Roller mold surface machining method for film production

Abstract

The invention relates to the technical field of mold processing, and discloses a roller mold surface processing method for film production, which is characterized in that the engraving processing process of the mold surface is divided into a plurality of layers, and each layer adopts a multi-time jumping processing mode; on one hand, the situation that the surface quality of the die is insufficient due to extrusion in the machining process of continuously machining adjacent lines is avoided, and on the other hand, errors possibly existing at a critical point 1 originally are dispersed to four positions of critical points 1, 2, 3 and 4 through four times of machining in a jumping type machining mode each time, so that the Pitch errors are equally divided, and the precision of machining is improved. Possible defects are divided into four positions, so that the defects are reduced, the overall surface machining precision is improved, finally, the quality precision with the error within 0.01 mu m can be achieved, the effect of reducing the obvious difference of the surface lines of the roller mold is achieved, and finally the purpose of improving the machining quality of the roller mold is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of mold processing, and in particular to a surface processing method of a roller mold for film production. Background Art

[0002] Optical films are thin film materials applied to optical components or optical devices, which usually have specific optical properties, such as reflection, transmission, spectroscopy, polarization, etc. Optical films are widely used in various fields, including but not limited to glasses, camera lenses, displays, solar cells, and military and aerospace equipment.

[0003] In the film production process, molds play a vital role. They are mainly responsible for forming and shaping the film to ensure uniform thickness and surface quality of the film. Therefore, the quality of the mold is closely related to the quality of film production. The display module film cutting angles vary. The material cutting utilization rate of normal MD production is relatively low. The roller mold method has high production capacity and good stability, which is obviously superior to the flat engraving mold. Therefore, the roller mold processing method has been widely used, and making roller molds according to product angles is the key to saving production costs.

[0004] The mold will wear out or degrade after use, so it is generally necessary to reprocess it before use to ensure the accuracy. The mold is usually processed by engraving on a high-precision lathe to process the mold surface to achieve the target surface quality.

[0005] The surface processing of the mold is to carve one line at a time. Since the processing process is time-consuming and there are inevitably certain errors in the processing process, the mold surface is prone to splicing lines during the processing, that is, the distance between adjacent lines is uneven, which will cause the quality of the film product to degrade during the use of the mold. Therefore, how to ensure the surface processing quality of mold carving and eliminate or reduce the existence of splicing lines is a problem that needs to be solved now.

[0006] SUMMARY OF THE INVENTION

[0007] The technical problem solved by the present invention is: how to ensure the surface processing quality of mold engraving and eliminate or reduce the existence of splicing lines.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] A method for processing the surface of a roller mold for film production comprises the following steps:

[0010] Choose the mold: Choose the corresponding roller mold according to the target product;

[0011] Mould installation: Fixedly install the selected roller mould on the processing equipment;

[0012] Parameter calculation: Calculate the number of processing lines of the mold; first, the circumference of the cross section of the roller mold is πR, where R is the roller diameter before processing minus twice the processing depth. Then, the number of lines divided in the mold surface processing process is calculated according to the number of processing lines 4n = circumference ÷ processing Pitch, where 4n is the total number of lines, n is the number of single lines, and n is an even number;

[0013] Mold processing: The processing is divided into multiple layers, and the processing of each layer is as follows:

[0014] First, the roller mold is divided into four areas from the side view of the roller mold, and the critical points of each area are 1, 2, 3, and 4 respectively, and then the processing action of one layer is completed in four times;

[0015] The first processing selects critical point 1 as the starting point, and the lines processed each time are alternately processed in the direction of 1→2→3 and 1→4→3, and there is a gap of three lines between two adjacent processed lines until the processing reaches the position of the opposite critical point 3;

[0016] The second processing selects critical point 3 as the starting point, and the lines processed each time are alternately processed in the direction of 3→2→1 and 3→4→1, and there is a gap of three lines between two adjacent processed lines until the processing reaches the position of the opposite critical point 1;

[0017] The third processing selects critical point 2 as the starting point, and the lines processed each time are alternately processed in the direction of 2→3→4 and 2→1→4, and there is a gap of three lines between two adjacent processed lines until the processing reaches the position of the opposite critical point 3;

[0018] The fourth processing selects critical point 4 as the starting point. The lines processed each time are alternately processed in the directions of 4→3→2 and 4→1→2, and there is a spacing of three lines between two adjacent processed lines until the processing reaches the position of the opposite critical point 3.

[0019] In one embodiment of the present invention, in the process of selecting the mold, the dynamic balance index of the roller mold at a rotation speed of 1000 rpm is not more than 50g.

[0020] In one embodiment of the present invention, the concentricity is controlled within 2 μm during the process of installing the mold.

[0021] In one solution of the present invention, in the process of parameter calculation, four decimal places are taken for calculation, and the prism pitch error is controlled below 0.01 μm.

[0022] In one solution of the present invention: when the calculation structure is 10009 according to the number of processing lines 4n=perimeter÷processing Pitch, the total number of lines actually selected for processing is 10008.

[0023] In one solution of the present invention: when the calculation structure is 10007 according to the number of processing lines 4n=perimeter÷processing Pitch, the total number of lines actually selected for processing is 10000.

[0024] In one embodiment of the present invention, the mold processing process is carried out on a high-precision lathe with a concentricity error of less than 2 μm over an axial length of 2 m.

[0025] In one embodiment of the present invention, the mold processing process is carried out in a constant temperature environment, and the ambient temperature fluctuation is within ±1°C.

[0026] In one embodiment of the present invention, a processing area is enclosed outside the processing equipment, and the temperature fluctuation of the processing area is controlled within ±0.5°C.

[0027] In one embodiment of the present invention, the processing of the mold surface is divided into two layers, namely rough processing and fine processing.

[0028] A method for processing the surface of a roller mold for film production according to the present invention has at least one of the following technical effects:

[0030] The present invention divides the engraving process of the mold surface into multiple layers, and each layer adopts multiple, jump-type processing methods, firstly, avoiding the situation that the continuous processing of adjacent lines causes the extrusion during the processing process, resulting in insufficient quality of the mold surface; secondly, through four processings, each of which is a jump-type processing method, the error that may originally exist at the critical point 1 is dispersed to four positions of critical points 1, 2, 3, and 4, thereby evenly dividing the pitch error, dividing the possible defects into four positions, thereby reducing the defects, improving the overall surface processing accuracy, and finally achieving a quality accuracy within 0.01μm, thereby achieving the effect of reducing the obvious difference in the surface texture of the roller mold, and finally achieving the purpose of improving the processing quality of the roller mold. By adopting the jump-type processing method, even if the tool suddenly wears, there will be no obvious large-area color difference, but because of the sharing, the existence of color difference is greatly reduced, thereby improving the yield of the roller mold engraving processing.

[0031] In summary, by adopting this method, the mold processing splicing line can be eliminated or minimized. When manufacturing products, it can be ensured that there are no obvious appearance color differences or obvious dividing lines during routine inspections, and the product width and overall yield can be guaranteed. While ensuring product performance, the process speed and yield can be improved.

[0032] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0034] Figure 1 It is a structural diagram of the mold engraving horizontal engraving processing method;

[0035] Figure 2 It is a structural diagram of the oblique engraving processing method of the mold;

[0036] Figure 3 It is a structural schematic diagram of the roller mold surface of the present invention divided into multiple areas and critical points. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0039] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0040] In the film production process, molds play a vital role. Molds will wear out or degrade after use, so they generally need to be reprocessed before use to ensure accuracy. The mold processing method is generally to carve through a high-precision lathe, so as to process the mold surface to achieve the target surface quality.

[0041] The mold surface processing is to carve one line at a time. The two existing mold carving methods are horizontal carving (please refer to Figure 1 ), oblique engraving (please refer to Figure 2 ). Horizontal engraving is to engrave several times along the axis of the mold to complete the overall engraving action on the mold surface. Oblique engraving is to engrave the surface of the roller mold in a spiral several times in sequence to complete the engraving work on the entire mold surface. Since the engraving process is time-consuming, and there are inevitably certain errors in the process, and the tool has a reciprocating motion on the Z axis, that is, the tool moves from one end of the roller mold to the other end for cutting, and then retreats a certain distance to leave the mold and return to the starting end of the roller mold processing, and then proceeds to the next line of processing, which makes it difficult to avoid errors. Ultimately, during the processing, the mold surface is prone to splicing line problems, that is, the distance between adjacent lines is uneven, which will cause the mold to degrade the quality of film products during use.

[0042] The existing mold surface processing and engraving mostly adopts the method of engraving from the starting point in sequence. The engraving process starts from the starting point and continues to engrave in one direction to the starting point to cover the entire mold surface. Since the roller mold is mostly made of copper, and the hardness of copper is not high, it is easy to be squeezed in sequence, which leads to problems with the splicing line. In addition, the tool may have some unexpected wear during the processing process. The existing sequential processing method is prone to concentrated color difference when the tool is worn, and even the problem of dividing line will occur, resulting in poor appearance of the mold.

[0043] The splicing line is a clear color difference caused by pitch tolerance or depth difference, and it is a visible adjacent parallel line. Since the processing angle and cutting angle of the film are fixed, the existence of the splicing line will seriously reduce the actual width of the product, which is contrary to the original intention of saving production costs. Therefore, how to ensure the surface processing quality of mold engraving and eliminate or reduce the existence of splicing lines is a problem that needs to be solved now.

[0044] To solve the above problems, please refer to Figure 1-3 The present invention provides a method for processing the surface of a roller mold for film production, which is performed using a high-precision lathe and requires that the concentricity error of the axial length of 2m is within 2μm. The processing method comprises the following steps:

[0045] Select the mold: Select the corresponding roller mold according to the target product. During the selection process, since the horizontal and oblique engraving processes have relatively high requirements on the mold itself, the dynamic balance index of the mold is relatively high. During the selection process, the dynamic balance index of the roller mold at a speed of 1000 rpm is not more than 50g. In the actual processing process, it is preferred that the dynamic balance index of the mold can be controlled at about 20g (RPM 1000 rpm).

[0046] Mold installation: The selected roller mold is fixedly installed on the processing equipment, such as a high-precision lathe. During the installation process, the concentricity needs to be controlled within 2μm, and the roller body rotates stably to reduce the impact on the dynamic balance concentricity during processing.

[0047] Parameter calculation: Calculate the number of processing lines of the mold. First, the circumference of the cross section of the roller mold is πR, where R is the roller diameter before processing minus twice the processing depth. In this calculation process, take 4 decimal places (for example 0.0001), and control the prism Pitch error below 0.01μm. Then, according to the number of processing lines 4n = circumference ÷ processing Pitch, the number of lines divided by the mold surface processing process is calculated. In the calculation process, the four-fold method is selected for calculation, and at the same time, the number of single lines is ensured to be an even number. That is, 4n is the total number of lines, n is the number of single lines, and n is an even number. For example, the total number of lines is 10009, and the actual selection is to select a total number of lines of 10008. The actual total number of processing lines is 10008÷4=2502, thereby ensuring that the number of single lines is an even number. For example, when the total number of lines calculated based on the perimeter ÷ processing pitch is 10007, the actual total number of selected lines is 10000, not 10004, because 10004 ÷ 4 = 2501, and the number of single lines is not an even number.

[0048] Mold processing: During the processing, the concentricity of the roller surface needs to be controlled to not exceed 2μm, where the processing pitch unit is μm. In addition, it should be noted that the expansion coefficient of copper itself will change with temperature and have adverse effects on processing. Therefore, the temperature control of the processing room must be strict, which is also a prerequisite for ensuring the processing quality. The ambient temperature fluctuates within ±1℃, and the temperature of the processing area is controlled to fluctuate within ±0.5℃. Specifically, during the processing, first, the roller mold is divided into four areas from the side view of the roller mold (see Figure 3 ), the critical points of each area are 1, 2, 3, and 4 respectively. The processing of each layer of the mold surface is divided into four processes. For example, the mold surface is subjected to one rough machining and one fine machining, then the rough machining and fine machining are divided into four processes.

[0049] The first processing process is cross-made in the directions of (1→2→3) and (1→4→3). That is, the first cut processes the first line on one side (left) of the critical point 1, the second cut processes a line on the other side (right) of the starting point, the third cut processes a line on the left side of the starting point 1, and the fourth cut processes a line on the right side of the starting point, and so on and so forth until both sides are processed to the position of the opposite critical point 3. In this processing process, a jump processing method is adopted, that is, the position of the lines processed by two adjacent cuts is separated by three lines. For example, the number of lines to be processed on the surface of the roller mold is 10000, and they are marked as line 1, line 2, line 3, line 4, line 5, line 6, line 7, line 8... line 10000 according to the directions of critical points 1, 2, 3, and 4, respectively. Then, the processing order of the lines in the processing process is line 1, line 9997, line 5, line 9993, line 9, line 8999..., and the cross processing is carried out in this way until the position of the opposite point 3 is processed.

[0050] The second processing selects critical point 3 as the starting point, and processes in two directions (3→2→1) and (3→4→1). The cross-processing method is the same as the first cross-processing method, using a jump processing method, with three lines between each two cuts.

[0051] The third processing selects critical point 2 as the starting point, and the processing is carried out in a cross-processing manner in two directions (2→3→4) and (2→1→4).

[0052] The fourth processing selects critical point 4 as the starting point, and the processing is carried out in a cross-processing manner in two directions (4→3→2) and (4→1→2).

[0053] After the first processing to the fourth processing, the first layer of the roller mold is processed in four times (rough processing) by using a jump processing method, and then the second layer (finishing), third layer... can be processed in the same way. By using the jump processing method, on the one hand, it is avoided that the continuous processing of adjacent lines will cause the surface quality of the mold to be insufficient due to extrusion during the processing process. On the other hand, through four processings, each of which is a jump processing method, the error that may have existed at the critical point 1 (the existing sequential processing method, the error will accumulate between the starting point and the final point) is dispersed to the four positions of critical points 1, 2, 3, and 4, thereby evenly dividing the pitch error and dividing the possible defects into four positions, thereby reducing the defects and improving the overall surface processing accuracy. Finally, the quality accuracy within the error of 0.01μm can be achieved, thereby achieving the effect of reducing the obvious difference in the surface texture of the roller mold, and finally achieving the purpose of improving the processing quality of the roller mold. At the same time, because it is divided into multiple layers and each layer adopts multiple, jumpy processing methods, even if the tool suddenly wears out, there will be no obvious large-area color difference. Instead, because of the distribution, the existence of color difference is greatly reduced, thereby improving the yield of roller mold engraving processing.

[0054] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of application of the present invention should still fall within the scope of the claims of the present invention.

Claims

1. A method for processing the surface of a roller mold for film production, characterized in that: The steps include: Choose the mold: Choose the corresponding roller mold according to the target product; Mould installation: Fixedly install the selected roller mould on the processing equipment; Parameter calculation: Calculate the number of processing lines of the mold; first, the circumference of the cross section of the roller mold is πR, where R is the roller diameter before processing minus twice the processing depth. Then, the number of lines divided in the mold surface processing process is calculated according to the number of processing lines 4n = circumference ÷ processing Pitch, where 4n is the total number of lines, n is the number of single lines, and n is an even number; Mold processing: The processing is divided into multiple layers, and the processing of each layer is as follows: First, the roller mold is divided into four areas from the side view of the roller mold, and the critical points of each area are 1, 2, 3, and 4, and then the processing action of one layer is completed in four times; The first processing selects critical point 1 as the starting point, and the lines processed each time are alternately processed in the direction of 1→2→3 and 1→4→3, and there is a gap of three lines between two adjacent processed lines until the processing reaches the position of the opposite critical point 3; The second processing selects critical point 3 as the starting point, and the lines processed each time are alternately processed in the direction of 3→2→1 and 3→4→1, and there is a gap of three lines between two adjacent processed lines until the processing reaches the position of the opposite critical point 1; The third processing selects critical point 2 as the starting point, and the lines processed each time are alternately processed in the direction of 2→3→4 and 2→1→4, and there is a gap of three lines between two adjacent processed lines until the processing reaches the position of the opposite critical point 3; The fourth processing selects critical point 4 as the starting point. The lines processed each time are alternately processed in the directions of 4→3→2 and 4→1→2, and there is a spacing of three lines between two adjacent processed lines until the processing reaches the position of the opposite critical point 3.

2. The method for surface processing of a roller mold for film production according to claim 1, characterized in that: In the process of selecting the mold, the dynamic balance index of the roller mold at a rotation speed of 1000 rpm should not exceed 50g.

3. The method for surface processing of a roller mold for film production according to claim 1, characterized in that: During the mold installation process, the concentricity is controlled within 2μm.

4. The method for surface processing of a roller mold for film production according to claim 1, characterized in that: In the process of parameter calculation, four decimal places are taken for calculation, and the prism pitch error is controlled below 0.01μm.

5. The method for surface processing of a roller mold for film production according to claim 4, characterized in that: When the structure is calculated as 10009 according to the number of processing lines 4n = perimeter ÷ processing Pitch, the total number of lines actually selected for processing is 10008.

6. The method for surface processing of a roller mold for film production according to claim 4, characterized in that: When the calculation structure is 10007 according to the number of processing lines 4n = perimeter ÷ processing Pitch, the total number of lines actually selected for processing is 10000.

7. The method for surface processing of a roller mold for film production according to claim 1, characterized in that: The mold processing process is carried out on a high-precision lathe with an axial length of 2m and a concentricity error of less than 2μm.

8. The method for surface processing of a roller mold for film production according to claim 7, characterized in that: The mold processing process is carried out in a constant temperature environment, and the ambient temperature fluctuation is within ±1℃.

9. A method for surface processing of a roller mold for film production according to claim 8, characterized in that: A processing area is formed outside the processing equipment, and the temperature fluctuation in the processing area is controlled within ±0.5℃.

10. The method for surface processing of a roller mold for film production according to claim 1, characterized in that: The processing of the mold surface is divided into two layers, namely rough machining and fine machining.

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