Tdk Corporation

Tdk Electronics Company, Limited

Toyo Ink Mfg. Co., Ltd.

Other

Kazushi Tanaka

Naoki Hayashida

Hidetake Itoh

Kenji Yoneyama

Yuichi Kubota

Masaharu Nishimatsu

Osamu Shinoura

Yukihiro Isobe

Mamoru Usami

Yukio Kaneko

Rie Ihara

Makio Sugai

Ryozo Konno

Jiro Yoshinari

Akihiko Hosaka

Hiroshi Take

Koichi Ueda

Kunihiko Ozaki

Akira Ohtsuki

Kazuhiro Kuroda

Naoyuki Echigo

Hiroshi Tominaga

Akihiko Kizaki

Hiroyuki Hashiguchi

Tatsuya Kato

Takashi Kikukawa

Koji Mishima

Hiroyuki Yamada

Hideki Sasaki

Tsuyoshi Komaki

Hitoshi Azegami

Daisuke Yoshitoku

Toshifumi Tanaka

Shohei Fujii

Kenichi Kitamura

Takeshi Umega

Akinori Nishizawa

Toshifumi Midorikawa

Nobumori Kanno

Takashi Mihoya

Yasushi Ishikawa

Kentaro Iida

Shuji Sakaguchi

Takashi Nishio

Akira Yamamoto

The present invention provides a hologram recording material and a hologram recording medium that can stably maintain the shape of a recording layer and achieve high diffraction efficiency. A hologram recording material comprising a photoradical polymerizable compound (A), a photopolymerization initiator (B), and a dispersion medium (C). The medium (C) is selected from the group consisting of: a compound of the formula (I): wherein Ris a divalent Chydrocarbon group, Rand Reach independently represent a Chydrocarbon group, k, l, m and n are each independently a number of 0 or more and 5 or less; and a compound of the formula (II): wherein Rrepresents a divalent Chydrocarbon group, Rand Reach independently represent a Chydrocarbon group, and at least one of Rand Rrepresents a Chydrocarbon group.

Hologram recording material and hologram recording medium

An optimal recording exposure is determined by varying in the first to nth stages the recording exposure with a write laser beam to record a bright pattern image and a dark pattern image in each stage as the first to nth bright pattern images and the first to nth dark pattern images, respectively; irradiating the respective pattern images with a read beam to detect the intensity of a diffracted beam from the central portion of each image of the bright and dark patterns; calculating Sa/Sb=SNR, . . . , and Sa/Sb=SNR, where Sato Saare the intensity of a diffracted beam from the first to nth bright pattern images and Sbto Sb, are the intensity of s diffracted beam from the first to nth dark pattern images; and determining a recording exposure which is given at the SNRbeing the maximum value of the resulting SNRto SNR.

Method for determining recording exposure for holographic recording medium and method for recording thereon

An optical reading system is provided to improve read signal quality with increasing its linear recording density. An optical recording medium in which the distance from a light incident surface to an information recording layer is less than 100 &#x3bc;m is irradiated with a laser beam through an objective lens and information stored in the information recording layer is read by means of a PRML detection method. At this time, the constraint length n in the PRML detection method is set to an integer which satisfies 0.5&#xd7;(&#x3bb;/NA)/(LV/f)&#x2212;1&#x3c;n&#x3c;0.5&#xd7;(&#x3bb;/NA)/(LV/f)+1, wherein &#x3bb; represents the wavelength of the laser beam, NA represents the numerical aperture of the objective lens, LV represents the linear velocity of the optical recording medium when recording, and f represents a channel bit frequency when recording.

Optical reading method and optical reading system

The present invention provides a composition for hard coat capable of forming a hard coat layer having the improved anti-staining property, anti-staining durability, scratch resistance, abrasion resistance, antistatic property and the like. A composition for hard coat comprising: an active energy ray-curable silicone-acrylic copolymer (A); an active energy ray-curable polyfunctional compound (B); and an electrically conductive material (C), wherein the active energy ray-curable silicone-acrylic copolymer (A) contains: a polysiloxane block (a-1), an acrylic block (a-2) containing an active energy ray-curable double bond group, and a fluoroalkyl group-containing acrylic block (a-3).

Composition for hard coat, article having hard coat layer and method for producing the article

An active energy ray-curable resin composition comprises a compound (A) having an active energy ray-curable unsaturated bond in a molecule, an anti-staining property-imparting agent (B) which is a fluorine-containing polyether compound having a perfluoropolyether unit, a urethane bond and an active energy ray-curable unsaturated bond in a molecule, a compound (C) represented by the general formula (I): wherein R1, R2 and R3 may be either the same or different, and are respectively an organic group having at least one functional group selected from the group consisting of a vinyl group, an epoxy group, a (meth)acryloxy group, an amino group and a mercapto group, and n is an integer of 0 or more; and inorganic fine particles (D).

Active energy ray-curable resin composition and laminate thereof

The present invention provides a multi-layered object having a hard coat layer capable of improving anti-staining property, anti-staining durability, scratch resistance, abrasion resistance and the like. A multi-layered object comprising a hard coat layer and a light transmitting layer, wherein the hard coat layer is formed from a composition for hard coat comprising: an active energy ray-curable silicone-acrylic copolymer (A); and an active energy ray-curable polyfunctional compound (B), and wherein the active energy ray-curable silicone-acrylic copolymer (A) contains: a polysiloxane block (a-1), an acrylic block (a-2) containing an active energy ray-curable double bond group and a fluoroalkyl group-containing acrylic block (a-3).

Multi-layered object comprising hard coat layer and light transmitting layer, and method for producing the same

The present invention provides a method for producing an optical recording medium having: a supporting substrate; a light transmission layer, which transmits a laser beam; and an information layer formed between the supporting substrate and the light transmission layer, which includes: applying a resin composition on the information layer by a spin coating method to form a coating film, wherein the resin composition contains, as main components: (A) a radical-curing urethane(meth)acrylate, which is obtained by reacting (a-1) a compound having three or more isocyanate groups binding to an aliphatic carbon atom per one molecule thereof and (a-2) a polycaprolacton-modified hydroxyethyl(meth)acrylate; and (B) a radical-curing monomer having a viscosity of 400 mPa.s or less at 25&#xb0; C., curing the coating film by irradiating the coating film with an ultraviolet light or an electron beam to form the light transmission layer.

Methods for producing optical recording medium and optical recording medium

A hardcoat agent composition comprising a fluorine-containing polyether compound (A) having a perfluoropolyether unit, urethane bond and active energy ray reactive group and a curable compound (B) having equal to or more than 2 active energy ray polymerizing groups in the molecule. An optical information medium having a film substance composed of single or multiple layers containing at least the recording layeror the reflecting layer on the supporting substrate, the optical information medium wherein at least either the surface of the supporting substrateor that of the above-mentioned film substance is formed by the hardcoat layercontaining a curable substance of the above-mentioned hardcoat agent composition.

Hardcoat agent composition and optical information medium thereof

An optical recording medium with a high productivity is provided which can certainly record/reproduce data even when a blue or blue-violet laser beam is used as an irradiation light. An optical recording medium has a substrate and a recording layer. The recording layer includes a recording portion and a coating portion. The recording portion and the coating portion are all made substantially from Bi and O. The ratio of the number of O atoms to the total number of Bi atoms and O atoms of the coating portion is less than that of the recording portion. The ratio of the number of O atoms of the recording portion is in the range of from 62% to 77%. The ratio of the number of O atoms to the total number of Bi atoms and O atoms of the coating portion is in the range of from 60% to 70%.

Optical recording medium

An optical information medium includes a light-transmitting supporting substrate, an information recording layer on one surface of the supporting substrate, a protective layer on the information recording layer, and a light-transmitting hard coat layer on an other surface of the supporting substrate. The medium is configured to have a recording/reproducing beam incident into the information recording layer through the hard coat later and the supporting substrate.

Method for evaluating optical information medium and optical information medium

A low-cost artificial fingerprint liquid for quantitatively and with a good reproducibility evaluating an anti-staining property, and a fingerprint adhering property or a fingerprint removing property on the surface of an optical disk such as a reproduction-only optical disk, optical recording disk, magneto-optical recording disk, various displays such as a CRT, and various substances such as glass including a fine-particle-form substance and a dispersion medium capable of dispersing the fine-particle-form substance.

Artificial finger print liquid, testing method for optical information medium using it, and optical information medium

A testing method capable of quantifying abrasion resistance on the translucent base surface of a high-recording-density optical information medium simply and in a form of reflecting an actual application environment, and judging criteria appropriate for the testing method. When an evaluation test in terms of abrasion resistance on a laser beam incident-side surface is conducted on an optical information medium to and/or from which recording and/or reproducing is made by a laser beam shone into an information recording layer from a translucent base side, and which has the focused radius R, of a recording/reproducing laser beam on the translucent base surface, of 40-400 &#x3bc;m, defined by the following expression (1) R=2T tan [sin(NA/n)](1) (in the expression, T is the thickness (&#x3bc;m) of the translucent base, NA numerical aperture of an object lens in the recording/reproducing device, and n refractive index of the translucent base), the abrasion resistance on a laser beam incident-side surface is evaluated based on the error amount of a reproduction signal after a laser beam incident-side surface is abraded by an abrasion wheel specified in ISO9352.

Method of testing optical information medium

The present invention provides inexpensively an article with a hard coat excellent in anti-staining property, lubricity, scratch resistance and abrasion resistance. The present invention provides a method for forming the hard coat. A hard coat agent composition comprising an active energy ray-curable compound is applied onto a surface of an articleto be hard-coat-treated, thereby forming a hard coat agent composition layer, a surface material layer is formed by film-forming with a surface layer material comprising an active energy ray-curable compound having anti-staining property and/or lubricating property on the surface of the hard coat agent composition layer, and active energy rays are irradiated onto the formed hard coat agent composition layer and surface material layer so as to cure the two layers simultaneously, thereby forming a hard coat layercontacting the surface of the articleand an anti-staining surface layercontacting the surface of the hard coat layer

Article having composite hard coat layer and method for forming composite hard coat layer

The present invention provides inexpensively an article with a hard coat excellent in anti-staining property, lubricity, scratch resistance and abrasion resistance. The present invention also provides a method for forming the hard coat. A hard coat agent composition comprising an active energy ray-curable compound is applied onto a surface of an article () to be hard-coat-treated, thereby forming a hard coat agent composition layer, a surface material layer is formed by film-forming with a surface material comprising a fluorine-containing polyfunctional (meth)acrylate compound on the surface of the hard coat agent composition layer, and active energy rays are irradiated onto the formed hard coat agent composition layer and surface material layer so as to cure the both layers simultaneously, thereby forming a hard coat layer () contacting the surface of the article () and an anti-staining surface layer () contacting the surface of the hard coat layer ().

Object with composite hard coating layer and method of forming composite hard coating layer

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Tokyo, Japan

Kazushi Tanaka