JPS60248722A - Casting composition - Google Patents

Abstract

PURPOSE:A casting composition that contains oligomers bearing radically polymerizable double bonds, monomers and a photo-polymerization initiator, thus being suitable for use in light emitting diode sealing, because it has shortened curing time and causes no corrosion of the lead wires. CONSTITUTION:The objective composition contains (A) oligomers bearing radically polymerizable double bonds such as epoxy resin, urethane resin (meth)acrylate, unsaturated polyester, preferably they are clear, (B) monomers such as methyl methacrylate, ethylene glycol di(meth)acrylate, and (C) a photo-polymerization initiator, preferably hydroxycyclohexyl phenyl ketone, preferably in an amount of 0.5-5wt%.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a casting composition used when resin-sealing a light emitting diode by casting.

[Background technology]

Generally, in order to protect light emitting diodes from the external environment, transparent epoxy resin and acid anhydride curing agents are used to encapsulate the LEDs by transfer molding or casting, but the curing time is several tens of minutes to a few minutes. It takes several hours, and there is a problem that the phosphor bronze of the lead wire of the light emitting diode is attacked by the acid or basic substance of the hardening agent, causing a patina.

[Purpose of the invention]

An object of the present invention is to provide a casting composition for resin-sealing a light-emitting diode, which has a short curing time and is free from corrosion of the lead wires of the light-emitting diode.

[Disclosure of the invention]

The present invention relates to a fill casting composition characterized by containing an oligomer having a radically polymerizable unsaturated double bond, a polymer, and a photopolymerization initiator, and the present invention will be described in detail below.

The oligomer having an unsaturated double bond that can be radically polymerized to be used in the present invention may be an oligomer that has an unsaturated double bond that can be radically polymerized with epoxy resin, acrylate or methacrylate of urethane resin, unsaturated polyester V resin, etc. Although not particularly limited, it is preferable that the material be transparent. As a chemical agent, Meta V methacrylate, butitoshi methacrylate,
Hydroxythiol methacrylate, ethylene glycol di(meth)acrylate, polyethylene glycol di(
meth)acrylate, trimethylo-Vpropane tri(meth)acrylate, pentaerythritol tri(meth)
Acrylate, styrene, vinylene, etc. are used, and preferably transparent ones are used. As a photopolymerization initiator, penzoin methyl ether M,
Penzoin ethyl ether V, benzoin isopropyl ether, benzine, benzophenone, acetophenone,
Anthraquinone, 2-ethyl γ-anthraquinone, benzyl methyl ket-M, hydroxycyclohexy V-pheniM ketone, jetoxyacetophenone, etc. are used, but are not particularly limited, but preferably do not cause new synthesis such as yellowing after curing. In this respect, it is desirable to choose a photopolymerization initiator that does not cause any discoloration, and hydroxycyclohexylphenylated ketone and jetoxyacetophenone are preferred photopolymerization initiators because they cause little discoloration. The amount of photopolymerization initiator added is 0.5 to 0.5 to the total composition.
It is desirable to add 5% by weight (simply written as %). Note that casting compositions containing these components do not exclude those containing coupling agents, pigments, and fillers, and may be added as appropriate and used.

Examples that specifically support the effects of this invention will be given below.

Example: Acrylate monomer (manufactured by Osaka Organic Chemical Co., Ltd., trade name Visco-) to 50 parts by weight (hereinafter simply referred to as parts) of epoxy acrylate resin (manufactured by Dainichisue Ink Chemical Co., Ltd., trade name UE-8200) 190) A casting composition containing 50 parts of a photopolymerization initiator (manufactured by Chipa Geigy, trade name: IM Gacure 184) was poured into a transparent polymethyV-pentene resin mold in which a light emitting diode was set. Thereafter, when it was irradiated with ultraviolet rays using a high-pressure mercury lamp of 80 W/Cm 2 , it was cured in 20 seconds at an irradiation dose of ago m j /cd, and no corrosion of the lead wires of the light emitting diode was observed at all.

Conventional example epoxy resin (manufactured by CieM Chemical Co., Ltd., product name Ko Pico)
) 82B) A casting composition prepared by adding 80 parts of methihymic acid anhydride to 100 parts was poured into a silicone resin mold in which a light emitting diode was set, and then heated at 160° C. for 5 hours to cure it. However, a patina appeared on the lead wire of the light emitting diode.

[Effects of the Invention] As shown in Examples and Conventional Examples, the curing time of the casting composition of the present invention was short and there was no corrosion of the lead wires of the light emitting diode, confirming the superiority of the present invention.

patent applicant Matsushita Electric Works Co., Ltd. Representative Patent Attorney Toshimaru Takemoto (and 2 others)

Claims (1)

[Claims] (1) A casting composition characterized by containing an oligomer and polymer having a radically polymerizable unsaturated double bond and a photopolymerization initiator. (2> The casting composition according to claim 1, wherein the oligomer and the polymer have transparency.