JP2011000757A - Squeegee for screen printing and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a squeegee for screen printing comprising a resin-based squeegee having superior filling property and rolling property, without loosing the characteristics of metal squeegee, and causing no scratch on the surface of the metal mask surface.SOLUTION: The squeegee for screen printing includes: a thin plate-like squeegee body 2 consisting of a resin material with abrasion resistance and chemical resistance, both faces or one face thereof having a copper-clad part 3; and a lot of dimples 4 formed on at least one face of the copper-clad part 3 of the squeegee body, reaching the surface of the resin material.

Description

  The present invention relates to a screen printing squeegee and a method for manufacturing the same.

  Electronic circuit boards as printed wiring boards on which electronic circuit components are mounted are required to have high-density mounting of electronic components, and the demand is increasing year by year. In addition, as a solder paste printing technique for mounting electronic components on a printed wiring board, a technique for filling and transferring using a metal mask and a squeegee is generally established. As the squeegee for filling, a urethane squeegee and a metal squeegee are currently used. Metal squeegees are superior to urethane squeegees in terms of rolling and filling properties, but the metal mask surface may be scratched, so there are cases where it is unavoidable to use urethane squeegees. .

  Further, as a conventional technique, a screen printing squeegee is known in which a large number of fine recesses are formed on a running surface that entrains a solder paste of a squeegee body made of a thin metal plate having elasticity (see, for example, Patent Document 1). .

JP 2000-94637 A

  The conventional metal squeegee has a problem that the metal mask surface may be scratched. In addition, with the metal squeegee of the prior art, it is possible to apply an appropriate solder paste even to a narrow pitch component, but since it is made of metal, there is still a problem that the metal mask surface is scratched. The remaining and fine concave portions must be formed on the entire surface of the squeegee by chemical treatment, which is troublesome. Furthermore, the urethane and the resin material are swollen by the organic solvent contained in the solder paste, and swell deformation, warpage, and the like occur.

  The present invention has been made to solve the above-mentioned problems, from a resin-based squeegee that does not lose the characteristics of a metal squeegee that is excellent in rolling properties and filling properties and that is not easily scratched on the surface of the metal mask. A screen printing squeegee and a method for producing the same are provided.

  In the squeegee for screen printing according to the present invention, a thin plate-like squeegee body made of a wear-resistant and chemical-resistant resin material and having a copper-clad portion on both sides or one side thereof, and a copper-clad portion of the squeegee body And a plurality of dimples (dents) reaching the surface of the resin material.

  The resin material is formed on at least one surface of a thin plate-like squeegee body made of a wear-resistant and chemical-resistant resin material and having a copper-clad portion on both sides or one side, and a copper-clad portion of the squeegee body. The bottom surface of the squeegee body that contacts the metal mask is exposed with resin without a copper-clad portion.

  The thin plate-like squeegee body is a glass cloth base material polyimide resin multilayer printed wiring board material.

  A large number of dimples (dents) are dimple processed by an etching process.

  Moreover, the copper foil surface of the copper clad part is plated as a rust preventive treatment.

  Further, the thin plate-like squeegee body is provided with a water / oil repellent surface coating by a fluororesin treatment.

  In the method for manufacturing a screen printing squeegee according to the present invention, a thin plate-like squeegee body made of a wear-resistant and chemical-resistant resin material and having a copper-clad portion on both sides or one side thereof is prepared. As a rust-proofing process on the copper foil surface of the double-sided copper-clad portion of the squeegee body, and a step of forming a large number of dimples that reach the surface of the resin material by etching on at least one surface of the copper-clad portion of the squeegee body And a step of cutting the squeegee main body into a predetermined dimension and polishing the end face.

  In addition, a process for preparing a thin squeegee body made of a wear-resistant and chemical-resistant resin material and having a copper-clad portion on both sides or one side thereof, and etching on at least one surface of the copper-clad portion of the squeegee body Forming a plurality of dimples (dents) reaching the surface of the resin material by processing, forming a portion where the resin material is exposed by eliminating the copper-clad portion on the lower surface side that contacts the metal mask of the squeegee body, and a squeegee body And a step of plating the copper foil surface of the copper-clad portion as a rust preventive treatment, and a step of cutting the squeegee main body into a predetermined dimension and polishing the end surface.

  The squeegee body further includes a step of applying a water / oil repellent surface coating by fluororesin treatment.

  According to the present invention, there is an effect that it is possible to obtain a resin squeegee without losing the characteristics of the metal squeegee excellent in rolling property and filling property and without scratching the metal mask surface. This squeegee can suppress swelling and warping due to a sandwich structure with a metal (copper foil). Moreover, since it can manufacture with a commercially available cheap resin material, there exists an effect which can hold down cost low.

It is a side view which shows the use condition of the screen printing squeegee in Example 1 of this invention. It is a front view which partially enlarges and shows the structure of the screen printing squeegee in Example 1 of this invention. It is sectional drawing along the AA line of FIG. It is explanatory drawing for demonstrating the state of the flux between solder particles at the time of using the squeegee for screen printing in Example 1 of this invention. It is explanatory drawing for demonstrating the dimple processing effect of the screen printing squeegee in Example 1 of this invention. It is explanatory drawing for demonstrating the state of the flux between the solder particles at the time of using the conventional screen printing squeegee.

  A squeegee for screen printing 1 according to the present invention is a resin squeegee that reduces damage to a metal mask and has a print transfer property similar to that of a metal squeegee. Therefore, as a resin material, it is relatively inexpensive, particularly on the market, from the viewpoints of wear resistance, chemical resistance, ease of dimple processing, ease of end face polishing, ease of fluororesin coating, etc. A glass cloth base material polyimide resin multilayer printed wiring board material (glass polyimide multi GPY (for super multilayer) 2 is used as a squeegee body, and both sides are provided with copper-clad portions 3. This glass cloth base material polyimide The thickness of the resin multilayer printed wiring board material 2 is about 200 to 400 μm, and the thickness of the double-sided copper-clad portion 3 is about 10 to 20 μm. However, there is a difficulty in wear resistance, and there is a history that good results have not been obtained, and the double-sided copper-clad portion 3 of the glass cloth base material polyimide resin multilayer printed wiring board material 2 Then, dimple processing is performed by Cu etching treatment to generate a large number of dimples 4 that reach the surface of the resin material.The hole diameter of the dimples is about 0.22 mm, and the pitch is about 0. Although it is 0.5 mm, it can be arbitrarily changed depending on the size of the solder particles.In Fig. 2 and Fig. 3, only one surface of the double-sided copper-clad portion 3 is subjected to dimple processing to form a large number of dimples (dents) 4. Although the formed example is shown, it goes without saying that dimple processing may be performed on both sides to form a large number of dimples (dents) 4. Thereafter, as a rust prevention treatment on the copper foil surface of the double-sided copper-clad portion Apply Ni plating with a thickness of about 4μm, cut to a specified size with an NC machine, polish the end face with a flat grinder with a rough grindstone, and finally treat it with fluororesin in consideration of cleanability Water-repellent / oil-repellent surface coating is applied, and the lower surface side of the screen printing squeegee 1 in contact with the metal mask 5 is formed on the double-sided copper-clad portion 3 of the glass cloth-based polyimide resin multilayer printed wiring board material 2. When the Cu etching process is performed, the double-sided copper-clad portion is eliminated so that the glass cloth base polyimide resin is exposed to the surface, and the protruding amount of the exposed resin is about 2 mm. The obtained screen printing squeegee 1 is obtained by a resin squeegee that does not lose the characteristics of the metal squeegee excellent in filling property and rolling property and that does not scratch the surface of the metal mask 5.

Next, the state of the flux between the solder particles when the screen printing squeegee of the present invention is used will be described with reference to FIGS. 4 to 6 in comparison with a conventional screen printing squeegee. First, when the screen printing squeegee of the present invention is used, the state of the flux 6 between the solder particles is as follows. As shown in FIG. 4, the solder particles are uneven surfaces on the squeegee surface. The surface of the copper-clad portion 3) is subjected to resistance and moves in different directions and speeds, so that the solification (softening) of the flux 6 between particles is promoted and it is presumed to have fluidity. In addition, in FIG. 4, what is represented by the elongate triangle has shown that solification progresses and it has fluidity | liquidity. Further, as shown in FIG. 5, the dimple effect of the screen printing squeegee of the present invention is due to the fact that the thixotropy of the flux 6 between the particles is brought out by the movement direction and speed of the solder particles A and B being different. It is estimated to be.
On the other hand, the state of the flux 6 between the solder particles when the conventional screen printing squeegee 7 is used, as shown in FIG. 6, each solder particle and the flux 6 are moving at the same speed. Since it does not actively contribute to the promotion of solification and maintains the gel state, it is presumed that the fluidity is poor. In FIG. 6, a long and narrow triangle close to the conventional squeegee 7 indicates that the sol formation progresses and has fluidity, but the amount thereof is extremely small. As shown by a short triangle, most of them are presumed that most of them maintain the gel state and have poor fluidity, as indicated by a short triangle.

  In Example 1 described above, the double-sided copper-clad glass cloth substrate polyimide resin multilayer printed wiring board material was used, but the double-sided copper-clad glass cloth base polyimide resin multilayer printed wiring board is not necessary. Needless to say, similar effects can be obtained even if the material is used.

  In Example 1 described above, the lower surface side of the screen printing squeegee 1 that is in contact with the metal mask 5 is formed on both sides when Cu etching is applied to the double-sided copper-clad portion 3 of the glass cloth base material polyimide resin multilayer printed wiring board material 2. The glass-clad base polyimide resin was exposed to the surface without the copper-clad portion, but in this Example 3, the lower surface side in contact with the metal mask 5 of the screen printing squeegee 1 is the glass cloth base polyimide. When performing Cu etching on the double-sided copper-clad part 3 of the resin multilayer printed wiring board material 2, the single-sided copper-clad part is masked to leave the single-sided copper-clad part, and the glass cloth base polyimide resin is exposed on the opposite side. The part which performs is provided. In this case, the portion where the glass cloth base polyimide resin on one side of the opposite side is exposed comes into contact with the metal mask 5, but the portion where the single-sided copper-clad portion that does not come into contact with the metal mask 5 remains contributes to improving the strength of the squeegee. There is an effect.

1 Screen printing squeegee 2 Glass cloth substrate polyimide resin multilayer printed wiring board material (resin-based material)
3 Double-sided copper-clad part 4 Dimple (dent)
5 Metal mask 6 Flux 7 Conventional squeegee

Claims (9)

A thin squeegee body made of a wear-resistant, chemical-resistant resin material, with a copper-clad portion on both sides or one side,
A plurality of dimples (dents) formed on at least one surface of the copper-clad portion of the squeegee body and reaching the surface of the resin material;
A squeegee for screen printing, comprising: A thin squeegee body made of a wear-resistant, chemical-resistant resin material, with a copper-clad portion on both sides or one side,
A plurality of dimples (dents) formed on at least one surface of the copper-clad portion of the squeegee body and reaching the surface of the resin material;
The screen printing squeegee is characterized in that a resin having no copper-clad portion is exposed on a lower surface side of the squeegee main body that contacts the metal mask.   The squeegee for screen printing according to claim 1 or 2, wherein the thin plate-like squeegee body is a glass cloth base material polyimide resin multilayer printed wiring board material.   The squeegee for screen printing according to any one of claims 1 to 3, wherein a large number of dimples (dents) are dimple processed by an etching process.   The squeegee for screen printing according to claim 4, wherein the copper foil surface of the copper-clad portion is plated as a rust preventive treatment.   6. The squeegee for screen printing according to claim 5, wherein the thin plate-like squeegee body is provided with a water / oil repellent surface coating by a fluororesin treatment. A process of preparing a thin plate-like squeegee body made of a wear-resistant, chemical-resistant resin material and having a copper-clad portion on both sides or one side thereof;
Forming a large number of dimples (dents) reaching the surface of the resin material by etching on at least one surface of the copper-clad portion of the squeegee body;
Applying plating as a rust-proofing treatment to the copper foil surface of the copper-clad portion of the squeegee body,
Cutting the squeegee body into a predetermined dimension and polishing its end face;
A method for producing a screen printing squeegee, comprising: A process of preparing a thin plate-like squeegee body made of a wear-resistant, chemical-resistant resin material and having a copper-clad portion on both sides or one side thereof;
A resin is formed by forming a large number of dimples (dents) reaching the surface of the resin material by etching on at least one surface of the copper-clad portion of the squeegee body, and eliminating the copper-clad portion on the lower surface side in contact with the metal mask of the squeegee body Forming a portion where the material is exposed;
Applying plating as a rust-proofing treatment to the copper foil surface of the copper-clad portion of the squeegee body,
Cutting the squeegee body into a predetermined dimension and polishing its end face;
A method for producing a screen printing squeegee, comprising:   8. The method for producing a squeegee for screen printing according to claim 7, further comprising a step of applying a water- and oil-repellent surface coating to the squeegee body by a fluororesin treatment.

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