JPS58223217A - Circuit board - 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 (1) Technical Field A: The invention relates to a wiring board, particularly a contact structure of a wiring board.

(2) Prior Art Conventionally, for example, in an electronic desk 1-calculator, the contact structure of a wiring board that is crimped and connected to the lead terminals of a component (for example, an LSI chip) is made of a plastic film as shown in Figure 1. etc. substrate 1-1-(Ae, C via /C adhesive 2
Laminate a metal foil 3 such as U, and screen print a conductive etching resist 4 on this foil (~
Alternatively, as shown in Fig. 2, the conductive coating 45 was formed by screen printing on the film substrate 11. The contact structure of the key contact was also formed in a similar manner.

(3) Problem 1 of the prior art - According to the contact structure as described above, when the lead terminal 7 of the chip component 6 and the contact electrode 4 are crimped and connected as shown in FIG. Since both are made of hard materials, sufficient crimp connections cannot be made, and it is therefore necessary to employ a structure in which the stones are held by a fixed holding member 9 via a cushioning material 8 as shown in the figure. As a result, there were drawbacks such as an increase in the number of parts and a marked deterioration in workability.

On the other hand, if a two-contact structure is adopted for the contact points of a computer, bounce or chattering occurs when keys are touched (~, and there are problems such as a significant lack of stability in key operation). There was a purpose of the invention tl-The purpose of the invention was to produce paste-like rubber-like bullets (<1
A conductive paste such as carbon powder and 1/l Noiler is dispersed in a substance to form a conductive paste gold having 'JlII7.
From this pace l-f/, at least the contact part fr shadow is formed, which is good for mounting the parts.
Provides a wiring board contact structure that reduces the number of keys, has excellent workability, and can perform stable key operations without bounce, chipping, or slipping phenomena even after a month of keystrokes, etc. It is something to do.

(5) Example 1 A method for producing a conductive paste with elasticity is shown below.

Example (1) - Solvent Type 7 Reconcomb or urethane rubber or other elastic material is treated with a solvent (
For example, a conductive filler such as graphite or metal powder is completely dispersed in this solvent to create a paste, and this paste is etched as shown in Figures 41 and 5. L'jisl, agent 10 and C or c1 conductive coating 11 'C2+-1, single-cut, all-screen printing, etc.'Nigration formation [2, hardened by heating for a predetermined period of time 7] be.

In order to have a characteristic of 15 to 20 microns at 11 and 2, it is selected.

But this thickness? -J: For example, the surface roughness of the lead terminal and copper foil of a U-shaped chip component is affected by the roughness IF, 1:.

Example 01) ・Type A type heat vulcanization without using solvent (for example, heat-vulcanized silicone rubber in the form of a paste) is dispersed with a conductive filler such as graphite or metal powder by stirring, and then Afterwards, it is screen printed, heated, and cured by a hexagonal reaction.

(Application example) (1) Crimp connection of lead terminals of parts In FIGS. 6 and 7, (1) shows before crimping connection, and (2) v-'' shows after crimping connection. In Figure Cζ, the same part as above (CJJ, ■-
It is indicated by the whole bow.

(11) Key Inochi's contact connection Figures 8 and 9
In the figure, 12 is an elastic material (for example, rubber) having a key contact 13, 14 is a spacer 5, (iii) combination type, as shown in FIGS. 10 and 11, an elastic conductive paste ) (10, II) and the known conductive paste (
By using 4, 5) in combination, the necessary parts (for example,
(contact points only), the former paste can be applied completely.

(ψ For lowering resistance and preventing migration 11- As shown in Fig. 12, conductive filler paste 15 that easily causes migration phenomena such as silver (Ag) paste.
by coating it with the paste 11 according to the invention. In addition, it is possible to reduce the resistance of the wiring part.

(1)) Effects As is clear from the explanation of (10), according to the present invention, good crimp connections of parts can be carried out efficiently with a small number of parts, and when used for key contacts, You can perform stable key operations without chattering.

[Brief explanation of the drawing]

FIGS. 1 and 2 are cross-sectional views showing the contact structure of a conventional wiring board, FIG. 3 is a cross-sectional view showing an example of use, and FIGS. 4 and 5 d: An example of the contact structure of the wiring board according to the present invention. FIG. 6.7 (l:J: sectional view showing each usage example, FIGS. 8 to 12 I) are sectional views showing other embodiments. 1: Substrate 10.II: Conductive paste agent with elasticity Patent attorney Aihiko Fukushi (and 2 others) Figure 1 5 / Figure 3 Figure 5 Figure 2 Figure 4 / Figure 6 ρ // Figure 8 / Figure 10 / Figure 7 / 2 Figure 9 1 / Figure 72

Claims (1)

[Claims] Conductive filler such as carbon powder is dispersed in an elastic material such as paste) to form a conductive paste having a 54i paste (7), which constitutes at least a contact portion from f/U]. A wiring board characterized by: