Nitto-Denko Corporation

Hiroshima University

Kazuhisa Maeda

Kunio Nagasaki

Masaaki Arakawa

Katsumi Hori

Shinji Inokuchi

Kenichi Okada

Shuzo Fujiwara

Mitsuyoshi Shirai

Tomonari Naito

Teiji Sakashita

Masayuki Okamoto

Akira Hirao

Kazuhito Okumura

Isao Hirose

Tetsuya Hirose

Michio Umeda

Yusuke Sugino

Tetsuo Kishimoto

Akiko Miyano

Shigenobu Okazawa

Koji Nishiguchi

Michiro Kawanishi

Naoki Kohno

The present invention relates to an acrylic pressure-sensitive adhesive including: a) an acrylic polymer containing, as a monomer unit, an alkyl (meth)acrylate including an alkyl group having 1 to 20 carbon atoms in an amount of 50% by weight or more; and b) a tackifier resin, in which the acrylic polymer a) contains two kinds of monomer units having a difference in solubility parameter (SP value) of 0.2 (MPa)or more, each in an amount of 15% by weight or more.

Acrylic pressure-sensitive adhesive, acrylic pressure-sensitive adhesive layer and acrylic pressure-sensitive adhesive tape or sheet

The present invention relates to a photocurable acrylic viscoelastic material composition including: an acrylic monomer mixture containing an alkyl (meth)acrylate as a main monomer component and a polar group-containing vinyl monomer, or a partial polymerization product thereof; a (meth)acrylate compound having at least one isocyanate group within the molecule thereof; and a photopolymerization initiator. The photocurable acrylic viscoelastic material composition of the present invention has, by virtue of the above-described construction, excellent pot life and excellent storage stability, despite containing an isocyanate compound having at least one isocyanate group within the molecule thereof, and further can form an acrylic viscoelastic material excellent in the holding power at high temperatures through photocuring. Also, the acrylic viscoelastic material and acrylic viscoelastic material layer tape or sheet of the present invention is excellent in the holding power at high temperatures.

Photocurable acrylic viscoelastic material composition, acrylic viscoelastic material, acrylic viscoelastic material layer tape or sheet and proceed for producing the same

There is provided a model that can evaluate properties of viscoelasticity and also rubber elasticity of an elastic material. A correlation equation between stress and strain that is calculated from: a correlation equation between stress, strain, elastic modulus and relaxation time, calculated based on a Maxwell model in which an elastic element and a viscous element are placed in series; and a correlation equation between strain and elastic modulus, including different moduli depending on properties, the correlation equation between stress and strain including different moduli depending on said properties as parameters is output as a stress-strain curve formula. There is one feature in finding a correlation between the strain and the elastic modulus, and this allows a large deformation behavior of an elastic material having properties of both rubber elasticity and viscoelasticity to be expressed with high quantitative characteristics on simulation.

Program for outputting stress-strain equation and its device

The present invention relates to a process for producing a pressure-sensitive adhesive layer, which includes irradiating a photopolymerizable acrylic pressure-sensitive adhesive composition layer provided between two films with an active energy beam to polymerize the photopolymerizable acrylic pressure-sensitive adhesive composition layer, in which the polymerization is performed while a layer of a composition for preventing polymerization inhibition which is curable with an active energy beam in the atmosphere is provided on a side surface of the photopolymerizable acrylic pressure-sensitive adhesive composition layer. According to the process for producing a pressure-sensitive adhesive layer of the present invention, owing to the construction as discussed above, it is possible to reuse a film. Moreover, it is possible to prevent a lowering in the cohesive force in the side surface of the thus formed pressure-sensitive adhesive composition layer caused by a lowering in the polymerization degree in the side surface of the photopolymerizable acrylic pressure-sensitive adhesive composition layer during the photopolymerization.

Process for producing pressure-sensitive adhesive layer

A method and an apparatus for producing an adhesive tape are disclosed in which an adhesive tape is produced while a liquid reservoir is almost hermetically sealed by bringing a blade into contact with an upper laminate roller, and supplement of adhesive to the liquid reservoir is controlled so that the liquid surface of the adhesive reserved in the liquid reservoir comes into contact with the back face of the blade.

Method and apparatus for producing adhesive tape, and adhesive tape

An aqueous dispersion type pressure-sensitive adhesive composition which has a small increase of a peel force to a release liner having a silicone release agent applied thereto or back coating layer, and pressure-sensitive adhesive sheets comprising the composition. The aqueous dispersion type pressure-sensitive adhesive composition comprises an aqueous dispersion of a polymer obtained by copolymerizing a monomer mixture comprising one or more alkyl (meth)acrylates as the main component and at least one silane monomer, and an organic compound capable of bonding to the silane monomer.

Aqueous dispersion type pressure-sensitive adhesive composition, and pressure-sensitive adhesive sheet

A re-peeling pressure-sensitive adhesive or a re-peeling pressure-sensitive adhesive tape satisfying four conditions, besides (3) and (4), (1) and (2) or (1') and (2'): (1) the average releasing force in each releasing rate in the case of releasing at a releasing rate of from 10 to 100 meters/minute is from 50 to 1,000 g/25 mm, (2) the difference between the maximum value and the minimum value of the releasing force of the releasing chart pattern obtained by the release in (1) is not larger than 2/3 of the average releasing force or not larger than 500 g/25 mm, (1') the average releasing force in each releasing rate in the case of releasing at a releasing rate of from 1 meter/minute to 50 meters/minute is from 100 g/25 mm to 1,000 g/25 mm, (2') in the relation between the releasing force and the releasing rate after adhering to an adherend and preserving, the peak of the releasing force does not exist in the range of the releasing rate of not higher than 50 meters/minute, (3) the rolling initial tacking force is from 30 to 800 g/25 mm, and (4) the retentive force is at least 15 minutes under a load of 500 g. The pressure-sensitive adhesive and pressure-sensitive adhesive tape can be repeatedly adhered to or peeled from an adherend such as a paper diaper without breaking the adherend.

Re-peeling pressure-sensitive adhesive tape or pressure-sensitive

A masking tape or sheet comprising a substrate comprising a resin (a) comprising a polypropylene as a hard segment and an olefin copolymer as a soft segment, and an adhesive layer formed on one side of said substrate. The masking tape of the present invention can precisely follow the shape of adhesion surfaces having curves, and can provide fine parting lines. In particular, when polypropylene resin (b) is added to the resin (a), the back face of the masking tape becomes smooth and can be adhered easily with fingers, and the tape can be easily cut with a cutter knife. Hence, the use of the masking tape of the present invention leads to an improved efficiency of adhesion work, particularly when the work is manually done. In addition, since the masking tape of the present invention does not contain vinyl chloride in the substrate, the masking tape after use can be incinerated without generating a toxic gas such as chlorine gas.

Masking tape or sheet

Disclosed are an expandable fixing tape comprising a base material composed of an expandable portion and a substantially non-stretchable portion, and a fixing means provided on at least one non-stretchable portion which is present at one end of the base material, wherein the expandable portion exhibits a load of not more than 5.0 kg/25 mm at 200% expanding and a permanent set of not less than 30% under the condition of 200% expanding, and the substantially non-stretchable portion has a ductility of less than twice under a load of not more than 0.5 kg/25 mm and a base material composed of an expandable portion, which is a thin layer portion having a thin thickness, at the central portion in the lengthwise direction and substantially non-stretchable portions, which are thick layer portions having a thick thickness, at both the end portions, a fixing means provided on at least one non-stretchable portion which is present at one end of the base material, wherein the expandable portion can be expanded to the length of at least three times under a load of 1.5 kg/25 mm and has a permanent set of at least 30% under the condition of 200% expanding, and the thickness of the expandable portion is not more than 90% of the thickness of the non-stretchable portion. These tapes can be easily expanded by a weak force at use and are very practical and easily usable, and are suitably used for packaging bags, boxes, etc. or for treating sanitary articles used.

Growing community of inventors

Ibaraki, Japan

Kazuhisa Maeda