Gold Finger Copper 1mm Single Sided PCB Circuit Board Blue Oil

The development history of
Before the printed circuit board appeared, the interconnection between electronic

components is a direct wire connection to form a complete circuit.Now, circuit

breadboards exist only as effective experimental tools, and printed circuit boards

have become an absolute dominant position in the electronic industry.
At the beginning of the 20th century, in order to simplify the production of

electronic machines, reduce wiring between electronic parts and reduce production

costs, people began to study the method of replacing wiring with printing.Over the

past thirty years, engineers have been proposing to use metal conductors as wiring on

insulating substrates.
The most successful was in 1925, when Charles Ducas of the United States printed a

circuit pattern on an insulating substrate, and then successfully established

conductors for wiring by electroplating.
It wasn't until 1936 that Austrian Paul Eisler published his foil-film technology in

England. He used a printed circuit board in a radio device;In Japan, palace this

pleased help to spray the attached wiring method "メ タ リ コ ン blowing wiring method

(chartered 119384)" success to apply for a patent.Of the two, Paul Eisler's method is

the most similar to today's printed circuit boards. This process, called subtraction,

removes unwanted metals.Charles Ducas and Yoshinosuke Miyamoto did this by adding only

the wiring needed, which is called the addition method.However, due to the high heat

of electronic parts at the time, the two substrates were difficult to use together, so

it was not used formally, but also made the printed circuit technology further.
In 1941, copper paste was painted on talc for wiring in the United States to make

proximity fuse.
In 1943, the Americans introduced the technology to military radios.
In 1947, epoxy resin began to be used to make substrates.At the same time, NBS began

to study the printing circuit technology to form coils, capacitors, resistors and

other manufacturing technologies.
In 1948, the United States officially approved the invention for commercial use.
In the 1950s, low-heat transistors took the place of vacuum tubes in large numbers,

and printed circuit plate technology began to be widely used.At that time to etch foil

film technology as the mainstream.
In 1950, Japan used silver lacquer on glass substrate for wiring;And phenolic resin

based paper phenolic substrate (CCL) with copper foil for wiring.
In 1951, with the advent of polyimide, the heat resistance of the resins was further

improved, and the polyamide substrate was also manufactured.
In 1953, Motorola developed the electroplated through-hole method of two panels.This

method was also applied to later multilayer circuit boards.
Printed circuit boards were widely used for 10 years after the 1960s, its technology

also increasingly mature.Since Motorola's dual panel came out, multi-layer printed

circuit boards began to appear, so that the ratio of wiring and substrate area is even

higher.
In 1960, V. Dahlgreen made a flexible printed circuit board with a metal foil film

printed with the circuit pasted on a thermoplastic plastic.
In 1961, the Hazeltine Corporation in the United States adopted the electroplating

through hole method to produce multilayer plates.
In 1967, published "Plated-up technology", one of the methods.
In 1969, FD-R made flexible printed circuit boards from polyimide.
In 1979, Pactel published one of the layer addition methods, the "Pactel Method".
In 1984, NTT developed the "Copper Polyimide Method" for thin film circuits.
In 1988, Siemens developed an additional layer printed circuit board for Microwiring

Substrate.
In 1990, IBM developed layered printed Circuit boards for the "Surface Laminar

Circuit" (SLC).
In 1995, Matsushita developed Alivh's laminated printed circuit board.
In 1996, Toshiba developed BIT's plus-layer printed circuit board.
In the late 1990s, when many additional layer printed circuit board schemes were put

forward, additional layer printed circuit boards were also formally used in large

numbers until now.

PCB packaging 

1. The PCB circuit board needs to be vacuum packed with colorless gas bead plastic

bags, and the bags should be attached with necessary desiccant and ensure that the

bags are tightly packed.Can not contact with wet air, avoid PCB circuit board surface

spray tin, gold deposition and welding pad parts are oxidized and affect the welding,

is not conducive to production.
2. When packing the PCB circuit board, it is necessary

to surround the box with a layer of bubble film. Because the bubble film has good

water absorption, it can absorb water and moistureproof.In addition, moisture-proof

beads can be placed in the case.
3, put the PCB circuit board classification,

label.After sealing, the box must be kept away from the wall and the floor.Store in a

dry, ventilated place and avoid direct sunlight.
4, the warehouse temperature of PCB

circuit board storage is best controlled at 23±3℃, 55±10%RH, under such conditions,

gold, gold, tin spraying, silver plating PCB circuit board surface treatment can

generally be stored for 6 months, silver, tin, OSP surface treatment PCB circuit board

can be stored for 3 months.
5, for a long time do not use the PCB circuit board, it is

best to brush a layer of three anti paint, three anti paint can be moisture-proof,

dustproof, anti oxidation.In this way, the storage life of PCB circuit board will be

increased to 9 months.
About the PCB board several kinds of packaging, introduced to

this.In fact, the storage time of PCB circuit board is related to the surface

treatment. Gold plating and electric gold plating are the longest storage time. Under

the conditions of constant temperature and humidity, they can be stored for two or

three years.Do a good job of PCB circuit board storage can better extend the service

life of the circuit board, is a problem can not be ignored.