Abstract: A present invention provides a printed board connector, a contact thereof and a mating instrument that prevent deterioration of electrical conductivity and spring property of contacts resulting from solder rising and/or flux rising. A printed board connector can be mounted in a printed circuit board and constitutes a mating instrument in connection with a male connector such as an insulation displacement plug. The connector has a housing and a contact arranged in the housing. The contact includes a pair of forks opposing each other, terminals capable of being soldered to the printed circuit board, and a spacer connecting terminals and the pair of forks together. The spacer provides a predetermined distance between terminals and the pair of the forks to prevent solder and/flux from rising to the forks.

Abstract: A mounting structure of a card connector includes a connector body surface mounted on a wiring circuit board. An IC card can be withdrawably inserted into the connector body so that the IC card can be connected to the wiring circuit board through the connector body. The connector body includes a card insertion space which is disposed at an angle of inclination with respect to an upper surface of the wiring circuit board. A card inlet/outlet port is formed at an upper inclination end of the card insertion space such that the IC card inserted into the card insertion space through the card inlet/outlet port is retained for connection at an angle of inclination.

Abstract: A silicone rubber composition comprising an organopolysiloxane containing at least two alkenyl radicals and having a degree of polymerization of at least 100, an organopolysiloxane or organosilane, reinforcing silica, and an alkali metal salt of phosphoric acid has minimized plasticity recovery with time and improved storage stability and cures with an organic peroxide or addition reaction curing agent into a silicone rubber having improved compression set and yellowing resistance.

Abstract: Silanol group-containing organosilicon compounds having a low average degree of polymerization are prepared in an efficient and inexpensive manner by adding water at pH 1-5 to an organooxysilane, mixing them, thus forming a hydrolyzed organooxysilane mixture, and adding a mono- and/or di-alkali metal salt of phosphoric acid to the mixture so as to give pH 5-9.

Abstract: A card connector that reliably holds an inserted card with a compact mechanism to prevent the falling of the card due to unexpected external forces. The card 10 is formed with the recess 18 to receive the locking portion. The elastic locking piece 50 is mounted to the eject member 41 that slides together with the card 10 as the card is inserted or retracted. The locking piece guide means 50b, 61 converts the motion of the eject member 41 in the card insertion/retraction direction into the motion of the locking portion 50c of the elastic locking piece 50 toward or away from the card so that the locking portion 50c is engaged in the recess 18 during the card insertion and, during the card ejection, is disengaged from the recess 18.

Abstract: An organopolysiloxane gum is prepared by polymerizing a cyclic organopolysiloxane with a low molecular weight linear organopolysiloxane end-blocked with a triorganosilyl group in the presence of a thermally decomposable catalyst. After the polymerization reaction, the catalyst is deactivated by heating the reaction product under a subatmospheric pressure of typically up to 500 mmHg.

Abstract: An organopolysiloxane gum is continuously prepared by (I) mixing at least one cyclopolysiloxane with an end capping agent, (II) feeding the mixture to a self-cleaning reactor along with a polymerization catalyst of thermal decomposition type, and effecting polymerization at a temperature of 80-130° C., (III) heating the reaction mixture of step (II) at a temperature of 130-200° C. under subatmospheric pressure for deactivating the catalyst, thereby terminating the polymerization reaction, and (IV) continuously removing the cyclopolysiloxane and volatile components from the reaction product.

Abstract: In a first step, basic components including (A) 100 parts by weight of an organopolysiloxane gum, (B) 5-100 parts by weight of a reinforcing silica filler, and (C) 0.1-30 parts by weight of a processing aid are fed batchwise to a closed mixer for mixing them until uniform. In a second step, the mixture is continuously fed into a kneader/extruder for heat treating. The first step achieves quick dispersion and cooperates with the second step for the efficient production of a heat-curable silicone rubber compound.

Abstract: In a first step, basic components including (A) 100 parts by weight of an organopolysiloxane gum, (B) 5-100 parts by weight of a reinforcing silica filler, and (C) 0.1-30 parts by weight of a processing aid are fed batchwise to a closed mixer for mixing them at a temperature of room temperature to 150.degree. C. In a second step, the mixture is fed into a kneader/mixer for heat treating at a temperature of 150-250.degree. C. The first step achieves quick dispersion and cooperates with the second step to form a heat-curable silicone rubber compound in an efficient manner.

Abstract: A silicone rubber is prepared from a silicone rubber compound comprising (A) an organopolysiloxane having an average degree of polymerization of at least 100, (B) a reinforcing silica filler, and (C) an organohydrogenpolysiloxane by mixing component (C) with components (A) and (B) and heating them at a temperature of at least 100.degree. C. to form the silicone rubber compound, adding an organic peroxide or a platinum group metal catalyst to the compound, and crosslinking the compound. The silicone rubber exhibits a minimal difference in physical properties between primary vulcanization and secondary vulcanization.

Abstract: A card contacting construction includes a floating member capable of movement upwardly and downwardly in a generally vertical direction with respect to a direction of insertion of a card. The floating member is lowered in the generally vertical direction by being pushed by the card when the card is inserted contacts are arranged so as to be contacted under pressure with electrode pads which are arranged on a lower surface of the card, and the contacts are pushed down by the lowering floating member, so as to shift downwardly to preload an upwardly-directing resilient force.

Abstract: Disclosed is a material capable of readily developing natural patina, comprising a basis material made of Cu or a Cu alloy at least on the surface; and a layer of at least one compound selected from the group consisting of CuCl, CuBr and CuI formed on the surface of said basis material, and also a process for producing such material, which comprises anodizing the surface of a basis material made of Cu or a Cu alloy at least on the surface in an aqueous solution containing at least one kind of halogen ion selected from the group consisting of Cl.sup.-, Br.sup.- and I.sup.-. This material develops natural patina in a very short time after exposure outdoors.

Abstract: The process comprises the steps of (A) mixing a base material (A-1), which is obtained by mixing an organopolysiloxane and a reinforcing silica and then heating the resulting mixture, with an aminosilane compound (A-2) represented by the formula:(R.sup.1).sub.n Si[N(R.sup.2).sub.2 ].sub.(4-n)wherein a plurality of R.sup.1 may be the same or different and are each a substituted or unsubstituted monovalent hydrocarbon group, a plurality of R.sup.2 may be the same or different and are each a substituted or unsubstituted monovalent hydrocarbon group, and n is 2 or 3; to allow them to react; and (B) heating the reaction mixture obtained in the step (A) under normal pressure or reduced pressure to remove an unreacted aminosilane compound and a by-product amine, contained in the reaction mixture.

Abstract: Hydrolysis of an alkoxysiloxane of the formula: R.sup.1.sub.a (R.sup.2 O).sub.b SiO.sub.(4-a-b)/2 wherein R.sup.1 is a monovalent hydrocarbon group, R.sup.2 is an alkyl group having 1 to 4 carbon atoms, letter a=0 to 2.2, b=0.2 to 3, 2.ltoreq.a+b.ltoreq.3, and the number of silicon atoms in a molecule is 2 to 5, is effected in the presence of a cation exchange resin by adding water therereto in an amount of 1 to 10 mol per mol of the alkoxy group in the alkoxysiloxane and agitating the mixture. Low molecular weight, linear organosiloxanes having a silanol terminal group including dimer diol and trimer diol are produced in high yields.

Abstract: The silicone rubber composition of the present invention comprises (A) an organopolysiloxane obtained by mixing and heating an organopolysiloxane having a silanol group at both ends of the molecular chain and a silane or a siloxane having two hydrolyzable groups in the molecule, (B) a finely divided silica, and (C) a curing agent. The composition, wherein the content of low-molecule siloxanes is remarkably constrained, is quite useful in the application wherein low-molecular siloxanes are obnoxious, for example, in the application of electrical contacts and parts used adjacent thereto, roll materials of copying machines, gaskets for construction, etc.

Abstract: A method of producing a silicone rubber composition, comprising heating a mixture of an organopolysiloxane having a silanol group at both the ends of the molecular chain, a end blocking agent, such as a triorganosilanol, a silane or a siloxane having two dialkylaminosilyl groups in the molecule, and a reinforcing filler thereby carrying out chain lengthening and end blocking of said organopolysiloxane. According to this method, a silicone rubber composition whose low-molecular siloxane content is held down remarkably can be produced without consuming a large amount of energy for the mixing.

Abstract: A manufacturing method of organosilanes having silanol groups which is characterized by mixing organoalkoxy silanes, having at most a 20 ppm content of chlorine, expressed by the general chemical formula (1) below:Si(R.sup.1).sub.m (R.sup.2).sub.n (OR.sup.3).sub.k (1)wherein each of R.sup.1 and R.sup.2 is either a substituted or unsubstituted monovalent hydrocarbon group; R.sup.3 is an alkyl group of 1 to 4 carbon atoms; subscripts m and n are 0, 1, 2, or 3; k is either 1 or 2; and the sum of subscripts m+n+k=4, with ion-exchanged water having an electroconductivity of at least 10.sup.10 M.OMEGA., then further adding a macro-porous cation-exchange resin with a pore volume measured by the mercury injection method of at least 0.1 ml/g to the said mixture, followed by stirring of the mixture and removal of the cation-exchange resin.

Abstract: A siloxane gum is prepared by adding a silane or siloxane having two hydrolyzable groups in a molecule to a silanol-terminated organopolysiloxane in such an amount to give a molar ratio of silanol group/hydrolyzable group of from 0.5 to 3 and effecting condensation polymerization. The resulting organopoly-siloxane has a degree of polymerization of higher than 1,000 and a minimized content of low-molecular weight cyclic siloxanes of less than 5,000 ppm.

Abstract: Organopolysiloxanes having a silanol group at both terminal ends of molecular chain thereof are brought into condensation reaction with each other in the presence of a silane or siloxane having at least two dialkylaminosilyl groups per molecule as a condensation catalyst and a triorganosilanol or other endblocking agent, to lengthen the chain of the organopolysiloxane under reaction, whereby a triorganosilyl-endblocked organopolysiloxane with a high polymerization degree is obtained. The process yields a triorganosilyl-endblocked high-polymerization-degree organopolysiloxane while effectively suppressing or preventing the formation of low-molecular-weight siloxanes.

Abstract: A process for preparation of a linear organopolysiloxane having a hydroxyl group at both molecular ends thereof, comprising the steps of: mixing a dialkoxysilane having the following general formula (1):Si(R.sup.1)(R.sup.2)(OR.sup.3).sub.2 (1)wherein R.sup.1 and R.sup.2 are each a substituted or unsubstituted monovalent hydrocarbon group, and R.sup.3 is a methyl or ethyl group, or a partial hydrolyzate of said dialkoxysilane with an aqueous acid solution of ph 1.0-5.0, thereby permitting hydrolysis and condensation to take place; adding a metal oxide to the reaction mixture to adjust the reaction system to pH 6.0-9.0; and removing water and by-produced alcohols from the reaction mixture. By the process, linear organopolysiloxanes having a hydroxyl group at both molecular ends thereof can be prepared extremely easily from dialkoxysilanes, such as dimethoxydimethylsilane, which are inexpensive.