めっき技術

Engineering plastics

Engineering plastics have taken root as the generic name of plastics excelling in thermal resistance and mechanical characteristics. From the aspect of performance, it is defined as being 500kgf/cm2 in tensile strength, 20,000kgf/cm2 in bending elasticity, and 100°C or higher in long-term thermal resistance. Engineering plastics with higher thermal resistance are called super engineering plastics. The purposes of plating these plastics include [1] weight reduction and cost reduction [2] ease of molding and degree of freedom in product design, [3] upscale appearance of products by metal texture, [4] improvement of hardness and frictional damage resistance, [5] giving electrical conductivity, and [6] improvement of gas barrier properties, and [7] improvement of thermal resistance, weather resistance and contamination resistance.
Category Type (Crystalline resins are marked with a circle (○).)
Thermoplastic resins

[General-purpose resins] long-term heat-proof temperature 50°C - 100°C
acrylonitrile butadiene styrene resin (ABS), acrylonitrile styrene resin (AS), polyvinyl chloride resin (PVC), ○ polyethylene (PE), polystyrene (PS), polypropylene (PP), methacrylate resin (PMMA)

[General-purpose engineering plastics] long-term heat-proof temperature 100°C - 150°C
○ polyamide (PA) [nylon], ○ polyacetal (POM), polycarbonate (PC), PC+ABS, ○ polybutylene terephthalate (PBT), ○ polyethylene terephthalate (PET), modified polyphenylene ether (m-PPE) [modified PPO Noryl]

[Special engineering plastics] long-term heat-proof temperature 150°C - 200°C
polyetherimide (PEI), polyether sulfone (PES), polysulfone (PSF), ○ polyphenylenesulfide (PPS)

[Super engineering plastics] long-term heat-proof temperature 200°C - 300°C
○ liquid-crystal polymer (LCP), polyarylate (PAR), polyamide-imide (PAI), polyimide (PI), ○ polyetheretherketone (PEEK), polyphthalamide (PPA)

[Other resins]
○ polytetrafluoroethylene (PTFE) [tetrafluoride resin], ultra high molecular weight polyethylene (UHMWPE) thermal plastic elastomer, polymethylpentene (PMP), biodegradable plastic

Thermosetting resins alkyd resin, epoxy resin (EP), diallyl phthalate resin (PDAP), silicone resin (SI), phenol resin (PF), ○ unsaturated polyester resin (UP), polyurethane (PU), melamine resin (MF), urea resin (UF)
採用事例
Engineering plastics
Plating for special engineering plastic (molded printed circuit board)
Appearance of electroless copper → electro copper → nickel → gold plating on polyetherimide
(From “Denki Mekki Gaido” edited by Federation of Electro Plating Industry Association, Japan)