摘要:
A screen for projection television set comprising a foamed support and a reflective film adhered to the concave side of the support, said support having the outer layers with a high density such as 0.7 to 1.2 g/cm.sup.3 and the inner portion with a low density so as to make the density of the foamed support as a whole 0.2 to 0.5 g/cm.sup.3, has good projection properties, surface hardness with sufficiently strong support. When said support is foam molded by using a polyurethane having special polyol components, its heat resistance is remarkably increased and can be foam molded at high temperatures without deformation.
摘要翻译:一种用于投影电视机的屏幕,包括发泡支撑体和粘附到支撑体的凹侧的反射膜,所述支撑体具有高密度的外层,例如0.7至1.2g / cm 3,密度低的内部部分 为了使发泡载体的密度整体为0.2〜0.5g / cm 3,具有良好的投影性能,表面硬度具有足够坚固的支撑。 当所述载体通过使用具有特殊多元醇组分的聚氨酯进行泡沫模塑时,其耐热性显着增加,并且可在高温下进行泡沫模塑而不变形。
摘要:
Rigid polyurethane foams having excellent heat resistance and impact resistance can be produced with good workability due to good flow properties by using a composition comprising a polyol, a polyisocyanate, a blowing agent and a reaction accelerator as essential component, characterized by using as the polyol, a mixture of (a) an alkylene oxide adduct of 4,4'-diaminodiphenylmethane having OH value of 280-600 mg KOH/g, (b) an aliphatic polyether having a hdyroxyl value of 450-800 mg KOH/g and 3 or 4 hydroxyl groups in the molecule, and (c) a polyether having a hydroxyl value of 30 to 100 mg KOH/g and 2 or 3 hydroxyl groups in the molecule, in limited amounts.
摘要:
A composition for polyurethane foam comprising (a) polyols containing at least one of alkylene oxide adducts of aniline-formaldehyde condensates and alkylene oxide adducts of reduced compounds of nitrated toluenes in an amount of 30 to 70% by weight of the polyols, (b) at least one isocyanate of the formula: ##STR1## a fire retardant, together with one or more conventional catalysts, foam stabilizers, blowing agents and the like additives, can give fire retardant, high impact and heat resistant urethane foams.
摘要:
In a composition for producing polyurethane foam which comprises an organic polyisocynate compound, a compound having at least one active hydrogen atom in the molecule, a foaming agent and a catalyst as essential components, an aminoalkylsilane represented by the following general formula is contained: ##STR1## wherein n is 1 or 2, and R.sub.1 to R.sub.5 are alkyl groups. By use of such a catalyst polyurethane foam having a even color distribution and excellent mechanical properties is produced.
摘要:
Integral skin polymethane foams can be produced in a short time by impingement mixing a solution comprising polyols containing as an essential component a polyol derived from aromatic amine, a blowing agent and a special catalyst of tertiary amine salt having a hetero ring in the molecule, with a solution comprising one or more polyisocyanates, followed by injection into a closed mold and foaming and curing therein.
摘要:
Cases for automobile air conditioners or car-loaded refrigerators are molded in an integrated structure of a body part and fixing parts by reaction injection molding from a mixture of a liquid A comprising 20-60% by weight of an aliphatic amine-based polyol, 30-60% by weight of a PO adduct of 4,4'-diaminodiphenylmethane and 15-40% by weight of an ordinary polyol and further containing a foam-controlling agent, a foaming agent and a catalyst and a liquid B comprising polyisocyanate as obtained through impingement.
摘要:
A reaction injection molded article formed with threads and a method of molding same, wherein threaded members, such as threaded inserts, helicoils, etc., are positioned in the cavity of a reaction injection mold, and molding material is injected into the cavity to form the threaded members into a unitary structure with a body of the reaction injection molded article. The threaded members are securedly held in place by a surface layer of relatively high density. The molding material is a mixture of an A liquid and a B liquid, the A liquid containing 100 weight parts of polyether polyol obtained by adding alkylene oxide to various kinds of alcohol or amine, 1-5 weight parts of a reaction promoting agent (catalyst) comprising tertiary amines, tin compounds, etc., 3-50 weight parts of water and a foaming agent, such as low boiling point alkylhalide, 1-5 weight parts of a foaming regulating agent, such as alkylene oxide denatured polydimethyl siloxane and 1-20 weight parts, if necessary, of pigment, dyestuff and filler, such as carbon black, diazo compound, silica, glass fiber, etc., and the B liquid containing 100-200 weight parts of MDI, TDI, crude MDI or crude TDI.
摘要:
A thick and thin film hybrid multilayer wiring substrate includes an adjustment layer provided between a thick film circuit and a thin film circuit in order to adjust positions of the thick film circuit and the thin film circuit with high integration and large area of the thick and thin film hybrid substrate. The adjustment layer is formed using a direct printing process in accordance with dispersion of the shape of the thick film circuit substrate to absorb the dispersion of the substrate. Further, in order to absorb dispersion of contraction of the thick film substrate due to sintering, a position of a mark provided on the substrate is detected by an electron beam and thereafter a connection pattern is formed to be connected to a regular pattern.
摘要:
A cooling device for cooling semiconductor elements by removing heat generated from the semiconductor elements such as, for example, semiconductor integrated chips in a large-sized electronic computer. The cooling device is fashioned of a composite AlN-BN sintered material having a Vickers hardness not higher than one-fifth of that of an AlN material, and an anisotropic property of thermal conductivity in a two dimensional direction is higher than that of AlN which is isotropic in thermal conductivity. The cooling device may be mass-produced while nevertheless having a high transfer performance matching the quantity of heat generated for each semiconductor element even if the composite sintered material is uniform in shape and size. The composite sintered material is formed by a mixture of a hexagonal BN powder having an average particle diameter of not less than 1 .mu.m and an AlN powder having an average particle diameter of about 2 .mu.m, with a sintering aid being added and the powdery mixture being subjected to a hot press sintering whereby the sintered material is low in thermal conductivity in a direction parallel to an axis of a shaft of the hot press.
摘要:
An optical switch having a small number of optical connections includes a substrate in which are provided a first light path for conducting optical signals and a second light path consisting of a photosensitive element and light emitting element in pairs. An optical fiber cable is interrupted by the substrate, and optical signals in the fiber cable are transmitted through the first light path or intervened by an electrical system through the second light path in response to the switching movement of the substrate.