阅读说明：本技术 丝网印刷用浆料挡条及其使用方法 (Paste barrier strip for screen printing and using method thereof ) 是由 奚琦鹏 潘琦 史卓群 杨立功 于 2020-12-31 设计创作，主要内容包括：本发明公开了一种丝网印刷用浆料挡条,包括一对竖置端面、平置底面以及斜置在底面正上方的浆料阻挡面；浆料阻挡面由一对斜面组成。在丝网印刷时使用本发明的浆料挡条,能使浆料分布得更均匀,可提高丝网印刷的工艺精度、均匀性和稳定性。(The invention discloses a slurry barrier strip for screen printing, which comprises a pair of vertically arranged end faces, a horizontally arranged bottom face and a slurry barrier face obliquely arranged right above the bottom face; the slurry blocking surface is comprised of a pair of inclined surfaces. When the slurry barrier strip is used in screen printing, the slurry can be distributed more uniformly, and the process precision, uniformity and stability of the screen printing can be improved.)

1. Paste blend stop for screen printing, its characterized in that, including strip main part, strip main part includes: the slurry blocking device comprises a pair of vertical end faces, a flat bottom face and a slurry blocking face, wherein the vertical end faces are respectively arranged at two ends of the strip-shaped main body in the length direction, the flat bottom face is positioned between the pair of end faces, and the slurry blocking face is positioned between the pair of end faces and is obliquely arranged right above the bottom face;

the slurry blocking surface consists of a pair of inclined surfaces which are arranged in a central symmetry mode in the length direction of the strip-shaped main body; the boundary line of the inclined planes is taken as a first boundary line which is vertical to the length direction of the strip-shaped main body, the first boundary line is obliquely arranged right above the bottom surface, and the bottom end of the first boundary line is connected with the bottom surface; the second boundary lines at the two ends of the strip-shaped main body in the length direction are symmetrically arranged at the center of the strip-shaped main body in the length direction; the second boundary line is obliquely arranged above the bottom surface, and the bottom end of the second boundary line is connected with the bottom surface; the third boundary line of the pair of inclined planes is symmetrically arranged by the first boundary line by taking the boundary line of the inclined planes and the bottom surface as the third boundary line;

the included angle between the first boundary line and the bottom surface is larger than that between the second boundary line and the bottom surface.

2. The paste dam for screen printing according to claim 1, wherein the angle between the first boundary line and the bottom surface is 45 to 60 degrees.

3. The paste dam for screen printing according to claim 1, wherein the angle between the second boundary line and the bottom surface is 20 to 45 degrees.

4. A paste dam for screen printing according to claim 1, wherein the third boundary lines of said pair of inclined surfaces are located on the same straight line.

5. A paste dam for screen printing according to claim 1, wherein said pair of end faces are provided symmetrically with respect to the center in the longitudinal direction of the strip-like body.

6. A paste dam for screen printing according to claim 1, wherein said pair of end faces are perpendicular to the longitudinal direction of the strip-like body.

7. The method of using a paste dam for screen printing according to any one of claims 1 to 6, wherein the paste dam is used in screen printing, comprising the steps of:

and taking the position of the screen plate where the printing of the forward stroke or the reverse stroke of the scraper is finished as a cutter collecting position, horizontally placing the slurry barrier strip on the screen plate, enabling the length direction of the slurry barrier strip to be vertical to the stroke direction of the scraper, and arranging the slurry barrier strip outside the cutter collecting position, wherein the slurry barrier strip is close to the cutter collecting position.

8. The use method of the paste barrier strip for screen printing according to claim 7, wherein the distance between the paste barrier strip and the knife-retracting position is controlled to be 0.5 to 1.5 cm.

9. The method of using a paste bar for screen printing according to claim 7, wherein a pair of end faces of the paste bar are respectively abutted against inner edges of the frames of the screens.

Technical Field

The invention relates to the technical field of screen printing, in particular to a slurry barrier strip for screen printing and a using method thereof.

Background

The screen printing machine mainly comprises: a printing head (comprising a scraper and an ink return knife), a printing table surface, a net frame and the like. The screen printing plate is fixed on the screen frame, the scraper extrudes the screen printing plate to deform, the slurry on the screen printing plate is extruded to form a pattern, and the slurry scraped by the scraper is scraped back to the initial position by the ink returning knife, so that the printing process is completed once.

As shown in fig. 1, in the case of long-time multi-batch printing, due to the deformation of the scraper to the screen, the screen has a height difference between the middle part and the two sides, and the slurry has fluidity, and after long-time operation, the slurry can slowly flow from the high position to the low position, so that the more the slurry in the middle part of the screen gathers, the less the slurry in the two sides of the screen, the more the slurry in the middle part of the screen after ink return, and the less the slurry in the two sides of the screen, when the scraper pushes forward again, the more the slurry in the middle part of the screen is squeezed, and the relatively less the slurry in the two sides of the screen is squeezed, which affects the printing uniformity.

Taking a screen printing technology in the photovoltaic industry as an example, the screen printing technology in the photovoltaic industry has high requirements on printing precision, uniformity and continuity, if a metal electrode is printed, the current collection is influenced by the non-uniform slurry, if the printed doped slurry is printed, the non-uniform printing can cause the non-uniform doping sheet resistance, and the junction depth and the concentration difference of different areas are large.

Disclosure of Invention

The invention aims to provide a slurry barrier strip for screen printing and a using method thereof.

In order to achieve the above object, the present invention provides a paste barrier strip for screen printing, comprising a strip-shaped main body, the strip-shaped main body comprising: the slurry blocking device comprises a pair of vertical end faces, a flat bottom face and a slurry blocking face, wherein the vertical end faces are respectively arranged at two ends of the strip-shaped main body in the length direction, the flat bottom face is positioned between the pair of end faces, and the slurry blocking face is positioned between the pair of end faces and is obliquely arranged right above the bottom face;

the slurry blocking surface consists of a pair of inclined surfaces which are arranged in a central symmetry mode in the length direction of the strip-shaped main body; the boundary line of the inclined planes is taken as a first boundary line which is vertical to the length direction of the strip-shaped main body, the first boundary line is obliquely arranged right above the bottom surface, and the bottom end of the first boundary line is connected with the bottom surface; the second boundary lines at the two ends of the strip-shaped main body in the length direction are symmetrically arranged at the center of the strip-shaped main body in the length direction; the second boundary line is obliquely arranged above the bottom surface, and the bottom end of the second boundary line is connected with the bottom surface; the third boundary line of the pair of inclined planes is symmetrically arranged by the first boundary line by taking the boundary line of the inclined planes and the bottom surface as the third boundary line;

the included angle between the first boundary line and the bottom surface is larger than that between the second boundary line and the bottom surface.

Preferably, the included angle between the first boundary line and the bottom surface is 45-60 degrees.

Preferably, the included angle between the second boundary line and the bottom surface is 20-45 degrees.

Preferably, the third boundary lines of the pair of inclined surfaces are located on the same straight line.

Preferably, the pair of end faces are provided symmetrically with respect to the center of the longitudinal direction of the strip-shaped body.

Preferably, the pair of end faces are perpendicular to the longitudinal direction of the strip-shaped body.

The invention also provides a using method of the slurry barrier strip, which uses the slurry barrier strip in screen printing and comprises the following steps:

and taking the position of the screen plate where the printing of the forward stroke or the reverse stroke of the scraper is finished as a cutter collecting position, horizontally placing the slurry barrier strip on the screen plate, enabling the length direction of the slurry barrier strip to be vertical to the stroke direction of the scraper, and arranging the slurry barrier strip outside the cutter collecting position, wherein the slurry barrier strip is close to the cutter collecting position.

Preferably, the distance between the slurry barrier strip and the cutter collecting position is controlled to be 0.5-1.5 cm.

Preferably, a pair of end faces of the slurry barrier strip are respectively abutted against the inner edge of the screen frame of the screen printing plate.

The invention has the advantages and beneficial effects that: the invention provides a slurry barrier strip for screen printing and a using method thereof.

The invention adds a slurry barrier strip near the printing end position (the cutter collecting position) of the scraper, the slurry blocking surface of the slurry barrier strip can block the slurry which is scraped to the cutter collecting position by the scraper, and a pair of inclined surfaces forming the slurry blocking surface can distribute and redistribute the slurry, thereby avoiding or reducing the slurry from gathering at the middle position of the screen printing plate, leading the slurry to be distributed more uniformly, and further achieving the effect of more uniform printing.

The included angle between the first boundary line and the bottom surface is taken as a middle included angle, and the included angle between the second boundary line and the bottom surface is taken as a side included angle; the included angle of the middle part is designed to be 60 degrees at most, the operation space required by the scraper frame is mainly considered, and if the included angle of the middle part is set to be too high, the slurry blocking surface is relatively upright, and the operation of the scraper frame is influenced; the side included angle needs to be smaller than the middle included angle, and the larger the angle difference between the two included angles is, the better the leveling property of the slurry is. The included angle of the middle part can be adjusted according to the viscosity of the slurry, and the more viscous the slurry is, the larger the included angle of the middle part is; the smaller the viscosity of the slurry, the smaller the angle of the included angle in the middle.

When the slurry is on the slurry blocking surface, the slurry mainly bears two directional acting forces: firstly, the slurry flows downwards under the action of gravity and is vertical to the third boundary line; and the other one is the function of a pair of inclined planes which are parallel to the edge of the third boundary line, so that the slurry flows towards the two ends of the length direction of the slurry barrier strip. Under two forces, the slurry flows to the corners of a pair of inclined planes. According to the viscous fluid mechanics boundary layer concept, the thin layer boundary of the pulp contacting with the pulp barrier strips is influenced by the boundary layer, the area outside the boundary layer is still only influenced by the viscosity, gravity and inclined plane of the pulp, and the amount of the pulp of the thin layer of the boundary layer is very small and can be basically ignored. Therefore, for the relatively viscous slurry, a slurry barrier strip with a large included angle in the middle needs to be selected, so that the interaction force caused by the viscosity of the slurry is better overcome; for slurry with low viscosity, the slurry barrier strips with small included angles in the middle parts can sufficiently achieve the leveling effect.

Drawings

FIG. 1 is a schematic view of screen deformation;

FIG. 2 is a schematic top view of a slurry bar;

FIG. 3 is a schematic side view of a slurry bar;

fig. 4 and 5 are schematic perspective views of a slurry bar;

FIG. 6 is a schematic illustration of the use of a paste dam in screen printing;

fig. 7 is a schematic diagram of a slurry split.

Detailed Description

The following description of the embodiments of the present invention will be made with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

The technical scheme of the specific implementation of the invention is as follows:

as shown in fig. 2 to 5, the present invention provides a paste barrier strip for screen printing, including a strip-shaped main body, the strip-shaped main body including: the slurry separation device comprises a pair of vertical end faces 1, a flat bottom face 2, a slurry blocking face, a flat top face 3 and a back face 4, wherein the vertical end faces 1 are respectively arranged at two ends of a strip-shaped main body in the length direction; the pair of end faces 1 are symmetrically arranged in the center of the length direction of the strip-shaped main body, and the pair of end faces 1 are both vertical to the length direction of the strip-shaped main body;

the slurry blocking surface consists of a pair of inclined surfaces 5, and the inclined surfaces 5 are symmetrically arranged at the center of the length direction of the strip-shaped main body; the boundary line of the pair of inclined planes 5 is taken as a first boundary line 6, the first boundary line 6 is vertical to the length direction of the strip-shaped main body, the first boundary line 6 is obliquely arranged right above the bottom surface 2, and the bottom end of the first boundary line 6 is connected with the bottom surface 2; the boundary line of the inclined plane 5 and the end face 1 is taken as a second boundary line 7, and the second boundary lines 7 at the two ends of the strip-shaped main body in the length direction are symmetrically arranged with the center of the strip-shaped main body in the length direction; the second boundary line 7 is obliquely arranged above the bottom surface 2, and the bottom end of the second boundary line 7 is connected with the bottom surface 2; the boundary line between the inclined planes 5 and the bottom plane 2 is taken as a third boundary line 8, the third boundary lines 8 of the pair of inclined planes 5 are symmetrically arranged by the first boundary line 6, and the third boundary lines 8 of the pair of inclined planes 5 are positioned on the same straight line;

the included angle between the first boundary line 6 and the bottom surface 2 is taken as a middle included angle, and the included angle between the second boundary line 7 and the bottom surface 2 is taken as a side included angle; the included angle of the middle part is larger than that of the side edge; specifically, the included angle of the middle part is 45-60 degrees; the included angle of the side edges is 20-45 degrees.

As shown in fig. 6, the present invention further provides a method for using the paste barrier strip, which uses the paste barrier strip in screen printing, and comprises the following steps: taking the position of the screen plate where the printing of the forward stroke or the reverse stroke of the scraper is finished as a cutter retracting position, horizontally placing the slurry blocking strip on the screen plate, enabling the length direction of the slurry blocking strip to be vertical to the stroke direction of the scraper, and enabling a pair of end surfaces 1 of the slurry blocking strip to be respectively abutted against the inner edge of a screen frame (namely a screen frame) of the screen plate; the slurry barrier strip is arranged on the outer side of the cutter collecting position, and the distance between the slurry barrier strip and the cutter collecting position is controlled to be 0.5-1.5 cm.

The invention adds a slurry barrier strip near the printing end position (the cutter collecting position) of the scraper, the slurry blocking surface of the slurry barrier strip can block the slurry which is scraped to the cutter collecting position by the scraper, and a pair of inclined surfaces forming the slurry blocking surface can distribute and redistribute the slurry, thereby avoiding or reducing the slurry from gathering at the middle position of the screen printing plate, leading the slurry to be distributed more uniformly, and further achieving the effect of more uniform printing.

The included angle between the first boundary line and the bottom surface is taken as a middle included angle, and the included angle between the second boundary line and the bottom surface is taken as a side included angle; the included angle of the middle part is designed to be 60 degrees at most, the operation space required by the scraper frame is mainly considered, and if the included angle of the middle part is set to be too high, the slurry blocking surface is relatively upright, and the operation of the scraper frame is influenced; the side included angle needs to be smaller than the middle included angle, and the larger the angle difference between the two included angles is, the better the leveling property of the slurry is. The included angle of the middle part can be adjusted according to the viscosity of the slurry, and the more viscous the slurry is, the larger the included angle of the middle part is; the smaller the viscosity of the slurry, the smaller the angle of the included angle in the middle.

As shown in fig. 7, there are two main directional forces when the slurry is on the slurry blocking face: firstly, the slurry flows downwards under the action of gravity and is vertical to the third boundary line; and the other one is the function of a pair of inclined planes which are parallel to the edge of the third boundary line, so that the slurry flows towards the two ends of the length direction of the slurry barrier strip. Under two forces, the slurry flows to the corners of a pair of inclined planes. According to the viscous fluid mechanics boundary layer concept, the thin layer boundary of the pulp contacting with the pulp barrier strips is influenced by the boundary layer, the area outside the boundary layer is still only influenced by the viscosity, gravity and inclined plane of the pulp, and the amount of the pulp of the thin layer of the boundary layer is very small and can be basically ignored. Therefore, for the relatively viscous slurry, a slurry barrier strip with a large included angle in the middle needs to be selected, so that the interaction force caused by the viscosity of the slurry is better overcome; for slurry with low viscosity, the slurry barrier strips with small included angles in the middle parts can sufficiently achieve the leveling effect.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the technical principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.