Electronic Part Packaging Sheet Composition for Burr-Free Molding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional packaging methods for electronic devices suffer from the generation of fluffs and burrs during sheet molding, which can cause faults in electronic devices, particularly with the miniaturization of these devices.
Innovation Solution
An electronic device packaging sheet is developed with a substrate layer comprising a thermoplastic resin combined with high molecular weight (meth)acrylic acid ester copolymers and styrene-acrylonitrile copolymers, specifically within a range of 700,000-4,300,000 weight-average molecular weight, to inhibit the generation of fluffs and burrs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional thermoplastic resins are used for packaging sheets, then manufacturing is simple and cost-effective, but fluffs and burrs are generated during molding which cause faults in electronic devices
Solution Approach 1:
The patent applies composite materials by combining thermoplastic resin with specific copolymers (styrene-acrylonitrile copolymer or (meth)acrylic acid ester copolymer having weight-average molecular weight of 700,000-4,300,000) in a layered structure. This composite approach eliminates fluffs and burrs during molding while maintaining ease of manufacture through standard packaging sheet processing methods.
2Reliability
If polyolefin or styrene-butadiene-styrene block copolymer is blended in substrate layer, then burr and fluff generation is reduced, but the reduction is insufficient and film formability deteriorates
Solution Approach 1:
The patent applies parameter changes by specifying precise parameters for the copolymer components: weight-average molecular weight of 700,000-4,300,000 and specific monomer compositions (styrene-acrylonitrile copolymer with 25-75 mass% acrylonitrile or (meth)acrylic acid ester copolymer with 4-8 carbon number alkyl group). These controlled parameter changes achieve both effective burr/fluff reduction and maintained film formability.
Solution Approach 2:
The patent uses composite materials with specific composition ratios (thermoplastic resin 70-99 mass%, copolymer 1-30 mass%) to simultaneously achieve burr and fluff reduction while preserving film formability. The layered composite structure allows each material to contribute its advantageous properties.
3Reliability
If high molecular weight copolymers are used to inhibit burrs and fluffs, then defect generation is reduced, but processing difficulty increases
Solution Approach 1:
The patent optimizes processing ease by controlling the molecular weight parameter within 700,000-4,300,000 and specifying precise copolymer compositions. This parameter optimization ensures that while burr and fluff generation is effectively inhibited, the materials remain processable using conventional packaging sheet manufacturing methods.
Data Source
AI summary
An electronic device packaging sheet including a substrate sheet having at least one substrate layer including: a thermoplastic resin (I); and a resin (II) which includes at least one copolymer selected from a (meth)acrylic acid alkyl ester copolymer (A) and a styrene-acrylonitrile copolymer (B) that have a weight-average molecular weight of 700,000-4,300,000. The substrate sheet has at least one substrate layer comprising the thermoplastic resin (I) at 70-99 mass % and the resin (II) at 1-30 mass %.