JP2006281535A - Screen printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To lessen the nonuniformity of a film thickness, a film width, etc., in the case when two or more films in the same shape are printed in one printing process. <P>SOLUTION: In this screen printing method, first, paste P is put on a plate wherein two or more plate opening parts 21a-21d in the same shape are formed, by moving a scraper SC in one direction on the plate (coating process). Then, the paste P put on the plate is printed on a substrate H by moving a squeegee SQ on the plate in the direction opposite to the above direction (printing process). Herein a pattern of a change in the moving speed of the scraper in the coating process is set in accordance with "the rate of the thickness of the film printed before the start of the coating process at a position in the substrate H corresponding to the plate opening part, to the thickness of the plate opening part 21a etc.". <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention includes a coating step in which a paste or ink-like coating is placed on the plate making by moving the scraper in one direction on the plate making (screen plate), and the squeegee on the plate making. More specifically, the present invention relates to a screen printing method including a printing step of printing the coated material coated on the plate making plate on a printing material by moving the printing plate in a direction opposite to the direction, and particularly relates to setting a moving speed of a scraper.

Conventionally, various screen printing methods of this type are known. For example, there is a method described in Patent Document 1 below.
JP 2003-300302 A

  In the plate making disclosed in the above document, two or more identical plate making openings for printing are formed in a row along the direction of movement of the scraper (ie, along the direction of movement of the squeegee). Yes. That is, in this case, first, in the coating process, the coating material is coated on each plate making opening in the order along the moving direction of the scraper according to the movement (progress) of the scraper.

  Next, in the printing process, the coating material coated on each plate-making opening in the order along the moving direction of the squeegee (that is, the direction opposite to the moving direction of the scraper) according to the moving (advance) of the squeegee. It is printed on the substrate. As a result, in one printing process, two or more identical films respectively corresponding to the “two or more identical plate-making openings” are printed on the printing material.

  The above document does not describe the moving speed of the scraper and the squeegee, but in general, the moving speed of the scraper is kept constant from the start of coating to the end of coating, and the movement of the squeegee. The speed is also kept constant from the start of printing of the coating to the end of printing.

  By the way, when the moving direction of the scraper is opposite to the moving direction of the squeegee and two or more identical films are screen-printed in one printing process, the film thickness and film width Etc., etc. This is considered to be based on the following reasons.

  That is, in this case, the time from when the coating material is coated on a certain plate-making opening until the coating material coated on the same plate-making opening is printed (hereinafter referred to as “coating material residence time”). Is the longest for the plate making opening where the coating is coated first (ie, the plate making opening where the coated coating is printed last), and finally the plate making opening where the coating is coated (Ie, the plate making opening where the coated application is printed first) is the shortest. In other words, the stay time of the applied product varies between “two or more identically shaped plate-making openings”.

  On the other hand, the coating material used in screen printing is generally in the form of a paste or ink and has a relatively low viscosity. Therefore, the coated material coated on the plate-making opening portion enters the plate-making opening portion by gravity (by its own weight) as time passes thereafter. That is, the longer the above-mentioned application stay time is, the generally the amount of entry of the application into the plate making opening immediately before the application is printed (hereinafter referred to as “approach immediately before application”). Become more.

  In addition, generally, the greater the amount of the applied material just before printing, the greater the film thickness, film width, etc. of the printed film. From the above, it is considered that variations in the film thickness, film width, and the like of the film are likely to occur due to the difference in the “applying amount of the applied material just before printing” that occurs with the difference in the “applied material stay time”.

  Therefore, the inventor of the present application has made various studies and experiments on a technique for reducing such “variation in film thickness, film width, etc.”. As a result, it has been found that the above-described “variation in film thickness, film width, etc.” can be reduced by changing the moving speed of the scraper from the start of coating to the end of coating.

  That is, the screen printing method according to the present invention includes a coating step in which a paste-like or ink-like coating is placed on the plate making by moving the scraper in one direction on the plate making, and a squeegee on the plate making. The present invention relates to a screen printing method including a printing step of printing the coated material coated on the plate making plate on a printing material by moving the plate in a direction opposite to the one direction.

  The screen printing method according to the present invention is characterized in that, in the coating step, the moving speed of the scraper is set so as to change between the coating start time and the coating end time of the coated material.

  In this case, in the plate making, two or more plate-shaped openings for printing of the same shape are formed in a row in a direction along the moving direction of the scraper. It is preferable that two or more identical films respectively corresponding to the plate-making openings are printed on the substrate.

  More specifically, the change pattern of the moving speed of the scraper in the coating step is already before the start of the coating step at a position corresponding to the plate making opening in the substrate with respect to the thickness of the plate making opening. It has been found that it is necessary to set as described later according to the ratio of the thickness of the printed film. In addition, since the said ratio is also a ratio of the volume of the coating material that can be filled in the plate making opening with respect to the total volume in the plate making opening, it is hereinafter referred to as “fillable space ratio”.

  That is, the moving speed of the scraper in the coating process is set so as to be gradually slowed between the coating start time and the coating end time when the fillable space ratio is 50% or more. When the space ratio is less than 50%, it is necessary to set the coating rate so that it gradually becomes faster from the start of coating to the end of coating.

  According to this, as described above, variations in film thickness, film width, etc. of the “two or more isomorphic films” printed corresponding to the “two or more isomorphic plate making openings” are reduced. be able to. This is considered to be due to the following reasons.

  That is, when the change pattern of the scraper moving speed in the coating process is set according to the space ratio that can be filled, the “applying amount immediately before printing” is made uniform even though the “applied material staying time” is different. There may be conditions that can be done. As a result, variations in the film thickness, film width, etc. of “two or more identical films” are reduced.

  A screen printing apparatus according to the present invention that implements the above-described screen printing method according to the present invention includes a scraper, a squeegee, and a drive mechanism that drives the scraper and the squeegee. By moving the scraper in one direction above, a paste-like or ink-like coating is placed on the plate making, and the drive mechanism moves the squeegee in the direction opposite to the one direction. The application material coated on the plate making is configured to print on the printing material, and in addition, the drive mechanism has a moving speed of the scraper from the coating start time of the application material to the end of coating. It is configured to drive the scraper to change in time.

  Hereinafter, embodiments of a screen printing method according to the present invention will be described in detail with reference to the drawings. FIG. 1 shows an example of a plate making (screen plate) used for carrying out the screen printing method according to the present invention, FIG. 1 (a) is a plan view thereof, and FIG. 1 (b) is a plan view of FIG. It is the sectional view along the 1-1 line of.

  This plate making is composed of an aluminum rectangular frame 10 having a square cross section and a screen 20 whose outer peripheral portion is fixed over the entire lower surface of the frame 10. A rectangle indicated by a two-dot chain line in the center of the screen 20 indicates a position (outline) of a substrate H (printed material) to be described later disposed under the plate making.

  In the region of the screen 20 corresponding to the substrate H, rectangular plate-making openings 21a to 21d are formed in a row in the same shape in plan view. As shown in FIG. 2 which is an enlarged view of a Z portion in FIG. 1B, the screen 20 is composed of an upper mesh layer M and a lower (photosensitive) emulsion layer E, and is made by plate making. The openings 21a to 21d are formed by making four rectangular holes respectively corresponding to the plate making openings 21a to 21d in the emulsion layer E by exposure.

  As shown in FIG. 1 (a), the plate making openings 21a to 21d form a line in a direction along the moving direction of the scraper SC described later (accordingly, a direction along the moving direction of the squeegee SQ described later). Is formed.

  FIG. 3 shows the substrate H in a state after four isomorphous films Fa to Fd are printed using the above-described plate making, and FIG. 3A is a plan view thereof, and FIG. FIG. 3B is a sectional view taken along line 3-3 in FIG.

  As can be understood from FIGS. 1 and 3, the films Fa to Fd are formed corresponding to the plate making openings 21a to 21d, respectively. Hereinafter, for convenience of explanation, the length W (the long side of the film in plan view) shown in FIG. 3A is defined as “film width”, and the film thickness T shown in FIG. Is defined as “film thickness”.

  Hereinafter, a process of printing the four films Fa to Fd on the substrate H as shown in FIG. 3 by the screen printing method according to the present invention using the plate making shown in FIG. 1 will be briefly described with reference to FIG. To do. FIG. 4 shows a cross section corresponding to FIG. 1B of a screen printing apparatus for performing the screen printing method according to the present invention.

  In this example, the scraper SC and the squeegee SQ can be automatically moved in the left-right direction in FIG. 4 (hence, in the left-right direction in FIGS. 1 and 3) by a known drive mechanism Z and are independently independent. In FIG. 4, it is configured to be automatically movable in the vertical direction.

  The member which comprises the front-end | tip part (part which contacts the paste P (application | coating material)) of the scraper SC is comprised from the urethane rubber, for example. Moreover, the member which comprises the front-end | tip part (part which contacts the paste P) of the squeegee SQ is also comprised from the urethane rubber, for example.

  Note that the angle of the edge portion that contacts the screen 20 (more specifically, the mesh layer M) at the tip portion of the squeegee SQ (that is, the angle formed by the side surface and the bottom surface in the traveling direction at the tip portion) is an acute angle. Preferably there is. Furthermore, it is more preferable that a material having higher hardness (higher Young's modulus) than urethane rubber is inserted at the center of the tip of the squeegee SQ. This has been found to improve the dimensional accuracy and shape accuracy of the printed film.

  As shown in FIG. 4A, first, a predetermined paste P is placed on a predetermined position on the screen 20 by a predetermined amount (on the right side of the plate-making opening 21d in FIG. 4). Next, the scraper SC is lowered to a predetermined height in order to uniformly coat the paste P on the screen 20. In this state, a minute gap is formed between the tip of the scraper SC and the upper surface of the screen 20.

  Next, as shown in FIG. 4B, the scraper SC (and therefore the squeegee SQ) is translated in the left direction in FIG. 4 at a predetermined speed. The scraper moving speed at this time will be described later. Thereby, the paste P is sequentially coated on the screen 20 from the predetermined position to the left in FIG. 4 (coating process). As a result, the paste P is coated on the plate making openings 21d, 21c, 21b, 21a in this order.

  Subsequently, as shown in FIG. 4C, in order to print the coated paste P on the substrate H, the scraper SC is raised to a predetermined height, while the squeegee SQ is lowered to a predetermined height. In this state, the tip of the squeegee SQ is in contact with the upper surface of the screen 20.

  Next, as shown in FIG. 4D, the squeegee SQ (and hence the scraper SC) is translated in the right direction (and hence in the direction opposite to the moving direction of the scraper SC) in FIG. 4 at a predetermined constant speed. Thereby, the paste P coated on the plate making openings 21a, 21b, 21c, and 21d is printed on the substrate H in this order (printing process).

  Then, as shown in FIG. 4 (e), the printing process ends when the tip of the squeegee SQ reaches a position corresponding to the position of the paste P in FIG. 4 (a). As a result, as shown in FIG. 4E, films Fa to Fd are formed (printed) on the substrate H corresponding to the plate-making openings 21a to 21d, respectively.

  Thus, in this example, the “applied material stay time” (here, the paste P is coated on the plate-making opening and then the paste P coated on the same plate-making opening is printed. Is longer in the order of the plate making openings 21d, 21c, 21b, 21a.

  In practice, the above-described “coating process and printing process” are repeated one or more times in this order even after each layer of the films Fa to Fd is formed (printed) on the substrate H. In some cases, new films Fa to Fd are printed on the already printed films Fa to Fd one or more times. In this case, films Fa to Fd composed of two or more layers are formed.

  Next, the scraper moving speed according to the screen printing method according to the present invention will be described. Therefore, first, as shown in FIG. 5, the thickness of the plate-making opening (that is, the sum of the thickness of the mesh layer M and the thickness of the emulsion layer E) is A and corresponds to the plate-making opening in the substrate H. When the thickness of the film F already printed at the position before the start of the coating process is B, the “fillable space ratio (percentage)” is defined according to the following equation (1).

Fillable space ratio = ((A−B) / A) · 100 (1)

  This “fillable space ratio” corresponds to “the ratio of the thickness of the film already printed before the start of the coating process at the position corresponding to the plate-making opening in the substrate to the thickness of the plate-making opening”. To do. This fillable space ratio is a value representing the ratio of the volume of the paste P that can be filled in the plate making opening to the total volume in the plate making opening.

  The inventor has found variations in the film thickness, film width, etc. of the “two or more identical films” (in this case, the film thickness T, film width W of the four films Fa to Fd (see FIG. 3)). In order to reduce the dispersion of the scraper SC in the coating step (see FIG. 4B), the paste P is determined when the fillable space ratio defined by the above equation (1) is 50% or more. When the filling space ratio is less than 50%, it is set so as to be gradually delayed (decelerated) between the start of coating and the end of coating. It was found that it should be set so as to become gradually faster (accelerate) during the period.

  6 to 8 show examples of experimental results performed to confirm this. In this example, three types of patterns (constant, fast → slow (deceleration), slow → fast (acceleration)) are set as the change patterns of the moving speed of the scraper SC. By repeating the “coating process and printing process” four times, films Fa to Fd composed of four layers are formed.

  Hereinafter, the first “coating process and printing process” is the first film printing process, the second “coating process and printing process” is the second film printing process, and the third “coating process and printing process”. The third film printing process and the fourth “coating process and printing process” are referred to as a fourth film printing process.

  In this example, the first and second films are electrode precursors, and examples of the first and second film paste P include platinum (Pt) powder having a predetermined particle diameter, a predetermined organic binder, and A platinum paste made of a predetermined organic solvent is used. Here, the paste of the second film is set slightly softer than that of the first film.

  Thereby, the stable base as a precursor of an electrode can be formed with a relatively hard first film. Furthermore, since a relatively soft second film is formed thereon, irregularities (mesh marks) corresponding to the mesh pattern of the mesh layer M are generated on the upper surface of the electrode precursor (that is, the upper surface of the second film). This makes it difficult to flatten the upper surface of the electrode precursor.

The third and fourth films are the precursors of the piezoelectric film. As the paste P for the third and fourth films, for example, lead zirconate titanate (PZT system) having a predetermined particle size is used as a main component. (PbZrO ₃ -PbTiO ₃ -Pb (Mg1 / 3 Nb2 / 3) O ₃ ) powder, organic binder based on polyvinyl butyral, and organic mixture of α-terpineol and 2-ethylhexanol A piezoelectric paste made of a solvent is used. Again, the fourth film paste is set slightly softer than the third film paste.

  Thereby, the stable base as a precursor of a piezoelectric film can be formed with a relatively hard third film. Furthermore, since a relatively soft fourth film is formed thereon, there are irregularities (mesh marks) corresponding to the mesh pattern of the mesh layer M on the upper surface of the precursor of the piezoelectric film (that is, the upper surface of the fourth film). It becomes difficult to generate, and the upper surface of the precursor of the piezoelectric film can be flattened.

  In FIG. 6, “film width difference” (film width variation) is the difference between the film width of the film Fa and the film width of the film Fd formed in each printing process of the first film printing process to the fourth film printing process. Is shown. In FIG. 6, “average film width” is an average value of the film widths of the films Fa to Fd formed in the printing processes of the first film printing process to the fourth film printing process.

  In FIG. 7, “film thickness difference” (film thickness variation) is the difference between the film thickness of the film Fa and the film thickness of the film Fd formed in each printing process of the first film printing process to the fourth film printing process. Is shown. In FIG. 7, “average film thickness” is an average value of the film thicknesses of the films Fa to Fd formed in the respective printing processes of the first film printing process to the fourth film printing process.

  The difference between the value related to the film Fa and the value related to the film Fd is used as the “film width difference” and “film thickness difference” for the following reason. That is, the film Fa corresponds to the plate making opening 21a having the shortest “applied material stay time”, and the film Fd corresponds to the plate making opening 21d having the longest “applied material stay time”. Therefore, both the “film width” and the “film thickness” tend to have the smallest film Fa and the largest film Fd. Therefore, when the difference between the value related to the film Fa and the value related to the film Fd is used as the “film width difference” and “film thickness difference”, the values of “film width difference” and “film thickness difference” can be increased. , “Film width difference” and “film thickness difference” can be easily compared.

  In FIG. 8, the “printed film thickness” is an average value of the laminated thicknesses of the films Fa to Fd already printed at the start of each printing process of the first film printing process to the fourth film printing process. is there. For example, as shown in FIG. 7, since the average film thickness of the first film is 6 μm, the printed film thickness in the second film printing process is also 6 μm. Further, since the average film thickness of the second film is 5 μm, the printed film thickness in the third film printing step is 11 μm (= (6 + 5) μm).

  In addition, as shown in FIG. 8, the “plate-making opening thickness” is the same value (13 μm) in the first and second film printing steps, and the same value (20 μm) in the third and fourth film printing steps. It has become. This means that the same plate making for electrodes is used in the first and second film printing steps, and the same plate making for piezoelectric films is used in the third and fourth film printing steps.

  As can be understood from FIGS. 6 to 8, in the first and second film printing processes in which the “fillable space ratio” is 50% or more, the scraper speed is reduced for both “film width difference” and “film thickness difference”. When the scraper speed is constant (small → fast), then small when the scraper speed is constant (slow → fast).

  In the third and fourth film printing processes in which the “fillable space ratio” is less than 50%, both the “film width difference” and “film thickness difference” are most effective when the scraper speed is accelerated (slow → fast). Then, it becomes small when the scraper speed is constant, and becomes largest when the scraper speed is decelerated (fast → slow).

  As described above, when the change pattern of the scraper moving speed in the coating process is set in accordance with the fillable space ratio, the above-mentioned “immediately before printing” is performed even though the “applied material stay time” is different. This means that there is a condition that can make (approx.) The “applying amount of approach” uniform.

  As described above, according to the embodiment of the screen printing method according to the present invention, the paste P is placed on the plate making by moving the scraper SC in one direction on the plate making (coating step), Thereafter, the paste P coated on the plate making is printed on the substrate H by moving the squeegee SQ in the direction opposite to the one direction on the plate making (printing step). Here, the thickness of the film already printed before the start of the coating process at the position corresponding to the plate making opening in the substrate H with respect to the thickness of the plate making opening is the change pattern of the scraper moving speed in the coating process. Is set in accordance with the ratio (the “fillable space ratio”). As a result, when two or more identical films are printed in a single printing process, variations in film thickness, film width, and the like can be reduced.

  By the way, as shown in FIG. 9, the mesh layer M, which is the upper layer of the screen 20 shown in FIG. 1 and the like, includes a rectangular low-elasticity mesh M1 and a low-elasticity mesh M1 that are arranged in the center in a plan view. It can comprise from the highly elastic mesh Mh arrange | positioned and joined to circumference | surroundings.

  Here, the low elastic mesh Ml is, for example, a metal mesh, and the plate-making opening described above is formed in a region of the screen 20 corresponding to the low elastic mesh Ml. The linearity and the number of meshes of the low elastic mesh Ml are determined by the size / shape accuracy of the printed film, the film thickness / film width, and the like.

  The high elastic mesh Mh is, for example, a tetron mesh, and has an effect of absorbing the tensile stress generated in the low elastic mesh M1 during printing or the like and suppressing deformation of the plate making opening.

  In this case, the high elastic mesh Mh and the low elastic mesh Ml are joined so that the inner peripheral edge of the high elastic mesh Mh and the outer peripheral edge of the low elastic mesh Ml are overlapped in a frame shape and bonded with an adhesive G. Has been achieved. Thereby, in the area | region corresponding to the said frame-shaped junction part in the upper surface of the screen 20, the convex part corresponding to the layer of the adhesive agent G is inevitably formed.

  Here, when the scraper SC and the squeegee SQ are moved on the screen 20, if these tip portions are brought into contact with the convex portions corresponding to the layer of the adhesive G, the tip portions are damaged, and as a result, This is not preferable because it may adversely affect printing.

  FIG. 10 shows a case where screen printing is performed in the same procedure as in FIG. 4 using the plate making shown in FIG. 9 described above, and each tip of the scraper SC and squeegee SQ is attached to the adhesive. The example in the case of contacting the convex part corresponding to the layer of G is shown. FIG. 10 shows a cross section corresponding to FIG.

  In this case, as shown in FIG. 10B, when the scraper SC is lowered, the tip of the scraper SC becomes a convex portion corresponding to the layer of the adhesive G (right convex portion in FIG. 10). On the other hand, it is located on the right side in FIG. As a result, when the scraper SC moves leftward in FIG. 10 in the subsequent coating process (see FIG. 10C), the tip of the scraper SC can come into contact with the right convex portion.

  Furthermore, in this case, as shown in FIG. 10 (e), when the squeegee SQ is lowered, the tip of the squeegee SQ has a protrusion corresponding to the layer of the adhesive G (the left protrusion in FIG. 10). ) To the left in FIG. As a result, when the squeegee SQ moves rightward in FIG. 10 in the subsequent printing process (see FIG. 10F), the tip of the squeegee SQ can come into contact with the left convex portion.

  On the other hand, in FIG. 11, by making improvements to the procedure shown in FIG. 10, contact of the tip of each of the scraper SC and the squeegee SQ with the protrusion corresponding to the layer of the adhesive G is avoided. An example of the case is shown. FIG. 11 also shows a cross section corresponding to FIG.

  In this case, as shown in FIG. 11B, first, the tip of the scraper SC is positioned on the left side in FIG. 11 with respect to the convex portion corresponding to the adhesive G layer (the right convex portion in FIG. 11). Until then, the scraper SC and the squeegee SQ are moved horizontally in the left direction in FIG. 11, and then the scraper SC is lowered as shown in FIG.

  In other words, when the scraper SC is lowered, the tip of the scraper SC is already positioned on the left side in FIG. 11 with respect to the convex part on the right side. Accordingly, when the scraper SC moves leftward in FIG. 11 in the subsequent coating process (see FIG. 11D), the tip of the scraper SC cannot contact the right convex portion.

  Further, in this case, as shown in FIG. 11 (f), the tip of the squeegee SQ is positioned on the right side in FIG. 11 with respect to the convex portion (left convex portion in FIG. 11) corresponding to the adhesive G layer. Until then, the scraper SC and the squeegee SQ are moved horizontally in the right direction in FIG. 11, and then the squeegee SQ is lowered as shown in FIG.

  In other words, when the squeegee SQ is lowered, the tip of the squeegee SQ is already positioned on the right side in FIG. 11 with respect to the left convex portion. Therefore, when the squeegee SQ moves rightward in FIG. 11 in the subsequent printing process (see FIG. 11H), the tip of the squeegee SQ cannot contact the left convex portion.

  Thus, before lowering the scraper SC, the step of horizontally moving the tip of the scraper SC to a position corresponding to the low elastic mesh M1 (see FIG. 11B), and before lowering the squeegee SQ, the squeegee SQ. Layer of the adhesive G at each tip of the scraper SC and the squeegee SQ by adding a step of horizontally moving the tip of the tip to the position corresponding to the low elastic mesh Ml (see FIG. 11F). The contact to the convex part corresponding to can be avoided.

  By the way, the paste P is paste-like or ink-like and has high fluidity. Therefore, when screen printing is performed according to the procedure shown in FIG. 10 and FIG. 11, the paste P (1) is applied for a short period after the horizontal movement of the scraper SC in the left direction is completed in the coating process. Part) due to its inertia, the position of the tip of the scraper SC at the same point (see FIGS. 10C and 11D, hereinafter referred to as “coating completion position”) is to the left. Moving. As a result, after the coating process is completed and before the printing process is started, the region where the paste P exists extends from the coating completion position to a position in the left direction by a predetermined distance from the coating completion position.

  Similarly, for a short period after the time when the horizontal movement of the squeegee SQ in the right direction is completed in the printing process, the paste P (a part thereof) is, due to its inertia, the tip of the squeegee SQ at the same point. (Refer to FIG. 10F and FIG. 11H, hereinafter referred to as “printing completion position”). As a result, after the printing process is completed (and before the next coating process is started), the region where the paste P exists extends from the printing completion position to a position in the right direction by a predetermined distance from the printing completion position.

  Here, when screen printing is performed according to the procedure shown in FIG. 10, the position of the tip of the squeegee SQ at the time when the horizontal movement of the squeegee SQ in the right direction is started in the printing process (FIG. 10 (e Hereinafter, the “print start position” is referred to as the left side of the coat completion position (see FIG. 10C). As a result, after the coating process, as described above, most of the paste P spreading from the coating completion position to a position in the left direction by a predetermined distance from the coating completion position can be collected by the squeegee SQ. Can be provided.

  In addition, when screen printing is repeatedly performed according to the procedure shown in FIG. 10, the scraper SC at the time when the horizontal movement of the scraper SC in the left direction is started in the coating process that is executed again after the printing process. The position of the leading end (see FIG. 10B, hereinafter referred to as “coat start position”) is on the right side of the print completion position (see FIG. 10F). As a result, most of the paste P spreading from the print completion position to the rightward position by a predetermined distance from the print completion position as described above after the end of the printing process can be collected by the scraper SC, and then executed again. It can be subjected to a coating process.

  On the other hand, when screen printing is performed according to the procedure shown in FIG. 11, the printing start position (see FIG. 11G) is equal to the coat completion position (see FIG. 11D). . In addition, the coat start position (see FIG. 11C) and the print completion position (see FIG. 11H) are also equal. Therefore, the above-described scraper SC or squeegee SQ cannot recover the paste P, and as a result, the number of repetitions of screen printing that can be performed once by placing the paste P on the plate making is reduced. In other words, there arises a problem that the continuous printability of screen printing is lowered.

  In order to deal with this problem, on the plate making (on the screen 20), the region outside the convex portion corresponding to the layer of the adhesive G (that is, the left convex portion due to the adhesive G in FIG. Further, it is preferable to provide a weir for preventing the paste P from spreading to the left region and the right region from the right convex portion by the adhesive G). Thereby, contact with the convex part corresponding to the layer of the above-mentioned adhesive G of each tip part of scraper SC and squeegee SQ can be avoided, suppressing the continuous printability of screen printing.

FIG. 1 shows an example of plate making (screen plate) used in carrying out the screen printing method according to the present invention, FIG. 1 (a) is a plan view thereof, and FIG. 1 (b) is a diagram of FIG. It is the sectional view along line -1. FIG. 2 is an enlarged view of a Z part in FIG. FIG. 3A is a plan view of the substrate after four isomorphous films are printed using the plate making shown in FIG. 1, and FIG. It is the sectional view along line 3-3 in a). 4A to 4E are views showing a printing process by the screen printing method according to the present invention. It is a figure for making easy explanation of the space rate which can be filled up. It is the figure which showed the experimental result for confirming the effect of this invention. It is the figure which showed the experimental result for confirming the effect of this invention. It is the figure which showed the experimental result for confirming the effect of this invention. FIG. 9 shows an example in which the mesh layer which is the upper layer of the screen shown in FIG. 1 is composed of a low elastic mesh and a high elastic mesh arranged and joined around the low elastic mesh. a) is a plan view thereof, and FIG. 9B is a sectional view taken along line 9-9 of FIG. 9A. 10 (a) to 10 (g) show a case where screen printing is performed using the plate making shown in FIG. 9, and each tip of the scraper and the squeegee is formed on a convex portion corresponding to the adhesive layer. It is the figure which showed the printing process in the case of contacting. FIGS. 11A to 11I show a case where screen printing is performed using the plate making shown in FIG. 9, and the convex portions corresponding to the adhesive layer at the tip of each of the scraper and the squeegee. It is the figure which showed the printing process in case contact of this is avoided.

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 ... Screen, 21a-21d ... Plate making opening, E ... Emulsion layer, Fa-Fd ... Film | membrane, H ... Substrate, M ... Mesh layer, P ... Paste, SC ... Scraper, SQ ... Squeegee

Claims (5)

A coating process in which a paste-like or ink-like coating is placed on the plate making by moving the scraper in one direction on the plate making;
A printing step of printing the application coated on the plate making by moving the squeegee on the plate making in a direction opposite to the one direction;
In the screen printing method including
In the coating step, the screen printing method is characterized in that the moving speed of the scraper is set so as to change between the coating start time and the coating end time of the coated material. The screen printing method according to claim 1,
In the plate making, two or more identical plate making openings for printing are formed in a row in a direction along the moving direction of the scraper,
A screen printing method in which, in the printing step, two or more isomorphic films respectively corresponding to the two or more isomorphic plate making openings are printed on the substrate. The screen printing method according to claim 2,
The change pattern of the moving speed of the scraper in the coating step is a film that has already been printed before the start of the coating step at a position corresponding to the plate-making opening in the substrate with respect to the thickness of the plate-making opening. A screen printing method, wherein the screen printing method is set according to a ratio of thickness. The screen printing method according to claim 3.
The moving speed of the scraper in the coating process is as follows:
When the ratio is 50% or more, it is set so as to be gradually slowed from the coating start point to the coating end point of the coating,
A screen printing method, wherein when the ratio is less than 50%, the speed is set so as to be gradually increased from the coating start time to the coating end time of the coated material. Scrapers,
With squeegee,
A drive mechanism for driving the scraper and the squeegee;
By moving the scraper in one direction on the plate making by the drive mechanism, a paste-like or ink-like coating is placed on the plate making, and the squeegee is placed on the plate making by the drive mechanism. A screen printing apparatus that prints the coated material coated on the plate making plate by moving it in the opposite direction to the printing plate;
The screen printing apparatus configured to drive the scraper so that the moving speed of the scraper changes between the coating start time and the coating end time of the coating material.

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