Mitsui Petrochemical Industries, Ltd.

Mitsui Chemicals, Inc.

Shigeru Katayama

Kaoru Tominaga

Takayuki Nakano

Junichi Yoshitake

Izuru Yokoyama

Katsuhiko Tasaka

Nobuyuki Takeda

Yoshiyuki Iwase

Kazumi Matsumoto

Mutsuhiro Aoki

Toshio Suetsugu

A process for manufacturing a package of a semiconductor device, and providing a semiconductor device in which a vapor-impermeable moistureproof plate is embedded in a bottom surface of a hollow package or an inner surface wallthicknesswise therefrom to provide moisture-proofness.

Method of manufacturing a semiconductor device with an airtight space

This invention relates to a package construction of a semiconductor device, and provides a semiconductor device in which a vapor-impermeable moistureproof plate is embedded in a bottom surface of a hollow package or an inner surface wallthicknesswise therefrom to provide an excellent moisture-proofness in terms of the package construction.

Semiconductor device with an airtight space formed internally within a

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. On that account, flashes of the resin formed on the lead frame can be removed with facility or the formation of said flashes can be suppressed without damaging the resin molded portion, whereby a good electrical connection between the lead frame and the semiconductor element can be accomplished.

Method of removing flash from a semiconductor leadframe using coated

Disclosed are a polynuclear polyhydric phenol represented by the following general formula [I]: ##STR1## wherein R.sup.1 and R.sup.2 stand for a hydrogen atom or a lower alkyl group, R.sup.3 stands for a hydrogen atom, an alkyl group, an aryl group or a halogen atom, and n is an integer of from 0 to 10, and a polyepoxy compound consisting of a polyglycidyl ether of this polynuclear polyhydric ether. When this polyepoxy compound is combined with a curing agent, a curable epoxy resin composition excellent in the heat resistance characteristics is provided.

Polyglycidyl ethers of polynuclear polyhydric phenols

A process for producing a hydrocarbon resin having improved color and thermal stability, which comprises treating a petroleum cracking or reforming fraction containing cationically polymerizable hydrocarbons and not more than 0.7% by weight, based on the fraction, of cyclopentadienes and having a boiling range of from 140.degree. C. to 280.degree. C., with 0.8 to 3.0 moles, per mole of the cyclopentadienes, of a dienophile compound having a carbon-to-carbon double bond and a carbonyl or cyano group adjacent to the double bond; and then polymerizing the treated petroleum fraction in the presence of a polymerization catalyst.

Process for producing hydrocarbon resins having improved color and

A hydrocarbon resin having improved color and thermal stability is prepared from a petroleum cracking or reforming fraction containing cationically polymerizable hydrocarbons and having a boiling range of 140.degree. to 280.degree. C. The petroleum fraction is first heat-treated with an .alpha., .beta.-unsaturated dicarboxylic acid anhydride at 50.degree. to 250.degree. C., and then polymerized in the presence of a catalyst. The hydrocarbon resin is useful as a binder component in hot-melt adhesives, pressure-sensitive adhesives and thermofusible traffic paints.

A process for producing a hydrocarbon resin (C) which comprises copolymerizing 100 parts by weight of vinyl aromatic hydrocarbons (A) containing more than 80% by weight isopropenyltoluene and from about 5 to 100 parts by weight of a fraction (B) which is the by-product of cracking or refining petroleum and mainly comprising unsaturated hydrocarbons having a boiling point ranging from about -15.degree.C to 45.degree.C and having 4 to 5 carbon atoms in the presence of a Friedel-Crafts catalyst and pressure-sensitive adhesives comprising the hydrocarbon resin produced in combination with a rubber.

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Sodegaura, Japan

Shigeru Katayama