555 results about "Post curing" patented technology

The invention provide a new class of silicone-containing prepolymers containing dangling hydrophilic polymer chains. This class of silicone-containing prepolymer is capable of being actinically crosslinked to form a silicone hydrogel material with a hydrophilic surface without post curing surface treatment. The present invention is also related to silicone hydrogel contact lenses made from this class of silicone-containing prepolymers and to methods for making the silicone hydrogel contact lenses.

The invention discloses a preparation method for a fiber reinforced carbon-silicon carbide-zirconium carbide-based (C/C-SiC-ZrC) composite material. The preparation method comprises the following steps of: (a) evenly dispersing ZrC nanopowder in absolute ethyl alcohol; (b) mixing phenolic resin and ZrC dispersion liquid to form slurry; (c) immersing a two-dimensional carbon fiber sheet into the slurry for dipping and drying, then carrying out continuous superposition paving on the two-dimensional carbon fiber sheet, and carrying out curing and post-curing treatment to prepare a fiber-reinforced sintered body; (d) cracking the fiber-reinforced sintered body to obtain a porous C/C prefabricate; (e) placing silicon powder into a graphite crucible, burying the porous C/C prefabricate into the silicon powder, heating to 1,500-1,650 DEG C, and preserving heat for preset time so as to carry out liquid silicon permeation. The method can be used for improving the high-temperature oxidizing property and ablation property of the carbon fiber reinforced ceramic (C/C-SiC) composite material.

The invention discloses a resin-bonded grinding tool for processing sapphire crystals and a preparation method for the resin-bonded grinding tool. The resin-bonded grinding tool for processing the sapphire crystals is obtained by mixing, hot-pressing, post-curing and post-trimming forming materials and a matrix, wherein the forming materials include diamond abrasives, thermosetting resin powder, filling agents, silicon carbide whiskers and wetting agents. The silicon carbide whiskers with the Mohs hardness of 9.5 grades are added into the resin-bonded grinding tool, so that the grinding tool for grinding the sapphire crystals is high in efficiency and long in service life, and the surface smoothness of the sapphire crystals can be improved by means of the polishing function of the silicon carbide whiskers.

The present invention is directed to polyurethane-urea materials and to a process for their production. These polyurethane-ureas are preferably optically clear and comprise the reaction product of a (cyclo)aliphatic polyisocyanate or prepolymer thereof, with an isocyanate-reactive component that comprises one or more aromatic diamines which contains two primary amine groups, and one or more compounds containing two secondary amine groups which may be linked to aliphatic and/or aromatic moieties. This isocyanate-reactive component may additionally comprise one or more hydroxyl-functional compounds. The present invention offers a relatively fast “Green-Cure Time” of solid polyurethane-ureas which enables these to be demolded in a relatively short time period, followed by subsequent post-curing outside the mold.

The invention relates to a method for manufacturing a bamboo macrofiber composite material. Bunchy bamboo fibers of which the green and yellow are removed are taken as raw materials and dipped with awater soluble phenol formaldehyde adhesive, and the production steps comprise material preparation (comprising the preparation of bamboo macrofiber reinforcement and a water soluble phenol formaldehyde resin matrix), adhesive dipping, extraction, warm-pressing, curing and post curing. The method has the advantages that: (1) the method has reasonable process, strong production continuity, high efficiency, low energy consumption, and no environmental pollution; (2) the manufactured bamboo macrofiber composite material has no mold and no crack, and has the density between 0.9 and 1.3g/cm<3>, thehardness between 60 and 150MPa, the static bending strength between 140 and 160MPa, the water-absorbing expansion rate between 0.3 and 2 percent, the surface wear resistance between 0.04 and 0.09g/100r, and the formaldehyde emission between 0.1 and 0.4mg/L; and (3) the invention provides a more positive production technique for reasonably utilizing the bamboo resources, so that the reconstituted bamboo timber application prospect is better.

The invention provides a preparation method of phenolic foam boards. The method comprises the steps as follows: mixing 90 to 120 parts by weight of alkaline phenolic resin, 4 to 15 parts by weight of foaming agents, 2 to 6 parts by weight of emulsifiers, 2 to 8 parts by weight of flexibilizers and 10 to 30 parts by weight of curing agents so as to prepare a foaming system of the phenolic foam boards; heating for foaming; solidifying for shaping; and then post-solidifying so as to prepare the phenolic foam boards. The post-solidifying treatment is performed on the conditions that temperature is 30 to 80 DEG C, the humidity is 40 to 90%, and the time is 24 to 72 hours. The preparation method provided by the invention is realized by post-solidifying boards, and adding an inorganic fire retardant and a high-activity modifier to the foaming system of the phenolic foam boards so as to prepare phenolic foam boards with the warping dimension being equal to or less than 4 mm, the wall-mounting condition is good or the boards are warped slightly, and no dropping phenomenon occurs; therefore, the boards accord with the requirements for good boards in the markets, and the method solves the warping problem of the phenolic foam boards.

The invention discloses a method for preparing solvent-free multicomponent polyurethane synthetic leather based on steam injection coating. The method comprises the following steps: firstly, adding polyhydric alcohol, isocyanate, chain extender, vulcanizing agent, catalyst, coupling agent, foaming agent, foam stabilizer, colorant, component absorbing carbon dioxide and water and filler into a plurality of stock tanks of a polyurethane casting machine; secondly, conveying the raw materials to a mixing head of the casting machine for mixing by regulating a metering pump on the raw material tank to obtain mixed size; coating the mixed size on release paper by a steam injection spreader, fitting base cloth on the mixed size layer of the release paper and then drying the base cloth; and finally, continuously reacting the mixed size by post curing till complete curing, and peeling the release paper after cooling to obtain the solvent-free multicomponent polyurethane synthetic leather. No solvent is used in the production process, so that the environmental pollution problem of DMF, TOL, MEK, THF and other solvents generated by the existing solvent polyurethane synthetic leather can be solved.

The invention provides a silicone hydrogel contact lens including a hydrolyzable units. The hydrolyzable units can be converted by hydrolysis into a hydrophilic units which is capable of imparting the silicone hydrogel contact lens a hydrophilic surface without post-curing surface treatment. The invention also provides an actinically crosslinkable prepolymer including hydrolyzable units and use of the prepolymer of the invention. In addition, the invention provides a method for making wettable silicone hydrogel contact lens without posterior surface treatments other than hydrolysis.

The invention discloses a thermo-curable 3D printing photosensitive resin and a preparation method and an application thereof. The photosensitive resin includes, by weight, 50-70 parts of a prepolymer, 30-50 parts of a diluent, 1-5 parts of a photo-initiator and 0.5-5 parts of a thermal-initiator, wherein the decomposition temperature of the thermal-initiator is higher than or equal to 100 DEG C when the half-life period thereof is 1 h. After photo-curing 3D printing shaping, the 3D printing photosensitive resin can be subjected to curing by heating as a post-curing method with a stable constant temperature heating device, such as a drying box and the like, so that the 3D printing photosensitive resin develops application in a non-transparent sample, a sample having complex shape, an ultra-thick sample, a colored sample and the like, and enables the samples to have better mechanical performances.

The invention provides a polyurethane rail tie plate which is a microporous polyurethane elastomer made from raw materials of a polyalcohol composition, an NCO-blocking modified isocyanate curing agent and a foaming agent. The invention further provides a preparation method of the polyurethane tie plate, comprising the following steps: adding the foaming agent to the polyalcohol composition; adding the modified isocyanate curing agent to a mixture of the polyalcohol composition and the foaming agent according to a certain proportion at the temperature of 25-60 DEG C; and stirring and evenly mixing the obtained mixture, casting for molding, curing, taking out and then post-curing to obtain the polyurethane tie plate. The dynamic-static stiffness ratio of the tie plate is not more than 1.5; fatigue tests for 3 million times show no damage to appearance of the tie plate and low dimensional change rate of not more than 30%, thus achieving good damping and cushioning effects and enhancing comfortableness when a train runs; and meanwhile the rail tie plate has good durability.

Disclosed is a resin paste for die bonding comprising a butadiene homopolymer or copolymer (A) having a carboxylic acid terminal group, a thermosetting resin (B), a filler (C), and a printing solvent (D), wherein the elastic modulus of the resin paste following drying and curing is within a range from 1 to 300 MPa (25° C.). The solid fraction is preferably from 40 to 90% by weight, the thixotropic index is preferably from 1.5 to 8.0, and the viscosity (25° C.) is preferably from 5 to 1,000 Pa·s. Using this resin paste, a semiconductor device is produced by a method comprising (1) applying a predetermined quantity of the resin paste to a substrate, (2) drying the resin paste to effect B-staging of the resin, (3) mounting a semiconductor chip on the B-staged resin, and (4) conducting post-curing of the resin.

The invention discloses a high comprehensive performance composite grinding piece which comprises a base material, grinding particles and an adhesion agent, wherein the surface of the base material is divided into a plurality of areas; the grinding particles attached to the identical areas have identical sizes; the grinding particles attached to the different areas have different sizes; the sizes of the grinding particles attached to the various areas of the base material increase gradually from the center of the base material to the edge of the base material; the grinding particles are composite grinding particles formed by compositing nano cerium dioxide particles and silicon dioxide particles; and the adhesion agent consists of a component A and a component B. The invention also provides a manufacturing method of the high comprehensive performance composite grinding piece. The manufacturing method comprises the following steps of a gluing procedure, a sand planting procedure, a post curing procedure, a flexing water carrying procedure, a laser cutting procedure, a base material deformation prevention treatment procedure and a storage procedure. The manufacturing method is simple and convenient, and is low in manufacturing cost, and the manufactured composite grinding piece has weather resistance, fatigue resistance, high temperature resistance and abrasion resistance, and is long in service life and high in polishing efficiency.

The invention discloses a preparation method of a carbon fiber reinforced carbon-silicon carbide dual-ceramic based gradient composite material. The preparation method is characterized by comprising the following steps: (a), carrying out thermal treatment onto the fibers by adopting different temperatures; (b), dipping the fibers which are not subjected to thermal treatment and the thermally-treated fibers obtained in the step (a) in resin glue liquor, drying, continuously superposing and laying up, applying a certain pressure after laying up, and carrying out curing and post-curing treatment in sequence to prepare a composite material biscuit body with fiber/base body interface adhesive strength in gradient change; (c), carrying out high-temperature pyrolysis onto the composite material biscuit body obtained in the step (b) to obtain a carbon/carbon porous body with porosity in gradient change; (d), carrying out liquid silicon permeation onto the carbon/carbon porous body obtained in the step (c) under a high temperature to obtain the C/C-SiC composite material with SiC ceramic base body content in gradient change. The preparation method disclosed by the invention is simple in process, short in preparation period, low in cost and capable of preparing a large workpiece with a complex shape.

The invention discloses a preparation method of a 1,5-naphthalene diisocyanate-based polyurethane microcellular elastomer. The preparation method comprises the following steps of: 1, dewatering polymer polyhydric alcohol by stirring under a vacuum condition at 80 to 150 DEG C; 2, under the protection of nitrogen, reacting excessive 1,5-naphthalene diisocyanate-based polyurethane with the polymer polyhydric alcohol at 100 to 150 DEG C so as to generate a prepolymer containing redundant -NCO groups; 3, performing chain extension by adopting a full pre-polymerization method, mixing a prepolymer component with a chain extender component according to a proportion, and stirring at a high speed, injecting the mixture solution into a mould of which the temperature is between 80 and 110 DEG C, and demoulding after precuring for 10 to 60 minutes, wherein the chain extender component does not contain the polymer polyhydric alcohol; and 4, post-curing the product subjected to demoulding, for 13 to 18 hours at 100 to 120 DEG C. The 1,5-naphthalene diisocyanate-based polyurethane microcellular elastomer prepared by using the method disclosed by the invention is used as a high-strength damping material for bearing dynamic fatigue, such as buffering damping components of an elevator motor and other equipment which can easily generate acting force with a certain frequency.

An electric transmission line carbon fiber composite core manufacturing method mainly includes the following steps of conducting preprocessing, dehumidification and glue infiltration, pre-hardening carbon fibers in a two-section heating mode, enabling high-strength glass fibers or basalt fibers to cover a pre-hardened carbon fiber core according to certain rules, hardening the carbon fiber core covered by the high-strength glass fibers or the basalt fibers in a three-section mode, and conducting post curing and cooling, wherein consumed epoxy resin is high-temperature-resistant special type pultrusion epoxy resin which is prepared by adding modified anhydride compounds in the glue infiltration process. The electric transmission line carbon fiber composite core manufacturing method has the advantages that the carbon fibers are preformed in a pultrusion mode to be in a semi-hardened state after being infiltrated, heating temperature sections are controlled so that the carbon fiber core with excellent performance can be obtained, particularly, heating and hardening are conducted in the three-section mode in the final covering and forming process, therefore, the rigidity of final products is ensured, the smoothness of production and production efficiency are improved, and the carbon fiber composite core produced through combination can completely meet the requirements of electric power transmission.

A via-filling material improves a via-filling process in manufacturing multi-layered printed circuit boards. The via-filling material is capable of undergoing UV pre-cure and thermal post-cure step. Exposed to ultraviolet light, the via-filling material filled up the two ends of the via form solid barrier films so that the inside via-filling material will not flow out during a thermal post curing process due to an lower viscosity of said material. The dual-cure treatment resolves the problems of polishing, sagging and bubbling in the via-filling process and ensures the integrity of the filling material. As a result, the via-filling material with smooth surface and a solid inside without void or hole therein formed.

The invention provides a method for manufacturing a thick copper PCB (Printed Circuit Board) circuit. The method comprises the steps of: a positioning hole drilling step for drilling a positioning hole in a printed board substrate; a pattern transfer step for bonding a dry film on the printed board substrate and forming patterns on the dry film; a pattern electroplating step for electroplating copper on the patterns unprotected by the dry film; a film removing step to remove the dry film; an etching step for etching the copper unprotected by lead and tin and removing the lead and tin to obtain a conductor circuit pattern of a current layer; a dielectric layer joint filling step for arranging a dielectric layer oil ink layer on all the substrate area of a circuit board; a dielectric layer grinding step for removing oil ink on a copper face; a post-curing step for curing the structure; a copper deposition electroplating step for depositing a copper deposited metal layer on a circuit copper layer and the surface filled with the dielectric layer oil ink; and a full-board electroplating step for electroplating copper on the entire circuit board. When the final thickness of copper does not reach the preset thickness of the copper, the steps from pattern transfer to full-board electroplating are executed repeatedly.

The invention discloses a green oil silk-printing method for a printed circuit board (PCB). The green oil silk-printing method comprises the following steps: preprocessing, carrying out silk-printing, pre-baking the board, exposing, developing and post-curing, wherein a flow process of carrying out silk-printing on the surface of the board, preheating, carrying out silk-printing on the hole edge of a drilled hole and preheating is adopted in the silk-printing step; in the process of carrying out silk-printing on the surface of the board and preheating, the radius of an oil blocking PAD corresponding to the drilled hole is greater than that of the drilled hole by 5 mil; in the process of carrying out silk-printing on the hole edge of a drilled hole and preheating, the radius of a printing oil window of the drilled hole is greater than that of the drilled hole by 20 mil, and a blocking point with a radius smaller than that of the drilled hole by 1 mil is arranged in the middle of the printing oil window; and the number of meshes in the silk-printed hole edge of the drilled hole is more than that of the meshes in the silk-printed board surface. According to the green oil silk-printing method for the PCB, the silk-printing requirement of not blocking a small hole by green oil can be well met, the defects of blockage of the green oil on the hole, under developing, lateral erosion in film printing and developing, a tin ring on the hole edge and a tin ball hidden in the hole after prevention of tin spraying, and the like are reduced, the PCB is good in electric property and appearance, the method is simple in process and convenient to operate, and the production efficiency is improved.

A low-temp steam curing method for in-situ cast box beam includes such steps as spraying insulating layer on external mould, laying down steam tubes, building steam curing shed, burying a temp strain gauge at each measuring point, parallelly connecting them via a switch to a reader, laying aside, heating, making temp constant, cooling and post curing. Its advantages are high speed, high strength and no crack.

The invention discloses low-fat additive-free yogurt and a preparation method thereof. The low-fat additive-free yogurt includes main ingredients such as raw milk and fermenting agent, and raw milk is degreased, concentrated, fermented with fermenting culture, cooled, counterbalanced, filled and post-cured to be made into the additive-free yogurt with low content of fat. According to the low-fat additive-free yogurt and the preparation method thereof, by increasing the content of proteins inside the raw milk and prolonging the fermentation time, partial proteins are modified, a substance with the structure and taste being similar to that of the fat is generated, and a taste of smoothness and coolness is applied to the low-fat yogurt; and through the counterbalancing processing technique, protein particles in the yogurt can be eliminated, an exquisite taste is applied to the yogurt, and the viscosity of the yogurt is greatly improved by utilizing the yogurt post-curing technique. On the premise that no external fat substitute is used and no additive such as a thickening agent and essence is utilized, the low-fat additive-free yogurt with a taste being similar to that of whole fermented milk is developed only by improving the raw material and yogurt manufacturing technique conditions.

The invention discloses a preparation method of a glass fiber enhanced thermosetting resin matrix composite material, which comprises the following steps of: one, preparing a modified thermosetting resin; two, preparing modified thermosetting resin glue solution; three, brushing the modified thermosetting resin glue solution on a glass fiber cloth; four, performing pressing and curing; and five, performing post-curing. The preparation method has a simple preparation process and is suitable for industrial production. The glass fiber enhanced thermosetting resin matrix composite material prepared by the method has excellent dielectric property, outstanding comprehensive mechanical properties, high temperature resistance and heat and humidity resistance, and can be used for high-frequency digital printed circuit boards, high-performance wave-transmitting structural materials and aero-space structural materials.