JPH11314927A - Production of article having rough surface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a producing method of an article having a fine rugged surface coated with a film which has high heat resistance, which produces no cracks and which does not peel from the base body. SOLUTION: A solgel material is disposed in a film state as adhered between a base body and a molding die, and then heated to form a gelated film having the reversal shape of the surface of the molding die on the base body surface. In this producing method of an article having a rugged surface, the solgel material contains (A) a silane compd. expressed by formula I of2 SiX2 (R is an alkyl group, X is an alkoxyl group or halogen atom) and (B) a compd. expressed by R'SIX'3 (R' is an aryl group or aryl substituent, X' is an alkoxyl group or halogen atom).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an article having fine irregularities on its surface, particularly to a micro-optical element and an information recording medium substrate, a method for producing the same, and a preparation composition therefor.

[0002]

2. Description of the Related Art CD-ROMs, other information recording media,
Optical components such as a flat plate microlens (a lens array in which a large number of minute lenses are arranged in parallel on a flat plate), a Fresnel lens, and a diffraction grating element need to have minute irregularities on the surface. The minute irregularities on the surface function as pits or tracking guides in the information recording medium,
In an optical component, it functions as a microlens or a diffraction grating by focusing or diffusing light.

In order to form these irregularities on the surface,
There is known a method in which an ultraviolet-curing resin is uniformly spread on a substrate, and the resin is irradiated with ultraviolet rays while being pressed by a molding die having an uneven portion (JP-A-63-49702).

Japanese Patent Application Laid-Open No. 62-102445 discloses a so-called sol-gel in which a solution containing silicon alkoxide is applied to a glass substrate and heated while pressing a mold having irregularities to form the irregularities. Production methods are described. Japanese Patent Application Laid-Open No. Hei 6-242303 describes a method of forming a plurality of layers on a substrate when a film having a thickness of several μm or more is formed by using a sol-gel method. In this case, the components of each layer were developed with a solution or sol, heated under pressure while pressing with a mold, and then, on the completely solidified layer, the solution or sol was further poured to form the upper layer. .

[0005]

However, the above-mentioned prior art has the following problems. First, an ultraviolet curable resin has low heat resistance, and decomposes and yellows at 250 ° C. or higher. Therefore, a substrate having an uneven portion made of an ultraviolet curable resin cannot be heated by soldering or the like, and it is difficult to mount the substrate on an apparatus or the like.

On the other hand, the uneven portion of silicon alkoxide formed by the sol-gel method has high heat resistance and can be soldered. However, the sol-gel method has a problem that a thick film cannot be formed. When a silicon alkoxide layer of several tens of μm is actually formed by the sol-gel method, minute cracks (hereinafter, referred to as cracks) are generated on the surface. This is because when the silicon alkoxide solution gels and solidifies, the degree of progress of the polycondensation reaction between the surface and the inside of this layer is different, so that a large stress is generated on the surface. Further, the layer may be separated from the substrate due to the stress.

In addition, an organopolysiloxane layer having a concavo-convex shape having a thickness of several tens of μm can be formed by a method of sequentially forming the organopolysiloxane layer to form a multilayer. However, since the manufacturing process becomes longer, it causes a cost increase, and since the lower layer is completely cured, the next layer is injected, so that unnecessary air easily enters between the mold and the solution or sol, The dimensional accuracy of the irregularities was not high.

The present invention has been made by paying attention to such problems existing in the prior art. The purpose is to have high heat resistance, and dozens to thousands μm in a single layer film.
It is an object of the present invention to provide a method for manufacturing an article having a fine uneven surface with high dimensional accuracy, in which no crack is generated on the surface even if the layer has a thickness of m and the layer does not peel off from the substrate. It is another object of the present invention to provide a composition for forming the film. Yet another object of the present invention is to provide an article having irregularities produced by the method of the present invention.

[0009]

SUMMARY OF THE INVENTION According to the present invention, the present invention and advantages include, first, a sol-gel material disposed in a film-like manner in intimate contact between a substrate and a mold, and then heated. In the method for producing an article having an uneven surface, in which a base material surface is coated with a gelling film having a surface having a shape inverted from the surface shape of the mold, the sol-gel material is represented by the following formula (1): R ₂ SiX ₂ ... (1) wherein R is an alkyl group, and X is an alkoxyl group or a halogen atom; and (B) a silane compound represented by the following formula (2): R′SiX ′ ₃ .. (2) wherein R ′ is a substituted or unsubstituted aryl group;
X 'is an alkoxyl group or a halogen atom, which is achieved by a method for producing an article having an uneven surface characterized by containing a silane compound represented by the following formula:

According to the present invention, the present invention and advantages are as follows. Secondly, an organopolysiloxane film having irregularities on the surface of an article substrate is formed with a thickness of 1 μm to 1 mm, and an alkyl group is contained in the film. This is achieved by an article having a textured surface comprising 5-25% and 5-40% by weight (e.g., a methyl group) and an aryl group (e.g., a phenyl group), respectively.

Finally, according to the present invention, (A) 1 mol of a dialkyldialkoxysilane, (B) 0.2 to 4 mol of a trialkoxysilane containing an aryl group or a substituted aryl group, (C) alcohol (mol) (Expressed as a ratio) Component (A) + 0.3 to 3 times the mole of component (B) (D) Acid catalyst (expressed as a molar ratio) (A) Component + 3 to 20 times the mole of component (B) (E 2.) Water (expressed in terms of molar ratio) A composition for forming a film for producing an article having an uneven surface, comprising 2 to 20 times the molar amount of the component (A) + the component (B), is also provided.

In the present invention, the raw material of the sol-gel material is
Both the silane compound represented by the above formula (1) and the silane compound (A) represented by the above formula (2) are contained.

In the above formula (1), R is an alkyl group and X is an alkoxyl group or a halogen atom.
The alkyl group for R may be linear or branched, and is preferably an alkyl group having 1 to 3 carbon atoms. The alkoxyl group of X may be linear or branched, and is preferably an alkoxyalkyl group having 1 to 4 carbon atoms. Examples of the halogen atom for X include fluorine,
Chlorine and bromine can be mentioned.

The silane compound represented by the formula (1) includes, for example, dialkyldialkoxysilanes such as dimethyldiethoxysilane, dimethyldimethoxysilane, diethyldiethoxysilane and diethyldimethoxysilane; dimethyldichlorosilane, diethyldichlorosilane And the like can be enumerated as preferred.

In the above formula (2), R 'is a substituted or unsubstituted aryl group, and X' is an alkoxyl group or a halogen atom. As the unsubstituted aryl group, an aryl group having 6 to 13 carbon atoms such as phenyl, biphenyl, and naphthyl is preferable. Preferred examples of the substituent of the aryl group include an alkyl group having 1 to 3 carbon atoms or a halogen atom. Preferred examples of the aryl group substituted with such a substituent include a tolyl group, a xylyl group, and a chlorophenyl group. Further, as the alkoxyl group and the halogen atom of X ′, formula (1)
And the same as those exemplified for X.

Examples of the silane compound represented by the above formula (2) include phenyltriethoxysilane, phenyltrimethoxysilane, and triethoxy having a substituted phenyl group in which a part of hydrogen of the phenyl group is substituted with a halogen atom, for example, a chlorine atom. Silane, trialkoxysilane having a phenyl group or a substituted phenyl group such as trimethoxysilane having the same substituted phenyl group as described above; phenyltrichlorosilane, substituted phenyl in which a part of hydrogen of the phenyl group is substituted by a halogen atom, for example, a chlorine atom Trichlorosilane having a group; tolyltrimethoxysilane, tolyltriethoxysilane; tolyltrichlorosilane; xylyltrimethoxysilane, xylyltriethoxysilane; xylyltrichlorosilane; biphenyltrimethoxysilane, biphenyltriethoxy Silane; biphenyl trichlorosilane; and the like.

When both methoxysilane and ethoxysilane alkoxysilane are used as the component (A) represented by the above formula (1) and the component (B) represented by the above formula (2), the hydrolysis reaction The resulting alcohol is preferable because it easily evaporates. (A) of raw material of sol-gel material
Preferred combinations of the component and the component (B) include dimethyldialkoxysilane and phenyltrialkoxysilane.

In the present invention, the components (A) and (B) are used as a raw material of the sol-gel material, and an alkyl group and an aryl group are contained in a film obtained by coating the components on a base material. Residue in large quantities. Since the alkyl group and the aryl group serve to reduce the brittleness of the film and impart elasticity to the film, it is possible to suppress the thermal stress generated inside the film, and therefore, the occurrence of cracks in the film and the film from the article substrate. Is prevented from peeling off.

The case where the component (A) is a dialkyldialkoxysilane and the component (B) is a trialkoxysilane containing an aryl group or a substituted aryl group will be described below.

The film structure of the present invention is characterized in that the dialkoxysilane and the trialkoxysilane are mixed so that the end of the linear dialkoxysilane extended in a fibrous form is three-dimensionally continued. As a result, it is presumed that a space is generated in the three-dimensional skeleton, which gives elasticity to the film, reduces brittleness of the film, and can form a thick film.

Here, the meaning that the film according to the present invention contains an aryl group or a substituted aryl group means that these groups are more fragile than the other organic groups in the oxide skeleton structure in the film. It has sufficient bulkiness to give elasticity while suppressing, and also has high temperature stability by having a conjugated system compared to other organic groups.
For example, in a film containing cyclohexyl trialkoxysilane and dialkyldialkoxysilane in which an aryl group or a substituted aryl group is replaced by a cyclohexyl group having no conjugated system, the film discolors at 2 to 300 ° C., and cracks occur.

The raw material of the sol-gel material preferably contains the component (B) in a ratio of 0.2 to 4 mol per 1 mol of the component (A). When the amount of the component (B) is less than 0.2 mol, the film is hardly cured, and most of the components are volatilized at the time of final heating (at the time of firing), so that it is difficult to form a film finally.
When the amount of the component (B) is more than 4 mol, the flexibility of the film is impaired, and a film having a thickness of 20 μm or more is liable to be cracked at the time of final heating or cooling after the final heating. More preferably, the component (B) contains both components in a ratio of 0.4 to 1.0 mol per 1 mol of the component (A).

If an alkoxysilane having an organic group other than the above, for example, a mixture of dimethyldimethoxysilane and vinyltriethoxysilane is used as a raw material of the sol-gel material, the resulting film undergoes thermal decomposition at 300 ° C. or lower, Heat resistance is significantly reduced. Further, for example, when only tetraalkoxysilane is used as a raw material, when only alkyltrialkoxysilane is used as a raw material, and when a mixture of dialkyldialkoxysilane and alkyltrialkoxysilane is used as a raw material, When the film stress after the final heating increases and a thick film having a thickness of 20 μm or more is formed, cracks occur.

As a raw material of the sol-gel material in the present invention, an alcohol is added as a solvent to a mixed solution of the component (A) and the component (B). As the alcohol to be added, a lower alcohol having 1 to 4 carbon atoms, particularly, methanol or ethanol having a small boiling point is suitably used. The reason is that after the hydrolysis, the alcohol can be quickly removed from the solution by a heat treatment at a relatively low temperature. The amount of the alcohol to be added is preferably from 0.3 to 3 times, more preferably from 0.5 to 1.5 times, the molar amount of the total of the components (A) and (B).

A catalyst for hydrolyzing the alkoxysilane is added to this solution. As the catalyst, an acid catalyst is preferably used. For the acid catalyst, formic acid, hydrochloric acid, nitric acid,
Preferably, at least one acid catalyst of sulfuric acid is used in the form of an aqueous solution. The amount of the acid catalyst to be added is represented by a molar ratio and is 3 to 20 with respect to the total of the components (A) and (B).
The number is preferably 5 times, more preferably 5 to 15 times. Further, it is preferable to add water at a stoichiometric ratio necessary for hydrolysis. If the added amount of water is smaller than the stoichiometric ratio, unreacted alkoxysilane tends to volatilize during heat treatment for gelation. Usually, the amount of water added is 1.1 to 3 times the required stoichiometric ratio, including the water of the catalyst aqueous solution, and is expressed in terms of a molar ratio with respect to the sum of the components A) and (B). It is preferably 2 to 20 times, more preferably 4 to 10 times.

In the present invention, a solution composed of the components (A) and (B), the alcohol solvent, water and the catalyst, which are the raw materials of the sol-gel material, is held, for example, at room temperature for 90 to 120 minutes with stirring. It is prepared by hydrolyzing both alkoxysilanes. Thereafter, the temperature is further maintained at room temperature to 140 ° C., more preferably 70 to 100 ° C., for 6 to 30 hours to advance the dehydration / polycondensation reaction, and the solvent in the solution,
It is preferable to vaporize and evaporate water and alcohol and water which are dehydration / polycondensation reaction products. as a result,
The weight and volume of the solution is reduced to 25-35% by weight and volume% of the original formulation. Accordingly, shrinkage after film formation can be suppressed as much as possible to prevent cracking of the film, and a cured film can be formed without generating bubbles in the film at the time of final heating. If the dehydration / polycondensation reaction proceeds too much, the viscosity of the solution becomes too high, and it is difficult to coat the surface of the mold or the substrate. Conversely, if the method of conducting the dehydration / polycondensation reaction is insufficient, generation of bubbles in the film at the time of final heating cannot be prevented. It is preferred that the viscosity of the solution is adjusted to how to proceed by Ri dehydration and polycondensation reactions to be selected temperature to be less than 10 ³ poise, the retention time.

In the present invention, a part or all of the alkoxyl group of the tetraalkoxysilane, alkyltrialkoxysilane or alkylhydrogendialkoxysilane or tetraalkoxysilane is newly added to the solution after the dehydration / polycondensation reaction. Halogen, for example, halogenated silane substituted with chlorine, halogenated silane in which part or all of the alkoxyl group of the alkyl trialkoxysilane is substituted with halogen, for example, chlorine, or alkoxyl of the alkyl hydrogen dialkoxysilane A halogenated silane in which part or all of the group is substituted with a halogen, for example, chlorine, is used in a molar ratio of 10% or less, preferably 0.001 to 10%, based on the total number of moles of the components (A) and (B). , More preferably 0.001 to 0.
1% and again from room temperature to 140 ° C., preferably 70 ° C.
It is preferable to keep the temperature at 100100 ° C. for 6 to 30 hours. By the above addition, the terminal of the oligomer having elasticity can be activated, and the above solution becomes a liquid that is more easily gelled. Can be lower. As a result, it is possible to lower the heating temperature and shorten the heating time for curing the film having the uneven surface formed by the molding die, so that the work can be performed efficiently and the life of the molding die is extended. In addition, the dimensional deviation in the substrate surface direction between the irregularities on the surface of the mold and the irregularities on the surface of the final film coated on the substrate becomes further extremely small. The above-mentioned alkoxysilane to be added is 10
%, The obtained film tends to crack.

The above alkyl hydrogen dialkoxy silane is represented by the following formula: R ¹ HSi (OR ² ) ₂ wherein R ¹ is an alkyl group, preferably a methyl group or an ethyl group, and R ² is an alkyl group, preferably Is preferably an alkyl group having 1 to 4 carbon atoms.

Before proceeding with the dehydration / polycondensation reaction in the solution obtained by hydrolyzing both alkoxysilanes while holding the mixture with stirring, the tetraalkoxysilane, the alkyltrialkoxysilane or the alkylhydrogen It is preferable to add an alkoxysilane or the like in a molar ratio of 10% or less, preferably 0.001 to 10%, based on the total number of moles of the components (A) and (B). In addition, the dimensional deviation in the substrate surface direction between the irregularities on the surface of the mold and the irregularities on the surface of the film coated on the substrate becomes extremely small. When the hydrolysis reaction and the dehydration / polycondensation reaction are continuously performed at room temperature, the addition of the alkoxysilane is carried out to some extent from the time after the completion of the stirring of the hydrolysis until the time when the oligomer is formed. Then you can always.

Formamide can be added as a polymerization catalyst to the solution after the dehydration / polycondensation reaction.
Formamide has a high boiling point of 210 ° C and works effectively without vaporization even during high-temperature heating for film curing, and also acts as a dehydration catalyst, which can increase the reactivity when curing liquids. It effectively acts on the final heating, suppresses the generation of bubbles due to dehydration, and forms a film without bubbles.
The preferred amount of formamide to be added is 1 to 10% by mole ratio based on the total number of moles of the above components (A) and (B).

The sol-gel material obtained as described above is closely adhered between the article base material and the molding die, arranged in a film shape, and heated to form a surface having a shape obtained by inverting the surface shape of the molding die. An article having an uneven surface coated with a gel film having the following is produced. The following two methods can be typically given as a process for forming the fine uneven film.

In the first method (hereinafter, referred to as a mold pouring method), a liquid of a sol-gel material is poured into a mold, heated, brought into contact with the article substrate, and further heated to join the substrate and the molded film and release the mold. This is the final heating method. That is, the mold having the fine irregularities is kept horizontal, and a liquid sol-gel material having a viscosity of 10 ³ poise or less is poured onto the mold to fill the sol-gel material so as to fill the recesses of the mold. Instead of pouring, the mold may be immersed in a bath of the sol-gel material, or a method of applying a liquid of the sol-gel material to the surface of the mold with a brush may be used. In this state, the sol-gel material filled on the mold is kept at 140 to 180 ° C. for 20 to 120 minutes until the viscosity of the sol-gel material becomes 10 ⁴ to 10 ⁸ poise to advance the dehydration / polycondensation reaction.

Next, the base material is brought into close contact with the mold, and the sol-gel material is brought into contact with the surface of the base material so as not to form a gap therebetween.
The sol-gel material is kept at 180 ° C. for 10 to 120 minutes to substantially complete the dehydration / polycondensation reaction of the sol-gel material and to gel. Next, by peeling off the mold and releasing the mold, the polysiloxane film, which is a soft gelling film, having a concavo-convex shape obtained by inverting the concavo-convex shape of the mold, is bonded to the surface of the base material. Is formed. If the mold release is performed too early, the polysiloxane film is too soft and the surface irregularities are deformed by its own weight. Therefore, the above heating is performed until this deformation does not occur.

Then, this is finally heated at 180 to 350 ° C. for 10 to 150 minutes to polycondensate the residual silanol groups of the polysiloxane film and vaporize the water generated by the polycondensation, so that the film has a thickness. The volume shrinks slightly in the direction to form a dense film. In this way, an article having a concave-convex surface coated with a film having a surface having a shape inverted from the surface shape of the mold is obtained.

In the second molding method (hereinafter, referred to as a base material pouring method), when a liquid of a sol-gel material is directly poured onto a substrate surface and heated to make the liquid film plastic (the liquid has a viscosity of 10 ⁴ to 1).
0 pressing a mold to ⁸ when it is poise) to the membrane of the article substrate surface, a method of heating as is, after the transfer molding, and release the mold, carrying out final heating. That is, the surface of the article substrate to be coated is kept horizontal and the viscosity is 1
0 ³ widen the sol-gel material poise liquid into a membrane the sol-gel material so as to have a predetermined thickness poured onto the substrate on top of the substrate. In this state, 140 to 18 until the viscosity of the poured sol-gel material becomes 10 ⁴ to 10 ⁸ poise.
Hold at 0 ° C. for 20 to 120 minutes to advance the dehydration / polycondensation reaction. Then, a mold having minute irregularities is pressed onto the film-like sol-gel material to apply a pressure of 0.5 to 120 k.
The sol-gel material is almost completely dehydrated and polycondensed by holding at g / cm ^{2 at} a temperature of 160 ° C. to 350 ° C. for 60 seconds to 60 minutes to gel. Then, by peeling the mold, a polysiloxane film, which is a gelled film having an uneven shape obtained by inverting the uneven shape of the mold on the surface, is formed in a state of being bonded to the surface of the base material. Then, this is finally heated at, for example, 180 to 350 ° C. for 10 to 150 minutes to polycondense the residual silanol groups of the polysiloxane film and vaporize the water generated by the polycondensation, so that the film is slightly evaporated in the thickness direction. The volume shrinks to form a dense film. In this way, an article having a concave-convex surface coated with a film having a surface having a shape inverted from the surface shape of the mold is obtained.

The above-mentioned mold is, for example, precisely etching the surface of a glass substrate having a flat surface to obtain a desired shape.
For example, a concave shape is formed. Using this as a seed mold, a convex metal matrix can be produced by electroless and electrolytic plating methods. Also, using the concave mold as a matrix, a convex metal seed mold can be produced by the plating method, and a concave metal mold can be produced on the seed mold by the plating method. These convex or concave molds can be used as molds. In the above plating method, metals such as nickel and chromium are preferably used. Further, using the seed mold prepared by the above-described method, a resin mold can be produced from the ultraviolet curable resin by a 2P molding method, and this can be used as a mold.

The cross section of the polysiloxane film of the present invention has one or more circular arcs, elliptical arcs, or mountain shapes. Various functions can be imparted to the base material by changing the shape of the projection. For example, a function as a flat microlens array, a function as a grating, or a function as a prism array can be provided by changing the fine unevenness.

The thickness of the polysiloxane film (after final heating) is 1 μm to 1 m, expressed as the average height of the projections and depressions of the film.
m. When the film thickness is 20 μm or more, the ratio of the minimum value (the height of the surface of the concave portion of the film) to the maximum value (the height of the surface of the convex portion of the film) of the film thickness is 0.25 or more, ie, the minimum value / maximum value. ≧
0.25, prevention of separation between the substrate and the film, and
Desirable for preventing cracking of the film. When the ratio of the minimum value to the maximum value of the film thickness (minimum value / maximum value) is less than 0.25,
This is because, in the process of forming the film, the substrate and the film are likely to be separated at the interface where the film thickness is the minimum, and the film is likely to be cracked.

Thus, according to the present invention, 350
It has excellent heat resistance to withstand temperatures of 1 ° C., a film thickness of 1 μm to 1 mm, a refractive index of 1.50 to 1.54, which is close to the refractive index of general glass, and a single layer of organopolysiloxane having fine irregularities. One layer is formed on the article substrate. The organopolysiloxane constituting this film contains 5 to 25% by weight, preferably 15 to 22% by weight, of an alkyl group such as a methyl group and 5 to 40% by weight, preferably 26 to 37% by weight of an aryl group such as a phenyl group. ing. This film is rich in elasticity (less brittle), has high strength, and is unlikely to crack. In addition, no foaming during molding is observed inside the film, and excellent transferability with extremely high dimensional accuracy of the fine irregularities on the film surface can be realized. Specifically, for example, when the height is 2
When a large number of protrusions of 0 to 100 μm are formed, the variation in the height of the film surface protrusions is 1 μm or less. In addition, the deviation of the distance between the protrusions on the film surface from the mold is measured accuracy (0.2 μm).
It is as follows.

The article substrate used in the present invention may have any shape such as a flat plate, a curved plate, and a bar.
It is desirable that the amount of warpage of the substrate surface at 200 ° C. and 20 ° C. (the length of thermal deformation in the direction perpendicular to the surface per unit length in the surface direction of the substrate) is within ± 5 μm per cm. . If the amount of warpage exceeds this range, the substrate and the film may peel or crack at the interface during the film forming process. Therefore, it is preferable to select the material, dimensions and shape of the substrate.

The substrate preferably has a coefficient of linear expansion of 1.5 × 10 ⁻⁵ / ° C. or less. If the linear expansion coefficient of the substrate is more than 1.5 × 10 -5 ^/ ° C., if a plastics substrate having a high thermal expansion coefficient such as polypropylene (9~15x10 ^{-5 /} ℃), the organopolysiloxane film This is because, during the molding process, the base material and the film are separated at the interface or the film is cracked. Normal inorganic glass has a linear expansion coefficient of 1.5 × 10 ⁻⁵ / ° C. or less. Preferably, at least the surface of the substrate is an oxide. If the surface of the substrate in contact with the organopolysiloxane film is not an oxide, the adhesive strength decreases during the film forming process,
This is because, in some cases, the substrate and the film are separated at the interface. Examples of preferable base material include silicate glass,
Examples thereof include oxide glasses such as borate glass and phosphate glass, quartz, ceramics, metals, epoxy resins, and glass fiber reinforced polystyrene. The metal does not join the organopolysiloxane film as it is, but it can be used as a base material if the surface of the metal is treated in advance with an oxidizing agent.

When an object transparent to light of a desired wavelength, for example, light in the visible, ultraviolet, or infrared region is used as the substrate in the present invention, the article having the uneven surface of the present invention is A function as a transmission optical element such as a lens, a diffraction grating, and a prism can be exhibited. When a transparent or opaque material is used as the substrate, a metal (aluminum, silver, etc.) or a dielectric film (magnesium fluoride, titanium oxide, etc.) is formed on the organopolysiloxane film. It is suitable for use as a reflective optical element such as a reflective diffraction grating or a Fresnel reflector, a CD-ROM or other information recording medium.

[0043]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. The manufacturing method of the fine uneven article is generally performed by the following procedure. (1) Preparation of an organopolysiloxane solution → (2) Application and heat treatment of a solution to a mold or substrate → (3) Joining, heat treatment and release → (4) Final heating (firing).

[Preparation of Organopolysiloxane Solutions (Solutions A and B)] 0.1 mol of phenyltriethoxysilane and 0.15 mol of dimethyldiethoxysilane were placed in a beaker and stirred. 0.25 mol of ethanol was added to this solution, and the mixture was stirred. Formic acid was added to 1.75 mol (31.5 g) of water at a concentration of 0.15 mol.
An aqueous solution dissolved to 1% by weight was further added thereto and stirred for 2 hours. The liquid separated into two layers at the beginning of stirring, but became a transparent and homogeneous solution after stirring for 2 hours. When this solution was heated in an oven at 80 ° C. for 12 hours, ethanol, an aqueous solution of formic acid, water generated by the polycondensation reaction, and the like were volatilized. As a result, the solution, which initially had a weight of about 91.2 g and a volume of about 100 cm ³ , had its weight and volume reduced to about 30% to a weight of about 27 g and a volume of about 30 cm ³ . The solution thus obtained is referred to as solution A. Solution A contained little ethanol and water, and about 50% of the ethoxy groups originally contained in phenyltriethoxysilane and dimethyldiethoxysilane remained as OH groups. This solution A
0.001 mol of methyl hydrogendiethoxysilane was added to the mixture and stirred. This is referred to as solution B.

[Application and Heat Treatment of Solution to Mold or Substrate] The solution A or B is poured on the surface of the mold 2 as schematically shown in FIGS. 1 and 2 by the mold pouring method. In the substrate pouring method, the layers 1 and 5 having a thickness of 50 μm or more and 1 mm or less are formed by schematically pouring the mixture onto the surface of the substrate 7 as shown in FIG. 5, and heated to a temperature of 140 to 180 ° C. for 20 to 120 minutes. ,
Heated. The temperature of the heat treatment differs depending on the type of the solution. In the case of the solution A, the heat treatment was started from 140 to 160 ° C., gradually raised to 180 ° C. over 20 minutes, and held for 40 minutes.
The solution B was heat-treated at 160 ° C. for 20 minutes. By these heat treatments, a plastically deformable gel film (viscosity: 10 ⁴ to 10 ⁸ poise) was formed on the mold 2 or the substrate 7.

[Joining / Heat Treatment / Release] In the case of the mold pouring method, as shown in FIG. 3, the surface of the base material 3 is brought into contact with the coating surface (gel film). 250
C. for 20 to 60 minutes to bond to the substrate. After the coating film was completely gelled, the mold 2 was separated from the substrate 3 and released. As a result, a fine uneven plate 4 to which a film on which the shape of the mold was transferred as shown in FIG. 4 was adhered.

In the case of the base material pouring method, as shown in FIG. 6, a mold 6 is pressed against the gel film 5 and heat-treated at 250 ° C. for 20 minutes while being pressed at a pressure of ² kg / cm ^2. Was carried out. Thereafter, the mold was released. As a result, a fine concavo-convex plate 8 to which the shape of the molding die was transferred as shown in FIG. 7 was obtained.

[Final Heating] The fine uneven plates 4, 8 obtained by releasing the mold were heated at 350 ° C. for 15 minutes to obtain an article having an uneven surface. The performance and characteristics of the obtained article having an uneven surface were evaluated by the following methods.

[Measurement of Variation in Convex Height] The variation in the convex height of the outermost layer was measured by measuring the height with a laser microscope.

[Measurement of Heat Resistance and Optical Properties] The articles having uneven surfaces manufactured in Examples and Comparative Examples are
After performing a heat resistance test at 2 ° C. for 2 hours, the temperature was returned to room temperature, and the occurrence of cracks (cracks) was observed to evaluate the heat resistance. Using a He-Ne laser, the diffraction pattern of the diffraction grating, the focusing performance of the microlens, and the amount of reflection inside the substrate at an incident angle of about 6 ° on the substrate surface were measured before and after the heat test. ,evaluated. The d-line refractive index of the film was measured using an Abbe refractometer.

Example 1 A glass substrate having a thickness of 1.1
A 10 cm square soda lime glass substrate (linear expansion coefficient: 1.0 × 10 ⁻⁵ / ° C.) was prepared. In addition, 80,000 parallel V-grooves (groove width 1 μm, groove depth 1 μm, groove cross section: equilateral triangle, groove length 9 cm, spacing between adjacent grooves (measured at the center of the groove) of about 80,000 parallel molds) A mold made of nickel (Ni) having a thickness of 2 μm (hereinafter referred to as “V-groove Ni mold”) was prepared. The substrate, the mold, and the solution A
According to the method, a fine uneven plate as a diffraction grating was formed in accordance with the substrate pouring method so that the film thickness of the flat region (the portion where the linear protrusion was not provided) was about 40 μm. The thickness of the solution is about 60 μm.
Start heating at 160 ° C and gradually increase to 180 ° C over 20 minutes
And kept for 40 minutes. The pressing pressure and heating conditions were a pressure of 2 kg / cm ² and 250 ° C. for 20 minutes, and the final heating conditions were 350 ° C. and 15 minutes.

The organopolysiloxane film produced as described above is transparent, has a flat portion with a thickness of about 40 μm,
The refractive index was 1.51. The film contained 18% by weight and 31% by weight of methyl and phenyl groups, respectively. The height of the linear protrusions of this substrate was measured at a total of 100 points at intervals of 9 mm in the length direction of ten linear protrusions randomly selected from 80,000, and the average height was 1.0 μm.
The standard deviation was 0.05 μm. As a result of evaluating the heat resistance of this substrate, no crack was generated in the film, and the appearance, the height of the convex portion of the film, its standard deviation, and the diffraction pattern changed compared to the values before the heat test. Was not seen.

[Comparative Example 1] Methyltriethoxysilane, ethanol and water were respectively used at a molar concentration ratio of 1: 1: 4.
, And 0.01 mol of hydrochloric acid as a catalyst was added thereto, followed by stirring at room temperature for about 30 minutes to prepare a sol-like solution.
A fine uneven substrate was formed by the method described in Example 1 using the same substrate and mold as in Example 1 except that the above sol solution was used instead of the solution A used in Example 1. But,
Cracks occur in the film during cooling after final heating at 350 ° C,
Part of the film was peeled off, and the dimensions could not be evaluated. As a result of evaluating the heat resistance of this substrate, cracks in the film were further increased and the film was further partially peeled. Therefore, the height of the convex portion of the film after the heat resistance test and the standard deviation thereof were not measurable, and the diffraction pattern showed a large change compared to before the heat resistance test.

Comparative Example 2 Phenyltriethoxysilane was mixed with ethanol and water at a molar concentration ratio of 1: 1:
Then, 0.01 mol of hydrochloric acid was added as a catalyst, and the mixture was stirred at room temperature for about 30 minutes to prepare a sol-like solution.
Example 1 was repeated using the same substrate and mold as in Example 1 except that the sol-like solution was used instead of the solution A used in Example 1.
A fine uneven substrate was formed by the method described in (1). But 350
Cracks occurred in the film during cooling after the final heating at ℃, and like the methyltriethoxysilane of Comparative Example 1, a part of the film was peeled off and could not be evaluated. The diffraction pattern of this substrate showed a large change compared to before the heat test.

Example 2 The same glass substrate as in Example 1 was used as the glass substrate, and a fine uneven substrate was formed using the solution A according to a mold pouring method. A substantially hemispherical arc-shaped concave portion having a radius of curvature of 30 μm as a molding die is closely contacted in the vertical direction for approximately 1 mm.
50, 150 closely in the horizontal direction, total about 22,50
A Ni mold having zero pieces was used. After the final heating, the thickness of the flat region is about 15 μm, and the maximum thickness from the top of the hemisphere is 40 μm.
A micro-asperity substrate as a microlens was formed so as to obtain m. The thickness of the solution applied to the Ni mold is about 60 μm, and the heat treatment conditions after the application are as follows: starting from 160 ° C., increasing the temperature to 180 ° C. in 20 minutes;
Hold for minutes. The heating condition after the substrate bonding was 250 ° C. for 20 minutes, and the final heating condition was 350 ° C. for 15 minutes.

The organopolysiloxane film produced as described above is transparent and has a maximum thickness of about 40 μm and a thickness of 1.5 μm.
An organopolysiloxane film having a refractive index of 1 was adhered to the surface of the glass substrate. The focal length of the manufactured microlens was 95 to 98 μm. The film contained 18% by weight and 31% by weight of methyl and phenyl groups, respectively. The height of the convex portion of the substrate (measured from the flat surface of the film (the surface opposite to the convex portion)) was measured for 100 randomly selected hemispherical convex portions.
The average height was 40.0 μm and the standard deviation was 0.12 μm. As a result of evaluating the heat resistance of the substrate, no cracks or peeling occurred in the film, and the focal lengths of all the convex portions were all 95 to 9
The diameter of the condensed spot was within the range of 8 μm, the same as before the heat resistance test, and the diameter of the condensed spot was measured by making parallel light incident perpendicularly from the opposite side of the film. It was within 3 μm, which was not different from the value before the heat test.

Example 3 A quartz substrate was used as the glass substrate, the V-groove Ni mold used in Example 1 was used as the mold, and the thickness of the flat region was determined according to the substrate pouring method using the solution B. Was formed to be about 100 μm. The heat treatment after application of the solution was performed at 160 ° C. for 20 minutes. Pressing pressure and heating conditions are pressure 2 kg / cm ² , 2
50 ° C. for 20 minutes, final heating conditions are 350 ° C., 1
5 minutes.

The organopolysiloxane film produced as described above was transparent, had a maximum thickness of about 100 μm, and a refractive index of 1.50. The film contained 18% by weight and 31% by weight of methyl and phenyl groups, respectively. As a result of evaluating the heat resistance of this substrate, no crack was generated in the film, and no change was observed in the appearance and the diffraction pattern.

From the results of the examples and comparative examples, it can be seen that the organopolysiloxane layer according to the present invention has high heat resistance and does not cause discoloration or delamination.

Example 4 3 mm thick glass substrate
To prepare a 25 mm square soda lime glass substrate. The mold used was a glass mold in which 50 half-cylindrical concave portions having a radius of curvature of 20 μm were arranged side by side on a glass mold and subjected to release coating. On this substrate, formamide was added to solution A at 5% of the metal alkoxide in solution A.
A lenticular lens was formed according to the substrate pouring method so that the solution C that had been mixed and stirred for 30 minutes had a liquid thickness of about 50 μm. The heat treatment after the application was performed at 160 ° C. for 60 minutes. The pressing pressure is 2 kg / cm ² ,
After release, final heating was performed at 350 ° C. for 15 minutes. The organopolysiloxane film produced as described above was transparent. The height of the columnar projections of this substrate is randomly 20
This measurement showed that the average height from the substrate surface was 30 μm and the standard deviation was 0.10 μm. As a result of evaluating the heat resistance of this substrate, no crack was generated in the film, and no change was observed in the appearance, the height of the projections of the film, its standard deviation, and the pitch of the projections.

[0061]

According to the present invention, the volume shrinkage of the polysiloxane film at the time of curing is small, and a large amount of alkyl groups such as methyl groups and aryl groups such as phenyl groups remain in the film, thereby increasing the elasticity of the film. (Less brittle), the strength of the film is high, and the film is less likely to crack. Accordingly, a high heat-resistant optical element or other article having a thick organopolysiloxane film structure can be obtained at low cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a mold according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which a sol-gel material is applied on the mold of FIG.

FIG. 3 is a sectional view showing a state where a substrate is brought into contact with the sol-gel material of FIG. 2;

FIG. 4 is a cross-sectional view showing the fine uneven substrate after release from the state shown in FIG. 3;

FIG. 5 is a cross-sectional view showing a state in which a sol-gel material is applied on a substrate according to another embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a state where a mold is pressed on the sol-gel material of FIG. 5;

FIG. 7 is a cross-sectional view showing the fine uneven substrate after release from the state of FIG. 6;

[Explanation of symbols]

 1,5 Sol-gel material 2,6 Mold 3,7 Base material 4,8 Fine uneven substrate

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29K 83:00 B29L 9:00 11:00

Claims (9)

[Claims] 1. A gelled film having a surface in which the sol-gel material is closely adhered between a substrate and a mold and arranged in a film shape, and then heated to reverse the surface shape of the mold. In the method for producing an article having an uneven surface coated on the surface of a material, the sol-gel material may be obtained by: (A) the following formula (1): R ₂ SiX ₂ (1) where R is an alkyl group; Is an alkoxyl group or a halogen atom, and (B) the following formula (2): R′SiX ′ ₃ (2) wherein R ′ is a substituted or unsubstituted aryl group;
X 'is an alkoxyl group or a halogen atom, the method for producing an article having an uneven surface, characterized by containing a silane compound represented by the following formula: 2. The sol-gel material contains the component (A) and the component (B) in an amount of 0.2 to 4 mol of the component (B) per 1 mol of the component (A). A method for producing an article having an uneven surface. 3. The method for producing an article having an uneven surface according to claim 1, wherein the component (A) is dimethyldiethoxysilane, and the component (B) is phenyltriethoxysilane. 4. The sol-gel material comprises the component (A),
(B) The solution containing the component, alcohol, water and the catalyst is hydrolyzed with stirring and heated to evaporate the volatile components therein and reduce the weight of the solution to 25% of the weight before heating.
The method for producing an article having an uneven surface according to any one of claims 1 to 3, wherein the article is reduced to about 35%. 5. The sol-gel material comprises the component (A),
The solution containing the component (B), alcohol, water and a catalyst is hydrolyzed with stirring and heated so that water and alcohol in the solution become substantially zero. 4. A method for producing an article having an uneven surface according to claim 1. 6. The sol-gel material is prepared by adding the alkoxyl group of a tetraalkoxysilane, an alkyltrialkoxysilane, an alkyl hydrogen dialkoxysilane, or a tetraalkoxysilane to the solution after the hydrolysis or the solution having a reduced mass. A halogenated silane in which part or all of the halogenated silane is substituted with halogen, a halogenated silane in which part or all of the alkoxyl group of the alkyl trialkoxysilane is substituted with halogen, or an alkoxyl group of the alkyl hydrogen dialkoxysilane The unevenness according to claim 4, wherein a halogenated silane partially or wholly substituted by halogen is added in a molar ratio of 10% or less based on the total moles of the components (A) and (B). A method for producing an article having a surface. 7. The sol-gel material according to claim 1, wherein formamide is added to the solution having a reduced mass in a molar ratio of 10% or less based on the total moles of the components (A) and (B). Item 7. The method for producing an article having an uneven surface according to item 4 or 6. 8. An organopolysiloxane film having irregularities on the surface of an article substrate having a thickness of 1 μm to 1 mm, wherein the film contains 5 to 25% by weight and 5 to 40% by weight of an alkyl group and an aryl group, respectively. An article having an uneven surface, which is contained by weight. 9. (A) 1 mol of dialkyldialkoxysilane (B) 0.2 to 4 mol of trialkoxysilane containing an aryl group or substituted aryl group (C) Alcohol (expressed in molar ratio) (A) component +
(B) 0.3 to 3 times the mole of the component (D) Acid catalyst (expressed in a molar ratio) (A) 3 to 20 times the mole of the component (B) (E) Water (expressed in a molar ratio) (A A) A composition for forming a film for producing an article having an uneven surface, comprising 2) to 20 times the molar amount of the component + the component (B).