JP3203686B2 - Coating solution and method for forming concavo-convex pattern using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating method which is preferably used for producing a substrate having a fine uneven pattern by transferring the unevenness to a coating film on the substrate by using a pressing die having fine unevenness. The present invention relates to a solution, and further relates to a method for producing a substrate having a fine uneven pattern using the coating solution.

[0002]

2. Description of the Related Art Conventionally, as a coating solution used in a method of manufacturing a substrate having a fine pattern by transferring the unevenness to a coating film using a pressing die having fine unevenness, for example, silicon tetraethoxide, titanium tetra n- Butoxide, ethanol, water, hydrogen chloride and an average molecular weight of 6
Those containing polyethylene glycol of J. 00 A
m. Ceram. Soc. , Vol. 73 (8) 199
0.

[0003]

However, when the above-mentioned conventional coating solution is used, it takes a long time until the film is sufficiently cured after pressing the mold against the coating film to transfer the concavo-convex pattern. However, there is a problem that heat treatment at an extremely high temperature is required and productivity is low. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems, and works on a coating film on a substrate in a short time at a low temperature such as room temperature by faithfully forming the shape of a fine uneven pattern of a mold. It is an object of the present invention to provide a coating solution suitable for forming a film with good properties and a method for forming a concavo-convex pattern using the same.

[0004]

According to the present invention, there is provided a method of forming a coating on a coating film.
By pressing a mold having a surface uneven pattern, the uneven pattern of the mold is pressed.
The mold is transferred to the coating film, and then the mold is released to form an uneven pattern.
The substrate with the coating film to which the turn has been transferred is used.
Heats the substrate with the coating film and burns the organic components in the coating film
To form an uneven pattern on the substrate.
A coating solution applied onto the substrate in order, the coating solution is seen containing a metal organic compound and a thickening agent and an alcohol capable of <br/> polycondensation or hydrolysis, the following general formula as the thickener Wherein at least two kinds of polyether glycols represented by
More polyether glycol type repeating structural units of the general formula are the same, and, unlike an average molecular weight of the phase, of which
The weight ratio of the mixture with the smallest mixing ratio is 20% or more.
If the weight ratio of the mixture with the highest mixing ratio is 80% or less,
Oh it is a coating solution and wherein the Rukoto. General _{formula: HO- (C n H 2n O} ) m -H (n, m is a positive integer)

In the second aspect of the present invention, a coating film is formed on a substrate using a coating solution, and a mold having a concavo-convex pattern on the surface is pressed on the coating film to apply the concavo-convex pattern of the mold to the coating film. Transfer, then release the mold to form a substrate with a coating film on which the concavo-convex pattern has been transferred, and then heat the substrate with the coating film to burn the organic components in the coating film,
A method for forming a concavo-convex pattern on a substrate, wherein the coating solution contains a metal organic compound capable of polycondensation or hydrolysis, a thickener, and an alcohol, and the thickener is a poly (poly) represented by the following general formula: contains two or more kinds of ether glycols, the more general _{formula: HO- (C n H 2n O} ) m -H (n, m is a positive integer) the polyether glycol repeating structural units of the general formula but the same, and, unlike an average molecular weight of the phase, of which the mixing ratio
Weight ratio of more than 20%
Most often the weight ratio of the slip ratio is a method characterized in der Rukoto 80% or less.

[0006] The metal organic compound used in the coating solution of the present invention is not particularly limited as long as the compound increases the viscosity of the solution by a polycondensation or crosslinking reaction. For example, M (OR) n [M is a metal,
R is an alkyl group, n is an integer of 1-4], a metal alkoxide, a chelate complex and -Cl, -C00H, -C00 used in a method usually called a sol-gel method.
R, -NH _2, Formula 1, or polycondensation of 2 such as Structural Formula
Examples are metal organic compounds containing functional groups capable of performing a crosslinking reaction
Can be shown. Among them, metal alkoxides are preferred and used
You.

[0007]

Embedded image

[0008]

Embedded image

Examples of the metal of the metal organic compound include silicon, titanium and zirconium. Examples of the metal organic compound of silicon include silicon alkoxides such as silicon tetramethoxide, silicon tetraethoxide, silicon tetrapropoxide, and silicon tetrabutoxide. Examples of titanium metal organic compounds include titanium alkoxides such as titanium tetramethoxide, titanium tetraethoxide, titanium tetrapropoxide, and titanium tetrabutoxide, titanium acetylacetonate complexes such as diisopropoxybisacetylacetonatotitanium, and octylic acid. Organic acid titanium salts such as titanium are exemplified. Examples of the organic compound of zirconium include zirconium tetramethoxide, metal alkoxides such as zirconium tetraethoxide, zirconium tetrapropoxide, zirconium tetrabutoxide, zirconium acetylacetonate complex, and zirconium organic acid salt.

[0010] The metal organic compound contained in the coating solution of the present invention may be a single metal organic compound, or may contain two or more different metal organic compounds as a mixture or as a polymer. Good. After coating the coating solution of the present invention on a substrate and transferring a concavo-convex pattern to the surface of the coating film, the coating film with the transfer pattern is heated and baked to remove organic components in the coating film, and is mainly composed of an inorganic oxide. When a glass substrate for an optical disk having an uneven film is used, it is preferable that the refractive index of the uneven film is substantially the same as the refractive index of the glass plate. When a float glass plate having a refractive index of 1.52 is used as the glass substrate, the uneven film mainly composed of the above inorganic oxide is a film composed of a mixture of silicon dioxide and titanium dioxide, and a film composed of a mixture of silicon dioxide and zirconium dioxide. However, it is preferable because the refractive index of the glass plate can be made the same, and at the same time, the weather resistance is better than that of a film composed of a single component of silicon dioxide. Therefore, the metal organic compound contained in the coating film of the present invention is preferably a mixture or polymer of a silicon organic compound and a titanium organic compound, or a mixture or polymer of a silicon organic compound and a zirconium organic compound.

When the metal organic compound in the coating solution is composed of a silicon organic compound and a titanium organic compound, the ratio of silicon to titanium does not reduce the storage stability of the coating solution, and the titanium is not added in the above molar ratio of oxides. 5
It is preferably 0% or less, and more preferably 7 to 27% in order to make the refractive index almost the same as that of the glass plate.

When the metal organic compound in the coating solution is composed of a silicon organic compound and a zirconium organic compound, the ratio of silicon to zirconium does not lower the storage stability of the coating solution, and the ratio of zirconium to the above oxide molar ratio is not limited. Is preferably 50% or less, and more preferably 10 to 30% for making the refractive index almost the same as that of the glass plate.

In the coating solution of the present invention, the viscosity of the solution is increased to facilitate the formation of a coating film on the substrate, and the coating film is kept in a soft state (moderately viscous state) until a mold is pressed against the substrate. ), And a thickener is contained in order to faithfully transfer the concave and convex pattern of the mold to the coating film. Examples of the thickener include polyether glycols having the same repeating structural unit and different average molecular weights.
More than one species is used in combination. The polyether glycol is represented by the following general formula, wherein n is a polyethylene glycol of 2, n is a polypropylene glycol of 3, and n
A chain polyether such as polytetramethylene ether glycol having a molecular weight of 4 is preferably used. And polyethylene glycol is most preferably used. General _{formula: HO- (C n H 2n O} ) m -H (n, m is a positive integer)

When two kinds of polyether glycols having different average molecular weights are mixed and contained in the coating solution, the average molecular weight of the polyether glycol having a smaller average molecular weight is set to 200 or less, and the polyether glycol having a larger average molecular weight is It is preferable that the average molecular weight of the glycol be 600 or more.

The total weight of the thickener is preferably in the range of 0.1 to 10 times the weight (converted oxide weight) assuming that the metal organic compound has been completely converted to metal oxide. When the total weight of the thickener is less than 0.1 times the reduced oxide, the applied film is already hardened and undergoes plastic deformation when the mold is pressed against the applied film because the applied film is rapidly cured. And it becomes difficult to transfer the fine concave-convex pattern of the mold to the coating film. On the other hand, if it exceeds 10 times the equivalent oxide, curing of the coating film proceeds very slowly, so that the mold and the coating film can be pressed together, but after the release, the pattern transferred to the coating film is cured to the extent that it does not deform. However, a long pressing time and a relatively high heat treatment temperature are required, and productivity is deteriorated. Further, when the total amount of the thickener further increases, when the coating film after the transfer of the concavo-convex pattern is fired at a high temperature to form a vitreous film, the contraction amount of the pattern increases,
This is not preferable because the dimensional accuracy of the transfer decreases.

The alcohol used in the present invention is not particularly limited, but lower alcohols such as ethanol, propanol and butanol are preferably used.

The coating solution of the present invention is preferably added with water or an acid as a catalyst for promoting a hydrolysis reaction or a polycondensation reaction, if necessary. Examples of the acid include hydrochloric acid, nitric acid, acetic acid, sulfuric acid, and hydrofluoric acid. Organic solvents such as alcohols,
It is mixed with the above-mentioned thickener and, if necessary, an acid or alkali hydrolysis catalyst to form a coating solution.

[0018]

The polyether glycol having a higher average molecular weight among the polyether glycol thickeners contained in the coating solution of the present invention lowers the initial hardness of the coating film applied on the substrate. This makes it possible to press the mold against the soft coating film after the formation of the coating film, so that it is possible to faithfully transfer the concave and convex pattern of the mold to the coating film surface. Further, the polyether glycol having a low average molecular weight, the type is to increase the cure rate at a temperature close to room temperature the gel coating film caused by being pressed. Thus, mold intends line short press after releasing near room temperature
Never cause collapse of the type also transferred to the coating film alone. Therefore, it is possible to transfer a fine concavo-convex pattern in a short time at a low temperature such as room temperature.

[0019]

EXAMPLE An example in which a fine concavo-convex pattern was formed on a glass substrate using the coating solution of the present invention will be described below.
Table 1 shows the compositions of the coating solutions used in the examples.
FIG. 1 is a view for explaining a step of forming a concavo-convex pattern on a substrate using the coating solution of the present invention.
1A, a coating film 2 is applied on a base 1. FIG.
(B) shows a state in which the mold 3 having the uneven pattern 4 on the surface of the coating film 2 is pressed to transfer the uneven pattern of the mold to the coating film 2. Thereafter, when the mold is released (FIG. 1 (c)), the substrate 6 having the cured concavo-convex pattern 5A formed on the substrate 1 is obtained. Further, the base 6 is heated and fired to form the base 6 on which the uneven pattern 5B made of an oxide is formed.

[0020]

[Table 1]

Example 1 As a starting material, silicon tetraethoxide (Si (OC
Using ₂ H _{5) 4)} and titanium tetra-n-butoxide _{(Ti (OC 4 H 9)} 4). The metal organic compound was heated and fired, and the raw material ratio was determined so that the molar ratio of SiO ₂ and TiO ₂ was finally 83.5: 16.5. Ethanol was used as a solvent, and hydrogen chloride was used as a hydrolysis catalyst. The amount of water to be added and the amount of ethanol were 4 times and 5 times the molar ratio of silicon tetraethoxide, respectively.

Dilute hydrochloric acid (3% by weight) was added to an ethanol solution of silicon tetraethoxide, and the mixture was stirred at room temperature for 15 minutes. Further, an ethanol solution of titanium tetranormal butoxide was added, followed by stirring for 15 minutes to effect hydrolysis. . The solution thus obtained was colorless and transparent, and the solution was further diluted with ethanol to control the thickness of the coating film. To the solution thus obtained, polyethylene glycol (PEG6) having an average molecular weight of 600 was added
(PEG6) / (TiO ₂ + SiO ₂ ) = 0.0 in terms of weight ratio to the total amount of TiO ₂ and SiO ₂ which are final oxides.
Further, polyethylene glycol (PEG2) having an average molecular weight of 200 was added to the total amount of TiO ₂ and SiO ₂ , which is the final oxide, in a weight ratio of (PEG) to be 375.
2) / (TiO ₂ + SiO ₂ ) = 0.375 and uniformly dissolved, and the coating solution (No. 1 in Table 1)
Solution).

Using this coating solution, a coating film having a thickness of 0.3 μm was formed on a disk substrate made of chemically reinforced soda-lime glass having an outer diameter of 130 mm and a thickness of 1.2 mm by spin coating. Next, the glass substrate with the coating film was placed in a vacuum press apparatus, and the pressure was reduced to about 1 × 10 ⁻⁵ Torr. Then, a peak height of 0.09 was applied to the glass substrate with the coating film.
A mold having an outer diameter of 130 mm and a thickness of 1.2 mm having a spiral peak having a peak width of 0.7 μm and a peak interval of 1.6 μm in a range of a radius of 25 mm to 60 mm is joined, and then a pressing pressure of 50 kgf / cm ^2. Was pressed.

Thereafter, heating is carried out in this state,
For various times to cure the coating film. The heat treatment times studied are 5 minutes, 10 minutes and 15 minutes. After the heat treatment for a predetermined time, the mold and the glass disk are released,
In addition, each glass disk is
A final bake of 5 minutes was performed. In any of the curing heat treatments performed by this baking operation, the coating film has a non-uniform pattern having a fine irregularity pattern having a thickness of about 0.2 μm, which is similar to a glass body, because ethanol and moisture are scattered and the added PEG is decomposed by combustion. It was a crystalline film.

When the surface of the grooved glass disk produced by the above operation was observed by SEM,
The transfer of the concavo-convex pattern by either heat treatment for 15 minutes or 15 minutes also results in a groove depth of about 0.75 μm and a groove width of about 0.1 μm.
It was found that a good groove shape of 7 μm and a groove interval of about 1.6 μm was formed on the entire surface.

The weight ratio between polyethylene glycol and oxide is calculated as (PEG6 + PEG2) / (TiO ₂ / SiO ₂ ) =
By keeping the weight ratio of PEG6 and PEG2 constant within a range of 0.25 <(PEG6 / PEG2) <4.0, the coating solution No. 2, No. Similar results were obtained for the coating solution using No. 3.

Example 2 A solution was prepared in the same manner as in Example 1, except that polyethylene glycol (PEG20) having an average molecular weight of 2000 was used.
Is expressed by a weight ratio of (PEG20) / (TiO ₂ + SiO ₂ ) to the total amount of TiO ₂ and SiO ₂ which are final oxides.
= 0.375, and PEG2 was added in a weight ratio of (PEG) to the total amount of TiO ₂ and SiO ₂ as final oxides.
2) / (TiO ₂ + SiO ₂ ) = 0.375, and uniformly dissolved to obtain a coating solution (No. 4 in Table 1).
Solution).

In the same manner as in Example 1, a coating film was formed using the above coating solution. Next, the glass substrate with the coating film is placed in a vacuum press apparatus, and the pressure is reduced to about 1 × 10 ⁻⁵ Torr, and a spiral peak having a peak height of 0.09 μm, a peak width of 0.7 μm, and a peak interval of 1.6 μm is provided. Outer diameter 130 with section
A mold having a thickness of 1.2 mm and a thickness of 1.2 mm was joined, and then pressed at a pressing pressure of 50 kgf / cm ² .

Thereafter, heating is carried out in this state,
For various times to cure the coating film. The heat treatment times studied are 5 minutes, 10 minutes and 15 minutes. After the heat treatment for a predetermined time, the mold and the glass disk are released, and each glass disk is subjected to 15 ° C. at 350 ° C.
A final bake of minutes was performed. As a result, the coating film was an amorphous film having a fine pattern having a thickness of about 0.2 μm similar to a glass body.

When the surface of the grooved glass disk produced by the above operation was observed by SEM, it was found that the pattern transferred at any heat treatment temperature had a groove depth of about 0.7.
It was found that a good groove shape of 6 μm, a groove width of about 0.7 μm, and a groove interval of about 1.6 μm was transferred to the entire surface.

Ratio of polyethylene glycol to oxide (PEG20 + PEG2) / (TiO ₂ + SiO ₂ ) =
With the constant of 0.75, the weight ratio of PEG20 and PEG2 was changed within the range of 0.25 <(PEG20 + PEG2) <4.0. 5, no. Similar results were obtained for the coating solution using No. 6.

Example 3 In the same manner as in Example 1, the composition 9TiO ₂ .91SiO
₂ (mol%) solution, and this time, PEG6 was added in a weight ratio of (PEG6) / (TiO ₂ + SiO ₂ ) = 0.3 with respect to the total amount of TiO ₂ and SiO ₂ as the final product oxide.
5. Further, PEG2 was replaced with TiO ₂ as the final oxide produced.
In a weight ratio to the total amount of ten SiO ₂ (PEG2) /
It was added to a (TiO ₂ tens SiO ₂₎ = 0.35, a material obtained by uniformly dissolving the coating solution (a solution of No.7 in Table 1).

In the same manner as in Example 1, a coating film was formed using this coating solution. Next, the glass substrate with the coating film is placed in a vacuum press apparatus, and the pressure is reduced to about 1 × 10 ⁻⁵ Torr, and a spiral peak having a peak height of 0.09 μm, a peak width of 0.7 μm, and a peak interval of 1.6 μm is formed. Outer diameter 130 with section
A mold having a thickness of 1.2 mm and a thickness of 1.2 mm was joined, and then pressed at a pressing pressure of 50 kgf / cm ² .

Thereafter, heating is carried out in this state,
For various times to cure the coating film. The heat treatment times studied are 5 minutes, 10 minutes and 15 minutes. After the heat treatment for a predetermined time, the mold and the glass disk are released,
In addition, each glass disk is
A final bake of 5 minutes was performed. The coating film was an amorphous film having a fine pattern having a thickness of about 0.2 μm similar to a glass body.

When the surface of the grooved glass disk produced by the above operation was observed by SEM, it was found that the pattern transfer at any heat treatment temperature had a groove depth of about 0.7.
It was found that a good groove shape of 6 μm, a groove width of about 0.7 μm, and a groove interval of about 1.6 μm was transferred to the entire surface.

The ratio of polyethylene glycol to the total amount of oxides is expressed as (PEG6 + PEG2) / (TiO ₂ + Si
O ₂ ) = 0.70 and the weight ratio of PEG6 to PEG2 was changed within the range of 0.25 <(PEG6 / PEG2) <4.0. 8, no. 9
The same results were obtained for the coating solution using.

Comparative Example 1 In the same manner as in Example 1, the weight ratio of PEG6 to the total amount of the final oxides TiO ₂ and SiO ₂ was (PEG6) / (TiO ₂ + SiO ₂ ) = 0.75. A coating solution was prepared by dissolving such that

Using the above coating solution, a pattern transfer experiment was performed in the same manner as in Example 1. The heat treatment conditions during die pressing during the transfer of the fine pattern are 60 ° C.-5 minutes, 60 ° C.-10 minutes, and 60 ° C.
15 minutes, 80 ° C. for 5 minutes, and 100 ° C. for 5 minutes.

When the surface of the manufactured grooved glass disk was observed with an SEM, it was found that only a film subjected to heat treatment at 100 ° C. for 5 minutes had a good groove shape formed on the entire surface. In the case of molding under other conditions, the hardness of the coating film at the time of release was insufficient, and defects due to re-deformation of the coating film occurred.

Comparative Example 2 In the same manner as in Example 1, PEG2 was converted to (PEG2) / (TiO ₂ + SiO ₂ ) = 0.75 by weight ratio with respect to the total amount of TiO ₂ and SiO ₂ , which are final oxides. A coating solution was prepared by dissolving such that

Using the above coating solution, a pattern transfer experiment similar to that in Example 1 was performed. The heat treatment conditions during die pressing during the transfer of the fine pattern are 60 ° C.-5 minutes, 60 ° C.-10 minutes, and 60 ° C.
15 minutes, 80 ° C. for 5 minutes, and 100 ° C. for 5 minutes.

Observation of the surface of each of the grooved glass discs by SEM revealed that no fine pattern was formed on any of the glass discs. In either case, the hardness of the film was already too high when the mold was pressed against the coating film, and the coating film was not plastically deformed even when the die was pressed.

Comparative Example 3 A molding experiment was performed in Comparative Example 2 in which the added amount of PEG2 was further increased. PEG2 is obtained by weight ratio (PEG) to the total amount of TiO ₂ and SiO ₂ which are final oxides.
2) A coating solution was prepared which was dissolved so that / (TiO ₂ + SiO ₂ ) = 1.0.

A pattern transfer experiment similar to that of Example 1 was performed using the above coating solution. The heat treatment conditions during die pressing during the transfer of the fine pattern are 60 ° C. for 5 minutes, 80 ° C. for 5 minutes,
0 ° C.-5 minutes.

When the surface of each of the grooved glass disks was observed by SEM, no good fine pattern was formed on any of the transfer glass disks. In either case, the hardness of the film was already too high when the mold was pressed against the coating film, and the coating film was not plastically deformed even when the die was pressed.

[0046]

The coating film obtained from the coating solution of the present invention has a low initial hardness, and the film hardness sharply increases by heat treatment. Therefore, by transferring a fine uneven pattern using the coating solution of the present invention, it is possible to form a desired fine uneven pattern on a substrate in a short time at a low temperature without impairing workability and pattern quality. .

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a method for forming a concavo-convex pattern on a substrate using a coating solution of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base, 2 ... Coating film, 3 ... Type, 4 ...
Uneven pattern on the mold surface, 5A ... cured uneven pattern. 5B: an uneven pattern made of an oxide, 6 ...
・ Substrate with uneven pattern

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-235465 (JP, A) JP-A-4-68023 (JP, A) JP-A-59-134705 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) C09D 1/00-201/10

Claims (3)

(57) [Claims] 1. A mold having an uneven surface pattern on a coating film.
Press to transfer the concave and convex pattern of the mold to the coating film,
After the mold is released, with a coating film on which the uneven pattern is transferred
And then heating the substrate with the coating film to form the substrate.
By burning the organic components in the cloth film, the concave
Coating solution applied on a substrate to form a convex pattern
Wherein the coating solution comprises a metal organic compound capable of polycondensation or hydrolysis, a thickener and an alcohol,
The compound is a silicon organic compound, a titanium organic compound,
Comprise any of a zirconium organic compound, and said thickener is a polyether glycol the general formula represented by the following general _{formula: HO- (C n H 2n O} ) m -H (n, m is a positive integer) contains 2 or more, two or more polyether glycol the repeating structural units of the above general formula are the same, and, unlike an average molecular weight of the phase, most small inner mixing ratio
The weight ratio of the food is more than 20%,
Coating solution weight ratios of those often characterized der Rukoto 80% or less. 2. The organic compound according to claim 1, wherein said metal organic compound includes at least one of a titanium organic compound, a zirconium organic compound, and a silicon organic compound.
2. The coating solution according to 1 . 3. A coating film is formed on a substrate using a coating solution, and a mold having an uneven pattern on the surface is pressed on the coating film to transfer the uneven pattern of the mold to the coating film. The mold is released to form a substrate with a coating film on which the concave / convex pattern is transferred, and thereafter, the substrate with the coated film is heated to burn the organic components in the coated film, thereby forming a concave / convex pattern on the substrate. The coating solution comprises a metal organic compound capable of polycondensation or hydrolysis, a thickener and an alcohol, wherein the organic metal compound is a silicon organic compound,
Tantalum organic compound or zirconium organic compound
Include or and the thickener is a polyether glycol the general formula represented by the following general _{formula: HO- (C n H 2n O} ) m -H (n, m is a positive integer) from two or more becomes, and, two or more polyether glycols said the repeating structural unit of the above general formula are the same, and, unlike an average molecular weight of the phase, the out mixing ratio more
Although the weight ratio is less than 20%, the mixing ratio
Wherein the der Rukoto than 80 percent by weight of those many Innovation.