36results about How to "Low yellowness index" patented technology

A white film whose thickness is in the range from 1 to 500 μm and which comprises, as principal constituent, a crystallizable thermoplastic, wherein the film comprises at least one UV stabilizer as light stabilizer and at least one white pigment, the use of the film, and also a process for its production.

The present invention relates to an alkyl (meth)acrylate-based thermoplastic resin composition, and to a thermoplastic resin having adjusted scratch resistance and yellowness. More particularly, the total content of vinyl cyanide-based monomers contained within the resin composition is lowered to a level which could not be achieved in conventional technologies and the content of alkyl(meth)acrylate-based monomers is increased while maintaining transparency, flowability, and impact strength and improving scratch resistance and lowering yellowness. More particularly, the alkyl (meth)acrylate-based thermoplastic resin composition and thermoplastic resin according to the present invention have superior impact resistance and transparency and low yellowness. More particularly, the alkyl (meth)acrylate-based thermoplastic resin composition and the thermoplastic resin according to the present invention have high surface hardness and high transparency similar to glass, and therefore are suitable for use in a transparent housing of an electric or electronic product.

Embodiments relate to a polymerizable composition for a polythiourethane-based optical material, the polymerizable composition enabling a high-quality polythiourethane-based optical material to be produced without complicated purification processes, by comprising a certain additive and appropriately adjusting the reactivity of isocyanate such that the viscosity can be maintained to be low for a certain period of time. In addition, the polythiourethane-based optical material of the embodiments has not only a uniform refractive index but also a low yellow index, and thus can be usefully used forvarious plastic optical lenses such as lenses for eyeglasses, camera lenses, etc.

The present invention relates to a polyamide-imide (PAI) polymer comprising repeating units according to any one of formulae (I) and (II) wherein: Z is an alicyclic moiety selected from the group consisting of: a substituted or unsubstituted monocyclic or polycyclic group having 5 to 50 carbon atoms, preferably 6 to 18 carbon atoms; r is a divalent alicyclic moiety selected from the group consisting of: a substituted or unsubstituted monocyclic or polycyclic group having 5 to 50 carbon atoms, preferably 6 to 20 carbon atoms; m and n independently of each other are integers from 0 to 10.

The invention discloses a white polyimide composite film and a preparation method thereof. The composite film comprises a three-layer structure, wherein the surface layer is a white polyimide layer, and the core layer is a polyimide layer; the preparation method is: ( 1) Preparation of white polyimide glue solution: first make TiO 2 Disperse in a solvent, then add polyimide, and mix evenly; (2) Preparation of the precursor glue of the core layer polyimide: dissolve the diamine monomer in the solvent, add the dianhydride monomer after completely dissolving, Stir the reaction to obtain the precursor glue of polyimide; (3) coating of glue: coat the precursor glue of white polyimide, core layer polyimide and white polyimide on the substrate successively. imide glue solution to obtain a multi-layer composite coating; (4) preparation of the film: the multi-layer composite coating is placed in an oven, the temperature is raised, and then naturally cooled to obtain a white polyimide composite film. The invention provides a white polyimide composite film with better mechanical properties and lower yellowness value.

The invention relates to a 1,3-5-tricyclic sulfur propyl mercaptomethyl benzene compound and a preparing method thereof. The preparing method comprises the steps that tri-epoxy propyl mercaptomethyl benzene reacts with rhodanide, an ethanol, dichloromethane and water mixed solvent serves as a reaction solvent, trichloromethane is used for extraction, attapulgite is used for adsorbing impurities, and high-purity colorless 1,3-5-tricyclic sulfur propyl mercaptomethyl benzene is obtained. The 1,3-5-tricyclic sulfur propyl mercaptomethyl benzene compound prepared with the method is high in purity and refractive index and also has the advantages of being high in transmittance and the like, wherein the light transmittance is higher than or equal to 89%, the refractive index is higher than or equal to 1.65, and the yellow index is smaller than or equal to 1.

Glass filler-reinforced solid resins and methods of making the same. The method includes contacting a flowable resin composition and a tool. The flowable resin composition includes a flowable resin and glass filler. The method includes molding or forming the flowable resin composition with the tool. The method includes curing the flowable resin composition, to form the glass filler-reinforced solid resin. Substantially all the surface of the tool that contacts the flowable resin composition during the curing thereof has a surface roughness Ra of about 2 microns or less. A refractive index of the glass filler is within about 0.100 of a refractive index of a cured product of the flowable resin in the glass filler-reinforced solid resin.

A polyvinyl alcohol has a number-average molecular weight (Mn) from 4,400 to 440,000, a molecular weight distribution (Mw / Mn) from 1.05 to 1.70, a degree of saponification from 80 to 99.99 mol %, wherein the polyvinyl alcohol contains an end group represented by a formula (I) below, and a molar ratio (X) of the end group based on total monomer units and the number-average molecular weight (Mn) satisfy a formula (1) below. Such a polyvinyl alcohol has a narrow molecular weight distribution and a high number-average molecular weight with hue good.(In the formula, R1 denotes an optionally substituted aromatic group having a carbon number from 6 to 20, and R2 denotes a hydrogen atom, an alkyl group having a carbon number from 1 to 20, or an optionally substituted aromatic group having a carbon number from 6 to 20.)X·Mn / 44≥0.5  (1)