Bayer Aktiengesellschaft

Sony Corporation

Bayer Technology Services Gmbh

Bayer Antwerpen N.v.

Bayer Materialscience Ag

Thomas Bieringer

Horst Berneth

Serguei Kostromine

Rainer Hagen

Friedrich-Karl Bruder

Wilfried Haese

Rafael Oser

Josef-Walter Stawitz

Thomas Sommermann

Peter Landenberger

Karin Hassenr&uuml;ck

Uwe Claussen

Dietrich Haarer

Ralf Ruhmann

Karin Hassenrück

Roland Wuttke

Masanobu Yamamoto

Hans-Werner Schmidt

Hidetoshi Watanabe

Yuichi Sabi

Ralf Neigl

Sakuya Tamada

Thomas Fischer

Takashi Iwamura

Mitsuaki Oyamada

Joachim Stumpe

Ingmar Dorn

Dirk Van Meirvenne

Franky Bruynseels

Claus D Eisenbach

Steffen Kühling

Michael Rutloh

René De Cleyn

Joachim Rubner

Sergei Kostromin

Karl Fischer

Carsten Frenz

Thomas Breiner

Uwe Gessner

Lutz Laser

Rino E Kunz

Axel Müller

Stephan Zilker

Polymeric material suitable for the preparation of optical recording media for volume data storage is disclosed. The molecular structure of the material contains a main chain derived from any of poly(meth)acrylate, poly(meth)acrylamide, polysiloxane, polyurea, polyurethane, polyester, polystyrene and cellulose, and the side chains contain a) azobenzene dye, b) form anisotropic grouping, and c) at least one monomer selected from the group consisting of  where R=H or methyl,R' and R&#x2033; independently denote CnH2n+1 or CnH2n-OH and R&#x2032;&#x2033; denotes &#x2014;CnH2N&#x2014;OH.

Rewriteable optical recording material having good solubility

An optical layer structure having at least two layers and also a sensor based on this layer structure are described. The layer structure comprises at least a substrate layer and at least one (light) waveguide layer and a coupling element for the coupling of the optical beam, the layer adjacent to the waveguide layer having a smaller refractive index than the waveguide layer, and at least one layer consisting of a photoaddressable polymer.

Layer structure and optical waveguide sensor based on photoaddressable polymers

Optical data carrier comprising a preferably transparent substrate which may, if desired, have previously been coated with one or more reflection layers and to whose surface a light-writeable information layer, if desired one or more reflection layers and if desired a protective layer or a further substrate or a covering layer have been applied, which can be written on or read by means of blue, red or infrared light, preferably laser light, where the information layer comprises a light-absorbent compound and, if desired, a binder, characterized in that at least one cyanine dye is used as light-absorbent compound.

Optical data carrier comprising a cyanine dye as light-absorbent compound in the information layer

An optical recording material for binary, multibit or volume data storage is described. The optical recording material comprises: (a) at least one dyestuff selected from polymeric azo dyestuffs and oligomeric azo dyestuffs, the dyestuff changing its spatial arrangement upon irradiation with polarized electromagnetic radiation; and (b) optionally at least one grouping having form anisotropy. The optical recording material has the following characteristics: (i) the absorption maximum of the dyestuff(s) is at least 30 nm less than 400 nm and/or at least 30 nm greater than 400 nm; (ii) at 400 nm the dyestuff reaches an optical density of not more than 60% of its absorption maximum; (iii) the optical recording material has the capacity for being rewritten on by changing the state of polarization of actinic light, an intensity of at least 80% of the original value being achieved after a deletion/rewriting cycle; and (iv) at 400 nm, under identical conditions, an optical writing operation performed upon the optical recording material proceeds no more slowly than at 500 nm, and birefringence values induced during the optical writing operation do not differ from those birefringence values induced at 500 nm by more than 10%.

Erasable optical recording material for blue lasers

Block polymers suitable for the preparation of data storage media are disclosed. The media produced of the inventive of the polymers has thickness in the range of a few millimeters. In contrast with currently available materials that feature high optical density the inventive polymers feature increased dilution of dyes (decrease in optical density) and decrease in the holographic diffraction efficiency.

Block copolymers for optical data storage

An optical recording medium having at least a recording layerand a light transmitting layerformed on a substrate, in which the recording layeris made of an organic material for absorbing an incident light of wavelength of 360 nm to 460 nm, and inducing physical change or chemical change to vary the refractive index, the light transmitting layeris 10 &#x3bc;m to 177 &#x3bc;m in thickness, the relation between absorption coefficient 'k' and pyrolysis temperature Tof organic material is950(&#xb0; C.)&#x3c;(Tdec (&#xb0; C.)&#x2212;20)/k&#x3c;4100&#xb0; C.&#x2003;&#x2003;(1),and the absorption coefficient 'k' is k&#x3e;0.0.

Optical recording medium

A process for the preparation of optical data carriers made of a particualr polycarbonate is disclosed. The polycarbonate is prepared by the phase boundary process that entails reacting at least one dihydroxydiarylalkane in the form of its alkali metal salts with phosgene in the heterogeneous phase in the presence of sodium hydroxide solution and an organic solvent. The process is characterized in that the feedstock have but low content of Fe, Cr, Ni, Zn, Ca, Mg, Al metals or homologues thereof, and in that the organic solvent is separated off, and in that the polycarbonate which is obtained is worked up. The resulting polycarbonate is particularly useful in producing optical data carriers.

Optical data carriers and method for producing the same

Optical data carrier comprising a preferably transparent substrate which may, if desired, have previously been coated with one or more reflection layers and to whose surface a light-writeable information layer, if desired one or more reflection layers and if desired a protective layer or a further substrate or a covering layer have been applied, which can be written on and read by means of infrared light, preferably laser light, particularly preferably light having a wavelength in the range 750-800 nm, in particular 770-790 nm, where the information layer comprises a light-absorbent compound and, if desired, a binder, characterized in that at least one cobalt(III) phthalocyanine in which the Co metal centre bears two axial substituents R and R which represent, independently of one another, CN, SCN, alkoxy or alkylthio is used as light-absorbent compound.

Optical data store comprising an axially substituted cobalt phthalocyanine in the light-writeable information layer

An optical data storage medium containing a preferably transparent substrate which has optionally already been coated with one or more reflecting layers and onto the surface of which a photorecordable information layer, optionally one or more reflecting layers, and optionally a protective layer or an additional substrate or a top layer are applied, which data storage medium can be recorded on and read using blue or red light, preferably laser light, wherein the information layer contains a light-absorbing compound and optionally a binder, characterized in that at least one diaza hemicyanine dye is used as the light-absorbing compound.

Optical data storage medium containing a diaza hemicyanine dye as the light-absorbing compound in the information layer

Optical data stores containing a Co-phthalocyanine complex in the information layer recordable using light

An optical data storage medium containing a preferably transparent substrate which has optionally already been coated with one or more reflecting layers and onto the surface of which a photorecordable information layer, optionally one or more reflecting layers, and optionally a protective layer or an additional substrate or a top layer are applied, which data storage medium can be recorded on and read using blue or red light, preferably laser light, wherein the information layer contains a light-absorbing compound and optionally a binder, characterized in that at least one triazacyanine dye is used as the light-absorbing compound.

Optical data storage medium containing a triazacyanine dye as the light-absorbing compound in the information layer

Process for intensifying information in photo-addressable side-chain

Side-group polymers whose permanently shape-anisotropic side groups carry lateral substituents are particularly suitable, owing to their excellent properties, for optical components which can be employed, in particular, in optical data storage and transfer.

Side-group polymers, and their use for optical components

Growing community of inventors

Odenthal, Germany

Thomas Bieringer