Abstract:
In heat-expandable microspheres as a starting material for hollow fine particles, which have excellent performances required for giving not only a durability in steady running region but also a durability in high-speed running region to a tire-rim assembly, and each consisting of an outer shell made of a thermoplastic resin obtained by polymerizing a monomer component in the presence of a polymerization initiator, and a foaming agent encapsulated in the outer shell and having a boiling point not higher than a softening point of the thermoplastic resin, the polymerization initiator comprises a peroxydicarbonate as an essential component, and the foaming agent comprises a fluorine-containing compound having an ether structure and a carbon number of 2-10 and containing no chlorine atom and bromine atom.
Abstract:
When a second detector determines that a character image has a halftone (YES in #1) and a third detector (48) determines that a font size of the character image is equal to or greater than a threshold value β and equal to or smaller than a threshold value α (YES in step #4), a fourth detector determines whether a presently focused pixel constitutes a particular portion of a character (step #5). When the fourth detector determines that the pixel data of the presently focused pixel constitutes the particular portion of the character (YES in step #5), the image processing section sets the pixel data to be subjected to a second screen processing which is performed at a higher gradation level (step #6).
Abstract:
An angle detecting head provided with an emitter and a pair of receivers is rocked, and a bent surface of a workpiece bent by a punch and a die of a bending machine is irradiated with a measurement light from the emitter, a reflected light is received by the pair of receivers, and a bending angle of the workpiece is obtained from a peak value of the light received by the respective receivers. The angle detecting head is movable parallel to the die, is movable in a direction close to and away from the workpiece, and is movable in a direction in which the die is raised/lowered. The angle detecting head is positioned in an optimum angle measurement position of the workpiece and the bending angle is measured. Moreover, the bending machine presses the workpiece to the vicinity of a target angle, measures the bending angle of the workpiece during final pressing, removes pressure to bring the workpiece to an unloaded state, measures the bending angle of the workpiece, and obtains and stores a difference between the final pressing angle measured value and the unloaded angle measured value as a spring-back amount.
Abstract:
An epoxy resin composition comprising (A) a biphenyl skeleton epoxy resin, (B) a biphenyl skeleton phenolic resin as a curing agent, (C) molybdenum compound, and (D) an inorganic filler is suited for semiconductor encapsulation since it is effectively moldable and cures into a part having improved reflow crack resistance, moisture resistance, and flame retardance. It does not pose a hazard to human health or the environment.
Abstract:
A semiconductor encapsulating epoxy resin composition is provided comprising (A) an epoxy resin, (B) a phenolic resin curing agent, (C) a microencapsulated flame retardant comprising a red phosphorus-base core coated with a thermoplastic resin and/or thermosetting resin, (D) a molybdenum compound, and (E) an inorganic filler. The composition and its cured product have moisture-proof reliability and high flame retardance despite the absence of halogenated epoxy resins and antimony oxide.
Abstract:
An epoxy resin composition contains (A) an epoxy resin having an epoxy equivalent of at least 185 and possessing a skeleton having a structure in which two benzene rings are conjugable to each other directly or via an aliphatic unsaturated double bond, carbon atoms having an atomic orbital of SP.sup.2 type accounting for at least 50% of the carbon number, (B) a phenolic resin having a hydroxyl equivalent of at least 160, carbon atoms having an atomic orbital of Sp.sup.2 type accounting for at least 85% of the carbon number, (C) a polyimide resin in an amount of 1-20 parts by weight per 100 parts by weight of components (A) and (B) combined, and (D) 70-85% by volume of the entire composition of an inorganic filler. The composition cures into products having flame retardancy and high-temperature reliability even though it is free of bromine compounds and antimony compounds.
Abstract:
An epoxy resin composition comprising (A) a naphthalene ring-containing epoxy resin, (B) a biphenyl-containing epoxy resin, (C) a specific phenolic resin, and (D) an inorganic filler shows good flow and cures to products having low modulus of elasticity, especially at temperatures above Tg, a low coefficient of expansion, high Tg irrespective of low stresses, and minimized water absorption. Then semiconductor devices encapsulated with the present composition remain highly reliable even after being subject to thermal shocks upon surface mounting.
Abstract:
An epoxy resin having a propenyl group conjugated with an aromatic ring is heat resistant and is easily molded and cured into products having high strength and Tg. It is thus useful as a resin component or modifier.
Abstract:
A method that heat-expandable microspheres includes the use of a shell of thermoplastic resin and a non-fluorine blowing agent encapsulated therein having a boiling point not higher than the softening point of the thermoplastic resin. The method includes, a step of dispersing an oily mixture containing a polymerizable component, the blowing agent, and a polymerization initiator containing a peroxydicarbonate in an aqueous dispersing medium to polymerize the polymerizable component contained in the oily mixture. The resultant heat-expandable microsphres have a shell which is less apt to become thinner than its theoretical value, contain minimum amount of resin particle inside their shell, and have excellent heat-expanding performance.