Basic knowledge of PCB copper foil
1、 Brief introduction of copper foil
Copper foil: a kind of cathode electrolytic material, a thin, continuous metal foil deposited on the substrate of PCB, which is used as the conductor of PCB. It is easy to adhere to the insulating layer, accept the printing protection layer, and form the circuit pattern after corrosion. Copper mirror test: a corrosion test of flux using a vacuum deposited film on a glass plate.
Copper foil is made of copper plus a certain proportion of other metals. Generally, there are two kinds of copper foil: 90 foil and 88 foil, that is, the copper content is 90% and 88%, and the size is 16 * 16cm. Copper foil is the most widely used decorative material.
2、 Product characteristics
Copper foil has low surface oxygen characteristics, can be attached to various substrates, such as metal, insulation materials, etc., with a wide range of temperature. It is mainly used in electromagnetic shielding and antistatic. It is used to place conductive copper foil on the substrate surface, and combines with metal substrate, which has excellent conductivity and provides the effect of electromagnetic shielding. It can be divided into: self adhesive copper foil, double guide copper foil, single copper foil, etc.
Electronic copper foil (purity is over 99.7%, thickness is 5um-105um) is one of the basic materials of electronic industry. The electronic information industry develops rapidly. The use of electronic copper foil is increasing. The products are widely used in industrial calculators, communication equipment, QA equipment, lithium-ion battery, civil television, video recorder, CD player, copier, telephone, cold and warm air conditioning Electronic parts, game machines, etc. for automobiles. The demand for electronic copper foil, especially high performance electronic grade copper foil, is increasing in domestic and foreign markets. Relevant professional organizations predict that by 2015, China’s domestic demand for electronic grade copper foil will reach 300000 tons, and China will become the largest base of printed circuit board and copper foil in the world, and the market of electronic copper foil, especially high-performance foil, is optimistic.
3、 Global supply of copper foil
Industrial copper foil can be divided into two categories: RA copper foil and point solution copper foil (ED copper foil). Among them, calendered copper foil has better ductility and other characteristics, which is used in the early soft plate process, while electrolytic copper foil has the advantage of * * lower cost than that of calendering copper foil. Because the calendering copper foil is an important raw material of soft plate, the improvement of the characteristics and price change of the calendering copper foil have certain influence on the soft plate industry.
Because there are few manufacturers of calendering copper foil and are also in the hands of some manufacturers in technology, the customer has low grasp of price and supply. Therefore, it is feasible to replace the calendered copper foil with electrolytic copper foil without affecting the performance of the products. However, if the physical characteristics of the structure of copper foil will affect the etching factors in the next few years, the importance of calendering copper foil will be increased again due to telecommunication consideration in the thin or thin products.
There are two obstacles to the production of calendering copper foil, the resource obstacle and the technical obstacle. The obstacle of resources refers to the need for copper raw material support for the production of calendered copper foil, and it is very important to occupy resources. On the other hand, technical barriers discourage more new entrants. Besides calendering, surface treatment or oxidation treatment is also the same. Most of the global factories have many technology patents and key technologies know how, increasing barriers to entry. If the new entrants adopt the post-treatment production, they are also subject to the cost system of the large factories, and it is not easy to successfully join the market, so the global calendering copper foil is still a strong exclusive market.
4、 Development of copper foil
Copper foil is an important material for CCL and PCB * in English. In the rapid development of electronic information industry, electrolytic copper foil is called “neural network” for signal transmission and communication of electronic products. Since 2002, the production value of PCB in China has entered the third place in the world. As the substrate material of PCB, copper clad board has become the third largest producer in the world. Therefore, the industry of electrolytic copper foil in China has made rapid progress in recent years. In order to understand and understand the past, present and future of the development of the world and China’s electrolytic copper foil industry, the development of the industry association of epoxy resin in China is reviewed.
From the perspective of the production department and market development of electrolytic copper foil industry, it can be divided into three development periods: the initial stage of the founding of the world copper foil enterprise and the beginning of the electrolytic copper foil industry in the United States; The period of Japanese copper foil enterprises monopolizing the world market in an all-round way; The period of multipolarization in the world competing for market.