材料类型 Material Type | 制造商 Vendor | 颜色 Color |
| 无胶柔性覆铜板 2L FCCL | 台虹Taiflex、生益Shengyi、新扬Thinflex、松下Panasonic、杜邦Dupont、新日铁NSCC | 琥珀Amber、透明Transparent |
| 有胶柔性覆铜板 3L FCCL | 台虹Taiflex、生益Shengyi、杜邦Dupont | 琥珀Amber |
| 保护膜 CL | 台虹Taiflex、生益Shengyi、杜邦Dupont、韩华Hanwha | 琥珀Amber、黑色Black、白色White |
| 覆铜板 CCL | 生益Shengyi、南亚Nanya、伊索拉Isola、罗杰斯Rogers | 白色Whtie、黄色Yellow、黑色Black、棕色Brown |
| 阻焊油墨 Soldermask | 太阳Taiyo、日保丽NPT、新东方New east | 绿色Green、橙色Orange、蓝色Blue、 白色White、黑色Black |
纯胶粘结片 Bonding Sheet | 台虹Taiflex、杜邦Dupont、华烁Haiso、东溢Dongyi | 白色White |
| 带基材粘结片 Bondply | 杜邦Dupont | 琥珀Amber |
| 半固化片 Prepreg | 斗山Doosan、生益Shengyi、伊索拉Isola、南亚Nanya | 白色Whtie、黄色Yellow |
| 层Layer | 类型type | 制造商Vendor | 厚度Thickness |
导体 Conductor | 压延RA、高延展性压延HA | 日矿JX、福田Fukuda、奥林Olin | 6um~6oz |
电解ED、高温延伸电解HTE | 三井Mitsui、古河Furukara 长春CCP、南亚Nanya | 2um~5oz | |
铜镍合金 Copper-Nickel | 汉密尔顿HPM、Special metals | 待定 TBD | |
胶 Adhesive | 亚克力Acrylic、环氧Epoxy | 台虹Taiflex、杜邦Dupont、华烁Haiso、 东溢Dongyi | 10um~100um |
基底或绝缘介质层 Base or Dielectric | 聚酰亚胺PI | 杜邦Dupont、达迈TaimideSKC、钟渊Kaneka | 0.5mil~5mil |
热塑性聚酰亚胺TPI 改性聚酰亚胺MPI | 钟渊Kaneka、宇部UBE、杜邦Dupont | 0.5mil~7mil | |
聚萘二甲酸乙二醇酯PEN | 杜邦Dupont | 待定 TBD | |
聚对苯二甲酸乙二醇酯PET | 杜邦Dupont | 1~4mil | |
| 聚四氟乙烯PTFE | 杜邦Dupont | 2~4mil | |
| 液晶聚合物LCP | 可乐丽Kuraray | 2~4mil |
Profile Features | Polyimide | Liquid/Epoxy | Liquid/ Polyimde |
Flexibility | Good | Short life | Good |
Heat Resistance | High | Low | High |
Electrical Properties | Good | * | * |
Registration Accuracy | High | Low | Very high |
Technical Hurdle | High | High | Very High |
Storage Condition | Room Temp. | Refrigerator | Freezer |
Cost | High | Low | High |
| Type | Features |
| Electro-deposited(ED) Copper foil | General application,suitable for static or low flexing requirements |
| Roll-annealed(RA) Copper foil | High flexing ability,suitable for dynamic application |
Copper is sandwiched between dielectric base material and coverlay, the identical circuits protection materials position the circuits pattern in a mechanically neutral zone.
Rolled annealed (RA) copper is recommended for high dynamic application such as optical pick-up head, printer head and disk drive because of its superb flexural endurance characteristic.
It should be borne in mind that most flexible circuits are customised three dimensional interconnection systems with one-time fixing and do not require high flexural endurance. Therefore Electro-deposited Copper (E.D. copper) is adequate for most applications. Another alternative copper type which is gaining popularity is the use of Dyncamically Flexing ED Foils, or DF ED. It offers typically more controllable etch rates and straighter trace walls which is sometimes compatible to RA foils with lower cost.
The selection of copper type will depend on the current carrying and other electrical requirements of the circuit. Conductor materials other than copper are also available. Other conductor materials are available such as aluminium, nickel, nichrome and beryllium copper.
While these other materials are available, their use is very rarely called for.
Material Name | Application | Features |
Acrylic(Thermal set) | Suitable for SMT, reflow and greater bonding strength required areas, also used for multi-layer flex lamination. | Resist high temperature, high adhesiveness,heat lamination required |
PSA(Pressure Sensitive Adhesive) | General application such as stiffener attachment. | Low heat resistance,no heat lamination required,more cost effective |
PSA(resist heat) | To replace Acrylic for better process control | PSA with better heat resistance |
Various adhesive systems available for copper foil lamination to based material; coverlay lamination; stiffener lamination and heat sink lamination depending on heat resistance, flexural endurance, bonding strength and etc. PSA (Double sided tape) can be attached to flex with liner, remove the liner only upon installation to casing or other flex assembly.
The use of a pressure sensitive adhesive is often worth consideration if product cost is an important factor and where the performance requirements permit.
Material Name | Application | Features |
FR4(Fire Retardant 4 Hours) | For component mounting or insertion,resist high temperature(reflow) | Suitable for SMT with high dimensional stability |
FR2(Fire Retardant 2 hours) | For component mounting or insertion, resist high temperature (reflow) | Suitable for SMT with high dimensional stability |
PI(Polyimide Stiffener) | For component mounting or insertion,resist high temperature(reflow) | Suitable for SMT and ZIF connectors with high dimensional stability |
PET(Polyester Stiffener) | For ZIF connector insertion | Lower heat resistance,not fit for SMT or reflow |
Stiffener is used to rigidize the selective areas of FPC in order to enable electronic components insertion or mounting.Other usage including thickness adjustment to suit ZIF(Zero Insertion Force)connectors.
POLYESTER
Polyester is a relatively inexpensive material compared with Polyimide. With a upper operating temperature limit of 80¡ãC and a maximum short temperature duration of 150¡ãC, this material has good electrical and mechanical properties with low thermal expansion rate at low and normal temperatures.
Upper heat resistance limitation of 150¡ãC generally restricts its use to applications where mechanical connections are made for soldered joints. Soldering can cause delamination, and requires a high degree of skill with the soldering iron. Direct contact with the heated iron will shrink or melt the material. Apart from its low cost, the greatest advantage of polyester is in common with other thermo plastic materials.
Polyester is not a suitable material for multilayer flex and reflow process but they are fit for antenna coil of smart card application.
POLYIMIDE
(RAW MATERIAL FOR COVERLAY, BASED MATERIAL & POLYIMIDE STIFFENER)
The combination of polyimide film and a high temperature thermo-setting resin adhesive produces a flexible system having excellent mechanical and electrical properties and is substantially unaffected by temperature change. Heat applied during manufacture and subsequent reflow or soldering processes tends to increase the adherence rather than weakening the conductors.
Although the adhesives used do not have the same temperature properties as the polyimide film itself, the construction offers a continuous operating temperature of 150C and a maximum short duration temperature of 300C Subject to material type). Polyimide has a low thermal expansion (0.02-0.04mmC-1m-1)and very high tensile strength (1.69MNm-2) and is compatible with conventional epoxy-glass laminates. Thus, polyimide is applicable for rigid/flexible combinations and to multilayer applications using both plated through hole and clearance layer techniques.
Polyimide thermoset is readily hand, dip or wave soldered and it can be unsoldered and resoldered many times. Before wave or dip soldering it is desirable to oven bake for one hour at 80Celsius to 110Celsius. The most commonly used thicknesses are 12.5 microns(0.0005") and 25 microns (0.001") and 50 microns (0.002"); other thicknesses are available.
This material can be used in the majority of applications, is obtainable in a flame retardant grade and is highly recommended.
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