JP2004001535A - Method for manufacturing mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a mold suitable for forming a cavity insert which is placed in the mold and has a minute pattern accurately and efficiently. <P>SOLUTION: In the method for manufacturing the mold having the cavity insert 34 having the minute pattern 11, when the cavity insert 34 is manufactured, a cut master 10 with minute pattern 11 formed in advance is formed. Next, a transfer master 32 is formed from the cut master 10 by a hot pressing, and the cavity insert 34 is formed from the transfer master 32 by an electric casting method. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a mold, and more particularly, to a method for manufacturing a mold suitable for forming a nest having a fine pattern disposed in the mold.
[0002]
[Prior art]
For example, a prism sheet or a prism light guide used in a backlight device of a liquid crystal display is formed of a resin, and has a fine surface on its surface to improve the state of emitted light (for example, a scattering state). A pattern (specifically, a saw-like pattern) is formed.
[0003]
Generally, this type of prism sheet or prism light guide is manufactured using a mold. Further, since a prism sheet or a prism light guide usually has a complicated shape, a mold using a nest is used as a mold.
[0004]
Further, the fine pattern on the mold side corresponding to the fine pattern formed in the nest is formed on the nest side, so that it is necessary to form a fine pattern in the nest. At this time, a mold for a plastic optical component having a fine pattern requires extremely high shape precision and mirror finish.
[0005]
As described above, since the nest needs to be formed with high precision, conventionally, as a method for forming the nest, an electric casting method, precision machining (precision cutting), or the like has been used. In addition, since it is difficult to obtain a large number of pieces by the conventional manufacturing method, nests are manufactured by individually processing each one.
[0006]
Specifically, when the nest is manufactured by using the electroforming method, a nest having a relatively large thickness is integrally manufactured, and thus the nest formed by the electroforming method has a large thickness. It had a configuration having a cast layer.
[0007]
In addition, when nesting is manufactured using precision cutting, cutting is usually performed using a cutting tool, but light oil or kerosene has been used as the cutting oil used in this cutting. . Further, when supplying the cutting oil to the cutting position, the cutting oil is mixed with air by air blow to form a mist, and the mist-shaped cutting oil is supplied to the cutting position.
[0008]
Further, since the fine pattern is a saw-like pattern as described above, it is necessary to form many triangular groove-like patterns. For this reason, conventionally, when a fine pattern is formed using precision cutting, after processing one triangular groove-shaped pattern, the cutting tool is once lifted up and separated from the nest, until the position of the next pattern to be formed The cutting tool was moved, and the next triangular groove-like pattern was processed thereon. That is, conventionally, it was necessary to move the cutting tool in both the plane direction and the vertical direction with respect to the nested processing surface.
[0009]
In addition, when performing pre-processing on the nesting surface before performing precise cutting, grinding has conventionally been performed in the longitudinal direction of the material. In addition, as a material of the nest, a soft material having good machinability such as aluminum, copper, or brass is generally applied, and thereby, the machinability has been improved.
[0010]
In addition, a machining apparatus that performs precision cutting is provided with a feed mechanism for feeding a nest that is a workpiece. The feed mechanism has a stage on which a nest is mounted, and a drive device for driving the stage. Conventionally, a ball screw mechanism has been used as a driving device, and a configuration using a roller guide surface has been generally used to guide the movement of a stage.
[0011]
Further, at the time of machining, it is necessary to align the tip of the cutting tool with the machining start position with high precision. Conventionally, this alignment has been performed using a microscope.
[0012]
[Problems to be solved by the invention]
However, in the above-described conventional method, since the nesting is individually performed one by one, a processing error necessarily occurs in each nest to be manufactured. However, in a plastic optical component having a fine pattern, a change of about 1/10 μm also affects the optical characteristics, and the conventional manufacturing method has a problem that the reproducibility of the optical characteristics is deteriorated.
[0013]
In addition, when a plurality of plastic optical components are taken by mounting a plurality of nests having such processing variations in a mold, the flow error of the resin in the cavity of the mold becomes uneven due to this processing error, Therefore, man-hours were required to adjust the gate balance.
[0014]
Further, in the case where a nest is conventionally manufactured by using an electroforming method, since an integrated mold nest having a thick electroformed layer has been manufactured, generally, a long number of days of about 30 to 50 days is required to manufacture the nest. This is necessary, and there is a problem in that nesting is complicated.
[0015]
In the case where nests are manufactured using precision cutting, conventionally, light oil or kerosene is used as cutting oil, mixed with air blow and supplied in the form of mist. On the contrary, in the case of micro-mirror cutting with a diamond tool, the clearance (flank, rake face) in the area being cut is small and there is a shortage of cutting oil supply. However, there is a problem that the steel is easily worn and damaged.
[0016]
Conventionally, when a fine pattern is formed using precision cutting, after processing one triangular groove pattern, the cutting tool is once raised upward, separated from the nest, and then the position of the next pattern to be formed. The cutting tool was moved until the next pattern was processed.
[0017]
However, in this processing method, the cutting tool involves an operation of moving the cutting tool in the vertical direction, so that even if the patterns are adjacent to each other, the cutting tool height and posture (angle) slightly change, and therefore, the gloss of the processing surface changes. There was a problem that it would.
[0018]
Also, in the past, grinding was performed in the longitudinal direction of the material as pre-processing, but when fine mirror surface pattern cutting is performed with grinding processing, surface irregularities due to grinding marks and abrasive grains that bite intermittently hit the cutting edge. , Causing cutting edge damage and shortening the tool life.
[0019]
In the past, soft materials with good machinability such as aluminum, copper and brass were used as nesting materials.However, these metals are soft and deteriorate quickly when used directly in a mold. There is a problem that the number of formed resin molded articles is small and the mold life is short. In addition, since aluminum, copper, brass, and the like are easily oxidized, some materials have already started to be oxidized during processing, and have lost their mirror-like properties when processing is completed.
[0020]
Conventionally, a feed mechanism for feeding a nest as a workpiece is a ball screw mechanism and a roller guide surface is used to guide the movement of the stage. As a result, there is a problem that a streak is generated such that the cutting tool or the insert vibrates and intersects the slope of the triangular groove at an angle almost perpendicular to the cutting tool feeding direction.
[0021]
Further, in the related art, since a microscope is used to align the tip of the cutting tool with the processing start position, it is difficult to determine a reference portion when a fine pattern already exists on the entire surface of the nest.
[0022]
The present invention has been made in view of the above points, and has as its object to provide a method of manufacturing a mold capable of forming a nest having a fine pattern with high accuracy and efficiency.
[0023]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides:
In a method for manufacturing a mold having a nest on which a fine pattern is formed,
When manufacturing the nest,
First, a cutting master on which a fine pattern is formed in advance is formed,
Subsequently, a transfer master is formed from the cutting master by hot pressing,
Subsequently, a nest is formed from the transfer master by using an electroforming method.
[0024]
According to the above invention, by forming a cutting master on which a fine pattern is formed in advance, subsequently forming a transfer master from the cutting master by hot pressing, and subsequently forming a nest from the transfer master using an electroforming method. It is possible to form many nests from the same transfer mold.
[0025]
Further, since a large number of nests are formed from the same transfer mold, all the nests formed have the same shape and there is no processing error. Therefore, when an optical component is formed using the nest, the reproducibility of the optical characteristics can be improved.
[0026]
Further, when a plurality of nests are mounted on a mold to take a large number of resin-formed products, the flow balance of the resin in the cavity of the mold is made uniform, so that it is not necessary to adjust the gate balance. Further, in small-scale molding such as trial production, a thin electroformed plate can be manufactured in a short turn.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
[0028]
FIG. 1 is a view showing a method for manufacturing a mold according to a first embodiment of the present invention. The mold 22 which is the object of the present embodiment is a mold which incorporates the nests 20 and 21 and is molded with a resin. , An optical component 26).
[0029]
Further, the optical component 26 to be molded in the present embodiment needs to form a fine pattern 26a for scattering light (see FIG. 1 (G)) on one surface thereof. Are formed. The present embodiment is characterized by the method of manufacturing the nest 20 having the fine pattern 11, and the other configuration is not different from the conventional manufacturing method. The explanation will be centered.
[0030]
To manufacture the nest 20, first, the cutting master 10 shown in FIG. 1A is prepared. The cutting master 10 is manufactured by a manufacturing method according to each embodiment described later, and a fine pattern 11 corresponding to the fine pattern 26a is formed on one surface thereof with high precision.
[0031]
The cutting master 10 is mounted in a container 12 as shown in FIG. Then, the transfer die 16 is formed by pouring the silicone rubber 14 into the container 12 (molding method). After the transfer mold 16 is formed, the cutting master 10 is subsequently removed from the transfer mold 16 as shown in FIG. At this time, an inverted pattern 15 corresponding to the fine pattern 11 is formed on the transfer die 16.
[0032]
Subsequently, as shown in FIG. 1D, a metal 18 serving as a material of the insert 20 is melted and poured into the transfer mold 16 (precision casting method). Then, after cooling the metal 18 for a predetermined time and hardening the metal 18, the metal 18 is removed from the transfer mold 16, thereby forming the nest 20. At this time, since the reverse pattern 15 is formed on the transfer die 16, the reverse pattern 15 is transferred to the nest 20, whereby the fine pattern 11 is formed on the nest 20.
[0033]
As in the present embodiment, a cutting master 10 on which a fine pattern 11 is formed is formed in advance, and a transfer die 16 is formed from the cutting master 10 by using a molding method. By forming the nest 20 using the precision casting method, it is possible to form a plurality of nests 20 from the same transfer die 16. Therefore, the nest 20 can be formed efficiently, and since the plurality of nests 20 to be formed are formed from the same transfer die 16, all the nests 20 to be formed have the same shape and a processing error. There is no such thing as existing.
[0034]
FIGS. 1F and 1G show a molding process for manufacturing the optical component 26 using the nest 20 manufactured as described above. The mold 22 shown in this embodiment is configured to manufacture two optical components 26 at the same time, that is, to perform so-called multi-cavity.
[0035]
In order to manufacture the optical component 26 using the mold 22, a pair of mold halves 22a and 22b are clamped, and as shown in FIG. The mold resin 24 is charged into a cavity formed between the mold half 22b and the insert 21.
[0036]
At this time, the mold resin 24 moves in the cavity, but since the two nests 20 provided in the mold 22 have the same shape as described above, the flow balance of the mold resin 24 in the mold 22 is maintained. Are made uniform, so that it is not necessary to adjust the gate balance.
[0037]
FIG. 1G shows a state where the optical component 26 is molded and the pair of mold halves 22a and 22b are separated. Since the optical components 26 formed in this manner are formed by the same nest 20, the reproducibility of the optical characteristics can be improved.
[0038]
Next, a method of manufacturing a mold according to a second embodiment of the present invention will be described.
[0039]
FIG. 2 is a view showing a method of manufacturing a mold 23 according to a second embodiment of the present invention. The mold 23 to which the present embodiment is applied is used when forming a prototype of the optical component 26 by mounting a nest 34 for trial operation. In FIG. 2, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.
[0040]
In order to manufacture the nest 21 in the present embodiment, similarly to the first embodiment, the cutting master 10 shown in FIG. 2A in which the fine pattern 11 corresponding to the fine pattern 26a is formed on one surface with high precision. prepare. Then, as shown in FIG. 2B, the cutting master 10 is disposed so as to face the acrylic plate 28, and a pressing plate 30 is disposed on the back surface of the acrylic plate 28. That is, the cutting master 10 and the holding plate 30 are arranged so as to sandwich the acrylic plate 28.
[0041]
Subsequently, as shown in FIG. 2C, the acrylic plate 28 is pressed by the cutting master 10 and the pressing plate 30 while performing the heat treatment, thereby forming the transfer master 32. Subsequently, as shown in FIG. 2D, the transfer master 32 is removed from the cutting master 10 and the pressing plate 30 by separating the cutting master 10 from the pressing plate 30. At this time, the transfer pattern 15 is formed on the transfer master 32 by transferring the fine pattern formed on the cutting master 10.
[0042]
When the transfer master 32 is formed as shown in FIG. 2E, electroforming is performed based on the transfer master 32, and as shown in FIGS. Cast plate) is formed.
[0043]
At this time, in the present embodiment, since the nest 34 is a trial operation, its plate thickness is reduced. Specifically, the thickness of the nest 34 is about 0.1 to 0.5 mm, and thus the nest 34 has a sheet-like shape.
[0044]
In the present embodiment, similarly to the first embodiment, a cutting master 10 on which a fine pattern 11 is formed is formed in advance, a transfer master 32 is formed from the cutting master 10, and an electric casting is performed from the transfer mask 32. By forming the nest 34 using the method, it is possible to form a plurality of nests 34 from the same transfer master 32.
[0045]
Therefore, the inserts 34 can be formed efficiently, and since the formed inserts 34 are formed from the same transfer master 32, the inserts 34 to be formed all have the same shape and a processing error. There is no such thing as existing. In addition, since the trial insert 34 is in the form of a thin sheet, it can be mass-produced and can be formed in a short turn. However, in the mounting to the mold 23, the mounting property is deteriorated due to the thinness. For this reason, in this embodiment, this problem is solved by adopting a configuration in which the insert 34 is attracted to the mold 23.
[0046]
FIGS. 2H and 2I show a molding process for manufacturing the optical component 26 using the nest 34 manufactured as described above. The mold 23 shown in this embodiment is also configured to manufacture two optical components 26 at the same time, that is, perform so-called multi-cavity.
[0047]
The mold 23 includes a pair of mold halves 23a and 23b, and a sheet-shaped insert 34 is mounted on the mold halves 23a. At this time, a suction pipe 36 is provided on the mold half 23a, the outer end of which is connected to a suction device (not shown), and the inner end is opened at the mounting position of the insert 34. I have.
[0048]
Therefore, the nest 34 is attached to the mold half 23a, and then a negative pressure is applied to the suction pipe 36 by the suction device, so that the nest 34 is adsorbed to the mold half 23a. With this configuration, even the thin sheet-shaped nest 34 can be reliably mounted on the mold 23 (the mold half 23a).
[0049]
In order to manufacture the optical component 26 using the mold 23 having the above configuration, a pair of mold halves 23a and 23b are clamped and disposed on the mold half 23a as shown in FIG. The mold resin 24 is charged into a cavity formed between the nest 34 and the nest 21 provided in the mold half 23b.
[0050]
At this time, the mold resin 24 moves in the cavity, but also in this embodiment, since the two nests 34 provided in the mold 23 have the same shape, the flow of the mold resin 24 in the mold 23 The balance is made uniform, so that it is not necessary to adjust the gate balance.
[0051]
FIG. 2I shows a state in which the optical component 26 is molded and the pair of mold halves 23a and 23b are separated. Since the optical component 26 formed in this manner is formed by the same nest 34, the reproducibility of its optical characteristics can be improved.
[0052]
Next, a method for forming a fine pattern according to a first embodiment of the present invention will be described. The method for forming a fine pattern according to the present embodiment is applied when the fine pattern 11 is formed on the cutting mask 10 described above.
[0053]
FIG. 3 is a diagram for explaining a method for forming the fine pattern 11 according to the first embodiment of the present invention. In this embodiment, as shown in the figure, a cutting tool 40 (diamond cutting tool) is used to form a fine pattern 11 on a cutting mask 10 made of metal.
[0054]
Specifically, a triangular groove pattern is formed by cutting the surface of the cutting mask 10 with a cutting tool 40, and this operation is repeated a plurality of times to arrange a plurality of triangular groove patterns side by side. (See FIG. 5A).
[0055]
When the cutting mask 10 made of metal is cut with the cutting tool 40 as described above, the purpose is to suppress the temperature rise at the cutting position, to improve the workability by the cutting tool 40, and to extend the life of the cutting tool 40. 44 (shown in satin). The cutting oil 44 enters the gap formed between the cutting tool 40 and the surface of the cutting master 10 and the gap formed between the cutting tool 40 and the cutting tool 42 and performs the above-described functions.
[0056]
Conventionally, light oil or kerosene is used as the cutting oil, mixed with air blow and supplied to the cutting position in the form of a mist. On the contrary, in the case of micro-mirror cutting with a diamond tool or the like, the gap (flank face, rake face) in the cutting area is small, and the cutting oil is supplied only to the positions indicated by arrows A2 and B2 in FIG. A shortage of supply caused local heat generation and wear and damage of the cutting tool due to the heat generation.
[0057]
On the other hand, the present embodiment is characterized in that cutting is performed using a cutting oil 44 to which a surfactant is added. Specifically, a surfactant is added to a base oil having a low viscosity and a high flash point such as an electric discharge machining oil, mixed with an air blow, and supplied to the tip of a cutting tool in the form of a mist. In addition, a highly volatile solvent such as IPA (isopropyl alcohol) is mixed, and the heat dissipation effect is enhanced by utilizing the volatility.
[0058]
By using the cutting oil 44 configured as described above, it becomes possible to supply the cutting oil 44 deeper into the gap between the cutting tool and the cutting master in the cutting part. That is, the cutting oil 44, which could be conventionally supplied only up to the position indicated by the arrows A2 and B2 in FIG. 3, can be supplied up to the position indicated by the arrows A1 and B1. Wear and damage can be prevented.
[0059]
Next, a method for forming a fine pattern according to a second embodiment of the present invention will be described. FIG. 4A is a view for explaining a method for forming a fine pattern according to a second embodiment of the present invention, and FIG. 4B shows a conventional method for forming a fine pattern for comparison. ing.
[0060]
First, a conventional method for forming a fine pattern will be described with reference to FIG. In the figure, the movement locus of the cutting tool is indicated by an arrow. As shown in the drawing, when forming a fine pattern using a cutting tool, first, the cutting tool 10 is processed by moving the cutting tool relatively in the direction of arrow Y1 to form one triangular groove pattern.
[0061]
When the processing of the single triangular groove pattern is completed, the cutting tool moves the cutting tool upward by a predetermined amount in the direction of arrow Z1 (ie, upward), and then moves the cutting tool in the direction of arrow Y2, the direction of arrow Z2 (downward), The cutting tool is sequentially moved in the direction of the arrow X2 to move the cutting tool to the next cutting start position on the cutting master 10. Then, the next triangular groove pattern is processed by moving the cutting tool in the direction of the arrow Y1, and thereafter, this operation is repeated to form a fine pattern.
[0062]
However, in this conventional method, since the cutting tool involves an operation of moving the cutting tool in the vertical direction (Z1, Z2 directions), even if the patterns are adjacent to each other, the cutting tool height and the posture (angle) are slightly changed, so that the surface to be processed is glossy Is inconvenient as described above.
[0063]
On the other hand, in the processing method according to the present embodiment, as shown in FIG. 4A, when the cutting master 10 is cut by the cutting tool, the cutting tool 10 is cut in the plane direction (the direction of the arrow X1, X2 and the direction of the arrow Y1, Y2). Is characterized in that machining is performed in a fixed state while movement in the height direction of the cutting tool (in the directions of arrows Z1 and Z2) is fixed.
[0064]
That is, when the processing of one triangular groove pattern is completed, the cutting tool moves in the direction of arrow X1 to move along the locus of the outer circumference of the cutting master 10 indicated by arrow D, and moves to the next cutting start position.
[0065]
As described above, the method of forming the fine pattern without moving the cutting tool in the height direction (the directions of the arrows Z1 and Z2) makes it possible to eliminate the variation in the cutting tool height direction. This makes it possible to prevent a change in gloss.
[0066]
Next, a method for forming a fine pattern according to a third embodiment of the present invention will be described. FIG. 5A is a view for explaining a fine pattern forming method according to a third embodiment of the present invention, and FIG. 5B shows a conventional fine pattern forming method for comparison. ing.
[0067]
First, a conventional method for forming a fine pattern will be described with reference to FIG. The cutting master 10 is formed by casting or the like, but since the surface roughness is large in a blank state immediately after being formed, the cutting master 10 is generally subjected to a grinding process before performing a fine pattern processing. You.
[0068]
However, if a process of forming a fine pattern using the cutting tool 10 is performed on the cutting master 10 in a state in which the grinding process is performed, as shown in FIG. Because of the presence of fine irregularities and cut-off abrasive grains, the cutting tool intermittently hits these irregularities and abrasive grains, causing cutting edge damage and shortening the life of the cutting tool.
[0069]
On the other hand, the present embodiment is characterized in that pre-processing for removing the surface layer is performed on the surface of the cutting master 10 in a blank state where fine irregularities and abrasive grains are present.
[0070]
That is, in the present embodiment, before performing the processing of the fine pattern, for example, an R bit is sent in the same direction as the feeding direction of the bit for forming the fine pattern, and the surface layer (a layer containing fine irregularities and cut-in abrasive grains) is formed. The removal process (this process is called self-cut) is performed.
[0071]
By performing this pre-processing, the surface of the cutting master 10 is flattened, and the smooth surface 52 is formed. Therefore, at the time of processing the fine pattern shown in FIG. 5A, the cutting tool performs cutting on the smooth surface 52 on which fine irregularities and no abrasive grains are present. As a result, the cutting tool does not intermittently hit these irregularities or abrasive grains, thereby preventing the cutting edge from being damaged and extending the cutting tool life.
[0072]
Next, a method for forming a fine pattern according to a fourth embodiment of the present invention will be described. In this embodiment, first, a nickel layer to which at least one of phosphorus and selenium is added is formed on the surface of the cutting master 10 in a blank state, and then the nickel layer formed on the surface of the cutting master 10 is cut by a cutting tool 40. And thereby forming a fine pattern.
[0073]
More specifically, electroless nickel plating of 13% of phosphorus is formed on a cutting master 10 made of pre-hardened steel to a thickness of about 0.3 mm, and the nickel layer is cut by a cutting tool 40 to form a fine pattern. That is, in the present embodiment, a fine pattern is formed by performing a cutting process on the nickel layer formed on the cutting master 10 instead of directly performing the cutting process on the cutting master 10.
[0074]
The nickel layer having the above composition has a high specularity, is hard and is not easily damaged, and has a high machinability, so that the cutting tool is hardly damaged and a machining with a very long cutting length can be performed.
[0075]
FIG. 6 is a diagram for demonstrating the effect of the method for forming a fine pattern according to the present embodiment. 6 (A) to 6 (C) show a case where various nickel films of about 0.3 mm are formed on a cutting master 10 made of a pre-hardened steel, and a cutting process of a cutting length of 25.5 m is performed on these with a diamond tool. It is a figure which expands and shows the cutting edge 46 of the cutting tool 40 (40A-40C).
[0076]
FIG. 6 (A) relates to the present embodiment, in which a cutting master 10 made of pre-hardened steel is formed by electroless nickel plating of phosphorus 13% to a thickness of about 0.3 mm and a cutting length of 25.5 m is used. The cutting edge 46 of the cutting tool 40A when the cutting process is performed is shown in an enlarged manner.
[0077]
FIG. 6B shows a comparative example, in which an electroless nickel plating of 7% of phosphorus is formed on a cutting master 10 made of pre-hardened steel to a thickness of about 0.3 mm, and a cutting length of 25.5 m is obtained. The cutting edge 46 of the cutting tool 40B when the cutting process is performed is shown in an enlarged manner.
[0078]
Further, FIG. 6C also shows a comparative example, in which an electroless nickel plating containing no phosphorus is formed into a film of about 0.3 mm on a cutting master 10 made of pre-hardened steel, and the cutting length is 25.5 m. The cutting edge 46 of the cutting tool 40C when the cutting process is performed is shown in an enlarged manner.
[0079]
As is clear from FIG. 6 (A), when a nickel layer containing 13% of phosphorus is formed on the cutting master 10 according to the present embodiment, no chipping or wear occurs on the cutting tool 40A. Therefore, it was proved that the bite was hardly damaged.
[0080]
On the other hand, as shown in FIG. 6 (B), when a nickel layer containing 7% of phosphorus is formed on the cutting master 10, a cutting part 48 is generated in the cutting tool 40B. Further, as shown in FIG. 6C, when the cutting master 10 is formed with a nickel layer that does not contain phosphorus, a curved blade wear portion 50 is generated in the cutting tool 40C. Therefore, by forming a nickel layer containing 13% of phosphorus on the cutting master 10 as in the present embodiment and performing a cutting process on the nickel layer to form a fine pattern, the tool life can be extended.
[0081]
Next, a method for forming a fine pattern according to a fifth embodiment of the present invention will be described. In the present embodiment, a fine pattern is formed by cutting a nickel layer formed on the surface of the cutting master 10 with a cutting tool by performing the above-described fourth embodiment, and then the cutting master on which the fine pattern is formed. 10 is characterized by performing a heating process and subsequently performing a slow cooling process.
[0082]
FIG. 7 shows the relationship between the heating time and the Vickers hardness when heat treatment was performed on the nickel layer, and FIG. 8 shows the Vickers hardness and stress cracking when the cooling was performed after the heat treatment. It is a figure showing a situation.
[0083]
In this embodiment, after the fine pattern is cut into the above-mentioned nickel plating layer (containing 13% of phosphorus), a heat treatment of holding at 300 ° C. for 90 minutes is performed, and then a process of gradually cooling to a normal temperature in a heating furnace is performed. Was. As a result, as shown in FIG. 8, the Vickers hardness was 700 to 900, and the composition was cured to a Vickers hardness of about 750 without generating stress cracking.
[0084]
As described above, by performing an appropriate heat treatment after the nickel layer processing, it is possible to form the cutting master 10 having a high hardness without stress cracking or deterioration of the mirror finish, and thus a highly accurate and highly reliable Manufacturing can be performed.
[0085]
Next, a fine pattern processing apparatus according to a first embodiment of the present invention will be described. FIG. 9 is an enlarged view showing a main part of the fine pattern processing apparatus 63 according to the first embodiment of the present invention.
[0086]
The fine pattern processing apparatus 63 according to the present embodiment includes a cutting oil supply nozzle 60 (cutting oil supply unit) that supplies the cutting oil 44 toward the cutting position of the cutting tool 40, and a rust prevention oil 58 similarly to the cutting position of the cutting tool 40. And a rust-preventive oil supply nozzle 62 (rust-preventive oil supply unit) for supplying the cutting oil 44 and the rust-preventive oil 58 from the nozzles 60 and 62 to the cutting position of the cutting tool 40 simultaneously. It is characterized by the following.
[0087]
Specifically, the cutting oil supply nozzle 60 is disposed on the front side (the arrow Y2 side) with respect to the feed direction of the cutting tool 40, and the rust prevention oil supply nozzle 62 is disposed on the rear side (with respect to the feed direction of the cutting tool 40). (Arrow Y1 side).
[0088]
With this configuration, the cutting oil 44 is supplied to the front portion of the cutting tool 40 with respect to the machining position, so that the cutting position can be cooled and the workability can be improved. Further, since the rust-preventive oil 58 is supplied to the rear part of the cutting tool 10 with respect to the processing position, it is possible to prevent oxidation of the cut portion of the cutting master 10 from being generated, thereby preventing the processed surface from being oxidized. Long-term processing becomes possible.
[0089]
Next, a fine pattern processing apparatus according to a second embodiment of the present invention will be described. FIG. 10 is an enlarged view showing a main part of a fine pattern processing apparatus 64 according to a second embodiment of the present invention, and specifically shows a feed mechanism 70 for feeding the cutting master 10 during cutting. .
[0090]
The feed mechanism 70 is disposed on a table 68, and roughly includes a sub-table 72, a feed base 74, a hydraulic cylinder 78, and the like. The cutting tool 40 is fixed to a chuck 66 disposed above the feed mechanism 70.
[0091]
Then, the cutting master 10 is fed by the feed mechanism 70 relative to the cutting tool 40 in the direction indicated by the arrow X in the drawing, whereby a fine pattern is formed on the upper surface of the cutting master 10. FIG. 10 shows a state in which the cutting tool 40 is at a position moved upward with respect to the cutting master 10.
[0092]
Hereinafter, each component of the feed mechanism 70 will be described.
[0093]
The sub-table 72 is configured to fix the cutting master 10 thereon by a fixing mechanism (not shown). The sub-table 72 is configured to be able to move in the direction of the arrow X above the feed table 74. Further, the feed table 74 is fixed to the table 68 by a fixture 75.
[0094]
The present embodiment is characterized in that a hydraulic cylinder 78 is used as means for driving the sub-table 72, and a hydrostatic guide surface 76 is provided as guide means for moving the sub-table 72 on the feed base 74. It is. Since the hydraulic cylinder 78 is configured to directly expand and contract the drive shaft 79 by the supplied hydraulic pressure and directly drive the sub-table 72, vibration generated by the hydraulic cylinder 78 is reduced as compared with the conventional case using a ball screw mechanism. be able to.
[0095]
The hydraulic static pressure guide surface 76 has a pair of inclined surfaces, and has a V-shaped groove shape in which the lower portion has an angle of approximately 90 degrees. Further, a triangular projection having an inclined surface corresponding to the hydraulic static pressure guide surface 76 is formed on the sub-table 72, and the triangular projection engages with and is guided by the V-shaped groove shape. The sub-table 72 moves on the feed table 74.
[0096]
Further, an oil film is provided on each inclined surface of the hydraulic static pressure guide surface 76, so that the sub-table 72 is configured to receive the feed table 74 with the hydraulic static pressure. Therefore, even when the hydraulic static pressure guide surface 76 is provided, generation of vibration when the sub-table 72 moves on the feed plate 74 is different from the configuration in which the conventionally used sub-table is guided by the roller guide surface. Can be suppressed.
[0097]
As described above, according to the present embodiment, it is possible to suppress the occurrence of vibration when the sub-table 72 moves on the feed base 74, and thus the surface of the cutting master 10 is caused by the vibration during the cutting of the fine pattern. The occurrence of streaks can be prevented. Next, a fine pattern processing apparatus according to a third embodiment of the present invention will be described. FIGS. 11 and 12 are enlarged views of a main part of a fine pattern processing apparatus according to a third embodiment of the present invention. Specifically, the vicinity of a cutting tool 40 is enlarged.
[0098]
In this embodiment, the cutting position of the cutting tool 40 is determined using the CCD camera 80 (imaging means). Further, a prism 82 (byte image superimposing means) is provided between the CCD camera 80 and the cutting master 10, so that the state on the cutting master 10 is imaged by the CCD camera 80 via the prism 82. It has become.
[0099]
The prism 82 is disposed so as to be substantially parallel to the cutting tool 40, and a fixed focus lens 86 is provided on an incident surface 84 formed at a lower end thereof. Image light indicating the state on the cutting master 10 enters the prism 82 from the incident surface 84 via the fixed focus lens 86, passes through the prism 82, and enters the CCD camera 80. The fixed focal length lens 86 has a predetermined focal length.
[0100]
A reflecting surface 88 is formed at the lower end of the prism 82 so as to be continuous with the incident surface 84. The reflecting surface 88 is a surface in which the prism 82 is inclined by 45 ° with respect to the optical axis of the image light, and functions as a half mirror by forming a metal thin film on the surface, for example. The reflection surface 88 is provided so that the image of the cutting tool 40 can be captured by the CCD camera 80.
[0101]
Therefore, in the present embodiment, the CCD camera 80 takes an image of the upper surface of the cutting master 10 and the cutting tool 40 in three different modes. That is, in FIG. 12, an image formed by light passing through the fixed focus lens 86 indicated by an arrow a, an image formed by light passing through an incident surface 84 indicated by an arrow b, and the cutting tool 40 reflected by a reflecting surface 88 indicated by an arrow c. It is an image shown.
[0102]
FIG. 13 shows an image screen 94 imaged by the CCD camera 80 in this embodiment. In the example shown in the figure, the upper part of the imaging screen 94 is the reflection surface area, and the side surface of the cutting tool 40 is displayed. The lower part of the imaging screen 94 is the incident surface area, and the state of the surface of the cutting master 10 is displayed.
[0103]
Further, a lens enlargement area by the fixed focus lens 86 is formed inside the incident surface area, and the state of the surface of the cutting master 10 is displayed in an enlarged state in this lens enlargement area. The striped pattern in the incident surface area shown in FIG. 13 is obtained by capturing the fine pattern 11a.
[0104]
In this embodiment, the prism 82 can be moved in the horizontal direction and the vertical direction by operating the prism positioning dial 90, and the cutting tool 40 is moved vertically with respect to the prism 82 by the cutting tool moving device 92. It is configured to be movable. Note that the cutting tool 40 is configured to move integrally with the prism 82 when the prism 82 is moved in the horizontal direction.
[0105]
In the micropattern processing apparatus having the above-described configuration, in order to position the tip portion 40a of the cutting tool 40 at a predetermined cutting start position, the cutting tool 40 is moved to the same height as the height of the incident surface 84 using the cutting tool moving device 92. The height of the tip portion 40a is determined, and the vertical position is adjusted so that the focal point of the fixed focus lens 86 is positioned on the surface of the cutting master 10.
[0106]
Subsequently, the cutting tool 40 is moved in the horizontal direction together with the prism 82 while looking at the imaging screen 94, and positioning processing is performed so that the tip portion 40a of the cutting tool 40 matches the cutting start position at which the cutting processing is to be started. At this time, since the cutting tool 40 and the cutting master 10 are displayed on the same imaging screen 94, this positioning process can be easily performed.
[0107]
When the positioning between the tip portion 40a of the cutting tool 40 and the cutting start position is completed, the cutting tool 40 is subsequently moved down by the focal length of the fixed focus lens 86, whereby the cutting tool 40 is moved to the cutting start position with high precision. (That is, a state where cutting can be started).
[0108]
【The invention's effect】
As described above, according to the present invention, it is possible to form a large number of nests from the same transfer mold, so that all the nests formed have the same shape and there is no machining error. When used to form an optical component, the reproducibility of optical characteristics can be improved.
[0109]
Further, when a plurality of nests are mounted on a mold to take a large number of resin-formed products, the flow balance of the resin in the cavity of the mold is made uniform, so that it is not necessary to adjust the gate balance. Further, in small-scale molding such as trial production, a thin electroformed plate can be manufactured in a short turn.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining a method of manufacturing a mold and a method of molding an optical component according to a first embodiment of the present invention.
FIG. 2 is a view for explaining a method of manufacturing a mold and a method of molding an optical component according to a second embodiment of the present invention.
FIG. 3 is a view for explaining a fine pattern processing method according to the first embodiment of the present invention.
FIG. 4 is a view for explaining a fine pattern processing method according to a second embodiment of the present invention.
FIG. 5 is a view for explaining a fine pattern processing method according to a third embodiment of the present invention.
FIG. 6 is a diagram for explaining an effect when a fine pattern processing method according to a fourth embodiment of the present invention is performed.
FIG. 7 is a view for explaining an effect when a fine pattern processing method according to a fifth embodiment of the present invention is performed (part 1).
FIG. 8 is a view for explaining an effect when a fine pattern processing method according to a fifth embodiment of the present invention is performed (part 2).
FIG. 9 is a view for explaining a fine pattern processing apparatus according to the first embodiment of the present invention.
FIG. 10 is a view for explaining a fine pattern processing apparatus according to a second embodiment of the present invention.
FIG. 11 is a view for explaining a fine pattern processing apparatus according to a third embodiment of the present invention.
FIG. 12 is a view for explaining a fine pattern processing apparatus according to a third embodiment of the present invention, and is a view showing a configuration near a prism arrangement position.
FIG. 13 is a diagram for describing a fine pattern processing apparatus according to a third embodiment of the present invention, and is a diagram illustrating an example of a CCD imaging screen.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Cutting master 11 Fine pattern 15 Inversion pattern 16 Transfer mold 20, 34 Insert 22 Mold 26 Optical component 28 Acrylic plate 32 Transfer master 36 Suction pipe 40, 40A-40C Tool bit 42 Cut piece 44 Cutting oil 46 Cutting edge 48 Cutting part 50 Blade wear part 52 Smooth surface 58 Rust prevention oil 60 Cutting oil supply nozzle 62 Rust prevention oil supply nozzle 64 Fine pattern processing device 68 Table 70 Feed mechanism 72 Subtable unit 74 Feed table 76 Hydraulic static pressure guide surface 78 Hydraulic cylinder 80 CCD camera 82 prism 84 incident surface 86 fixed focus lens 88 reflecting surface 90 prism positioning dial 92 byte moving mechanism 94 imaging screen

Claims (1)

In a method of manufacturing a mold having a nest on which a fine pattern is formed,
When manufacturing the nest,
First, a cutting master on which a fine pattern is formed in advance is formed,
Subsequently, a transfer master is formed from the cutting master by hot pressing,
Subsequently, a nest is formed from the transfer master by using an electroforming method.

Images