JPS60263494A - Method of producing recording electrode plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is applicable to recording units of facsimiles, printers, grotteurs, etc., using methods such as electrostatic recording, current thermal recording, and discharge destruction recording. The present invention relates to a method of manufacturing the recording electrode plate used.

This recording electrode plate has an electrode section with a large number of conductors arranged in parallel at regular intervals on the edge of the substrate (normal conductor density 8 to 12 pieces/mm), and the other end of the conductor is connected to the drive circuit. It is used by connecting.

(Prior Art) Conventionally, as recording electrode plates, there have been known those using etched copper-clad #layer plates and those using insulated wires.

Insulated wire is used, for example, by wrapping the insulated wire in a coil around a cylindrical flexible substrate, fixing the part that will become the electrode part with resin, and cutting this part in the axial direction.
The entire cross section of the insulated wire is exposed to serve as the electrode part, a flexible board is made into a flat shape, and the other end of the insulated wire is connected to the drive circuit by soldering one by one.

Therefore, it takes a lot of time to solder the terminals, resulting in high costs. It also requires skill to ensure the reliability of soldering.

The copper clad laminate fii'i etching method is to form a copper clad laminate with an etching resist and to form a circuit sound having a parallel circuit group with a line density of 8 to 12 lines per 11 mRO by etching. Has some defects〇(1) Ordinary copper foil is 65
Because it is as thick as 100 μm, it is extremely difficult to etch it below 100 μm, and a linear density of 5 lines/712 lines/film can be obtained, but since the cross-sectional area (dot) of the circuit becomes smaller, the printing density becomes thinner.

(6) Disconnections and short circuits occur due to dents and scratches on the copper foil surface that occur during the manufacturing process of copper-clad laminates, resulting in poor yields.

From this type of ink, it is suitable for forming fine patterns by using the additive method, which forms circuit sounds by plating on the necessary areas, rather than the etching method, but at present, the copper splatter phenomenon, in which plating precipitates in unnecessary places, is used. and has excellent plating resistance,
Due to the development of highly stable resists, lines smaller than 70 μm (line density 7 lines/mm) cannot be formed.

(Objective of the invention) Is the object of the invention high linear density? The present invention provides a method for producing a recording electrode plate that can be stably obtained.

(Structure of the Invention) The present invention forms a resist on a copper plated layer formed on a metal plate, performs gold plating or nickel plating after gold plating, and then further copper plating and patterned Mffik.
After forming a prepreg on the copper oxide treated surface of the patterned steel foil and applying heat and pressure to form a laminate, drilling a hole in the laminate and copper plating the inner wall of the hole, further After forming resist) k, solder plating,
This is a method for manufacturing a recording electrode plate, which includes a step of etching after removing the resist.

An embodiment of the present invention will be described and explained in more detail with reference to the drawings.

In order to eliminate the dents and scratches that are the drawbacks of copper-clad laminates, as shown in Figure 1, a copper plating layer 2 (with a thickness of e.g. 20 μm) r On the surface of the 0 copper plating layer 20 to be formed, a photosensitive resist film γ is laminated or a photosensitive resist pattern is formed in the form of a photosensitive resist, and then a purple resist layer is formed by drying. If the S density at the extreme portion of the 0 recording i1 in which three resist patterns are formed is low, the resist patterns may be formed by screen printing.

Next, gold plating with different etching conditions from the copper plating layer 2 or nickel plating after gold plating is performed to form a corrosion-resistant layer 4 (thickness: 1 μm, for example), and then a copper plating pattern 5 is formed.
These platings may be either electroplating or MS-less plating. The thickness is, for example, 60 μm.

After the resist pattern 5 is completely peeled off as shown in FIG. 4, a copper oxide film is formed on the surfaces of the copper plating pattern 5 and the copper plating layer 2 in order to improve the adhesive strength with the prepreg. For example, copper oxide film is made of sodium chlorite,
Next, as shown in Fig. 5, one stainless steel plate was mechanically peeled off, and the entire patterned copper foil 6 was formed, as shown in Fig. 6. The prepregs 7 and the inner circuit boards 8 are alternately stacked on the copper oxidized surface of the copper foil 6, and the copper foil 9 is placed on the opposite side of the patterned hook, and heated and pressed to form a laminate.

The prepreg 7 is made by impregnating glass cloth with thermosetting resin such as epoxy resin, polyester resin, etc.
Only those that have been cured to B stage can be used. Further, the inner layer circuit board may be one manufactured by a subtract method or a semi-additive method using a copper-clad laminate.

After drilling holes in the laminate with a drill or the like, conductive holes r are formed using electroless steel plating or electroless copper plating and electric steel plating.

Next, a resist l''r is formed in the hole, in the pad area, and in the area other than the required surface pattern by the same method as the resist pattern 6 in FIG. 2, and after solder plating, the resist l''r is peeled off.

Then, in order to etch the copper and copper oxide (Cub) films without corroding the solder plating layer 16, etching is performed in a water bath of chromic acid and sulfuric acid.

In addition, when etching the solder plated etch resist using the subtract method, an etching solution containing an ammonium ion basin or an etching solution containing a supersulfur salt is usually used, or these etching solutions have an extremely high etching speed for copper oxide. It is unfavorable in terms of work efficiency because it has the disadvantage of being slow.

When the copper foil serving as the base is etched away by the above-described etching, the circuit formed in advance is exposed in the form of being embedded in the substrate.

Also, since the etching stops at the gold-plated layer, there is no risk of pattern breakage due to over-etching. I have it.

FIG. 7 shows a cross-sectional view of the recording electrode plate thus obtained, in which 10 is a through-hole plating, 11 is an inner layer circuit, and 12 is a copper foil 9? The base circuits 4 and 5 are preformed circuits, and 2 is the fc copper plate that remains unetched.

(Effects of the Invention) The following effects can be achieved in the method of manufacturing a recording electrode plate of the present invention.

(1) By forming a pattern on a copper-plated surface with no dents or scratches on the surface, the line width and line spacing are each 70 mm.
Fine patterns of micrometers or less can be easily obtained. Therefore, a highly line-contained recording electrode part of 8 lines/mm to 16 lines/film can be manufactured at a high yield.

(2) Since the circuit sound is formed by plating, the cross-sectional area (dots) of the circuit is larger than that of the subtract method, and the printing density is higher.

(3) Since a fine recording electrode portion is formed in advance and then laminated, inspection can be performed before lamination, improving yield.

(4) The conductor formed by copper plating is embedded in the resin and protected by the gold plating layer, so there is no disconnection due to overetching, and there is no side etching, so the line width accuracy is extremely high.

[Brief explanation of the drawing]

1 to 7 are cross-sectional views showing the manufacturing method of the present invention. 〇 Explanation of symbols 1 Stainless steel plate 2 Copper plating layer 3 Resist pattern 4 Gold plating layer 5 Patterned copper plating 6 Patterned copper foil 7 Prepreg 8 Inner layer circuit board 9 Copper rI310 Through-hole plating 11 Inner layer circuit 12 Circuit based on copper M' 13 Solder plating layer 9- Figure 1 Figure 4 Continued from page 1 ■Int, CI,' Identification symbol Inside the office Reference number H05K
3/42 6679-5F ■Inventor Yutaka Kawashima 474 Konouchi, Shimodate City

Claims (1)

[Claims] 1. A purple resist is formed on the copper plating formed on the metal plate, and then gold plating or nickel plating is applied after gold plating.
After that, a step of forming a patterned copper foil on the copper plating, a step of laminating the entire prepreg on the copper oxide treated surface of the patterned copper foil, heating and pressurizing it to form a laminate, and a step of forming a laminate with the patterned copper foil. A method for producing a recording electrode plate V, which includes the steps of drilling a hole, copper plating the inner wall of the hole, forming a resist, solder plating, peeling off the resist, and etching.