摘要:
An abrasive grain including a porous particle material in which a large number of fine particles for cutting edges form gaps partly among them and bond loosely each other. The particles for the cutting edges are produced by growing primary particles in secondary particles, which are formed by cohesion of a large number of primary particles, with a heat treatment at a temperature of forming necks at bonding points among the primary particles.
摘要:
A processing tool is used to carry out a fixed-abrasive grinding process on a surface of a silicon work-piece. The processing tool includes abrasive grains made up silica grains. A primary average grain size of the silica grains is desirably 0.8 nm to 10 &mgr;m.
摘要:
An electrolytic in-process dressing method, an electrolytic in-process dressing grinding apparatus, and an electrolytic in-process dressing grindstone, for grinding workpiece as the grindstone is being subjected to electrolytic in-process dressing, are provided, in which the grindstone is made of abrasive grains and a binding material which is capable of forming a uniform and fine passive layer at the grinding surface thereof and also capable of preventing excessive elusion of the binding material, thereby preventing the formation of chips at the ground surface in the course of grinding operation.
摘要:
A porous film is here disclosed which is obtainable by stretching a film in at least uniaxial direction, said film being formed from a resin composition containing 25 to 70 parts by weight of a polyolefin resin and 75 to 30 parts by weight of an inorganic filler; said resin composition further containing 0.5 to 10 parts by weight of dehydrated castor oil (a) and 0.01 to 5 parts by weight of hardened castor oil (b) based on the total 100 parts by weight of the polyolefin resin and the inorganic filler; and the amount of the component (a) being 20 to 95% by weight based on the total amount of the components (a) and (b). In this porous film, softness and feeling like cloth, moisture vapor transmission, uniformity of the film thickness and the like are equal to their conventional levels. Furthermore, the adhesive strength of a securing tape does not deteriorate because the third components (a) and (b) do not float on the surface of the porous film. Therefore, it can be suitably used as materials of articles such as disposable diapers fixable and attachable by securing tapes.
摘要:
Thermosetting polymers predominantly of a polybutadiene as a base polymer is disclosed, which polybutadiene is so configured as to have a vinyl content of not less than 40% by mol of the total monomer mol and a crosslink reactivity of at least 70% of the vinyl content. The cured polymer is ultrahighly resistant to heat and particularly applicable as an engineering plastics. Also disclosed is a process for producing the thermosetting polymer with the use of a specific initiator.
摘要:
A processing tool is used to carry out a fixed-abrasive grinding process on a surface of a silicon work-piece. The processing tool includes abrasive grains made up silica grains. A primary average grain size of the silica grains is desirably 0.8 nm to 10 μm.
摘要:
An abrasive grain including a porous particle material in which a large number of secondary particles contain gaps between primary particles bonded to each other. The secondary particles are produced by growing primary particles into secondary particles, which are formed by cohesion of a large number of primary particles, via a heat treatment at a temperature sufficient to form necks at bonding points between the primary particles.
摘要:
A method for converting benzene and aromatic hydrocarbon compounds having 9 or more carbon atoms contained in a material oil having a boiling point of 30˜210° C. into toluene and aromatic hydrocarbon compounds having 8 carbon atoms in the presence of hydrogen and the said catalyst. The catalyst can be obtained by carrying at least one metal or metal compound selected from Group VIII and Group VIA of the Periodic Table on a carrier containing zeolites in which maximum diameter among diameters of its micropores is 0.6-1.0 nm and a ratio of SiO2/Al2O3 is 50 or more.
摘要:
An electrolytic in-process dressing method, an electrolytic in-process dressing grinding apparatus, and an electrolytic in-process dressing grindstone, for grinding workpiece as the grindstone is being subjected to electrolytic in-process dressing, are provided, in which the grindstone is made of abrasive grains and a binding material which is capable of forming a uniform and fine passive layer at the grinding surface thereof and also capable of preventing excessive elusion of the binding material, thereby preventing the formation of chips at the ground surface in the course of grinding operation.
摘要:
There is provided thermosetting resin compositions suitable for injection molding compounds having an apparent curing rate of 0.7 and 0.008 cm/sec respectively at 170.degree. C. and 110.degree. C. by a disk cure tester and an apparent activation energy of at least 26 Kcal/mol, by the addition of fluidity modifiers selected from ether compounds having methylene ether type structure, ester compounds having methylene groups connected with carbonyl ether groups and alcohol compounds having methylene groups connected with hydroxyl groups, to phenolic resin, hexamethylenetetramine, fillers and additives.