JP2011245798A - Squeegee for screen printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a squeegee for screen printing whose apical surface has high straightness and be excellent in printing characteristic.SOLUTION: The squeegee for screen printing includes a plate-like squeegee body of an elastic resin and a metallic support for holding the squeegee body. A collar penetrating the squeegee body in the thickness direction is placed in the part held by the support of the squeegee body. The squeegee body is held with the support by way of the collar receiving a pressure from the support.

Description

The present invention relates to a screen printing squeegee.

In recent years, in the electronics field, a printing method has attracted attention as a manufacturing technique from the viewpoint of productivity and low environmental load, and a screen printing technique, which is one of the printing methods, has been incorporated into the manufacturing process.
For example, in the manufacturing process of a multilayer capacitor in which conductor layers and dielectric layers are alternately laminated, several tens to hundreds of times of multilayer printing are performed by screen printing with a printing film thickness of several μm. Dozens to hundreds of multilayer capacitors are manufactured simultaneously.
Therefore, in order to stabilize the product quality and improve the yield, it is important to stabilize the printing film thickness.
In the screen printing, in order to achieve stabilization (uniformization) of the printing film thickness, the printing pressure in the longitudinal direction of the screen printing squeegee and every time the squeegee is changed (the contact portion with the screen). It is important that the contact angle with respect to the screen is constant (uniform).

Conventionally, as a screen printing squeegee, a screen printing squeegee in which one end of a plate-like squeegee body made of polyurethane elastomer is sandwiched between metal supports and the squeegee body is fixed to the support by bolting has been proposed ( For example, see Patent Document 1).
When screen printing is performed using such a screen printing squeegee, if the printing film thickness is controlled by several μm, the printing film thickness is not constant over the entire printing surface, and the film thickness varies from printing area to printing area. May occur.

JP 2000-272090 A

Regarding the occurrence of such variations in printed film thickness, it was expected that the printing pressure of the screen printing squeegee and the contact angle with the screen were not uniform, but the root cause was not clear.
Therefore, as a result of repeated research by the present inventors, the cause of the uneven printing pressure and contact angle is that when the squeegee body is fixed to the support by bolting, the tightening part and the other parts Since the tightening pressure applied to the squeegee body is different, the degree of deformation of the squeegee body varies from part to part, and the tip surface of the squeegee body is deformed so that it undulates, resulting in a decrease in straightness of the tip surface. It became clear that there was something to end.
Therefore, the present inventors have made extensive studies to solve this problem, and when gripping the squeegee body with the support, the squeegee body is difficult to deform, and the straightness of the tip surface is maintained. A screen printing squeegee that can perform screen printing with high printing accuracy (uniformity of printed film thickness) even when the printed film thickness is several μm was completed.

The screen printing squeegee of the present invention comprises a plate-like squeegee body made of an elastic resin, and a metal support that holds the squeegee body.
A collar penetrating the squeegee main body in the thickness direction is disposed in a portion gripped by the support body of the squeegee main body,
The squeegee body is gripped by the support when the collar receives pressure from the support.

The screen printing squeegee is provided with a plurality of the collars, and the difference between the maximum value and the minimum value of the distance from the main surface of the squeegee body at the end face of each color is the difference between the squeegee body and the squeegee body. It is desirable that it is 3.5% or less of the thickness.

In the screen printing squeegee, the end face of the collar is flush with the main surface of the squeegee body or protrudes from the main surface of the squeegee body by 2.5% or less of the thickness of the squeegee body. It is desirable to be in position.

In the screen printing squeegee, the color material is preferably a metal.
In addition, it is desirable that the collar has a through hole in the thickness direction and / or a recess in the end surface.

The screen printing squeegee is provided with a plurality of the colors, and it is desirable that two of the colors serve as a positioning reference for the support of the squeegee body.
The collar is preferably disposed on the squeegee body by integral molding.

In the squeegee for screen printing, the elastic resin is desirably a polyurethane elastomer, and the polyurethane elastomer is desirably a polyurethane elastomer having a polyester polyol as a polyol component.
The polyester polyol is preferably a mixture of 10 to 90% by weight of a polyester polyol composed of ethylene glycol, diethylene glycol and succinic acid and 90 to 10% by weight of a polyester polyol composed of neopentyl glycol, diethylene glycol and succinic acid.

Hereinafter, in the present specification, when simply expressed as “squeegee”, it means “screen squeegee” unless otherwise specified.

Since the squeegee of the present invention has the above-described configuration, when the squeegee body is gripped by the support body, the pressure (gripping force) from the support body is substantially received by the collar disposed on the squeegee body. In other words, the squeegee body is gripped by the support body in a state where substantially no pressure is applied to the elastic resin constituting the squeegee body (the elastic resin is not substantially pressed by the support body).
That is, in the squeegee of the present invention, the collar functions as a member (thickness maintaining member) that prevents the thickness of the squeegee body from being deformed.
Therefore, the squeegee body does not deform by fixing to the support body, or even if it is deformed, the degree of deformation is very small, and the straightness of the squeegee body tip surface (straightness in the width direction and straightness in the fall direction) Can be maintained in an excellent state.
By using the squeegee of the present invention, screen printing can be performed with high film thickness accuracy.
Hereinafter, in the present specification, when the straightness of the front end face is simply described, both the straightness in the width direction and the straightness in the fall direction are indicated.

In the present invention, the straightness in the width direction of the tip surface of the squeegee body (hereinafter, also simply referred to as the width direction straightness of the squeegee body) is set so that the tip surface of the squeegee body faces the horizontal direction. ), And a point about 1 mm from the edge on the tip surface is scanned with a roughness meter across the entire length in the width direction, and the difference between the maximum value and the minimum value of the measured displacement is calculated.
Also, the straightness of the tip surface of the squeegee body in the fall direction (also referred to simply as the straightness of the squeegee body in the fall direction) lays the squeegee (or squeegee body) sideways so that the tip surface of the squeegee body faces the vertical direction. It is determined by calculating a difference between the maximum value and the minimum value of the measured displacement by scanning a portion about 1 mm in the horizontal direction from the edge of the tip surface with a roughness meter over the entire length in the width direction.
In addition, when the shape of the squeegee body is not a plate shape (for example, in the case of a sword squeegee, etc.), it is necessary to slightly change the measurement points of the straightness in the width direction and the straightness in the fall direction. This will be described later.

(A) is a perspective view which shows typically an example of the squeegee for screen printing of this invention, (b) is AA sectional drawing of (a). FIG. 2 is an exploded perspective view of the screen printing squeegee shown in FIG. (A) is the elements on larger scale of Drawing 1 (b), and (b) and (c) are the enlarged figures of the same part as Drawing 3 (a) in the squeegee main part of other embodiments, respectively. (A) is a front view of the squeegee main body which comprises the squeegee for screen printing shown in FIG. 1, 2, (b) is a perspective view of the color shown to (a). (A) is a front view of the squeegee main body which arrange | positioned the color of another embodiment, (b) is a perspective view of the collar shown to (a). (A) is a front view of the squeegee main body which arrange | positioned the color of another embodiment, (b) is a perspective view of the collar shown to (a). (A) is a front view of the squeegee main body which arrange | positioned the color of another embodiment, (b) is a perspective view of the collar shown to (a). (A)-(d) is a side view which shows typically the shape of the front end surface vicinity of the squeegee main body which comprises the squeegee for screen printing of this invention, respectively. It is a side view which shows typically another embodiment of the squeegee for screen printing of this invention. It is sectional drawing for demonstrating the manufacturing method of the squeegee main body which comprises the squeegee for screen printing of this invention. (A), (b) is a side view for demonstrating the usage method of the screen printing squeegee of this invention. (A) is a side view which shows typically the squeegee manufactured in the comparative example 1, (b) is a front view of (a).

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1A is a perspective view schematically showing an example of a screen printing squeegee according to the present invention, FIG. 1B is a cross-sectional view taken along line AA in FIG. 1A, and FIG. It is a disassembled perspective view of the squeegee for screen printing shown to a).
In this specification, when explaining the shape of the squeegee, in FIG. 1A, the X-axis direction is the thickness (or thickness direction), the Y-axis direction is the width (or width direction), and the Z-axis direction. Is referred to as height (or height direction).

As shown in FIGS. 1 and 2, in the squeegee 10, a part of a plate-like squeegee main body 12 made of polyurethane elastomer is sandwiched between two aluminum support jigs 11 </ b> A and 11 </ b> B and inserted through the squeegee main body 12. The squeegee body 12 is gripped by the support 11 by tightening the two support jigs 11A and 11B with the bolt 15 and the nut 17.
Therefore, the support jigs 11A and 11B are provided with through holes (bolt holes) 16A and 16B for inserting bolts, and the squeegee body 12 is provided with a through hole 13 for arranging a collar. ing.

Four through holes 13 are formed in the squeegee body 12, and a ring-shaped collar 14 made of iron is disposed in each through hole, and a bolt is inserted into the collar 14. Has been. Therefore, the collar 14 has a through hole formed in the thickness direction.
Here, the thickness of the collar 14 (T ₂ in FIG. 2) is the same as the thickness of the squeegee body 12 (T _{1 in} FIG. 2), and each end surface of the collar 14 has a plate shape. The squeegee main body 12 is arranged so as to be flush with the main surface.
The inner diameter of the collar 14 is designed to be substantially the same as the outer diameter of the bolt 15, and the bolt 15 inserted through the collar 14 is configured not to be displaced in directions other than the thickness direction.

In such a squeegee 10, the collar 14 having the same thickness as the thickness of the squeegee body 12 is disposed on the squeegee body 12 so that the main surface of the squeegee body 12 and the end surface of the collar 14 are in the same plane. Since the rigidity of the iron collar is higher than the rigidity of the elastic resin (polyurethane elastomer) constituting the squeegee main body 12, when the squeegee main body 12 is gripped by the support 11, the pressure from the support 11 ( The gripping force) is substantially received by the collar 14 disposed on the squeegee body 12, and the polyurethane elastomer constituting the squeegee body 12 is substantially not pressed by the support body 11, and the squeegee body 12 is supported by the support body 11. 11 will be held.
Therefore, the thickness of the squeegee main body 12 is maintained before and after the squeegee main body 12 is gripped by the support body 11, and as a result, the distal end surface 12 a of the squeegee main body 12 by causing the support body 11 to grip the squeegee main body 12. Deformation (deflection) is prevented, and the straightness of the distal end surface 12a is maintained.
In the present invention, the front end surface of the squeegee main body is a side surface of the plate-like squeegee main body, which is a surface that faces the screen when in use.

Further, the inner diameter of the collar 14 is designed to be substantially the same as the outer diameter of the bolt 15, and the bolt 15 inserted through the collar 14 is configured not to be displaced in directions other than the thickness direction. A collar having a through-hole communicating with the through-holes 16A ₁ and 16B ₁ formed in the tools 11A and 11B (the leftmost collar in FIG. 4A) functions as a positioning reference in the width direction and the height direction. A collar (the rightmost color in FIG. 4A) having a through hole communicating with the through holes 16A ₄ and 16B ₄ formed in the gripping jigs 11A and 11B functions as a positioning reference in the height direction.

Further, regarding the gripping jigs 11A and 11B constituting the support 11, four gripping holes are formed in the gripping jigs 11A and 11B in order to allow the bolts 15 to pass therethrough.
In the gripping jig 11A, four through holes 16A (16A _{1 to} 16A ₄ ) are all formed at the same height and at substantially equal intervals. Here, the cross sections of the through holes 16A _{1 to} 16A ₃ are circular, and the cross section of the through hole 16A ₄ is an oval (rounded rectangle). The diameter of the through-holes 16A ₁ is a diameter substantially the same bolt 15, the bolt 15 when inserted through the bolt 15 is displaced no size in the width direction and the height direction, height of the through hole 16A ₄ The diameter in the direction is substantially the same as the diameter of the bolt 15, and the bolt 15 is not displaced in the height direction when the bolt 15 is inserted. On the other hand, the diameters of the through holes 16A ₂ and 16A ₃ are larger than the diameter of the bolt 15.

Thus, the gripping tool 11A, the through-holes 16A ₁ is, has a function as positioning holes in the height direction and the width direction to the support of the squeegee body 12 (positioning reference), a high through-holes 16A ₄ of It functions as a directional positioning hole (positioning reference).
The reason why the cross-sectional shape of the through hole 16A ₄ are oblong (rounded rectangle) is as follows.
The squeegee body 12 is manufactured, for example, by integrally molding the collar 14 so that the collar 14 is simultaneously incorporated into a predetermined position when molding the resin composition. In this manufacturing process, heat treatment is performed. When the heat treatment is performed, the dimensions of the squeegee main body 12 may slightly deviate from the design value. At this time, the arrangement position of the collar also deviates from the design value. There is.
In this case, even deviations arrangement position of the collar, the cross-sectional shape of the through hole 16A _4, in the functioning the width direction positioning hole height direction if in the oval cross section which does not function as a positioning hole, This is because it can function as a positioning hole and a bolt hole in the height direction.

Also, the four through holes 16B (16B _{1 to} 16B ₄ ) are all formed at the same height in the gripping jig 11B at substantially equal intervals. Its shape and role are the same as each of the opposing through holes 16A (16A _{1 to} 16A ₄ ) formed in the gripping member 11A.
When a plurality of through holes 16A and 16B are formed in the holding jigs 11A and 11B, the through holes do not necessarily have to be formed at the same height and at equal intervals, and the design of the squeegee holder to which the squeegee 10 is attached. It may be formed at an arbitrary position according to the above.
Further, the positions (numbers) and the number of through holes 13 and collars 14 in the squeegee body 12 are not particularly limited.

In the squeegee of the present invention, the straightness of the front end surface of the squeegee body is maintained before and after attachment to the support. Therefore, it is desirable that the straightness of the tip surface is good in a state before being attached to the support.
Therefore, in the squeegee of the present invention, the tip surface may be a surface formed by cutting so as to improve the straightness of the tip surface of the squeegee body. Although it is possible to polish the tip surface, the polishing may cause minute irregularities on the tip surface, leading to a decrease in straightness of the tip surface.
The straightness of the distal end surface of the squeegee body is preferably 0.10 mm or less, which is the difference between the maximum value and the minimum value of the displacement measured by the above method. This is because if it exceeds 0.10 mm, it is difficult to control the printed film thickness with a few μm.
More desirably, it is 0.07 mm or less.

Moreover, it is desirable that the cutting process be performed using a blade. This is because it is possible to reliably and easily form the tip surface having excellent straightness.
Moreover, it is desirable that the blade is a hard blade.
The above cutting process can be performed with a round blade. However, when a round blade is used, if a chip occurs in a part of the cutting edge, the machining accuracy is lowered. Therefore, the round blade itself must be replaced. The confirmation work and replacement work are complicated and uneconomical.
Moreover, when cutting using a cutter, it is desirable to perform this cutting using a so-called ultrasonic cutter that performs cutting while ultrasonically vibrating the cutter.
This is because, depending on the material and thickness of the squeegee body, it may be difficult to cut with a blade, but even in such a case, the ultrasonic cutter can be used for reliable cutting.

FIG. 3A is a partially enlarged view of FIG. 1B, and FIGS. 3B and 3C are enlarged views of the same portion as FIG. 3A in the squeegee body of another embodiment. .
In the squeegee 10 shown in FIGS. 1 and 2, the main surfaces A and A ′ of the plate-like squeegee main body 12 and the end face of the collar 14 disposed on the squeegee main body 12 are formed to be on the same plane. However, in the squeegee of the present invention, the collar does not necessarily have to be arranged so that the end surface thereof is flush with the main surface of the plate-like squeegee body, both of which hold the squeegee body with the support. In this case, it is sufficient that the collar is substantially in a positional relationship to receive pressure from the support. Therefore, for example, as shown in FIG. 3B, one end surface 114 a of the collar 114 may be flush with the main surface of the squeegee main body 12, and the other end surface 114 b may protrude from the main surface of the squeegee main body 112. 3C, both end surfaces 214a and 214b of the collar 214 may protrude from the main surface of the squeegee main body 212. In any case, the collar receives the pressure from the support substantially so that the squeegee main body is gripped by the support, and the elastic member constituting the squeegee main body is substantially pressed by the support. This is because deformation of the squeegee body can be reliably prevented.
In FIGS. 3B and 3C, 115 and 225 are bolts.

In some cases, the end face of the collar may be in a position recessed from the main surface of the squeegee body.
In this case, the elastic member constituting the squeegee main body also receives pressure from the support, but depending on the amount of depression of the collar, the effect of the present invention, that is, the effect of preventing the deformation of the tip surface of the squeegee main body. This is because it can be enjoyed.
Specifically, the amount of depression of the collar (the distance between the main surface of the squeegee body and the end face of the collar) is desirably 1% or less of the thickness of the squeegee body.
When the amount of depressions in the collar exceeds 1%, the pressure received by the elastic member from the support increases, so the degree of deformation of the elastic member constituting the squeegee main body is large, and the squeegee is attached before and after the squeegee main body is attached to the support. This is because it becomes difficult to maintain the straightness of the front end surface of the main body, and the printing characteristics may be greatly deteriorated.
Moreover, when the amount of depressions in the collar increases, the end face of the collar does not receive pressure from the support when the squeegee body is attached to the support.

In addition, as shown in FIGS. 3B and 3C, when the end surface of the collar protrudes from the main surface of the squeegee body, or as described above, the end surface of the collar is recessed from the main surface of the squeegee body. When in position, the distance between the end face of each collar and the main face of the squeegee body is preferably the same. However, when the effects of the present invention can be enjoyed, the distance between the end face of each collar and the main surface of the squeegee body may vary.
In this case, the difference between the maximum value and the minimum value of the distance from the one main surface of the squeegee body at the end face of each color is desirably 3.5% or less of the thickness of the squeegee body.
An increase in this value means that the variation in the position of the end face for each color increases, and if the variation increases, the printing characteristics tend to deteriorate.

Further, when the end surface of the collar protrudes from the main surface of the squeegee body, the end surface of the collar may be in a position protruding from the main surface of the squeegee body within a range of 2.5% or less of the thickness of the squeegee body. desirable.
This is because if this value exceeds 2.5%, the printing characteristics tend to deteriorate.
The reason why the printing characteristics are deteriorated is that when the protruding amount of the end face of the collar from the main surface of the squeegee main body increases, the surface between the main surface of the squeegee main body and the surface opposite to the main surface of the squeegee main body of the support body. It is presumed that the gap becomes larger, and the free end length of the squeegee body appears to be apparently longer than the design value when the squeegee is used.

Moreover, in the squeegee of the present invention, the shape of the collar disposed in the squeegee body is not limited to the shape shown in FIGS. 1 and 2, and for example, the shape shown in FIGS. Good.
4A is a front view of the squeegee body constituting the squeegee shown in FIGS. 1 and 2, and FIG. 4B is a perspective view of the collar shown in FIG.
FIGS. 5 to 7 are front views of the squeegee body in which the collar of another embodiment is disposed, and FIG. 5B is a perspective view of the collar shown in FIG.

The squeegee main body 22 shown in FIGS. 5A and 5B is provided with four collars 24a and 24b.
Here, the two collars 24a have the same shape as the collar 14 shown in FIG. 4, respectively, and two collars 24b are disposed at positions sandwiched between the two collars 24a. . Each of the collars 24b has a ring shape with an oval cross section (round rectangular shape), and is configured such that a bolt can be inserted through the collar 24b. Therefore, the collars 24a and 24b are each formed with a through hole in the thickness direction.
In the squeegee main body 22, the collar 24a can function as a positioning reference.

Three collars 34a and 34b are disposed on the squeegee main body 32 shown in FIGS.
Here, each of the two collars 34a has the same shape as the collar 14 shown in FIG. 4, and a collar 34b is disposed at a position between the two collars. Here, the collar 34b is a plate-like body having an oval cross section (rounded rectangular shape), and a recess 134b is formed on an end surface thereof. Since the collar 34b is a plate-like body, a bolt cannot be inserted into the collar 34b.
On the other hand, the collar 34a can function as a positioning reference.

The reason why the recesses 134b are formed in the collar 34b is as follows. As will be described later, the squeegee body can be manufactured by injecting an uncured resin composition into a mold whose color is supported at a predetermined position and then performing a curing process. This is because forming a recess in the collar is suitable for supporting the collar at a predetermined position in the mold.
In addition, the said recessed part does not necessarily need to be formed.

The squeegee main body 42 shown in FIGS. 7A and 7B has the same configuration as the squeegee main body 12 shown in FIGS. 4A and 4B except that the shape of the collar 44 is different.
The collar 44 has the same outer edge shape as that of the collar 14, but has a cylindrical shape in which no through-hole or recess is formed.
Even with the squeegee main body 42 having such a configuration, although the bolt cannot be inserted into the collar, the collar receives pressure from the support when the squeegee main body is gripped by the support. The effect of the invention, that is, the effect of preventing the deformation of the tip surface of the squeegee main body 42 can be enjoyed.
Further, the collar 44 shown in FIG. 7B may have a recess formed on its end face.
When the squeegee main body 42 is gripped by the support, for example, the squeegee main body 42 may be gripped by the support 71 configured as shown in FIG.

Thus, in the squeegee of the present invention, the shape of the collar disposed on the squeegee body is not particularly limited, and may be a ring shape as shown in FIGS. It may be a plate shape as shown, a cylindrical shape as shown in FIG. 7, or a mixture of these. Further, the cross-sectional shape (the shape in front view) is not limited to a circle or an oval (rounded rectangle), and may be any shape such as a rectangle, an ellipse, a polygon, or a shape similar to these.

4 to 6, the collar functions as a positioning hole (positioning reference). However, in the squeegee of the present invention, the collar does not necessarily have a function as a positioning hole. Good (see, for example, squeegee body 42 shown in FIG. 7). In this case, a positioning mark or the like may be separately formed at an arbitrary position of the squeegee body.

Further, in the squeegee described so far, the angle of the edge on the tip surface side of the squeegee body (the ridge line portion formed by the main surface and the tip surface in the plate-like squeegee body: the portion indicated by 12b in FIG. 1B). However, in the squeegee of the present invention, the shape of the edge on the front end surface side of the squeegee body is not limited to such a shape. For example, as shown in FIGS. It may be a simple shape.

FIGS. 8A to 8D are side views schematically showing the shape of the vicinity of the front end surface of the squeegee main body constituting the squeegee of the present invention.
The squeegee main body 102 shown in FIG. 8A has a shape in which R chamfering is applied to both edge portions on the tip end surface 102a side.
In addition, in the squeegee body of this embodiment, when measuring the straightness in the width direction, measure the 1 mm portion from the outermost portion of the flat portion (the portion not subjected to the R chamfering) of the tip surface, and fall down When measuring the straightness of the direction, a portion 1 mm from the portion closest to the tip surface is measured from the flat portion of the main surface (the portion not subjected to the R chamfering).

The squeegee main body 103 shown in FIG. 8B is a so-called sword squeegee having a shape machined into a pointed shape on the tip side.
In the squeegee body of this embodiment, when measuring the straightness in the width direction, measure the sharp part on the tip surface side, and when measuring the straightness in the tilt direction, from the sharp part on the tip surface side Measure the 1 mm part.

The squeegee main body 104 shown in FIG. 8C has a shape in which a C-chamfer is applied to one edge portion on the tip surface 104a side.
In the squeegee main body of this embodiment, when measuring the straightness in the width direction, the outermost portion of the tip surface that is a flat portion (a portion that has not been subjected to C chamfering) and that has been subjected to C chamfering. When measuring the straightness of the falling direction, and measuring the straightness of the tilt direction, the tip of the flat part of the main surface on the C-chamfered side (the part that has not been chamfered) A 1 mm portion is measured from the surface side portion.

The squeegee main body 105 shown in FIG. 8D has a shape in which C-chamfering is performed on both edge portions on the tip end surface 105a side.
In the squeegee main body of the present embodiment, when measuring the straightness in the width direction, measure the 1 mm portion from the outermost portion of the flat portion (the portion where C chamfering is not performed) of the tip surface, and then fall down When measuring the straightness of the direction, a portion 1 mm from the portion closest to the front end surface is measured out of the flat portion of the main surface (the portion where C chamfering is not performed).

In order to make the shape of the squeegee main body on the front end surface side as shown in FIGS. 8A to 8D, when manufacturing the squeegee of the present invention by the method described later, the shape of the mold is changed to the squeegee main body. After the squeegee body having the shape shown in FIGS. 1 and 2 is manufactured in accordance with the shape of the front end surface, cutting or polishing may be performed on the front end surface side.
Any method may be selected, but for example, when a method of setting the shape of the mold to a predetermined shape is used, the molded squeegee body tends to be excellent in surface smoothness, and after the molding, cutting is performed. When a method of applying the above is selected, the straightness of the tip surface tends to be excellent.

In the squeegee described so far, the main surface of the squeegee is a flat surface. However, the shape of the squeegee body in the embodiment of the squeegee of the present invention may be, for example, as follows.
FIG. 9 is a side view schematically showing another embodiment of the squeegee of the present invention.
In the squeegee 40 shown in FIG. 9, the protrusions 142 a and 142 b are formed over the entire width direction of the front end portions (portions closest to the front end surface of the squeegee main body 42) of the gripping jigs 41 A and 41 B constituting the support body 41. Is formed. On the other hand, the squeegee main body 42 is formed with groove portions 42c at positions corresponding to the protrusions 142a and 142b over the entire width direction. In the squeegee 40, the protrusions 142a and 142b are fitted in the groove 42c.
In such a squeegee 40, the positional deviation in the height direction is less likely to occur.

Next, the material of the structural member which comprises the squeegee of this invention is demonstrated.
The material of the squeegee body is not particularly limited as long as it is an elastic resin, and examples thereof include polyurethane elastomer, silicone rubber, ethylene-propylene rubber, chloroprene rubber, butadiene rubber and the like.
Among these, polyurethane elastomers are desirable from the viewpoint of excellent mechanical strength and abrasion resistance.
In addition, as the polyurethane elastomer, a urethane prepolymer, which is a reaction product of a polyol component and an isocyanate component composed of polyester polyol or polyether polyol, cured with a curing agent can be used. From the viewpoint of superiority, it is desirable to use a polyester polyol as the polyol component.

As said polyester polyol, what dehydrated and condensed dicarboxylic acid and the glycol component can be used.
Examples of the dicarboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid and the like. These may be used alone or in combination of two or more.
Among these, it is desirable to use succinic acid. This is because the physical properties of the squeegee body, particularly the solvent resistance, are excellent.

Examples of the glycol component include ethylene glycol, diethylene glycol, 1,4-butanediol, trimethylolpropane, neopentyl glycol, and the like. These may be used alone or in combination of two or more.
Moreover, what is necessary is just to make the said dicarboxylic acid and the said glycol component react at 150-300 degreeC by molar ratio 1: 1-1: 3.

As the polyester polyol, in particular, a polyester polyol composed of ethylene glycol, diethylene glycol and succinic acid (hereinafter also referred to as polyester polyol A) 10 to 90% by weight, and a polyester polyol composed of neopentyl glycol, diethylene glycol and succinic acid (hereinafter referred to as “polyester polyol A”). A mixture of 90 to 10% by weight (also referred to as polyester polyol B) is desirable.

The mixture is more preferably a mixture of 20 to 80% by weight of the polyester polyol A component and 80 to 20% by weight of the polyester polyol B component.
It is because the organic solvent resistance of the polyurethane elastomer is extremely excellent by using such a mixture. The reason for this will be described below.

In the above polyester polyol A, the dicarboxylic acid is composed of succinic acid having a short chain length, and the glycol component is composed of diethylene glycol together with ethylene glycol having a short chain length. Therefore, the polyester polyol is composed of a methylene group of succinic acid and a methylene group of ethylene glycol. In addition to increasing the ester group density, the crystallinity is enhanced, and the ether group of diethylene glycol also enhances the crystallinity of the polyester polyol. Thus, the polyester polyol A has both high polarity and crystallinity, and gives a very high resistance to organic solvents to the resulting polyurethane elastomer.

On the other hand, the polyester polyol B has a neopentyl glycol component having a side chain methyl group symmetrically in the molecule instead of the ethylene glycol component in the polyester polyol A. However, since this neopentyl glycol has a relatively short chain length, the ester group density of the polyester polyol, and thus gives the polyester polyol B substantially the same polarity as the polyester polyol A. This lowers the crystallinity of the polyester polyol B and imparts hydrophobicity to the polyester polyol B.

As described above, the polyester polyol A having both high polarity and crystallinity has almost the same polarity, but by using the polyester polyol B having slightly low crystallinity, the crystallinity is maintained while maintaining the polarity as the polyester polyol component. While maintaining the organic solvent resistance of the resulting polyurethane elastomer, the compatibility with the polyisocyanate can be remarkably increased during the production.
Therefore, according to the above mixture, the polyester polyol and the polyisocyanate can be quickly and uniformly mixed, so that the polyurethane elastomer can be obtained by cast molding.

The isocyanate component is not particularly limited. For example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, a mixture thereof, 4,4′-diphenylmethane diisocyanate (MDI), carbodiimide-modified MDI, hydrogenated MDI And hexamethylene diisocyanate.

As the curing agent, a conventionally known curing agent can be used. Specific examples thereof include 1,4-butanediol, ethanediol, neopentyl glycol, diethylene glycol, bishydroxyethoxybenzene, hydroquinone-bis (2 -Hydroxyethyl) ether, 3,3′-dichloro 4,4′-diaminodiphenylmethane, bifunctional curing agents such as 4,4′-diaminodiphenylmethane, trimethylolpropane, glycerin, 1,2,6-hexanetriol , 1,2,4-butanetriol, trimethylolethane, 1,1,1-tris (hydroxyethoxymethyl) propane, diglycerin, pentaerythritol and other polyhydric alcohols, triethanolamine, triethanolamine, Isopropanolamine, diisopropa Amino polyhydric alcohols such Ruamin, and alkylene oxide at these polyfunctional compounds, e.g., ethylene oxide, propylene oxide, or amino polyhydric alcohols such as mixtures thereof comprising by ring-opening polymerization.
Among these, it is desirable to use a dihydric alcohol and a trihydric alcohol in combination. However, trihydric alcohol, when used excessively, lowers the resilience of the resulting elastomer, and is usually used in a range of 40 mol% or less based on the total amount of dihydric alcohol and trihydric alcohol. It is desirable. In particular, a combination of 1,4-butanediol and trimethylolpropane is preferable.

Further, these curing agents usually have a ratio of the isocyanate group, the polyester polyol, and the equivalent number of active hydrogens of the hydroxyl group or amino group of the curing agent to the polyisocyanate of 1.00 to 1.50. It is blended as follows.

The material of the collar disposed on the squeegee main body is not particularly limited as long as it is a hard material, and metal materials such as iron, aluminum, stainless steel, copper, phosphor bronze and other copper alloys, epoxy resin, POM (polyester). Hard resin such as oxymethylene).
Of these, iron is desirable. The reason is that since the coefficient of thermal expansion (linear expansion coefficient) is small, it is less likely to be deformed by integral molding, which will be described later, and because it is inexpensive, it is economically advantageous.

An adhesive layer may be formed on the outer peripheral surface of the collar. This is because the collar is surely fixed by the elastic resin constituting the squeegee body.
It does not specifically limit as said adhesive agent, The thing normally used for a metal can be used. As specific examples, for example, urethane-based, polyester-based, silane-based, polyamide-based, and phenol-based adhesives can be used.
Further, a silane coupling agent layer may be formed instead of the adhesive layer.

A roughened surface may be formed on the outer peripheral surface of the collar. This is because, by forming the roughened surface, the collar is surely fixed by the elastic resin constituting the squeegee body due to the anchor effect. The method for forming the roughened surface is not particularly limited, and examples thereof include etching treatment, plating treatment, polishing treatment, oxidation treatment, and grinding treatment by sandblasting.

In the squeegee main body constituting the squeegee of the present invention, it is desirable that the collar is securely fixed to the elastic resin constituting the squeegee main body.
If the collar is slidable, the grip in the thickness direction of the squeegee body will be insufficient, and the stability in the tilting direction will deteriorate during use.
I will explain this in more detail. When screen printing is performed, the squeegee is pressed against the screen at a predetermined displacement in a state where the squeegee is inclined at a predetermined angle (for example, an attachment angle of 75 °). Here, the deterioration in the stability in the falling direction means that the load applied to the squeegee body is not constant, and in this case, the printed film thickness varies.
If the collar is slidable as described above, the stability in the falling direction may deteriorate as the collar slides (the load applied to the squeegee body during printing may not be constant).

Examples of the material for the support include metals such as aluminum, iron, and SUS.
Of these, aluminum is desirable. The reason is that it is difficult to rust and has excellent machinability.

In the squeegee of the present invention, the size of the squeegee main body and the free end length are not particularly limited, and may be appropriately selected according to the design of the screen printing apparatus to be attached.
The general size is 5 to 20 mm in thickness, 30 to 90 mm in height, 100 to 300 mm in width, and about 10 to 30 mm in free end length. Of course, the size of the squeegee body according to the present invention is not limited to this size.

In the squeegee of the present invention, when the end face of the collar protrudes from the main surface of the squeegee main body (see FIGS. 3B and 3C), the end face of each color from the main surface of one of the squeegee main bodies. When the difference between the maximum value and the minimum value of the distance is not 0, that is, when the position of the end face of each color varies, the main surface on the side with a large protrusion amount or the main surface on the side with a large variation is not printed. It is desirable to attach the squeegee main body to the support so as to be the main surface on the side constituting the contact edge (112A in FIG. 11B).
When using the squeegee, when the squeegee is brought into contact with the screen, the squeegee receives pressure from the screen side. This pressure from the screen side is mainly applied to the portion where the main surface (112A ′ in FIG. 11B) opposite to the side constituting the contact edge is in contact with the support when the squeegee body is printed. It will be. For this reason, it is desirable for the main surface on the side opposite to the side that forms the contact edge when printing the squeegee body to have a smaller amount of projection and variation on the end face of the collar.For this reason, the orientation when the squeegee body is attached to the support is The above orientation is desirable.

Next, a method for manufacturing the squeegee of the present invention will be described.
FIG. 10 is a cross-sectional view for explaining a method for manufacturing a squeegee body constituting the squeegee of the present invention.
The squeegee of the present invention is manufactured, for example, by molding a squeegee main body with a collar disposed at a predetermined position, and then sandwiching the squeegee main body with a support body composed of two support jigs and fixing with a bolt. To do.

As shown in FIG. 10, the squeegee body is produced by supporting the squeegee 14 at a predetermined position in the molding space of the mold 18 and injecting the uncured resin composition 12 ′ into the mold 18 in this state. Then, the resin composition is cured.
Here, the mold 18 is formed with two protrusions 18a facing each other on the inner wall surface, and the collar 14 is formed into a molding space by inserting the protrusions 18a into the through holes provided in the collar 14. It can be supported at a predetermined position.

When the squeegee body is made of a polyurethane elastomer, a polyol component and an isocyanate component are reacted to form a prepolymer, and a prepolymer method in which the prepolymer is crosslinked and cured with a curing agent, or a polyol component, an isocyanate component, and a curing agent. A one-shot method can be employed in which they are mixed together and crosslinked and cured.
Here, when using a polyester polyol as the polyol component, it is desirable to employ the one-shot method, particularly when using a mixture of the polyester polyol A and the polyester polyol B. This is because the above-described polyester polyol has a relatively high viscosity.

The curing conditions at the time of the integral molding may be appropriately set according to the material of the squeegee main body. For example, when molding a polyurethane elastomer having a mixture of the polyester polyols A and B as a polyol component, 110 to 150 ° C. Then, it is desirable to cure in the mold for 20 to 120 minutes, and further to remove from the mold and post-cure at 100 to 120 ° C. for 3 to 24 hours.

Further, the squeegee main body may be formed, and after the squeegee main body is taken out of the mold, cutting may be performed to form the distal end surface of the squeegee main body.
The cutting process is as described above.

By using such a method, a squeegee body in which a collar is disposed at a predetermined position can be manufactured.
In addition, the method of manufacturing the squeegee body is not limited to such a method. For example, a squeegee is formed by molding a plate-like body made of an elastic resin having through holes and inserting a collar into the through holes after molding. The main body may be manufactured, or a squeegee main body is manufactured by forming a through hole in the molded body by machining such as drilling after creating a simple plate-shaped molded body and then inserting a collar into the through hole. May be.
And the squeegee of this invention can be manufactured by hold | gripping the squeegee main body produced by such a method with a support body.

Next, the usage method of the squeegee of this invention is demonstrated.
FIGS. 11A and 11B are side views for explaining a method of using the screen printing squeegee of the present invention.
11 (a) and 11 (b), the method of using the squeegee 10 shown in FIG. 1 will be described as an example.
The squeegee of the present invention is used by being fixed to a squeegee holder provided in a screen printing apparatus (not shown).
That is, as shown in FIG. 11A, the squeegee 10 is fixed to the squeegee holder 16 using the bolts 15 that fix the squeegee body 12 to the support 11.
And the squeegee of this invention is used by operating a screen printing apparatus in the state attached to the squeegee holder.
Specifically, as shown in FIG. 11B, in a state where the squeegee is inclined so as to have a predetermined squeegee mounting angle (an angle formed between the main surfaces 112A and 112A ′ of the squeegee main body 12 and the printing surface 51). Printing is performed by bringing the contact edge 112B of the squeegee main body 12 into contact with the screen 50 provided in the screen printing apparatus and moving the squeegee in the direction indicated by the arrow in the drawing. In this specification, in such a usage mode, the main surface 112A of the squeegee main body is also referred to as a surface constituting a contact edge at the time of printing, and the main surface 112A 'of the squeegee main body is in contact at the time of printing. It is also referred to as the main surface opposite to the side constituting the edge.

In the squeegee of the present invention, as described above, when the collar that functions as a positioning hole is provided in the squeegee body, the squeegee (squeegee body) is simply attached to the squeegee holder by the above method. It will be attached to a predetermined position with respect to the squeegee holder.

The printing conditions performed using the squeegee of the present invention are not particularly limited, but the squeegee mounting angle is 60 to 80 °, the gap (gap between the printing medium and the screen) is 0.5 to 2.5 mm, and the squeegee push-in amount is 0.1. It can be suitably used when printing is performed under conditions of ˜0.5 mm and squeegee printing pressure of 2 to 6 kg / cm.

As described above, in the squeegee of the present invention having the above-described configuration, when the squeegee main body is gripped by the support, the pressure from the support is substantially received by the collar disposed on the squeegee main body. The squeegee body is gripped by the support body in a state where substantially no pressure is applied to the elastic resin constituting the squeegee body (the elastic resin is not substantially pressed by the support body).
Therefore, the squeegee main body is not deformed by being fixed to the support body, and the straightness of the tip surface of the squeegee main body can be maintained.
By using the squeegee of the present invention, screen printing can be performed with high film thickness accuracy.

EXAMPLES Hereinafter, although an Example is hung up and demonstrated in more detail, this invention is not limited only to these Examples.

Example 1
In this example, the squeegee 10 having the shape shown in FIG. 1 was produced. The dimensional ratio is not the same as that of the squeegee 10.

Preparation of resin composition for squeegee body (1) An equimolar mixture of ethylene glycol (manufactured by Mitsubishi Chemical) and diethylene glycol (manufactured by Mitsubishi Chemical) and succinic acid (manufactured by Mitsui Chemicals) in the presence of a tetrabutyl titanate catalyst, The mixture was heated at 200 to 250 ° C. and reacted for 24 hours while dehydrating under reduced pressure to obtain a polyester polyol A having a terminal hydroxyl group and having a hydroxyl value of 57.7.

(2) Separately from the above (1), an equimolar mixture of diethylene glycol (Mitsubishi Chemical) and neopentyl glycol (Mitsubishi Gas Chemical) and succinic acid (Mitsui Chemicals) are present in the presence of a tetrabutyl titanate catalyst. Then, the mixture was heated at 200 to 250 ° C. and reacted for 24 hours while dehydrating under reduced pressure to obtain polyester polyol B having a terminal hydroxyl group and a hydroxyl value of 53.4.

(3) Next, 75 parts by weight (53.39 parts by weight) of the polyester polyol A and 25 parts by mole (18.24 parts by weight) of the polyester polyol B were mixed, heated to 100 ° C., and dried under reduced pressure with stirring. .
To the polyester polyol mixture thus obtained, 4.11 parts by weight of 1,4-butanediol (manufactured by Mitsubishi Chemical) and 0.56 parts by weight of trimethylolpropane (manufactured by Mitsubishi Gas Chemical) are added for 3 minutes. After premixing, 27.75 parts by weight of MDI (4,4'-diphenylmethane diisocyanate, isocyanate amount 29%, Mitsui Chemicals) modified with carboxylic diimide was added thereto, and an agitator SV manufactured by Shimazaki Seisakusho was used. The mixture was mixed at a rotational speed (450 rpm) until the mixture became uniform and transparent to obtain a resin composition for a squeegee body.

Molding of squeegee body An iron collar 14 having a thickness of 9.000 mm was prepared, and this collar was supported by a mold 18 having the shape shown in FIG. Thereafter, the resin composition for the squeegee body was poured into the mold 18 and cured at 110 ° C. for 1 hour, and then the molded body was removed from the mold and further post-cured at 110 ° C. for 12 hours to obtain a thickness of 9 A squeegee body 12 having a color of .000 mm × width 200.0 mm × height 45.0 mm was completed.
The collar 14 has a ring shape with an outer diameter of 6.0 mm, an inner diameter of 4.0 mm, and a thickness of 9.000 mm.
The collar mounting position (mounting center) is a position 15.0 mm from the upper end in the front view of the squeegee body 12 (FIG. 4), and is 40.0 mm, 80.0 mm, 120.0 mm and 160 in order from the left end. 4 locations at a position of 0 mm.

Squeegee manufacturing (mounting the squeegee body to the support)
As shown in FIGS. 1 and 2, the squeegee body 12 is sandwiched between the support jigs 11 </ b> A and 11 </ b> B, and the bolt 15 is tightened with a tightening torque of 1 Nm. .
The support 11 has a height from the front end surface of the squeegee body 12 to the upper surface of the support 11 (H ₁ in FIG. 1B) is 60.0 mm, and the free end length of the squeegee body 12 (FIG. 1). In (b), Lf) is designed to be 15.0 mm, and the thicknesses of the portions holding the squeegee bodies of the support jigs 11A and 11B are both 9.0 mm.

(Examples 2 and 3)
A squeegee was produced in the same manner as in Example 1 except that the bolt tightening torque was changed to 2 Nm (Example 2) and 5 Nm (Example 3), respectively.

Example 4
A squeegee was manufactured in the same manner as in Example 1 except that the collar thickness was 8.820 mm and the collars were disposed so that both ends thereof were recessed by 0.090 mm from the main surface of the squeegee body. .
Here, the arrangement position of the collar was adjusted by attaching a shim (inserting piece) to the inner wall surface of the mold. The method for adjusting the arrangement position of the collar is the same in other examples and comparative examples.

(Example 5)
A squeegee was manufactured in the same manner as in Example 1 except that the collar thickness was 9.090 mm and both ends thereof were each projected by 0.045 mm from the main surface of the squeegee body.

(Example 6)
A squeegee was manufactured in the same manner as in Example 1 except that the collar thickness was 9.270 mm and both ends thereof were each projected by 0.135 mm from the main surface of the squeegee body.

(Example 7)
A squeegee was manufactured in the same manner as in Example 1 except that the collar thickness was 9.450 mm and both ends thereof were each projected by 0.225 mm from the main surface of the squeegee body.

(Example 8)
A squeegee was manufactured in the same manner as in Example 1 except that the collar had a thickness of 9.540 mm and both ends thereof were each projected by 0.270 mm from the main surface of the squeegee body.

Example 9
A squeegee was produced in the same manner as in Example 1 except that a collar having a thickness of 9.040 to 9.050 mm was used. In the squeegee body produced in this example, the maximum value of the distance from the main surface of the squeegee body on the end face of the collar is 0.025 mm, and the minimum value is 0.020 mm. Therefore, the ratio of the difference between the maximum value and the minimum value of the distance from the main surface of the squeegee body on the end face of the collar to the thickness of the squeegee body is 0.06%.
In addition, the distance from the main surface of the squeegee body of the end face of the collar was measured by the following method.
That is, using a depth gauge (manufactured by Mitutoyo Corporation, Digimatic Micrometer DMC100-150M), a step (distance) between the collar end surface and the main surface of the squeegee body was measured. This measurement method is the same in other examples and comparative examples.
Further, the maximum and minimum values of the distance from the main surface of the squeegee main body of the end face of the color described in Table 1 are values on the surface side where the difference between the two becomes large. In this embodiment, the surface is printed. Sometimes the main surface opposite to the side constituting the contact edge was used. The same applies to Examples 10 to 13.

(Example 10)
A squeegee was produced in the same manner as in Example 1 except that a collar having a thickness of 9.040 to 9.140 mm was used. In the squeegee body manufactured in this example, the maximum value of the distance from the main surface of the squeegee body on the end face of the collar is 0.070 mm, and the minimum value is 0.020 mm. Therefore, the ratio of the difference between the maximum value and the minimum value of the distance from the main surface of the squeegee body on the end face of the collar to the thickness of the squeegee body is 0.56%.

(Example 11)
A squeegee was produced in the same manner as in Example 1 except that a color having a thickness of 9.040 to 9.320 mm was used. In the squeegee body manufactured in this example, the maximum value of the distance from the main surface of the squeegee body on the end face of the collar is 0.160 mm, and the minimum value is 0.020 mm. Therefore, the ratio of the difference between the maximum value and the minimum value of the distance from the main surface of the squeegee body on the end face of the collar to the thickness of the squeegee body is 1.56%.

(Example 12)
A squeegee was produced in the same manner as in Example 1 except that a collar having a thickness of 9.040 to 9.440 mm was used. In the squeegee body produced in this example, the maximum value of the distance from the main surface of the squeegee body on the end face of the collar is 0.220 mm, and the minimum value is 0.020 mm. Accordingly, the ratio of the difference between the maximum value and the minimum value of the distance from the main surface of the collar squeegee body to the thickness of the squeegee body is 2.22%.
(Example 13)
A squeegee was produced in the same manner as in Example 1 except that a collar having a thickness of 8.910 to 9.440 mm was used. In the squeegee body manufactured in this example, the maximum value of the distance from the main surface of the squeegee body on the end face of the collar is 0.220 mm, and the minimum value is −0.090 mm. Therefore, the ratio of the difference between the maximum value and the minimum value of the distance from the main surface of the squeegee body on the end face of the collar to the thickness of the squeegee body is 3.44%.

(Example 14)
The collar was disposed so that the thickness of the collar was 8.910 mm, one end surface was flush with the main surface of the squeegee body, and the other end surface was in a position recessed by 0.090 mm from the main surface of the squeegee body. A squeegee was produced in the same manner as in Example 1 except for the above.
In the present embodiment, the surface on which the end surface of the collar and the main surface of the squeegee main body are coplanar is the main surface on the side that forms the contact edge when the squeegee main body is printed.

(Example 15)
The collar is arranged to have a thickness of 9.045 mm, one end surface is flush with the main surface of the squeegee body, and the other end surface is at a position protruding from the main surface of the squeegee body by 0.045 mm. A squeegee was produced in the same manner as in Example 1 except for the above.
In the present embodiment, the surface on which the end surface of the collar and the main surface of the squeegee main body are coplanar is the main surface on the side that forms the contact edge when the squeegee main body is printed.

(Example 16)
The collar is disposed so that the thickness of the collar is 9.135 mm, one end surface is flush with the main surface of the squeegee body, and the other end surface protrudes from the main surface of the squeegee body by 0.135 mm. A squeegee was produced in the same manner as in Example 1 except for the above.
In the present embodiment, the surface on which the end surface of the collar and the main surface of the squeegee main body are coplanar is the main surface on the side that forms the contact edge when the squeegee main body is printed.

(Example 17)
The collar is disposed so that the thickness of the collar is 9.225 mm, one end surface is flush with the main surface of the squeegee body, and the other end surface is 0.225 mm protruding from the main surface of the squeegee body. A squeegee was produced in the same manner as in Example 1 except for the above.
In the present embodiment, the surface on which the end surface of the collar and the main surface of the squeegee main body are coplanar is the main surface on the side that forms the contact edge when the squeegee main body is printed.

(Example 18)
The collar is disposed so that the thickness of the collar is 9.270 mm, one end surface is flush with the main surface of the squeegee body, and the other end surface is in a position protruding 0.270 mm from the main surface of the squeegee body. A squeegee was produced in the same manner as in Example 1 except for the above.
In the present embodiment, the surface on which the end surface of the collar and the main surface of the squeegee main body are coplanar is the main surface on the side that forms the contact edge when the squeegee main body is printed.

(Example 19)
A squeegee was manufactured in the same manner as in Example 1 except that the thickness of the squeegee body and the thickness of the collar were both 6.000 mm and the shape of the support was changed accordingly.

(Example 20)
A squeegee was manufactured in the same manner as in Example 19 except that the collar thickness was 5.880 mm and the collars were disposed so that both ends thereof were recessed by 0.060 mm from the main surface of the squeegee body. .

(Example 21)
A squeegee was manufactured in the same manner as in Example 19 except that the collar had a thickness of 6.300 mm and both ends thereof were each projected by 0.150 mm from the main surface of the squeegee body.

(Example 22)
A squeegee was manufactured in the same manner as in Example 19 except that the collar thickness was 6.360 mm and both ends thereof were each projected from the main surface of the squeegee main body by 0.180 mm.

(Comparative Example 1)
In this comparative example, the squeegee 70 shown in FIG. 12 was produced.
FIG. 12A is a side view schematically showing the squeegee manufactured in Comparative Example 1, and FIG. 12B is a front view of FIG.
Molding of squeegee body As in Example 1, a squeegee having a thickness of 9.000 mm, a width of 200.0 mm and a height of 40.0 mm, in which a resin composition for a squeegee body is molded and no collar is provided. The main body 72 was completed.

Squeegee manufacturing (mounting the squeegee body to the support)
The squeegee main body 72 was sandwiched between the support jigs 71A and 71B, and the bolts 75 were tightened with a tightening torque of 1 Nm.
The shape of the support 71 is the same as that of the support 11 shown in FIGS. 1 and 2 except that the insertion position of the bolt 75 is different.
Further, the support 71 has a height from the front end surface of the squeegee main body 72 to the upper surface of the support 71 (H ₁ in FIG. 12A) is 60.0 mm, and the free end length of the squeegee main body 72 (FIG. 12). In (a), Lf) is designed to be 20.0 mm, and the thicknesses of the portions holding the squeegee main bodies of the support jigs 71A and 71B are both 9.0 mm.
The bolt mounting position is a position 10.0 mm from the upper end in the front view of the support 71 (FIG. 12B), and 40.0 mm, 80.0 mm, 120.0 mm and 160. There are four locations at 0 mm.

(Comparative Examples 2 to 4)
A squeegee was manufactured in the same manner as in Comparative Example 1 except that the bolt tightening torque was changed to 0 Nm (Comparative Example 2), 2 Nm (Comparative Example 3), and 5 Nm (Comparative Example 4), respectively.

(Comparative Example 5)
A squeegee was manufactured in the same manner as in Example 1 except that the collar thickness was 8.730 mm and the collars were arranged so that both end faces were recessed by 0.135 mm from the main surface of the squeegee body. did.

(Comparative Example 6)
The collar was disposed to have a thickness of 8.865 mm, one end surface being flush with the main surface of the squeegee body, and the other end surface being indented by 0.135 mm from the main surface of the squeegee body. A squeegee was produced in the same manner as in Example 1 except for the above.

(Comparative Example 7)
A squeegee was manufactured in the same manner as in Example 19 except that the collar thickness was 5.820 mm, and the collars were disposed so that both end surfaces thereof were recessed by 0.090 mm from the main surface of the squeegee body. did.

Evaluation of squeegee The squeegee manufactured in Examples and Comparative Examples was evaluated as follows.

(1) Press against the squeegee main body by the support The pressure-sensitive paper having a thickness of 0.2 mm between the support and the elastic resin part of the squeegee main body (manufactured by Fuji Film, prescale ultra-low pressure) And the color development of the pressure sensitive paper was observed to evaluate whether or not pressure was applied to the end face of the collar and the elastic resin portion of the squeegee body.
The results are shown in Tables 1 and 2.
(Evaluation criteria)
A: For each end portion of the pressure sensitive paper color corresponding to the squeegee body, each portion was uniformly colored, and the portion corresponding to the end surface of the color was darkly colored.
B: Only the part corresponding to the color end face of the pressure sensitive paper was colored.
C: Of the portions corresponding to the color end surfaces of the pressure-sensitive paper, only the portions corresponding to the end surfaces of some of the colors developed.
D: Only a part of the pressure-sensitive paper corresponding to the squeegee body (the part close to the tightening part) was colored.

(2) Straightness of the squeegee body in the width direction The straightness of the squeegee body in the width direction was evaluated using a surface roughness meter before and after the squeegee body was held by the support under the following conditions.
(Surface roughness meter and measurement conditions)
Surface roughness meter: Mitutoyo Surf Test SV-3100H8
Contact terminal (stylus) shape: 60 °, tip R2μm
Contact terminal pressing force: 0.75mN
Scanning speed: 10mm / s

Place the squeegee (or squeegee main body) still so that the tip surface of the squeegee body faces upward (or horizontally), and use the surface roughness meter to place a width of 1 mm from the edge of the tip surface. Scanned over the entire length in the direction. The difference between the maximum and minimum measured displacements was defined as the straightness in the width direction. The measurement points were set every 1 mm.
The results are shown in Tables 1 and 2.

(3) The degree of straightness of the tip surface of the squeegee body in the fall direction Straighten the squeegee (or squeegee body) sideways so that the tip surface of the squeegee body faces the vertical direction. Was used to scan a portion of 1 mm in the horizontal direction from the edge of the tip surface over the entire length in the width direction. The difference between the maximum value and the minimum value of the measured displacement was defined as the straightness of the falling direction. The measurement points were set every 1 mm. The measurement was performed before and after the squeegee body was gripped by the support.
The results are shown in Tables 1 and 2.

(4) Printing characteristics Screen printing was performed using the squeegees produced in the examples and comparative examples under the following conditions. The results are shown in Tables 1 and 2.
(Printing conditions)
Screen printing device (Ceria SSA-PC66φ manufactured by Tokai Shoji Co., Ltd.)
Screen frame: 300 x 300 mm (manufactured by Tokai Shoji)
Screen mesh: SUS # 400 (manufactured by Tokai Shoji)
Screen mesh opening: 120 x 120 mm
Ink: Nickel powder dispersion paste (Daiken Chemical Industry Co., Ltd.)
Substrate: OHP film (manufactured by Sumitomo 3M, OHP film CG341φ)
Squeegee mounting angle: 75 °
Gap (gap between substrate and screen): 1.3mm
Squeegee push-in: 0.1mm
Squeegee printing pressure: 4kg / cm

As is clear from the results shown in Tables 1 and 2, by arranging the collar on the squeegee body, the straightness of the squeegee body is less likely to decrease during bolt tightening when the squeegee body is attached to the support, and excellent printing is achieved. It has become clear that it has characteristics.
Further, from Examples 4-8 and 14-18 and Comparative Examples 5 and 6, the end face of the collar is in a position protruding from -1.0 to 2.5% of the thickness of the squeegee body from the main surface of the squeegee body. In some cases, it has been found to have very good printing properties.
Further, from Example 9-13, when there is variation in the protruding amount of the end face of the collar, the difference between the maximum value and the minimum value of the distance from the one main surface of the end face of each color is the squeegee body. It became clear that it was provided with extremely excellent printing characteristics when the thickness was 3.5% or less.

Although the results are not shown in Table 1, in each of Examples 9-18, the orientation of the squeegee body when the squeegee body was attached to the support was reversed (on the side constituting the contact edge during printing). When the printing characteristics were evaluated in the same manner (by exchanging the positions of the main surface and the opposite main surface), the printing characteristics were improved.

10, 20, 30, 40 Squeegee 11, 21, 31, 41 Support 12, 22, 32, 42, 102, 103, 104, 105 Squeegee body Lf Free end length

Claims (10)

A plate-shaped squeegee body made of an elastic resin, and a metal support that holds the squeegee body,
A collar penetrating the squeegee main body in the thickness direction is disposed on a portion of the squeegee main body gripped by the support,
A squeegee for screen printing, wherein the squeegee body is gripped by the support when the collar receives pressure from the support. A plurality of the collars are disposed;
2. The screen printing according to claim 1, wherein a difference between a maximum value and a minimum value of a distance from one main surface of the squeegee main body of each color end surface is 3.5% or less of a thickness of the squeegee main body. Squeegee. 2. The end face of the collar is flush with the main surface of the squeegee main body, or is in a position protruding from the main surface of the squeegee main body by 2.5% or less of the thickness of the squeegee main body. The squeegee for screen printing according to 2. The squeegee for screen printing according to any one of claims 1 to 3, wherein a material of the collar is a metal. The squeegee for screen printing according to any one of claims 1 to 4, wherein the collar has a through-hole formed in a thickness direction and / or a concave portion formed in an end surface. The screen printing squeegee according to any one of claims 1 to 5, wherein a plurality of the collars are arranged, and two of the collars serve as a positioning reference with respect to a support body of the squeegee body. The squeegee for screen printing according to claim 1, wherein the collar is disposed in the squeegee body by integral molding. The squeegee for screen printing according to any one of claims 1 to 7, wherein the elastic resin is a polyurethane elastomer. The squeegee for screen printing according to claim 8, wherein the polyurethane elastomer contains polyester polyol as a polyol component. 10. The polyester polyol according to claim 9, wherein the polyester polyol is a mixture of 10 to 90 wt% of a polyester polyol composed of ethylene glycol, diethylene glycol and succinic acid and 90 to 10 wt% of a polyester polyol composed of neopentyl glycol, diethylene glycol and succinic acid. Squeegee for screen printing.

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