JP2009113252A - Minute molding die material consisting of vitreous carbon material, method for manufacturing the same and minute molding die made with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a minute molding die material consisting of a vitreous carbon material, from which a minute molding die for micro/nano-level precision processing is formed without applying a fluorine-based coating material to the minute molding die or without coating the minute molding die with DLC (diamond-like carbon) or the like and which has excellent mold releasability. <P>SOLUTION: The vitreous carbon material is heat-treated at 2,100-3,000°C to obtain the minute molding die material having a self-lubricating/releasing property. The minute molding die is formed from the obtained minute molding die material. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a material for a fine mold in which fine molding has been performed so that the size of the concavo-convex portion is about several nanometers to several hundreds of micrometers, a manufacturing method thereof, and a fine mold using the same.

  For mobile phone parts and electronic device parts, there is a need for a fine mold that allows fine processing with a concavo-convex dimension of several nanometers to several hundreds of micrometers. Few products have reached the practical level in terms of production methods and mold release problems when creating transfer products. In particular, the problem of mold release processing technology has become a very important issue. However, this means that the molded product (transfer product) produced with a fine mold is extracted (released). The smaller the scale, the more particularly the nano-level micro mold, etc. This is because it is often difficult to release.

  Conventionally, as a transfer material of a fine mold having a line width and a depth of several tens of μm to several nm, silicon rubber such as thermosetting resin, ultraviolet curable resin, and the like are known. In these cases, There is often a situation in which the fine mold and the transfer product are in close contact with each other and the transfer product cannot be removed (transferred) cleanly from the fine mold.

  In order to solve such problems, a method of applying a fluorine-based coating material to a mold is usually employed as a pretreatment for mold release. However, in this method, recoating of the coating material is required periodically, and the application requires skill and a lot of labor.

  As another solution, in recent years, a method of coating (coating) a lubricant such as DLC (diamond-like carbon) on the surface of a metal mold has been attracting attention, but the size of the uneven portion is about several nm to several hundred μm. It was very difficult to coat the surface of a certain fine mold with a uniform thickness, and there was a problem that an error of the fine mold due to the film thickness could not be ignored. For example, a normal DLC coating has a film thickness of about 1 to 3 μm, and it is practically impossible to coat a fine mold with irregularities on the nano level using this.

  For this reason, it is particularly necessary to apply a fluorine-based coating material to a fine mold, and to apply a DLC coating or the like that causes an error in mold accuracy, as in the conventional case. Realization of a new technical means for enabling the transfer of the irregularities on the surface has been desired.

  On the other hand, in such a situation, an attempt has been made to use a glassy carbon material for a smaller mold. For example, it has been proposed to improve mold releasability and durability by using glassy carbon for part or all of a mold (Patent Documents 1-7). In Patent Document 1, a method using all glassy carbon in the mold is used, and in Patent Document 2-3, a method of increasing the mold releasability by using the whole mold or surface glassy carbon is disclosed in Patent Document 4- No. 6 discloses a method for improving mold releasability and durability by replacing a part of the mold with glassy carbon. Patent Document 7 shows application of filling molding to a mold.

However, although attention has been paid to the application of glassy carbon materials to molds, the technical study has not been deepened and expanded to nano-scale precision fine molds, and there are many unexplored practical applications. There are still challenges. In fact, it is still not possible to use it in nano-scale precision fine molds.
JP 2001-335334 A JP-A-10-337734 Japanese Patent Laid-Open No. 10-296741 JP 09-188535 A Japanese Patent Laid-Open No. 08-239227 JP 2005-112672 A JP 2004-034194 A

  As described above, the nano-level fine mold and its transfer usually require re-application of the coating material to the mold, and the application requires skill and a lot of labor. In addition, the method of coating a metal mold with a lubricant such as DLC has attracted attention, but it is very difficult to coat with a uniform thickness along a micro-mold with micro / nano level irregularities. In addition, there is a drawback that an error of the fine mold due to the film thickness cannot be ignored.

  Therefore, the present invention eliminates the problems of the prior art as described above, and does not perform conventional coating of a fluorine-based coating material or formation of a coating such as DLC, and the mold release property, durability, etc. It is an object of the present invention to provide a new technical means for making it possible to apply a glassy carbon material, which has attracted attention in this respect, to a micro-molding die for micro- and nano-level precision processing.

  The present invention has the following features to solve the above-mentioned problems.

  First: a fine mold material made of a glassy carbon material, and an R value represented by the following formula in Raman measurement (wavelength 514.5 nm) on the surface;

Is a fine mold material having a value of 1.5 or less.

  Second: The above fine mold material having an R value of 1.3 or less.

  Third: A fine mold material made of a glassy carbon material, using a diamond pin (with a radius of curvature of 0.2 mm and a tip angle of 90 °) in the atmosphere, at a constant sliding speed (20 mm / min), 24. A fine mold material having a surface friction coefficient of 0.1 or less when moved by 0.8 mm only once in a fixed direction under a load of 5 mN.

  Fourth: The above fine mold material having a surface friction coefficient of 0.07 or less.

  Fifth: A fine mold material made of a glassy carbon material and having a surface contact angle of 85 ° or more.

  Sixth: The above fine mold material having a contact angle of 90 ° or more.

  Seventh: A method for forming a fine mold material according to any one of the first to sixth methods, wherein the glassy carbon material is heat-treated within a temperature range of 2100 ° C. to 3000 ° C. .

  Eighth: The method for forming a fine mold material described above, wherein the heat treatment is performed within a temperature range of 2250 ° C to 3000 ° C.

  Ninth: A fine mold in which the fine mold material according to any one of the first to sixth is used as a substrate, and a processing groove is formed on the surface of the substrate, and a processing dimension of the processing groove Is in the range of 50 μm to 1 nm for each of the line width and depth.

  Tenth: The fine mold described above, wherein the processing dimension of the processing groove is in the range of 1 μm to 2 nm.

  According to the present invention, as a fine mold material, glassy carbon is heat-treated at 2100 ° C. or higher to exhibit self-lubricating releasability. When a fine mold is produced using this, the transferred product can be prevented from coming into close contact with the fine mold, and the transferred product can be released. In the present invention, since film formation is not performed on the fine mold, a fine mold (with lubricity) having a line width of several tens of nanometers can be manufactured without considering the error in line width due to film formation. Since the surface of the fine mold is not deformed and has a self-lubricating mold release property having a mold release property, it is possible to enhance the function of the fine mold die, which is extremely useful industrially.

  As described above, the fine mold material of the present invention is specified as having the following characteristics.

  <A> The R value in the Raman measurement (wavelength 514.5 nm) on the surface is 1.5 or less, more preferably 1.3 or less.

  <B> The surface friction coefficient is 0.1 or less, more preferably 0.07 or less.

  <C> The contact angle of the surface is 85 ° or more, more preferably 90 ° or more.

  Here, the R value and the surface friction coefficient follow the above definitions. By using the fine mold material having such characteristics, the self-lubricating mold releasability is retained in the fine mold for the micro / nano level precision machining fine mold.

  Here, the term “self-lubricating releasability” means, as in the past, external addition means such as a lubricant such as a fluorine-based coating material, a releasing agent, a lubricating film such as a DLC film, and a releasing film. This means that the surface of the fine mold itself has a smooth release performance without using any of the above. This performance means that it is realized in micro- and nano-level precision dimensions, more specifically, in a processing dimension of 50 μm or less, and further 1 μm or less.

  Actually, for example, such a fine mold material of the present invention in which a processing dimension in the range of 1 μm to 2 nm is realized for each of the line width and depth, and the fine mold using the same is formed. As a method, the glassy carbon agent is preferably heat-treated at 2100 ° C to 3000 ° C, more preferably heat-treated at 2250 ° C or higher.

  For glassy carbon materials, unlike the graphite with a layered microstructure, the micro hexagonal network aggregates are not oriented, the growth of crystallites due to bonding is inhibited, and graphitization does not proceed. Known as a thing. It is also called non-graphitizable carbon.

For the fine mold material after the heat treatment, a processing groove is formed on the surface thereof by means such as FIB (focused ion beam) to obtain a required fine mold structure.
Further, in the present invention, even when the heat treatment is performed at the above heat treatment temperature after forming the groove for processing, the fine mold structure can be formed as in the case of forming the groove after the heat treatment.

  Then, an Example is shown below and it demonstrates in detail.

  Of course, the invention is not limited by the following examples.

  Glassy carbon was produced as follows. A furfuryl alcohol initial polymer and a curing agent mainly composed of p-toluenesulfonic acid were used as starting materials. About 120 g of furfuryl alcohol was added with about 0.3 g (about 0.3 wt.%) Of the curing agent, and stirring and ultrasonic irradiation at 30 to 40 Hz were performed using a horn type ultrasonic irradiation machine. After the sample temperature reached 50 ° C., stirring and ultrasonic irradiation were performed for 75 minutes. This ultrasonic irradiation is performed for the removal of pores and uniform mixing.

  After completion of stirring and ultrasonic irradiation, the mixture was poured into a square container made of polyethylene and allowed to stand in the atmosphere for 24 hours at room temperature. After standing, it was treated in air at 50 ° C. for 48 hours using a dryer. The sample was then treated in air at 160 ° C. for 6 hours using a dryer to produce a furan resin.

  The obtained furan resin was carbonized in an Ar atmosphere at 1000 ° C. for 30 minutes to produce furan resin charcoal. The obtained furan resin charcoal was subjected to high temperature treatment at 1200, 1500, 2000 and 3000 ° C. for 30 minutes in an Ar atmosphere, respectively, to prepare a furan resin charcoal as a specimen.

  In the heating furnace, the glassy carbon material was heat-treated within a range of 1000 ° C to 3000 ° C. The friction coefficient and contact angle of the sample surface after the heat treatment were measured. 1 and 2 show the results. The coefficient of friction is measured as follows.

  That is, the friction test was performed using a Bauden-Leven type tester HEIDON 18LFW manufactured by Shinto Kagaku Co., Ltd. A diamond pin (with a radius of curvature of 0.2 mm and a tip angle of 90 °) was used as the friction material for the GLC.

  The test conditions were a constant sliding speed (20 mm / min) in the atmosphere, a load of 24.5 mN, and a friction coefficient was measured when each sample was moved 0.8 mm once in a fixed direction. A base surface of pyrolytic graphite (PG) was also measured as a reference sample.

  Before the test, the sample and the diamond pin were washed with toluene and acetone for 10 minutes each using an ultrasonic cleaner, and then sufficiently dried and subjected to the test.

  From FIG. 1, it can be seen that the coefficient of friction is reliably 0.1 or less at a treatment temperature of about 2000 ° C. or more, and further 2100 ° C. or more, and 0.07 or less at 2250 ° C. or more. It has been confirmed that when the coefficient of friction is 0.1 or less, more preferably 0.07 or less, excellent self-lubricating release properties can be realized as a micro- and nano-level precision processing fine mold. Further, the contact angle in the present invention is an angle of contact between the surface of the fine mold (base material) and, for example, a dropped water droplet, and the contact angle is 85 ° or more, and more preferably 90 ° or more. Preferably, the heat processing temperature for it is confirmed from FIG.

FIG. 3 shows the temperature dependence of Raman data (wavelength 514.5 nm) of glassy carbon and the R value obtained therefrom = I _D / I _G (I _D : Raman intensity at 1360 cm ⁻¹ band, I _G : 1580 cm band) Raman intensity at ^-1 )
This shows the temperature dependence of. The following results are shown.

(A) temperature treatment dependence of R value = I D _/ I _G according to the temperature treatment dependent (b) Raman spectroscopy by Raman spectroscopy of glassy carbon fracture surface Therefore, the fine mold material after heat treatment at 2250 ° C. On the other hand, fine groove processing by FIB was performed, and a cross-shaped fine mold having a width of 400 nm and a depth of 200 nm as shown in the SEM photograph of FIG. 4 was produced.

  Silicon rubber was used as a transfer product, poured into a fine mold, and cured by heating at about 80 ° C. Then, it was cooled, the silicon rubber was peeled from the substrate, and observed with an optical microscope and a scanning electron microscope (SEM) to confirm that the transfer was successful. FIG. 5 illustrates an SEM photograph of the transferred product that has been released from the mold.

Relation between friction coefficient of glassy carbon and processing temperature. Relationship between contact angle of glassy carbon and processing temperature. Glassy Temperature dependence and R value of Raman data carbon _{= I D / I G (I} D: Raman intensity of the band 1360cm ^-1, _{I G:} Raman intensity of the band 1580 cm ^-1) Temperature dependence of.

  (A) Temperature treatment dependence by Raman spectroscopy of the glassy carbon fracture surface.

(B) temperature treatment dependence of R value _{= I} D / I _G by Raman spectroscopy.
SEM photograph of the actually produced fine mold. SEM photograph of the transcript that was actually released from the fine mold.

Claims (10)

An R value represented by the following formula in a Raman measurement (wavelength 514.5 nm) on the surface, which is a fine mold material made of a glassy carbon material;
Is a fine mold material characterized in that it is 1.5 or less.   R value is 1.3 or less, The fine mold material of Claim 1 characterized by the above-mentioned.   A fine mold material made of a glassy carbon material, using a diamond pin (with a radius of curvature of 0.2 mm and a tip angle of 90 °), with a constant sliding speed (20 mm / min) and a load of 24.5 mN in air. A fine molding die material having a surface friction coefficient of 0.1 or less when moved 0.8 mm only once in a certain direction below.   The fine mold material according to claim 3, wherein the surface friction coefficient is 0.07 or less.   A fine mold material comprising a glassy carbon material, wherein the surface contact angle is 85 ° or more.   The fine mold material according to claim 5, wherein the contact angle is 90 ° or more.   The method for forming a fine mold material according to any one of claims 1 to 6, wherein the glassy carbon material is heat-treated within a temperature range of 2100 ° C to 3000 ° C. Forming method.   The method for forming a fine mold material according to claim 7, wherein the heat treatment is performed within a temperature range of 2250 ° C to 3000 ° C.   A fine molding die in which the fine mold material according to any one of claims 1 to 6 is used as a substrate, and a processing groove is formed on a surface of the substrate, and the processing dimension of the processing groove is a line width. And a depth within a range of 50 μm to 1 nm for each of the depths.   10. The fine mold according to claim 9, wherein a processing dimension of the processing groove portion is in a range of 1 μm to 2 nm for each of the line width and the depth.