more polyepoxy compound as a crosslinking agent, and containing substantially no organic solvent. The molar number, m, of hydroxyl group contained in a polyalcohol component constituting the polyester is from 0.5 to 0.98 times of the molar number, m, of carboxyl group contained in a polycarboxylic acid component. The composition has a viscosity at 23&#xb0; C. of at most 80 Pa&#xb7;s.

Polyester adhesive composition

The present invention provides a polyester, a polyester composition and a pressure-sensitive adhesive composition capable of obtaining a pressure-sensitive adhesive which is global-environmentally friendly and is excellent in pressure-sensitive adhesion properties, using a plant-derived raw material; and a pressure-sensitive adhesive layer and a pressure-sensitive adhesive sheet which can be obtained by using the same. A polyester of the present invention is a polyester comprising at least a lactic acid unit, a dibasic acid unit and a glycol unit, wherein the dibasic acid unit contains dimer acid, and the polyester has a glass transition temperature as measured at a temperature rising rate of 20&#xb0; C./minute using a differential scanning calorimeter, of &#x2212;70 to &#x2212;20&#xb0; C., a weight average molecular weight of 20,000 to 300,000 and a hydroxyl value of 1 to 100 mgKOH/g.

Polyesters, polyester compositions, pressure-sensitive adhesive compositions, pressure-sensitive adhesive layers and pressure-sensitive adhesive sheets

A thermally removable pressure-sensitive adhesive sheet includes a substrate and a pressure-sensitive adhesive layer that is provided on at least one side of the substrate and made from a polyester-based pressure-sensitive adhesive composition containing a polyester including at least a lactic acid unit, a dibasic acid unit, and a glycol unit, a foaming agent, and a crosslinking agent. The dibasic acid unit includes a dimer acid, the polyester has a weight average molecular weight of 20,000 to 200,000 and a glass transition temperature of &#x2212;70 to &#x2212;20&#xb0; C. as measured using a differential scanning calorimeter at a temperature rise rate of 20&#xb0; C./minute, and the polyester has a hydroxyl value of 1 to 60 mgKOH/g.

Thermally removable pressure-sensitive adhesive sheet

A surface-protecting pressure-sensitive adhesive sheet includes: a substrate; and a pressure-sensitive adhesive layer that is provided on at least one side of the substrate and made from a polyester-based pressure-sensitive adhesive composition containing a crosslinking agent and a polyester including at least a lactic acid unit, a dibasic acid unit, and a glycol unit. The dibasic acid unit includes a dimer acid, the polyester has a weight average molecular weight of 20,000 to 200,000 and a glass transition temperature of &#x2212;70 to &#x2212;20&#xb0; C. as measured using a differential scanning calorimeter at a temperature rise rate of 20&#xb0; C./minute, the polyester-based pressure-sensitive adhesive composition has a hydroxyl value of 20 to 60 mgKOH/g, and the pressure-sensitive adhesive layer has a gel fraction of 85 to 99% by weight.

Pressure-sensitive adhesive sheet for surface protection

A radiation-cure removable type pressure-sensitive adhesive sheet includes: a pressure-sensitive adhesive layer made from a polyester-based pressure-sensitive adhesive composition containing a polyester including at least a lactic acid unit, a dibasic acid unit, and a glycol unit, a radiation-cure resin, a radiation reaction initiator, and a crosslinking agent. The dibasic acid unit includes a dimer acid, the polyester has a glass transition temperature of &#x2212;70 to &#x2212;20&#xb0; C., a weight average molecular weight of 20,000 to 200,000, and a hydroxyl value of 1 to 60 mgKOH/g, the composition contains 30 to 70 parts by weight of the radiation-cure resin based on 100 parts by weight of the polyester and contains 3 to 10% by weight of the radiation reaction initiator based on the amount of the radiation-cure resin.

Radiation-cure removal type pressure-sensitive adhesive sheet

A doublefaced pressure-sensitive adhesive sheet including an inner pressure-sensitive adhesive layer is provided. The adhesive layer includes an outer silicone-series release liner and an outer non-silicon-series release liner on the opposite side of the sheet from the silicone-series release liner. The non-silicone-series release liner includes a plastic film having at least three layers, wherein the plastic film including a releasing layer which is a surface layer including a polyethylene film, a surface film layer which is the other surface layer and is equal in coefficient of linear thermal expansion to the releasing layer, and a reinforcing layer having a melting point of 120&deg; C. or higher as an interlayer.

Double-faced pressure-sensitive adhesive sheet and pressure-sensitive adhesive member

A reflection type liquid-crystal in which a light guide plate is in tight contact with a liquid-crystal display element having a reflecting layer through a bonding layer with refractive index in a range of from 1.40 to 1.55 and whole light transmittivity in a range of not less than 90%, the light guide plate being designed so that incident light from an incidence side surface is emitted from a lower surface through prismatic irregularities formed on an upper surface, and the light emitted from the lower surface takes maximum intensity at an angle of 30 degrees or less with respect to a normal to a plane of the lower surface, while maximum intensity of leakage light from the upper surface at that angle is not larger than &frac15; of the maximum intensity in the lower surface, and incident light from the lower surface is transmitted from the upper surface.

Reflection type liquid-crystal display unit

Provided is a release liner formed of a plastic film having a laminated structure of at least three layers, described specifically, as two surface layers, (A) a release functioning layer composed of a polyethylene film having a density of 0.88 to 0.92 g/cm and a melt index not greater than 10 g/10 minutes and (B) a surface film layer having a thermal linear expansion coefficient similar to that of said release functioning layer and, as an intermediate layer, (C) a reinforcement layer having a melting point not less than 120&deg; C. By forming a pressure-sensitive adhesive layer on the surface of the release functioning layer (A) of the above-described release liner, a pressure-sensitive adhesive sheet can be obtained. The release liner exhibits good release function without using a silicone-base releasing agent and has heat resistance sufficient for not causing deformation such as curl even when heat is applied to the liner.

Release liner and pressure-sensitive adhesive sheet

A pressure-sensitive adhesive sheet prepared by coating a composition containing a) 100 parts by weight of monomers composed of from 70 to 100% by weight of a (meth)acrylic acid alkyl ester, said alkyl group having from 2 to 14 carbon atoms, and from 0 to 30% by weight of a monoethylenically unsaturated monomer copolymerizing therewith, b) from 0.1 to 5 parts by weight of a radical chain inhibitor, c) from 0.02 to 5 parts by weight of a polyfunctional (meth)acrylate as a crosslinking agent, d) from 0.005 to 1 part by weight of a photopolymerization initiator, and e) from 0.01 to 10 parts by weight of a silane coupling agent, on a releasing-treated film having a good surface smoothness and photopolymerizing the coated layer to form a pressure-sensitive adhesive layer having a haze value of 1% or lower and a total light transmission of at least 90%. The pressure-sensitive adhesive sheet is excellent in the transparency, the foaming resistance, the low out-gas property, and the discoloring resistance (heat resistance and weather resistance).

Pressure-sensitive adhesive sheets comprising photo-polymerization product and production method thereof

A peelable heat-conductive and pressure-sensitive adhesive is disclosed, which comprises: (a) 100 parts by weight of a polymer produced from a monomer mixture comprising from 70 to 100% by weight of one or more alkyl (meth)acrylates in which the alkyl groups on the average have 2 to 14 carbon atoms and from 0 to 30% by weight of one or more monoethylenic monomers copolymerizable therewith, each based on the amount of the monomer mixture; (b) from 20 to 400 parts by weight of a plasticizer having a boiling point of 150&deg; C. or higher; and (c) from 10 to 1,000 parts by weight of a heat-conductive filler. Also disclosed is an adhesive sheet comprising a substrate and, formed on one or each side thereof, a layer of the adhesive. The pressure-sensitive adhesive can exhibit tight adhesion during use and easy peeling after use.

Peelable heat-conductive and pressure-sensitive adhesive and adhesive sheet containing the same

Pressure-sensitive adhesive of (meth)acrylate, unsaturated acid,

An epoxy resin powder coating composition is described, comprising an epoxy resin and at least a hardener and a filler compounded thereto, wherein the filler is a mixture of from 30 to 180 parts by weight of a needle-like glass powder having an average length of at least 40 .mu.m and an aspect ratio of at least 4:1 and at least 30 parts by weight of a granular inorganic filler having an average particle diameter of 1.0 .mu.m or less, both being based on 100 parts by weight of the epoxy resin. This powder coating composition can provide a coating exhibiting excellent impact resistance not only at room temperature but also at lower temperatures, and further having good flexibility. A steel member with the coating of the present powder coating composition has a high practical value.

Growing community of inventors

Osaka, Japan

Hitoshi Takahira