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

A white coated polyester film is provided which has excellent adhesion to the ethylene-vinyl acetate (EVA) typically used as an encapsulation material in solar modules. The good adhesion properties are achieved with a polymeric coating which includes at least one polyurethane and a crosslinker.

The invention discloses a high-transmittance flexible polyimide substrate ITO conductive film, a preparation method thereof and applications. According to the conductive film, the radio frequency magnetron sputtering technology is used, the flexible PI substrate with both high transparent and high heat-resisting features serves as the substrate, and an ITO conductive layer is deposited by adopting a high-temperature two-step layer to prepare the conductive film. The conductive film has features of low resistance and high transparency, the resistance is lower than 6.4*4<-4> omega.cm, the average transmittance of a visible light region is higher than 80%, and a yellowness index is smaller than 9, and has important application values in manufacturing of a flexible solar cell, a flexible display, an E-book, an electronic label, a photosensor and other photoelectric devices.

The invention discloses a polypropylene composite material capable of resisting gamma ray irradiation and a preparation method of the polypropylene composite material. The polypropylene composite material comprises polypropylene resin and an irradiation stabilizer, wherein the irradiation stabilizer comprises poly{[6-[(1,1,3,3-tetramethylbutyl) amino]]-1,3,5-triazine-2,4-[(2,2,6,6-tetramethyl-piperidyl) imino]-1,6-hexamethylenediamine[(2,2,6,6-tetramethyl-4-piperidyl) imino]}, tri[2,4-di-tert-butyl phenyl] phosphite ester and vinylnaphthalene. By the optimization of the formula of the irradiation stabilizer, the irradiation resistance of polypropylene is improved; the prepared polypropylene material is high in after-irradiation transparency; the mechanical property of the polypropylene material is basically not reduced; meanwhile, the yellowness index is smaller than 3.

The present invention relates to a polythiol compound for a high quality optical material that exhibits excellent physical properties in terms of color, a composition for an optical material including the polythiol compound, a method for producing an optical material, and a method for preparing the polythiol compound. The method includes reacting an epichlorohydrin compound containing 0.5% by weight or less of impurities with 2-mercaptoethanol. The polythiol compound is prevented from being colored. The polythiol compound can be used to produce a urethane optical material that is prevented from being colored and has a low yellowness index and a good color. The polythiol compound can be used to produce various optical materials including urethane optical materials. The optical material can be used to manufacture an optical lens having a good color. The optical lens can be used as a spectacle lens, a polarizing lens, a camera lens, or the like.

The invention discloses a gamma-ray-resistant anti-aging transparent polypropylene composite material and a preparation method thereof, the polypropylene composite material comprises polypropylene resin, a nucleating agent, an acid acceptor and an irradiation stabilizer, and the irradiation stabilizer comprises methyl phenyl vinyl silicone rubber, a coupling agent, a montmorillonite material, an antioxidant and a light stabilizer. By optimizing the formula of the irradiation stabilizer, the irradiation resistance of the polypropylene is improved, and the prepared polypropylene material has good transparency and excellent aging resistance after irradiation, can be used at high temperature for a long time without discoloration, and has good mechanical properties.

The invention provides a fluorine-containing aromatic diamine compound, a preparation method thereof and a colorless transparent polyimide film. The fluorine-containing aromatic diamine compound has a structure as shown in a formula V or a formula V ', a PI film prepared by polymerizing the compound with commercial diamine and dianhydride monomers has relatively high light transmittance and relatively low yellowness index; meanwhile, the heat stability is excellent, the glass transition temperature is high, and the mechanical property is good; the film can be widely applied to the fields of flexible displays, wearable devices, 5G equipment, thin film solar cells and the like. The glass transition temperature of the PI film is 353-407 DEG C, and the 5wt% thermal weight loss temperature exceeds 480 DEG C; the tensile strength is 121-133 MPa, and the tensile modulus exceeds 2.5 GPa; under high frequency, the dielectric constant is 2.69-3.01, and the dielectric loss is 0.003-0.012; the cut-off wavelength is less than or equal to 351 nm, the optical transmittance at 450 nm is 86-92%, and the yellowness index is far less than 2.5.

The invention discloses a high-acrylonitrile-content ABS composition which is composed of a rubber dispersed phase existing in a particle form and a continuous phase of a random copolymer formed by copolymerization of styrene and acrylonitrile. The composition also comprises a maleic anhydride or methacrylate copolymer. The acrylonitrile content in the composition is 24.0-28.0%. The product ABS composition prepared with the method provided by the invention has high acrylonitrile content, white color, and low residual monomer content. The ABS composition can be well applied in the fields such as sheet material manufacturing.

The invention provides modified polyvinyl chloride and a preparation method thereof, an irradiation-resistant sterilization venous indwelling needle connecting hose and an indwelling needle. Polyvinylchloride is used as a matrix; amorphous calcium silicate is used as an acid absorbent; triazinyl hindered amine is adopted and matched with calcium soap, zinc soap, phosphite ester, a plasticizer, epoxy vegetable oil and an auxiliary stabilizer according to a certain proportion, under the combined action of the components, the irradiation resistance of the venous indwelling needle can be improved, and the problems that after irradiation sterilization, the pH change of a product is large, and color yellowing is large are solved. And meanwhile, the venous indwelling needle can be ensured not tobe dissolved out by aluminum.

The invention discloses a white polyimide composite film and a preparation method thereof. The composite film comprises a three-layer structure, wherein a surface layer is a white polyimide layer, anda core layer is a polyimide layer. The preparation method comprises the following steps: (1) preparation of a white polyimide glue solution: dispersing TiO2 in a solvent, adding polyimide, and carrying out uniform mixing; (2) preparation of a precursor glue solution of core-layer polyimide: dissolving a diamine monomer in a solvent, adding a dianhydride monomer after complete dissolution, and carrying out a stirring reaction to obtain the precursor glue solution of polyimide; (3) coating of the glue solution: sequentially coating a substrate with the white polyimide glue solution, the precursor glue solution of the core-layer polyimide and the white polyimide glue solution so as to obtain a multi-layer composite coating; and (4) preparation of the film: putting the multi-layer composite coating in an oven, carrying out heating, and then naturally cooling the coating to obtain the white polyimide composite film. The white polyimide composite film provided by the invention is excellentin mechanical properties and low in yellowness value.

The invention discloses intermediate film for laminated glass. The intermediate film is characterized by being prepared from, by weight, 0.2-0.4 part of antioxidant, 10-18 parts of sodium acrylate, 3-5 parts of polyethylene and 80-90 parts of ethylene. The invention further discloses the laminated glass containing the intermediate film. Compared with the prior art, when applied to the laminated glass, the intermediate film for the laminated glass has the advantages of high glass strength, less deformation under stress, excellent transparency, a perfect real effect and good bonding performance.

The present invention provides a polyimide comprising a structural unit, which comprises a first structural unit represented by formula (1) and a second structural unit represented by formula (2), wherein A, D and E are defined herein. A polyimide film formed by the polyimide has a low linear thermal expansion coefficient.

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)

There is provided a process for producing an ionomer comprising the steps of (a) admixing in a mixer a halogenated copolymer with at least one nitrogen and/or phosphorus based nucleophile and (b) extruding the mixture from step (a). The process takes place with high conversion and the resulting ionomer contains a low amount of residual nucleophile and has a low yellowness index.