JPS59155992A - Printing mask to stepwise substrate surface - 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 Field of the Invention The present invention relates to a mask for forming a printing layer in a predetermined pattern on a flat surface of a substrate having projections, that is, a mask for printing on a stepped substrate surface. .

Conventional configuration and its problems Forming a printed layer in a predetermined pattern shape on a substrate surface using a printing technique is as follows: 1. This printing method has been widely used in the electronics industry, and has traditionally been indispensable for the formation of conductor layers, resistance layers, solder layers, etc., and pattern formation of etching resists, plating resists, etc. It has been put into practice.By the way,
Formation of a pattern layer by a printing method is convenient if the substrate is a flat surface, but if the substrate has protrusions, it is quite troublesome to avoid the protrusions and form a pattern on a predetermined plane. In particular, if a printing layer is formed on the surface of a stepped substrate having large protrusions that exceed the thickness of the printing mask, the adhesion of the mask will be impaired and a desired pattern shape will not be obtained.Objective of the Invention The present invention The present invention provides a mask for printing on a stepped substrate surface, which can minimize interference caused by protrusions when forming a printing layer on a flat portion of a substrate having protrusions.

Structure of the Invention To summarize, the present invention provides printing on a stepped substrate surface having a structure in which a printing mask plate having a predetermined pattern of openings and recesses corresponding to steamed metal protrusions is pasted to a net-like body at the periphery. Since the projections of the substrate are covered by the depressions, the adhesion of the printing mask plate to the flat surface of the substrate is maintained sufficiently, and a desired pattern printing layer can be formed.

DESCRIPTION OF EMBODIMENTS FIGS. 1a and 1b are a plan view and a sectional view of a printing mask used in an embodiment of the present invention, of which figure b shows the correspondence with the stepped substrate surface. That is, in this printing mask, openings 2a, 2b, 2C having a predetermined pattern shape and openings 3 corresponding to the protrusions of the substrate are provided in a phosphor bronze printing mask plate 1 having a thickness of about 0.1 mm. This printing mask plate 1 is attached to a mesh material, for example, a 100 mesh stainless steel screen 4, using an adhesive 5 at the periphery. A flexible mask material 6 having a diameter larger than that of the opening 3 is attached to the upper surface side of the opening 3 with an adhesive T, and this part forms a recess covering the protrusion of the substrate. do. The flexible mask material 6 is, for example, a metal thin film such as aluminum foil or copper foil, or a polyester thin film. An extremely thin material with a thickness of about 15 μm is suitable. The flexible mask material 6 needs to be thin and sufficiently flexible so as not only to prevent the printing paste from leaking, but also to not interfere with the smooth operation of the squeegee. As a printing mask, a stainless steel screen 4 is fixed to an outer frame 8 and stretched to maintain an appropriate degree of tension, and it can be used by inserting it into an ordinary printing machine. FIG. 1b also shows an outline of forming a printing layer using this printing mask, and shows the printing mask plate 1.
By moving the paste agent 9 on the top by moving the squeegee 10, openings 2a are formed on a predetermined surface of the substrate 11.

Printed layer 12a corresponding to pattern shapes 2b and 2C.

12b and 12C are formed, respectively. In addition, in the printing process, the gap t between the printing mask plate 1 and the substrate 11, which is meant to facilitate substrate movement, becomes 1=0 due to the suppression when the squeegee 10 is in operation. When,
Although the protrusions 13 on the substrate 11 collide under the flexible mask material θ, the flexible mask material 6 naturally
It is designed to withstand sufficient pressure.

According to experience, when the protrusion 13 on the substrate 11 has a hemispherical shape with a diameter of 1.0 mm and a height of 1.0 m, the printing mask plate 1 is a phosphor bronze plate with a thickness of 0.2 mm. Town 13', 1
．． The mask material 6 was made of a polyester film with a thickness of 0.5 mil (12.7 μm). In addition, stainless steel screen 4 obtained good results in forming a printed layer of solder paste by using a 100-mesh plain weave screen.

FIG. 2 is a cross-sectional view of the base of the printing mask used in another example, and when the printing mask plate 1 is bonded to the reticulated stainless steel screen 4, the bonding surface is made flexible. This is done on the side opposite to the mask material 6. According to such a bonding method, it can be used even if the height of the protrusion is increased somewhat.

According to experience, the protrusion shape has a diameter of ○, 5Tran,
Even in the case of a hemispherical mask with a height of 1.3 mm, a printing mask plate 1 with a thickness of 0.3 nm is used, and the other conditions are the same as in the first embodiment shown above, and the printing mask plate 1 has a sufficient cylindrical shape. The fruit was obtained.

It goes without saying that if the projections on the substrate are relatively small, the depressions can be provided directly on the printing mask plate 1.

In addition to the effects of the invention, as described in detail in the examples, according to the present invention, when printing a predetermined pattern layer on a flat surface of a substrate having protrusions, it is possible to form a layer corresponding to the protrusions in the printing mask. Since a recess is provided at the position where the protrusion is located, and a place for the protrusion to escape, the interference with the printing process due to the presence of the protrusion becomes extremely slight and can be ignored in practice. Therefore, the present invention makes it possible, for example, to form a printed layer on another flat surface of the substrate even after the electronic component has been mounted on the substrate, without any hindrance due to the presence of the electronic component. It is truly useful in practical terms.

[Brief explanation of the drawing]

1A and 1B are a plan view and a sectional view of a printing mask used in an embodiment of the present invention, and FIG. 2 is a sectional view of a main part of a printing mask used in another embodiment. 1° printing mask plate, 2 a, , 2 b, 2
c - Opening, 3 - Opening corresponding to protrusion, 4 Stainless steel screen, 5, 7... Adhesive, 6... Flexible uE MA:X Ridding, 8 Outside, frame, 9... Paste agent, 10- Sugieji, 11 Board, 12a, 12b
. 12c...Printing layer, °13...Protrusion.

Claims (2)

[Claims] (1) A mask for printing on a step base material surface having a structure in which a printing mask plate having openings in a predetermined pattern and depressions corresponding to substrate protrusions is bonded to a net-like body at the periphery. (2) A mask for printing onto a stepped substrate surface as set forth in claim 1, wherein the depression is an opening.