At present, China's large-scale use of CCL has the following types, its characteristics are as follows: CCL type, CCL knowledge, copper clad plate classification methods are many.

(CEM series), laminated multilayer board base and special material base (ceramic, metal core (common aluminum substrate), etc.) can be divided into: paper base, glass fiber cloth base, composite base (CEM series) ) Five categories.

(XPc, XxxPC, FR-1, FR-2, etc.), epoxy resin (FE-3), polyester (P-1), polyester-based resin, Resin and other types. Common glass fiber cloth CCL has epoxy resin (FR-4, FR-5), which is the most widely used glass fiber cloth type. In addition, there are other special resins (glass fiber cloth, polyamide fiber, non-woven fabrics to increase the material): bismaleimide modified triazine resin (BT), polyimide resin (PI) , Diphenylene ether resin (PPO), maleic anhydride imide-styrene resin (MS), polycyanoate resin, polyolefin resin, and the like.

According to CCL flame retardant performance classification, can be divided into flame retardant (UL94 a V0, UL94 a V1 level) and non-flame retardant (UL94 a HB class) two types of boards.

Over the past two years, with the emphasis on environmental issues, in the flame retardant CCL and separate a new non-brominated species of CCL species, can be called "green flame retardant cCL". With the rapid development of electronic products, cCL have higher performance requirements. Therefore, the performance classification from CCL is divided into general performance CCL, low dielectric constant CCL, high heat resistance CCL (general plate L above 150 ℃), low thermal expansion coefficient CCL (generally used for packaging substrate ) And other types. With the development of electronic technology and continuous progress, the PCB substrate materials continue to put forward new requirements, thus promoting the continuous development of copper clad plate standards.

At present, the main criteria for substrate materials are as follows:

International standards: Japan's JIS standard, ASTM, NEMA, MIL, IPc, ANSI, UL standard, British Bs standard, German DIN, VDE standard, French NFC, UTE standard, Canadian CSA standard, Australia AS standard, the former Soviet Union's FOCT standards, the international IEC standards, etc .; PCB design materials suppliers, common and commonly used to have: Health \ Kingboard \ International and so on.

PCB circuit board sheet description: According to the brand quality level from bottom to high divided as follows: 94HB-94VO-CEM-1-CEM-3-FR-4

Detailed parameters and uses are as follows:

94HB: ordinary cardboard, no fire (the most low-grade materials, die punching, can not do power board)
94V0: flame retardant cardboard (die punching)
22F: single-sided semi-glass plate (die punching)
CEM-1: single-sided glass fiber board (must be computer drilling, can not die)
CEM-3: double-sided half-glass plate (in addition to double-sided cardboard outside the dual-sided low-end material, a simple double-sided panel can use this material, FR-4 will be cheaper 5 to 10 yuan /
FR-4: double-sided glass plate

1. Flammability characteristics of the classification can be divided into 94VO-V-1-V-2 -94HB four
2. A prepreg: 1080 = 0.0712 mm, 2116 = 0.1143 mm, 7628 = 0.1778 mm
3. FR4 CEM-3 is the plate, fr4 is the glass fiberboard, cem3 is the composite substrate
4. Halogen-free refers to the halogen does not contain (bromine iodine and other elements) of the substrate, because the bromine in the combustion will produce toxic gases, environmental requirements.
5. Tg is the glass transition temperature, ie melting point.
6. The circuit board must be flammable, can not be burned at a certain temperature, only soften. At this time the temperature point is called the glass transition temperature (Tg point), this value is related to the PCB board size and durability.

What is a high Tg? PCB circuit boards and the advantages of using high-Tg PCBs:

High Tg Printed Circuit Board When the temperature rises to a certain threshold, the substrate changes from "glassy" to "rubbery", where the temperature is called the glass transition temperature (Tg) of the plate. That is, Tg is the highest temperature (° C) at which the substrate remains rigid. In other words, ordinary PCB substrate material at high temperatures, continue to produce softening, deformation, melting and other phenomena, but also in the mechanical, electrical characteristics of the sharp decline, this way to affect the product life, the general Tg of 130 Higher than Tg, generally higher than 170 ℃, medium Tg is greater than about 150 ℃; usually Tg ≥ 170 ℃ PCB printed circuit board, known as high Tg printed circuit board; substrate Tg increased, the printed board heat resistance, Resistance to moisture, chemical resistance, stability and other characteristics will improve and improve. The higher the TG value, the better the temperature resistance of the sheet, especially in the lead-free process, high Tg applications are more; high Tg refers to the high heat resistance. With the rapid development of the electronics industry, especially in the computer as the representative of the electronic products, toward the high functionality, high multi-layer development, PCB substrate material needs higher heat resistance as a prerequisite. To SMT, CMT as the representative of the emergence and development of high-density installation technology, the PCB in the small aperture, fine line, thin, more and more inseparable from the substrate high heat resistance support.

Therefore, the difference between the general FR-4 and the high Tg is the same as that of the high Tg, and the mechanical strength, dimensional stability, adhesion, water absorption, thermal decomposition, thermal expansion and the like of the material under heat, especially after heat absorption There are differences in the situation, high Tg products significantly better than ordinary PCB substrate material.