A processing method for a workpiece with a complex pattern

Abstract

The present invention provides a processing method for a workpiece with a complex pattern, comprising the following steps: screen printing a first ink on a screen printing area on the back of the workpiece to obtain a first coating layer with a hollowed-out first pattern; screen printing a second ink of a color different from the first ink on the surface of the first coating layer, the second ink fills the hollowed-out first pattern, and the first ink and the second ink form a second coating layer; laser radium is used to carve a hollowed-out second pattern on the second coating layer; screen printing and filling a third ink at the second pattern, the first ink, the second ink, and the third ink form a complex screen printing coating layer, and a workpiece with a first pattern and a second pattern is obtained. The present invention uses screen printing to hollow out the first pattern and screen printing to fill the hollowed-out first pattern, and then uses laser radium to carve out a hollowed-out second pattern and screen printing to fill the hollowed-out second pattern. The positional accuracy between the first pattern and the second pattern is high and the inks will not interfere. The obtained product has the characteristics of high precision and high yield.

Description

Technical Field

[0001] The invention relates to the technical field of pattern processing, and in particular to a processing method for a workpiece with a complex pattern. Background Art

[0002] In the prior art, it is necessary to screen print multiple times to make complex patterns on workpieces. Currently, a CCD fully automatic screen printer is used to screen print after multiple gripping points are positioned. Since this technology requires multiple gripping points for positioning, the deviation of the pattern position on the workpiece is large and the pattern position accuracy is not high. Due to the poor position accuracy between patterns, it is easy to cause interference between the inks of the patterns, and the product is prone to discoloration problems. Summary of the invention

[0003] The purpose of the present invention is to provide a processing method for a workpiece with a complex pattern, which can produce exquisite complex patterns on the product, and the product has the characteristics of high precision and high yield, meets the needs of users, and is highly practical. The specific technical solution is as follows:

[0004] A method for processing a workpiece with a complex pattern comprises the following steps:

[0005] Step 1: Screen printing a first ink on the screen printing area on the back of the workpiece to obtain a first coating layer having a hollowed-out first pattern;

[0006] Step 2: Screen-print a second ink of a different color from the first ink on the surface of the first coating layer, fill the hollowed-out first pattern with the second ink, and the first ink and the second ink form a second coating layer;

[0007] Step 3: Use laser to carve a hollowed-out second pattern on the second coating;

[0008] Step 4: Fill the hollowed-out second pattern with the third ink by silk-screen printing. The first ink, the second ink and the third ink form a complex silk-screen coating to obtain a workpiece with the first pattern and the second pattern.

[0009] Preferably, the second step further comprises: screen printing the first ink on the second coating layer to make the surface of the second coating layer flush.

[0010] Preferably, in the first step, the first pattern is a CD pattern, the silk-screen printing area is annular, and the inner side of the silk-screen printing area is a circular window area.

[0011] Preferably, the inner and outer circles of the second ink printed in the second step are enlarged by 0.1 mm to 0.2 mm relative to the inner and outer circles of the first pattern hollowed out in the first step.

[0012] Preferably, the inner circle of the first ink printed in the second step is 0.3 mm±0.1 mm away from the outer contour line of the window area.

[0013] Preferably, in the third step, the second pattern includes a triangle pattern and / or a rectangle pattern and / or a LOGO pattern; in the fourth step, the third ink used for patterns of different shapes has different colors.

[0014] Preferably, in the third step, the laser marking speed is 1000mm / S-3000mm / S, and the filling density is 0.02um-0.05um.

[0015] Preferably, the screen printing area of ​​the third ink screen-printed in the fourth step is 0.1 mm-0.2 mm larger than the outline of the corresponding second pattern hollowed out in the third step.

[0016] Preferably, the thickness of the first ink printed in the first step is 3um-5um; the thickness of the second ink printed in the second step is 3um-5um, the thickness of the first ink printed in the second step is 3um-5um; the thickness of the third ink printed in the fourth step is 2um-10um.

[0017] Preferably, the method further comprises: a fifth step of screen printing a fourth ink on the complex screen printing coating; the fourth ink has the same color as the first ink.

[0018] The technical solution of the present invention has the following effects: the present invention firstly adopts silk screen printing to make a hollowed-out first pattern and silk screen printing to fill the hollowed-out first pattern to make a first pattern with a high yield (such as no water ripple defects, no disconnection, no ink shortage, etc.), and then adopts laser laser engraving to make a hollowed-out second pattern and silk screen printing to fill the hollowed-out second pattern. The second pattern is positioned and engraved once by laser engraving, and then ink is filled in the position of the second pattern to display the second pattern effect on the front side. The positional accuracy between patterns is high, and the ink between patterns will not interfere with each other. Finally, a product with a complex pattern of the first pattern and the second pattern is obtained, and the product has the characteristics of high accuracy and high yield.

[0019] In addition to the objects, features and advantages described above, the present invention has other objects, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the back of a workpiece having a hollowed-out first pattern (here, a hollowed-out CD pattern) in the first step of Example 1, wherein there is no ink at the first pattern (i.e., the CD pattern). At this time, the schematic diagram of the front of the workpiece is the same as Figure 1 same;

[0021] Figure 2 This is a schematic diagram of the back side of the workpiece after the hollowed-out CD pattern is filled with silk screen printing in the second step of Example 1;

[0022] Figure 3 for Figure 2 Schematic diagram of the front side of the workpiece, where the CD lines are the color of the second ink (such as gray, etc.);

[0023] Figure 4 This is a schematic diagram of the back side of the workpiece when the first ink is screen-printed on the first coating layer to make the second coating layer surface flush with the first coating layer in Example 1;

[0024] Figure 5 This is a schematic diagram of the back of the workpiece after the second pattern is hollowed out by laser engraving in the third step of Example 1; wherein the rectangular pattern, the rectangular pattern and the LOGO pattern are all hollowed out and not filled with ink;

[0025] Figure 6 This is a front view of the product obtained after screen printing the third ink in the fourth step of Example 1;

[0026] Figure 7 This is a schematic diagram of the back side of the product obtained after screen printing the fourth ink in Example 1;

[0027] Figure 8 This is a front schematic diagram of the product obtained after screen printing the fourth ink in Example 1;

[0028] Fig. 9 This is a front schematic diagram of the direct screen-printed CD pattern in Comparative Example 1;

[0029] Among them: 1-CD pattern, 1.1-hollow CD pattern, 2-window, 3-rectangular pattern, 3.1-hollow rectangular pattern, 4-triangular pattern, 4.1-hollow triangular pattern, 5-LOGO pattern, 5.1-hollow LOGO pattern. DETAILED DESCRIPTION

[0030] Some embodiments of the present invention are described in detail below, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0031] Embodiment 1:

[0032] A method for processing a workpiece with a complex pattern, the workpiece may be a circular lens of a watch, or a panel, base plate, lens, window, etc. used in other electronic products, the processing method specifically comprises the following steps:

[0033] A method for processing a workpiece with a complex pattern comprises the following steps:

[0034] Step 1: Screen print the first ink on the screen printing area on the back of the workpiece to obtain the first coating with hollow CD pattern 1.1; here is a circular CD pattern with a window 2 area reserved in the middle; clean the workpiece before screen printing, see Figure 1 , Figure 1 This is a schematic diagram of the back of a workpiece having a hollowed-out first pattern (here, a hollowed-out CD pattern) in the first step of Example 1, wherein there is no ink at the first pattern (i.e., the CD pattern). At this time, the schematic diagram of the front of the workpiece is the same as Figure 1 same;

[0035] Step 2: Screen print a second ink with a different color from the first ink on the surface of the first coating. The second ink fills the hollowed CD pattern. The first ink and the second ink form a second coating. Figure 2 and Figure 3 ,in Figure 2 Schematic diagram of the back of the workpiece after the hollowed-out CD pattern is filled with silk screen printing in the second step; Figure 3 for Figure 2 Schematic diagram of the front side of the workpiece, where the CD lines are the color of the second ink (such as gray, etc.);

[0036] Step 3: Use laser to carve out the second hollow pattern on the second coating. Figure 5 , Figure 5 This is a schematic diagram of the back of the workpiece after the second pattern is hollowed out by laser engraving; the rectangular pattern, rectangular pattern and LOGO pattern are all hollowed out and not filled with ink; ultrasonic cleaning is recommended after the second pattern is engraved by laser engraving;

[0037] Step 4: Fill the hollowed-out second pattern with the third ink by silk-screen printing. The first ink, the second ink, and the third ink form a complex silk-screen coating to obtain a workpiece with CD pattern 1 and the second pattern. Figure 6 .

[0038] In this embodiment, the second step also includes: screen printing the first ink on the second coating layer to make the surface of the second coating layer flush, see Figure 4 , Figure 4 This is a schematic diagram of the back of the workpiece when the second step is to screen-print the first ink on the first coating to make the second coating surface flush. This can not only avoid the formation of sand holes, but also facilitate the parameter control of subsequent laser engraving operations (such as laser energy, focal length, etc.). There is no need to change parameters, which reduces ink burning or ink residue, and is easy to operate.

[0039] In this embodiment, the first pattern in the first step is a CD pattern, the silk-screen printing area is in a circular ring shape, and the inner side of the silk-screen printing area is a circular window area. High-yield CD patterns are produced by first silk-screening the hollowed-out CD patterns and then silk-screening the hollowed-out CD patterns to fill them. There is no water ripple defect, and there will be no CD pattern disconnection or ink shortage, and the yield is high.

[0040] In this embodiment, the inner and outer circles of the second ink printed in the second step are enlarged by 0.15 mm relative to the inner and outer circles of the first pattern hollowed out in the first step, so that the hollowed out first pattern is filled to avoid the generation of incomplete penetration and sand holes.

[0041] In this embodiment, the inner circle of the first ink printed in the second step is 0.3 mm ± 0.1 mm (preferably 0.3 mm) away from the outer contour line of the window area to prevent the first ink from interfering with the window area and causing ink roughness and sawtooth. It can be selected according to actual needs.

[0042] In this embodiment, the laser marking speed in the third step is 1500 mm / s, and the filling density is 0.03 um. The laser engraving parameters are easy to control.

[0043] In this embodiment, the second pattern in the third step includes a triangle pattern and / or a rectangle pattern and / or a LOGO pattern.

[0044] In this embodiment, in the fourth step, the third ink used in patterns of different shapes has different colors (selected according to customer needs).

[0045] In this embodiment, the silk-screen printing area of ​​the third ink silk-screened in the fourth step is 0.1mm-0.2mm (preferably 0.15mm) larger than the outline of the corresponding second pattern hollowed out in the third step, so as to avoid sand holes and reduce interference between inks, thereby improving the yield of the second pattern.

[0046] In this embodiment, the depth of the second pattern engraved on the workpiece is the same as the thickness of the second coating on the workpiece, ensuring that the second coating can be completely removed, avoiding interference between inks due to unclean laser engraving in some areas, and improving the yield.

[0047] In this embodiment, the thickness of the first ink printed in the first step is 3um-5um; the thickness of the second ink printed in the second step is 3um-5um; the thickness of the first ink printed in the second step is 3um-5um; the thickness of the third ink printed in the fourth step is 2um-10um. The specific thickness value can be selected according to actual needs.

[0048] In this embodiment, the invention also includes: a fifth step of screen printing a fourth ink (preferably 3 mm to 10 mm, selected according to actual needs) on the complex screen printing coating, see Figure 7 and Figure 8 ,in: Figure 7 This is a schematic diagram of the back side of the workpiece. Figure 8 Schematic diagram of the front of the workpiece. In this embodiment, the fourth ink is preferably the same color as the first ink. The protective ink layer can well protect the first pattern and the second pattern on the workpiece, and extend the service life of the product.

[0049] In this embodiment, after the first, second and fourth steps of screen printing, baking is performed, the baking temperature is 150°C-200°C, and the baking time is 3min-10min. In the fifth step, when the fourth ink is screen printed, the baking temperature is 150°C-200°C, and the baking time is 15min-30min, which can be selected according to actual working conditions.

[0050] In this embodiment: the first ink, the second ink, the third ink, and the fourth ink can be selected according to actual needs, and their composition can refer to the prior art. For example, the first ink and the fourth ink are the same and the mass proportion of the main components is: isophorone (C9H14O) 38%, polyurethane resin 30%, methyl methacrylate (C5H8O2) 1%, carbon powder pigment 29%, and additives 2%.

[0051] In this embodiment, the equipment used in all the silk-screen printing steps is a semi-automatic silk-screen printing machine (refer to the prior art). By adopting the scheme of the present invention, a semi-automatic silk-screen printing machine can also be used to produce workpieces with complex patterns with high precision and high yield, which is highly practical.

[0052] Embodiment 2-6

[0053] The difference between Example 2 and Example 1 is that in the third step, the laser marking speed is 1000 mm / s and the filling density is 0.02 um.

[0054] The difference between Example 3 and Example 1 is that in the third step, the laser marking speed is 3000 mm / s and the filling density is 0.05 um.

[0055] The difference between Example 4 and Example 1 is that the screen-printed area of ​​the third ink is 0.1 mm larger than the outline of the corresponding second pattern; and in the second step, the first ink is screen-printed on the second coating layer 0.1 mm larger than the boundary line of the hollow CD pattern.

[0056] The difference between Example 5 and Example 1 is that the screen-printed area of ​​the third ink is 0.2 mm beyond the outline of the corresponding second pattern; and in the second step, the first ink is screen-printed on the second coating layer 0.2 mm beyond the boundary line of the hollow CD pattern.

[0057] The difference between Example 6 and Example 1 is that there is no fifth step of screen-printing the fourth ink on the complex screen-printed coating.

[0058] Comparative Examples 1-7

[0059] Comparative Example 1 uses the existing technology of silk-screen CD pattern combined with the fourth to sixth steps of laser engraving in Example 1 to produce a pattern to obtain a product.

[0060] Comparative Example 2 uses the existing technology of screen printing CD patterns combined with the existing technology of direct screen printing patterns to obtain a product.

[0061] Comparative Example 3 adopts the hollowing out of the first step to the second step of Example 1 to produce CD patterns combined with the direct silk pattern solution in the prior art to obtain a product.

[0062] The difference between Comparative Example 4 and Example 1 is that in the third step, the laser marking speed is 900 mm / s and the filling density is 0.01 um.

[0063] The difference between Comparative Example 5 and Example 1 is that in the third step, the laser marking speed is 3200 mm / s and the filling density is 0.06 um.

[0064] The difference between Comparative Example 6 and Example 1 is that the screen-printed area of ​​the third ink is 0.08 mm larger than the outline of the corresponding second pattern; and in the second step, the screen-printed first ink on the second coating is 0.08 mm larger than the boundary line of the hollow CD pattern.

[0065] The difference between Comparative Example 7 and Example 1 is that the screen-printed area of ​​the third ink is 0.3 mm larger than the outline of the corresponding second pattern; and in the second step, the screen-printed first ink on the second coating is 0.3 mm larger than the boundary line of the hollow CD pattern.

[0066] The performance parameters of the products obtained in Examples 1-6 and Comparative Examples 1-7 are compared in Table 1:

[0067] Table 1 Comparison of performance parameters of the products obtained in Examples 1-6 and Comparative Examples 1-7 (100 pieces of each product were tested)

[0068]

[0069] According to the solutions of Examples 1-6 and Comparative Examples 1-7 combined with the product performance parameters in Table 1, it can be seen that:

[0070] 1. Combining Examples 1-5 and Comparative Examples 1-3, it can be seen that the scheme of the present invention is to adopt a method of using screen printing to hollow out a first pattern (CD pattern), screen printing to fill the hollowed-out first pattern (CD pattern), laser engraving to obtain a hollowed-out second pattern, and screen printing to fill the hollowed-out second pattern, the details are as follows:

[0071] ① After screen printing the hollowed-out first pattern (CD pattern) and screen printing the filled hollowed-out first pattern (CD pattern), a first pattern with a high yield is obtained without problems such as bad water ripples, CD pattern disconnection or ink shortage. In the prior art, when screen printing CD patterns, direct screen printing is used, and the obtained CD patterns will have bad water ripples. In addition, because the position of the CD pattern on the screen is too fine, direct screen printing of the CD pattern will cause the line to be broken, and the CD pattern will be discontinuous, which greatly affects the appearance.

[0072] ② Through the combination of laser engraving of the hollowed-out second pattern and silk-screen filling of the hollowed-out second pattern, the positional accuracy between the first pattern and the second pattern is high, and the ink between the first pattern and the second pattern will not interfere, and the product has high precision and high yield.

[0073] The scheme of screen printing CD pattern and laser engraving pattern in Comparative Example 1 is adopted. Due to the poor water ripples and the poor ink shortage of CD pattern caused by screen printing, the yield rate of the whole product is greatly reduced. The scheme of screen printing CD pattern and screen printing pattern in Comparative Example 2 is adopted. On the one hand, due to the poor water ripples and the poor ink shortage of CD pattern caused by screen printing, the screen printing pattern will cause the defect of difficult alignment and low pattern position accuracy, which greatly affects the product yield. The scheme of hollowing out CD pattern combined with silk pattern in Comparative Example 3 is adopted. Although the CD pattern yield rate is high, the post-screen printing pattern will cause the defect of difficult alignment and low pattern position accuracy, which greatly affects the product yield.

[0074] In addition, in the process of the present invention, the first pattern and the second pattern are produced by using multi-layer silk-screen printing ink, and the combination of ink and ink is adopted, so the product has good stability.

[0075] 2. It can be seen from Examples 1-5 and Example 6 that adding a protective ink layer based on the design concept of the present invention can greatly extend the service life of the product.

[0076] 3. In combination with Examples 1-3 and Comparative Examples 4-5, it can be seen that the selection of laser parameters is very critical. If the parameters are too low, the processing efficiency will be low. If the parameters are too high, the ink removal will not be complete, and the remaining ink will interfere with the subsequent silk-screen ink. In the later processing, different-color spots will appear, thus affecting the yield; if the parameters are too low, the laser will stay in one position for a long time and the energy will be too high, which will burn the silk-screened ink, produce different colors, and affect the yield.

[0077] 4. In combination with Example 1, Examples 4-5 and Comparative Examples 6-7, it can be seen that the selection of the overlapping area range of adjacent ink layers is very critical. If it is too small, it cannot effectively block the sand holes left over from the previous silk-screen printing process. If it is too large, it will cause interference between the inks in adjacent ink layers, resulting in poor color.

[0078] In conventional implementations, the screen printing CD pattern is directly screen printed once, but for finer CD patterns, if they are directly screen printed, the CD pattern position of the corresponding screen plate is too fine, which is easy to block the screen and cause line breakage, such as Fig. 9As shown, the broken line ripples on the screen will appear at the front, back, left and right positions of the product. In this embodiment, through the indirect processing CD pattern method of the first step and the second step, the CD pattern position is not screen-printed in the first step, and the other positions are screen-printed, the screen printing area is large, the screen will not be blocked, and the screen printing accuracy is high. In the second step, ink is filled in the hollowed position to ensure the high accuracy of the CD pattern on the front side, and the accuracy of the CD pattern is within 0.05mm.

[0079] Moreover, in conventional implementations, complex silk-screen patterns are usually formed by superimposing patterns through full silk-screen printing or pad printing (multiple times), which requires multiple positioning points through CCD equipment, with an accuracy of about 0.1mm; in this implementation, all second patterns are processed by laser engraving at one time, and the laser engraved patterns do not have defects such as burrs and sand holes caused by silk-screen printing or pad printing. Then, ink is filled in the hollowed-out positions of the laser engraving on the back, and the pattern effect is displayed from the front. The pattern has high accuracy and can reach ±0.01mm, which improves the accuracy of complex silk-screen patterns. This case uses ordinary silk-screen equipment and laser engraving equipment to achieve high-precision processing of complex silk-screen coatings.

[0080] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for processing a workpiece with a complex pattern, characterized in that: The following steps are involved: Step 1: Screen printing a first ink on the screen printing area on the back of the workpiece to obtain a first coating layer having a hollowed-out first pattern, wherein the first pattern is a CD pattern; Step 2: Screen-print a second ink of a different color from the first ink on the surface of the first coating layer, fill the hollowed-out first pattern with the second ink, and the first ink and the second ink form a second coating layer; Step 3: Use laser radium to carve a hollowed-out second pattern on the second coating; Step 4: Fill the hollowed-out second pattern with the third ink by silk-screen printing. The first ink, the second ink and the third ink form a complex silk-screen coating to obtain a workpiece with the first pattern and the second pattern.

2. The processing method according to claim 1, characterized in that: The second step also includes: screen printing the first ink on the second coating layer to make the surface of the second coating layer flush.

3. The processing method according to claim 2, characterized in that: In the first step, the silk-screen printing area is in a circular ring shape, and the inner side of the silk-screen printing area is a circular window area.

4. The processing method according to claim 3, characterized in that: The inner and outer circles of the second ink printed in the second step are enlarged by 0.1 mm to 0.2 mm relative to the inner and outer circles of the first pattern hollowed out in the first step.

5. The processing method according to claim 3, characterized in that: The inner circle of the first ink printed in the second step is 0.3 mm ± 0.1 mm away from the outer contour line of the window area.

6. The processing method according to any one of claims 1 to 5, characterized in that: In the third step, the second pattern includes a triangle pattern and / or a rectangle pattern and / or a LOGO pattern; in the fourth step, the third ink used for patterns of different shapes has different colors.

7. The processing method according to claim 6, characterized in that: In the third step, the laser marking speed is 1000mm / S-3000mm / S, and the filling density is 0.02um-0.05um.

8. The processing method according to claim 5, characterized in that: The screen printing area of ​​the third ink screen-printed in the fourth step is 0.1 mm-0.2 mm larger than the outline of the corresponding second pattern hollowed out in the third step.

9. The processing method according to claim 7, characterized in that: The thickness of the first ink printed in the first step is 3um-5um; the thickness of the second ink printed in the second step is 3um-5um; the thickness of the first ink printed in the second step is 3um-5um; the thickness of the third ink printed in the fourth step is 2um-10um.

10. The processing method according to claim 1, characterized in that: Also includes: Step 5, screen printing a fourth ink on the complex screen printing coating; The fourth ink has the same color as the first ink.

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