Abstract: Process for preparing polyalkyl-2-alkoxy-7-hydroxychroman derivative of the general formula (V): ##STR1## wherein R.sup.1 denotes lower primary alkyl, R.sup.2 denotes hydrogen or lower primary alkyl and R.sup.3 denotes loweralkyl, by reacting resorcin with either an aliphatic ketone of the general formula (I): ##STR2## wherein R.sup.1 and R.sup.2 are as defined above, and an alcohol of the formula (II):R.sup.3 OH (II)wherein R.sup.3 is as defined above, in the presence of an acid catalyst, or an aliphatic ketone acetal of the general formula (III): ##STR3## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined above, in the presence of an acid catalyst.

Abstract: The present invention is directed to optically active compounds each containing a naphthalene skeleton, and to liquid crystal compositions which contain the aforesaid optical active compounds, these compositions being suitable for ferroelectric liquid crystal devices having excellent photostability and chemical stability and having a rapid responsivity.

Abstract: A laminated plate for a high frequency comprising a reinforced plastic layer and a conductive layer bonded to an outermost layer of the reinforced plastic layer, wherein the reinforced plastic layer comprises reinforcing fibers impregnated with poly(4-methyl-1-pentene) at least partially graft-modified with an unsaturated carboxylic acid or a derivative thereof.

Abstract: In accordance with the present invention, semiconductor devices are produced by the process involving the steps of obtaining a core-box resin molded item integrated with a lead frame by coating said lead frame on its portions expected to be in non-contact with said core-box resin molded item with an organic high molecular substance having a melting or softening point higher than the molding temperature of the resin constituting said core-box resin molded item and soluble in a solvent which does not dissolve said core-box resin molded item, placing the thus coated lead frame in position within a mold and injecting the resin into the mold thereby carrying out injection or transfer molding and immersing the lead frame bearing core-box resin molded item obtained in the foregoing step in said solvent to remove by dissolving said organic high molecular substance.

Abstract: Disclosed is a mortar.concrete composition comprising a polymer emulsion, a portland cement material and an aggregate, which is characterized in that the polymer emulsion is one prepared by neutralizing a seed polymer with an acid or a salt or by quaternizing it with a quaternizing agent, the surfaces of the emulsion grains being thereby highly densely cationated, where the seed polymer is formed by adding a monomer as represented by the following formula (I) or a mixture of the monomer (I) and copolymerizable ethylenic unsaturated monomer(s) to a seed latex of a carboxyl-modified synthetic rubber latex or synthetic resin emulsion and polymerizing them: ##STR1## The polymer of the invention may noticeably reinforce the strength of the shaped product even when the amount of the polymer added is small.

Abstract: A method of preparing a paper having a reinforced strength wherein a polymer latex is added to a paper stock in an amount of from 2.5 to 30% by weight. The polymer latex is prepared by neutralizing a seed polymer with an acid or a salt or by quaternizing it with a quaternizing agent. The surfaces of the emulsion grains are provided with a large number of cationic groups. The seed polymer is formed by adding a monomer represented by the following formula (I) or a mixture of the monomer (I) and copolymerizable ethylenic unsaturated monomer(s) (II) to a seed latex of a carboxyl-modified synthetic rubber latex or synthetic resin emulsion and polymerizing them: ##STR1## R.sub.1 represents H or CH.sub.3 ; R.sub.2 represents an alkylene group having from 2 to 5 carbon atoms;R.sub.3 and R.sub.4 each represents H or an alkyl group having from 1 to 5 carbon atoms;A represents ##STR2## and R.sub.1, R.sub.3 and R.sub.4 are so selected that the monomer is hardly soluble or insoluble in water.

Abstract: Polyimide which is obtained by polymerization and consists essentially of recurring structural units of the formula (I): ##STR1## wherein X is a single bond or a hexafluoroisopropylidene group, is processed to a form of pellet, followed by heat-treating to obtain crystallinity of 5% or more, and fed to an extruder to obtain articles.

Abstract: A process for producing m-phenoxybenzyl alcohol by reacting chlorobenzene with m-hydroxybenzyl alcohol in the presence of a copper catalyst and a base, the process being characterized by using an alkylene glycol as a reaction solvent.

Abstract: In accordance with the present invention, there is provided a bubble-containing ehtylene/.alpha.-olefin rubber excellent in kneadability, characterized in that the ethylene/.alpha.-olefin rubber prepared by copolymerization of 50-95 mol% of ethylene, 5-50 mol% of .alpha.-olefin having at least 3 carbon atoms and 0-10 mol% of non-conjugated polyene contains 5-1000 parts by volume, based on 100 parts by volume of said rubber, of bubbles and has a water absorption volume as measured in accordance with ASTM D 1506 of less than 20% by volume of the total bubble volume.

Abstract: The novel fluorine-containing mono- or poly-alkylene glycol of this invention is a mono- or poly-alkylene glycol of the formula (I): ##STR1## wherein R.sup.1, R.sup.2 and R.sup.

Abstract: The 5-substituted hydantoins represented below can be transformed into D-.alpha.-amino acids by the use of the cultured broth, cells or treated cells of the genus Hansenula:5-substituted hydantoins: ##STR1## wherein R represents an alkyl, substituted alkyl, phenyl or substituted phenyl group.D-.alpha.-amino acids: ##STR2## wherein R represents the same meanings as above.

Abstract: A process for the preparation of N-substituted maleimides by conducting heat-dehydration and dehydrating imidization of N-substituted maleamic acids under azeotropic distillation of generated water in a solvent mixture containing a solvent capable of forming water azeotrope and an organic aproptic polar solvent, in the presence as catalyst of metallic tin, tin oxide, a tin salt of a maleamic acid or a tin compound which forms a thin salt of the N-substituted maleamic acid in the reaction system.

Abstract: There is provided a novel organic hydroperoxide, 3-(2-hydroperoxy-2-propyl)phenol. The hydroperoxide is produced by oxidizing 3-(2-hydroxy-2-propyl)phenol or m-isopropenylphenol with hydrogen peroxide in the presence of an acid catalyst.There is further provided a method of producing resorcinol which comprises decomposing the 3-(2-hydroperoxy-2-propyl)phenol in the presence of an acid catalyst.

Abstract: A mixed cleaning solvent containing dichlorotrifluoroethane and dimethoxymethane without containing Flon #113, which is suitable for cleaning and degreasing printed circuit boards and for eliminating flux residues and dust particles adhering thereon and which reveals high cleaning ability without occurrence of whity specks of volatilization residues including ionic residues on the treated surface with possible attainment of high stability to decomposition of the solvent component.

Abstract: A powder feeder for continuous casting is provided with a powder container for storing casting powder in the final stage prior to being supplied onto a molten steel surface, and a spreading feeder for spreading the casting powder on the molten steel surface in a mold. The powder container is arranged above the head of an operator in the operator work area, the spreading feeder is supported and manipulated by a robot arm, and powder is supplied to the spreading feeder from the discharge port of the powder container through a flexible transfer path which can follow the movement of the robot arm.

Abstract: A copper powder for electroconductive paints comprising copper particles and an organic zirconate compound which has been applied as a coating on the surfaces of said particles and an electroconductive paint composition obtained from the copper powder for electroconductive paints. The organic zirconate compounds used in the present invention are an organic zirconate compound (RO).sub.x --Zr--(OR').sub.4-x having an easily hydrolyzable organic group and an organic group which is hardly hydrolyzable and exhibits lipophilicity or a mixture of a zirconium acylate polymer and a higher carboxylic acid ester.

Abstract: A toner resin contains a specific polymer as its principal component. The polymer is obtained by mixing 20-80 parts by weight of a low molecular polymer having a number average molecular weight of 1,000-5,000 and a glass transition temperature (Tg) of 40.degree.-75.degree. C., 80-20 parts by weight of a vinyl monomer, 0.01-5 parts by weight of a polymerization initiator and 0-3 parts by weight of a crosslinking agent, dispersing the resultant mixture in an aqueous system and then polymerizing same. The toner resin has excellent low-temperature fixing property and offsetting resistance, can provide marks of superb vividness, and also can prevent modifications of copied marks, for example, due to transfer of a plasticizer.

Abstract: A method for producing a cast of titanium or a titanium-based alloy by fusing titanium or a titanium-based alloy containing an alloy element in a vacuum furnace while introducing argon gas therein and casting the resultant melt in mold, which method is characterized by adjusting the introduction of the argon gas so that the argon gas pressure (atm) in the furnace assumes the following magnitude proportionately to the alloy element content M (% by weight):Not less than 2.1 when 0.ltoreq.M<5Not less than 1.6 when 5.ltoreq.M<10Not less than 1.5 when 10.ltoreq.M<15Not less than 1.2 when 15.ltoreq.M.

Abstract: The lock device for a vehicle in accordance with the present invention comprises a synthetic resin body fixed to a door and equipped with a recess formed on its right side; a latch fitted rotatably into the recess; a striker fixed to a car body and having a front leg portion having a small diameter and meshing with the latch, a rear side leg portion having a large diameter and a wedge-like bridge portion connecting the tips of the leg portions and having a thin front portion and a thick rear portion; a guide groove formed on the body and permitting the entrance of the striker; front side clamp means disposed on the front side of the guide groove, for clamping the front side of the striker; and rear side clamp means disposed on the rear side of the guide groove, for clamping the rear side portion of the striker. A swell portion defining the guide groove is formed integrally on the back side of the body and a metallic back plate is fixed to this back side.

Abstract: Disclosed is an epoxy resin composition comprising, as basic components, (A) an epoxy resin, (B) a phenol-novolak resin, (C) a curing promotor and (D) a filler. Pulverized or spherical silica having specific particle size characteristics is used as the filler (D). Preferably, a halogenated epoxy resin and antimony oxide are further incorporated in this epoxy resin. This epoxy resin composition shows a very small molding shrinkage. If a dialkylurea derivative is used as the curing promotor (C), the stability of the composition at about 100.degree. C. is drastically improved and the flowability of the composition is improved. Accordingly, precision injection molding becomes possible, and the effect of sealing a semiconductor is enhanced.