摘要:
A copolyester film is disclosed which comprises a copolyester in which the dicarboxylic acid component comprises 100 to 85 mole percent of terephthalic acid and the diol component comprises 65 to 97 mole percent of 1,4-butanediol and 3 to 35 mole percent of a polyethylene glycol with a molecular weight of 106 to 550. The copolyester has a reduced viscosity in the range of 0.8 to 1.4 dl/g as measured at a concentration of 0.5 g/dl in a 1:1 (by weight) solvent mixture of phenol and tetrachloroethane at 30.degree. C. The copolyester has a main endothermic peak with a peak maximum temperature of 160.degree. C. to 200.degree. C. and at least one subsidiary endothermic peak with a peak maximum temperature of 30.degree. C. to 80.degree. C. in differential scanning calorimetry with the ratio (R) of the area occupying not less than 40.degree. C. in the subsidiary endothermic peak, the main endothermic peak area being within the range of 3 percent to 20 percent.A hot melt adhesive comprising the copolyester film and a method for producing the copolyester film are also disclosed. The hot melt adhesive has a high initial modulus of elasticity at high temperature (30.degree.-50.degree. C.) and features improved processability or workability while retaining the required properties of a hot melt adhesive.
摘要:
Polycarbonate resin compositions are disclosed, comprising: (1) (A) a polycarbonate resin and (B) polyesterether elastomer, said elastomer composing of a bifunctional carboxylic acid component and a glycol component comprising polyalkylene glycol and ethylene glycol, or (2) the components (A) and (B), and (C) a rubber-like elastomer, or (3) the components (A) and (B), and (D) a polyester resin, or (4) the components (A), (B), (C) and (D). These compositions are excellent in solvent resistance and so forth, and further possess excellent physical and thermal properties characteristic of a polycarbonate resin. Thus the compositions are useful for use in production of industrial and electrical articles, such as a car bumper in the field of car industry.
摘要:
A polycarbonate resin composition which comprises(i) bisphenol type aromatic polycarbonate, in admixture with(ii) 5 to 200 parts by weight of a polyester type copolymer, per 100 parts by weight of said bisphenol type aromatic polycarbonate, which is produced by adding(a) 5 to 100 parts by weight of bisphenol type aromatic polycarbonate having a viscosity-average molecular weight of not less than 5,000,to (b) 100 parts by weight of a polyester precursor having a number-average polymerization degree of 1 to 30 which is obtained from bifunctional carboxylic acid mainly composed of terephthalic acid or a derivative thereof having an ester forming ability and a diol component, and effecting polycondensation, which provides an improved fluidity and solvent cracking resistance without remarkably decreasing of the original impact resistance and transparency of polycarbonate, to eliminate the defects of polycarbonate.
摘要:
A process for producing a novel polyester polyurethane having excellent hydrolysis resistance and excellent flexibility at low temperature, which is obtained from a polyisocyanate and a polyester polyol which is obtained by reaction a dicarboxylic acid with a mixture of 1,9-nonanediol and a polyol represented by the formula ##STR1## wherein R.sup.1 denotes methyl group or ethyl group, R.sup.2 denotes hydrogen atom, methyl group, ethyl group, hydroxymethyl group or hydroxyethyl group, and n is an integer of 1 to 5, said polyester polyol having an average molecular weight of 500 to 30,000.
摘要:
In the preparation of a polyurethane from a polymeric polyol and an organic polyisocyanate, by using as the polyol a polymeric polyol containing in the molecule thereof 2-methyl-1,8-octanediol residue, a novel polyurethane having excellent resistance to hydrolysis, low temperature characteristics and abrasion resistance can be obtained.
摘要:
A nonvolatile semiconductor memory device according to embodiment includes: a semiconductor substrate having an upper portion being partitioned into a plurality of semiconductor portions extending in a first direction; a charge storage film provided on the semiconductor portion; a word-line electrode provided on the semiconductor substrate and extending in a second direction intersecting with the first direction; and a pair of selection gate electrodes provided on both sides of the word-line electrode in the first direction on the semiconductor substrate and extending in the second direction, a shortest distance between a corner portion of each of the semiconductor portions and each of the selection gate electrodes being longer than a shortest distance between the corner portion of the semiconductor portion and the word-line electrode in a cross section parallel to the second direction.
摘要:
A semiconductor memory device includes a first active region, a second active region, an element isolation region, memory cell transistors. Each of memory cell transistors includes a laminated gate and a first impurity diffusion layer functioning as a source and a drain. The laminated gate includes a first insulating film, a second insulating film, and a control gate electrode. The second insulating film is commonly connected between the plurality of memory cell transistors to step over the element isolation region and is in contact with an upper surface of the element isolation region. An upper surface of the element isolation region is higher than a bottom surface of the first insulating film and is located under the upper surface of the first insulating film.
摘要:
A semiconductor memory device includes gate electrodes extending in a first direction above a surface of a substrate. The semiconductor memory device also includes a reinforcement insulation film formed in a line shape and extending in a second direction crossing the gate electrodes in a plane view viewed from above the surface of the substrate, and connected to adjacent gate electrodes. Further, the semiconductor memory device includes an interlayer dielectric film provided between the adjacent gate electrodes, and having a void inside.
摘要:
Polyurethane compositions comprising a polyurethane synthesized by reacting a diol, a specific alicyclic diisocyanate, a specific alicyclic diamine and hydrazine or isophthalic acid dihydrazide in specific proportions and a solvent therefor have good solution stability and, when applied as coating compositions, give coats with good light stability, good surface properties, high softening points and sufficient flexibility at low temperatures.
摘要:
A nonvolatile semiconductor memory of an aspect of the invention includes memory cells in the memory cell forming area, and select gate transistors in the select gate forming area. Each memory cell has two first diffusion layers formed in a semiconductor substrate, a first gate insulating film formed on the semiconductor substrate, a charge storage layer formed on the first gate insulating film, a first intermediate insulating film formed on the charge storage layer and a first gate electrode formed on the first intermediate insulating film. Each select gate transistor has two second diffusion layers formed in the semiconductor substrate, a second gate insulating film formed on the semiconductor substrate, a second intermediate insulating film formed in direct contact with the second gate insulating film and having the same structure as the first intermediate insulating film, and a second gate electrode formed on the second intermediate insulating film.