JPH08118592A - Method for registering printing mask - Google Patents

Abstract

PURPOSE: To conduct the registering accurately in a short time, and thus reduce the fatigue of an operator by disporsing a transparent substrate having an opaque reference patterns formed between a light source within the printing stage and a screen mask, and positioning the substrate by shifting it to the place where the light of the light source does not leak on the mask, while bringing either one of the printing stage and mask near it. CONSTITUTION: Light emitted from a light source 12 passes through a substrate 13 and leaks on the upper surface thereof and, herein, light leaks only on the part having no reference patterns formed thereon. When the screen mask 17 is brought near it in substantial contact relation, light leaking on the upper surface of the substrate leaks on the upper surface of the screen mask 17 through the part of a mask 18 having no mask 19 formed thereon. When the reference patterns 18 of the substrate 13 and the part of the mask 18 having no mask 19 of the screen mask 17 are superimposed each other, light does not leaks to the upper surface of the screen mask. The relation between the screen mask and the substrate is fixed at the place where light does not leak on the upper surface. After the fixation of the substrate 13, printing is effected after replacing the substrate 13 for the substrate to be printed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print mask position adjustment (mask alignment) method for screen printing, and more particularly to a method for aligning a screen mask and a print stage.

[0002]

2. Description of the Related Art For forming electrodes of ceramic electronic parts,
It is often done using screen printing. The conductor paste is screen-printed on the surface of the ceramic substrate using a screen mask having a predetermined pattern, and then baked to form the conductor paste.

FIG. 2 shows a screen printing device (a).
Is a front view and (b) is a plan view of the printing stage. The substrate 23 to be printed is mounted on the printing stage 21, the positioning is performed by the fixing pin 25, the screen mask 27 is brought into proximity, and the conductor paste is printed through the screen mask 27,
A predetermined conductor pattern is formed.

At this time, the desired conductor pattern cannot be obtained unless the printed substrate 23 and the screen mask 27 are accurately aligned. In this case, there are a method of adjusting by changing the position of the printed board 23 and a method of changing by changing the position of the screen mask 27, but actually, a method of performing alignment while repeatedly performing test printing is adopted. ing.

[0005]

The method of performing the alignment by repeating the trial and error as described above is difficult to align at a time, and it takes time because the alignment can be finally repeated several times. It usually takes about a minute.

Further, since the accuracy of alignment and the like are determined by the operator, it is difficult for an operator who is not skilled in the work to perform accurate alignment.

The present invention provides a method for aligning a printing mask, which enables accurate alignment in a short time and does not require skill in operation.

[0008]

SUMMARY OF THE INVENTION According to the present invention, the above-mentioned problems are solved by confirming the coincidence of a print pattern and a screen mask by using light and fixing the position of the substrate and the screen mask to be printed at that position. Is the solution.

That is, in a printing mask alignment method for aligning a substrate placement position of a printing stage with a screen mask, a light source is placed in the printing stage and a transparent opaque reference pattern is formed between the light source and the screen mask. It is characterized by arranging the substrate and moving one of the printing stage and the screen mask close to each other so that the light from the light source does not leak above the screen mask and positioning the substrate to be printed at that position. is there.

[0010]

Since the positions of the substrate and the screen mask to be printed are confirmed at the position where the light leakage is eliminated, the alignment can be performed in a short time and no skill is required. further,
It is also possible to arrange a CCD camera and make adjustments while viewing the image, which can greatly improve workability.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front sectional view showing an embodiment of the present invention. A light source 12 such as a fluorescent tube is arranged inside the printing stage 11. This light source 12 is located on the lower surface of the portion on which the substrate to be printed is mounted. Screen mask 17
A mask 19 corresponding to a predetermined print pattern is formed on the screen 18.

A transparent substrate 13 made of glass or the like on which a reference pattern is formed is mounted on the portion on which the substrate to be printed is mounted. This reference pattern is formed of an opaque pattern so as not to transmit light. In addition, when the translucent resin plate 14 is arranged on the lower side of the substrate 13, that is, on the light source 12 side, the light is not dazzling when the alignment is visually checked, and the alignment is facilitated.

The light emitted from the light source 12 leaks through the substrate 13 to its upper surface. In this case, the light leaks only to the portion where the reference pattern is not formed. When the screen masks 17 are brought close to each other so that they are almost in contact with each other, the light leaked to the upper surface of the substrate is reflected by the mask 18 where the mask 19 is not formed.
Leaks to the upper surface of the screen mask 17 through. When the reference pattern of the substrate 13 and the portion of the mask 18 of the screen mask 17 where the mask 19 is not formed overlap, light does not leak to the upper surface of the screen mask.

The positional relationship between the screen mask and the substrate is fixed at the above-mentioned position where light does not leak to the upper surface of the screen mask. Adjust either the screen mask or the substrate position until that position is reached. After the position of the board 13 is fixed, the board 13 may be replaced with the board to be printed and the printing operation may be performed.

Instead of visually observing from the upper surface of the screen mask, an image pickup device such as a CCD camera may be arranged above the screen mask and the image thereof may be displayed on the display. In this case, it is possible to arbitrarily select the position of the display and confirm it while moving the screen mask or the printing stage, and it is possible to greatly improve the workability. Further, since the position of the camera is constant, more accurate positioning can be performed than in the case of visual observation.

The present invention is not limited to the above example, the reference pattern can be formed on a semitransparent substrate, and in that case, it is not necessary to use a semitransparent resin plate for avoiding glare. . Further, as the light source, not only a fluorescent lamp is used to adjust the printing position on a wide surface, but also another lamp or a light emitting device may be used. For example, a point light source is sufficient when performing alignment with only two spots. Further, it can be used even when a metal mask is used, such as when printing cream solder for soldering as a mask.

[0018]

According to the present invention, the screen mask and the printing stage (substrate) can be accurately aligned in a short time. In particular, since it is easy to detect the matched state, the positional accuracy is also greatly improved.

Further, it becomes possible to further improve the workability by using a TV camera or the like, which does not require the skill of the worker and has the effect of reducing the fatigue of the worker.

[Brief description of drawings]

FIG. 1 is a front sectional view showing an embodiment of the present invention.

FIG. 2A is a front view and FIG. 2B is a plan view of a conventional screen printing apparatus.

[Explanation of symbols]

 11: Printing stage 13: Substrate 17: Screen mask

Claims (5)

[Claims] 1. A method of aligning a screen mask with a substrate placement position of a printing stage, wherein a light source is placed in the printing stage, and an opaque reference pattern is formed between the light source and the screen mask. A printing mask characterized by arranging a substrate, moving one of a printing stage and a screen mask to a position where light from a light source does not leak above the screen mask, and positioning the substrate to be printed at that position. Alignment method. 2. The printing mask alignment method according to claim 1, wherein the substrate on which the reference pattern is formed is a glass plate. 3. The print mask alignment method according to claim 1, wherein the substrate on which the reference pattern is formed is a semitransparent resin plate. 4. The printing mask alignment method according to claim 1, wherein a semitransparent resin plate is arranged between the light source and the transparent substrate on which the reference pattern is formed. 5. The print mask alignment method according to claim 1, wherein a television camera is arranged above the screen mask, and one of the print stage and the screen mask is moved while observing the image.