Abstract: There is provided a WORM type organic optical recording media comprising a recording layer, a reflective layer and a protective layer which are formed in sequence on a substrate, the recording layer consisting of near infrared absorbing dye able to absorb a laser beam and to generate heat and of a thermosetting or photocuring resin. The organic optical recording medium can be prevented from being rewritten by heating up to 50.degree. C. or irradiating with a UV light, said dye being capable of absorbing near infrared rays and generating heat.The medium exhibits stable reading characteristics of at least 45 dB even after irradiating with a light with a short wavelength. In addition, it also has a function of record locking by curing the resin of the recording layer, so that, once recorded, rewrite or additional recording is not allowed therein.

Abstract: There is provided a process for the preparation of composite semi-permeable membrane superior in selectivity and permeability, capable of improving bonding strength between a porous support layer and a reinforcement and mechanical strength of semi-permeable membrane.The composite semi-permeable membrane is prepared by subjecting woven fabric or non-woven fabric to corona discharge with a discharge power of approximately 10 to approximately 15 watt for a period of approximately 20 to approximately 40 seconds, spraying water over one surface of the fabric, casting porous support substance on the other surface of the fabric when a time of approximately 5 to approximately 10 seconds has elapsed after the spray, and laminating a crosslinked polyamide ultrathin film on the porous support substance, the polyamide ultrathin film being synthesized by interfacial polycondensation of a multifunctional amine solution and a multifunctional halogen solution.

Abstract: An optical recording medium using a charge transfer complex is disclosed. A charge transfer complex (cyanine-TCNQ) is formed from cyanine-based dyes having the following formula (I). ##STR1## (Wherein, R represents heteroaromatic residue,R' represents alkyl group, andn represents a positive integer not less than 2)with TCNQ or derivatives thereof to apply the complex as a recordable material in a semiconductor laser. To record information, a laser beam is focused to the optical recording medium, the cyanine-TCNQ in the recording layer absorbs the laser beam and is melted or decomposed. Reproducing can be accomplished by reading the reflectivity difference between the recording portion and the non-recording portion with lower power than the recording laser.

Abstract: There is disclosed an organic optical recording medium with high data storage density, high data rates and long data archival capabilities, useful as a medium for recording a variety of information or pictures.In a preferred embodiment, the optical recording medium according to the present invention comprises a substrate, a reflective layer, a charge-generating layer containing at least one charge-generating material, a charge-transferring layer containing at least one charge-transferring material, a recording layer containing at least one electric field-discoloring element, a plurality of spacers, an air layer and a protective layer.A laser beam is absorbed to the charge-generating material contained in the charge-generating layer, to generate charges, which are subsequently transferred to the surface of the recording layer by the charge-transferring layer.With the influence of the charge generated, the illuminated area having the charges puts on a color different from that in the other areas.

Abstract: An organic-optic recording tape of higher capacity and higher packing density of data. This tape comprises a backcoating layer, a base film coated on the backcoating layer, and a complex functional layer for writing, reading and erasing data. The complex functional layer is coated on the base film and selectively focused by laser beams of different powers outputted from a laser diode in order to write, read or erase data. This complex functional layer is made of a block polymer prepared by blending a thermoplastic elastomer and a viscoelastic transparent thermoplastic high-molecular resin or polymerizing them. Near infrared absorbing organic colorants are dispersed in the complex functional layer. The transparent thermoplastic resin has a glass transition temperature higher than that of the elastomer. The recording is effected by employing a laser beam of lower power capable of inducing thermal expansion of the elastomer and formation of a bump.

Abstract: There is disclosed an organic optical recording medium with high data storage density, high data rates and long data archival capabilities, useful as a medium for recording a variety of information or pictures.In a preferred embodiment, the optical recording medium according to the present invention comprises a substrate, a reflective layer, a charge-generating layer containing at least one charge-generating material, a charge-transferring layer containing at least one charge-transferring material, a recording layer containing at least one electric field-discoloring element, a plurality of spacers, an air layer and a protective layer.A laser beam is absorbed to the charge-generating material contained in the charge-generating layer, to generate charges, which are subsequently transferred to the surface of the recording layer by the charge-transferring layer.With the influence of the charge generated, the illuminated area having the charges puts on a color different from that in the other areas.

Abstract: There is provided a WORM type organic optical recording medium comprising a recording layer, a reflective layer and a protective layer which are formed in sequence on a substrate, the recording layer consisting of near infrared absorbing dye able to absorb a laser beam and to generate heat and provided with a curing layer of thermosetting or photocuring resin thereon or thereunder. There is also provided a method for the prevention of rewrite in the organic optical recording medium, comprising subjecting the organic optical recording medium to heating up to 50.degree. C. or exposure to a UV light, to cure the curing layer. The organic optical recording medium requires reduced amounts of the dye and, thus, has improved reflectivity. By virtue of this improvement in reflectivity, a low-price metal may be employed in the reflective layer, bringing about additional economic benefit, along with lower requirements for dye.

Abstract: There is disclosed a biodegradable copolyester having a combination structure consisting of one or more repeating unit of alkyleneterephthalate and one or more repeating unit of hydroxyalkanoate, represented by the following general formula I: ##STR1## wherein n is an integer not more than 10, R is --CH.sub.3 or --C.sub.2 H.sub.5,X is, ##STR2## and a, b and c are independently a natural number, along with a preparation method therefor.An aromatic polyester have repeating unit of alkyleneterephthalate is reacted with an aliphatic polyester having repeating unit of hydroxyalkanoate at 100.degree. C. or more in a proper solvent, such as nitrobenzene and dimethylsulfoxide, in the presence of a catalyst, such as dibutyltin oxide, tin[IV] chloride, tin[IV] octoate, hexabutyl distannoxane, tributyltin methoxide, or tributyltin chloride. It is superior in biodegradability and can be produced in low cost.

Abstract: A method for the production of polyester film is disclosed including the steps of: esterifying at least one species of carboxylic acid with at least one species of glycol; adding to the ester composition macro particles of silica of an average diameter of approximately 1.3 to approximately 2.0 .mu.m and fine particles of aluminum oxide of an average diameter of approximately 20 to approximately 200 nm; polycondensing the resulting mixture, to give a filled polyester resin; melting the filled polyester resin; molding the melt into a sheet; and biaxially stretching the sheet to produce a film product which is superior in haze and in static friction coefficient (U.sub.x)/kinetic friction coefficient (U.sub.k) ratio The polyester film of the present invention does not appear milky. In addition, after slitting the polyester film and tightly winding it around a roll it does not have a substantial number of protrusions.

Abstract: There is disclosed a method for the production of aliphatic copolyester film.The method comprises the steps of: applying esterification or ester-interchange to a reaction mixture of at least one acid component selected from the group consisting of succinic acid, succinic anhydride and succinic acid ester, 1,4-butanediol as a main diol component, 2,2-dimethyl-1,3-propanediol of 1 to 30% by mole based on the mole of the acid component, multifunctional compound 0.01 to 1% by mole, based on the mole of the acid component, multifunctional compound have more than three functional group of hydroxy group or carboxy group at below 220.degree. C., so as to give an oligomer mixture; polycondensing the oligomer into an aliphatic copolyester at a temperature of 240.degree. to 260.degree. C. under reduced pressures of not more than 1 mmHg in the presence of a catalyst; and melt-extruding the aliphatic copolyester using T die.

Abstract: A method for the production of biaxially stretched polyester film.The method comprises the steps of: adding cubic calcium carbonate particles of calcite structure satisfying the following conditions at any stage of polyester preparation, so as to prepare polyester resin:d.sub.25 /d.sub.75 <2.00 (1)0.7.ltoreq.d.sub.50 .ltoreq.1.50 (2)a:b:c=1:(1.about.1.5):(1.about.1.5) (3)wherein d.sub.25, d.sub.50 and d.sub.75 are the diameters (.mu.m) of particles when the accumulated weights of the particles are on the order of 25, 50 and 75% of the total weight of the particles, respectively, and a, b, c are width, length and height of the cubic calcium carbonate particles and the shortest one among a, b and c is set a=1; and applying melt-extrusion to the polyester resin.The biaxially stretched copolyester film provided is superior in travelling capacity as well as abrasion resistance and scratch resistance, so that it is useful for magnetic recording media.

Abstract: A method for preparation of a polyether-ester elastomer. The method comprises admixturing dibasic acid with short chain diol for the formation of a short chain ester monomer represented :into general formula (I) and with polyglycol for the formation of a long chain ether moromet represented into general formula (II), adding the alkali salt of dialkylsufoisophthalate to the admixture to react the admixture until the discharge of methanol is tip to above 70%, adding stabilizing agent to perform the polymerization reaction, and then, blending phenolic alkali metal salt. ##STR1## wherein R is a biradical obtained by removing carboxyl group from a dicarboxylic acid having a molecular weight not more than 400,D is a biradical obtained by removing hydroxyl group from a short chain diol having a molecular weight not more than 250, andG is a biradical obtained by removing hydroxyl group from a long chain ether glycol having a molecular weight of a range of about 400 to 4,000.

Abstract: A biaxially stretched polyester film is disclosed.The biaxially stretched polyester film comprises substantially spherical silica particles of colloidal state having average diameters ranging from approximately 20 nm to approximately 200 nm in amounts ranging from approximately 0.005% to approximately 1.0% by weight based on the total weight of the polyester; and alumina particles having average diameters ranging from approximately 50 nm to approximately 500 nm in amounts ranging from approximately 0.05% to approximately 5.0% by weight, the average diameter of the alumina particles being larger than that of the silica particles.The biaxially stretched film prepared according to the present invention has excellent surface properties such as slip property and abrasion resistance, so that the film may be used for manufacturing final products without scratches and white powders occurring thereon.

Abstract: A method for the production of polyester suitable to be molded into a film with excellent surface properties.The method comprises passing dispersion-in-water type silica sol with pH 8 to 11 including sodium oxide as a stabilizer and silica particles with average diameters 0.01 to 0.3 .mu.m through a column of cation exchange resin having the following formula 1 and the strong basic anion exchange having the following formula 2, in sequence to adjust the pH value to 2 to 4, adding an hydrogen bonding agent and ethylene glycol thereto, heating the resultant silica sol under a reduced pressure to remove water, so as to obtain dispersion-in-ethylene glycol type silica sol, and adding 0.01 to 5% by weight of the dispersion-in-ethylene glycol type silica sol, as based on the weight of polyester to be produced, at any step during the ester interchange reaction.

Abstract: A method for preparation of a biaxially stretched polyester film with good slip and release properties comprising coating an acrylic resin-based aqueous resin compound, which is derived from adding an amino-modified silicone compound having the structural formula (1), a waxy additive and inert inorganic particles to an acrylic resin, on at least one surface of a mono-axially stretched polyester film, drying the polyester film coated with the aqueous resin compound, mono-axially stretching the dried polyester film in a direction perpendicular to that of the previous mono-axial stretching and heat-treating the stretched polyester film: ##STR1## wherein R' is a hydroxyl group, a methyl or an ethyl; R" is a hydrogen carbide which has 0 to 10 carbon atoms and to which NH or NH.sub.2 is bonded; m is an integer in the range of 5 to 1,000; n is an integer in the range of 100 to 20,000; and n/(m+n)=0.5.

Abstract: A siloxane modified polyimide resin having high heat resistance and processability is prepared by reacting a siloxane diamine of formula (1) and an aromatic diamine of formula (2) with an aromatic tetracarboxylic dianhydride of formula (3) in a polar solvent. ##STR1## wherein, R represents ##STR2## R.sub.1 and R.sub.2 represent aromatic or aliphatic hydrocarbons; n represents an integer of 1 to 1000;X.sub.1 represents ##STR3## X.sub.

Abstract: The present invention relates to water-soluble copolymerized polyester resin suitable to produce a polyester film having a good adhesion and surface properties.That is, the composition of the present invention comprise 50.about.85 mol % of aromatic dicarbonic acid, 0.5.about.25 mol % of aromatic dicarbonic acid containing sulfonic acid alkali metallic base and 0.5.about.25 mol % of dicarbonic acid containing silane system represented by the following formula (I) in the total dicorbonic acid components, wherein the glycol components contained in the composition comprising more than 60 mol % of aliphatic or alicyclic glycol and 1.about.40 mol % of diethylene glycol or triethylene glycol. ##STR1## wherein R.sub.1 is aliphatic hydrocarbon group of 1 to 15 carbon atoms, R.sub.2 is aliphatic hydrocarbon group of 1 to 4 carbon atoms.