JPH0226741A - Squeegee - Google Patents

Abstract

PURPOSE:To equalize film thickness to long-term service by burying a beltlike reinforcing plate in the longitudinal direction of approxi mately the central section of a urethane rubber. CONSTITUTION:A squeegee 1 is formed of a urethane rubber in thickness of 8-13mm. A beltlike reinforcing plate 2 in plate thickness of approximately 2-4mm is buried in the longitudinal direction of approximately the central section of the squeegee 1. Al, stainless, a steel plate, a rigid synthetic resin or a member, in which these materials are combined properly, is used as the material of the plate 2. Grooves 3 are shaped appropriately to the surface and rear of the beltlike reinforcing plate 2 in order to improve adhesion with the urethane rubber surrounding the outer circumference of the plate 2. An adequate groove such as a recessed groove 4, a dovetail groove 5, an oval groove 6, an irregular groove 7, etc., is adopted as the shape of the groove 3. Such a squeegee can be employed in the printing process of the manufacture of a printed wiring board.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a squeegee used in a screen printing process, which is a process for manufacturing printed wiring boards and the like.

Conventional technology Screen printing is basically carried out with the plate floating above the printing material, that is, with a certain distance between the screens. And the ink on the screen plate is
As the squeegee moves, it is stuffed into the holes in the gauze, and some of it slips under the gauze. After passing the squeegee, the gauze is separated from the printing material due to the tension of the gauze, since the gauze is spaced apart from the screen. At this time, due to the adhesive force of the ink, the ink remains on the printing medium side and printing is performed. The stage used in this process is made of NR, SBR, NBR, CR.
lI IR, silicone, fluorine, urethane rubber, etc., and one suitable for the ink to be used is selected as appropriate, but urethane rubber is usually used. Its hardness is generally in the Shore hardness range of 60 to 80 degrees. The shape for printing on flat surfaces is rectangular with a thickness of 6 to 9 cm, and for printing on curved surfaces, a sword shape with a pointed tip is often used. Furthermore, the tip of the squeegee must be well polished and sharp in order to cleanly wipe away the ink on the plate. This is because when the ink is curled up, more ink comes out and it tends to bleed. It is also important to choose a squeegee with high solvent resistance and abrasion resistance so that the hardness and shape do not change significantly during printing.

Problems that the invention aims to solve In recent years, the printing density of printed wiring boards has been promoted to be higher, but in particular, technology has been developed to sufficiently withstand electromagnetic wave countermeasures, noise countermeasures, and high frequency response. Needs are changing.

Gold, silver, copper,
Conductive paint pastes such as solder and carbon are used. In metal paste printing using these materials, the conventional squeegees made of urethane rubber or the like described above have weak resistance to printing pressure and cannot perform stable printing. However, in the case of this metal base, especially the resistance value,
It is necessary to manufacture stable products under strict standards such as voltage resistance, and the film thickness after printing is an important point, but conventional squeegees do not sufficiently cover the above points. I couldn't.

Means for Solving the Problems The present invention solves the above-mentioned drawbacks of conventionally used squeegees, and will be described in detail below with reference to the drawings.

1 is a squeegee of the present invention, which is made of horse tan rubber having a thickness of 8IIi1 to 13mm. A strip-shaped reinforcing plate 2 having a plate thickness of 211111 to 4 w is buried in the longitudinal direction of the substantially central part. The material used is aluminum, stainless steel, steel plate, hard synthetic resin, or a suitable combination thereof.

In order to improve adhesion to the urethane rubber surrounding the outer periphery of the strip-shaped reinforcing plate 2, appropriate grooves 3 are formed on its front and back surfaces. As shown in FIG. 3, suitable shapes such as a concave groove 4, a dovetail groove 5, an oval shape 6, an uneven groove 7, etc. are adopted as the shape of the 3-dimensional shape.

Effects of the Invention The squeegee of the present invention having the above structure can be used, for example, in the printing process of manufacturing printed wiring boards, and can be used for pattern printing such as negative patterns and positive patterns, resist printing such as solder masks and liquid cyst masks, and gold printing. It can be used for metal paste printing of silver, copper, solder, carbon, etc. Particularly in metal paste printing, products with high standards such as resistance value and voltage resistance are required, and therefore the film thickness after printing is important. Because of this, it is strong against printing pressure, and as a result, it has become possible to maintain a uniform film thickness for long periods of use. In addition, the occurrence of bleeding and blurring during printing was significantly reduced.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the squeegee of this invention, Fig. 2 is a perspective view of a band-shaped reinforcing plate used in this invention, and Figs.
d) is a side view showing the shape of the groove of the strip-shaped reinforcing plate;
The figure is a front view showing a state in which screen printing is performed using a squeegee. In the diagram ■... Squeegee 3... Groove 5... Dovetail groove 7... Uneven groove

Claims (3)

[Claims] (1) A squeegee characterized by having a strip-shaped reinforcing plate embedded in the longitudinal direction of the substantially central portion of urethane rubber. (2) The belt-shaped reinforcing plate is aluminum, stainless steel, steel plate,
The squeegee according to claim 1, which is selected from hard synthetic resins or appropriate combinations thereof. (3) The squeegee according to claims 1 and 2, characterized in that the thickness of the reinforcing strip is about 2 to 4 mm, and grooves for adhesion are formed on the front and back surfaces of the reinforcing plate.