JP2019023269A - Method for producing silicon oxide thin film-forming binder liquid and coating liquid - Google Patents

Abstract

To provide a method for producing silicon oxide thin film-forming binder liquid that is suitable for forming a silicon oxide thin film having excellent base material adhesion and high porosity.SOLUTION: The present invention provides a method that includes subjecting a hydrolyzable silane compound to hydrolysis and condensation reactions, to produce silicon oxide thin film-forming binder liquid comprising a composition resulting from the reactions. The used hydrolyzable silane compound comprises a bifunctional, hydrolyzable silane compound, at least 50 wt.% of which is a multimer. In absence of silica particles, an acid catalyst aqueous solution is continuously dropped in a hydrophilic solvent solution with the hydrolyzable silane compound dissolved therein, under agitation conditions, to perform the reactions.SELECTED DRAWING: None

Description

  TECHNICAL FIELD The present invention relates to a binder liquid for forming a silicon oxide thin film and a method for producing a coating liquid, and particularly relates to a binder liquid for forming a silicon oxide thin film using a hydrolyzable silane compound and a method for producing the coating liquid.

  A silicon oxide thin film is expected as a primer layer in various fields by utilizing its hydrophilicity, but excellent adhesion to a substrate is required as a basic characteristic when used as a primer layer. As one method for forming a silicon oxide thin film on various substrates, a method using a hydrolyzable silane compound is known as shown below.

  For example, in the field of a method for producing a low reflection processed article, a binder liquid containing (1) silica fine particles, (2) a hydrolyzable silane compound, water, a hydrolysis catalyst for the silicon compound, and a solvent on a resin substrate. The mixture is reacted to hydrolyze the silicon compound, and then (3) a low-reflective layer solution obtained by adding a curing catalyst that promotes the condensation of silanol groups is coated on a resin substrate, and reaction-cured at a predetermined temperature. And a method of forming a low reflection layer containing silica fine particles and a binder has been proposed (Patent Document 1).

  The above-mentioned proposed hydrolyzable silane compound also discloses an embodiment containing at least one organosilicon compound that has been oligomerized in advance. And in this case, it is described that by performing hydrolysis in the presence of fine particles, the fine particles and the binder, the entanglement between the binders, and further polymerization proceeds, and the polymerization at the time of curing can be performed more efficiently. ing.

Further, in the above proposal, the following teaching is also given regarding the hydrolysis catalyst.
That is, the acid catalyst is preferable because the condensation polymerization reaction rate is lower than the hydrolysis reaction rate, and a large amount of hydrolysis reaction product M (OH) _n is produced, which effectively acts as a binder. . On the other hand, in the case of a basic catalyst, the condensation polymerization reaction rate is higher than the hydrolysis reaction rate, so that the metal alkoxide becomes a fine-particle reaction product and increases the particle size of the silica fine particles that are originally present. As a result, the action of the metal alkoxide as a binder is reduced.

  In the field of forming an antireflection layer on the glass surface, (a) chain silica particles, (b) a hydrolytic condensate of a specific organoalkoxysilane, (c) a specific silane compound, (d) A composition containing a solvent has also been proposed (Patent Document 2). In this proposal, as a specific example of the hydrolyzed condensate of organoalkoxysilane, “methyl silicate oligomer, average polymerization degree 4”, water was added to the methyl silicate oligomer and heated at 70 ° C. for 1 hour. Hydrolysates are listed. The hydrolyzed condensate of organoalkoxysilane acts as a matrix that connects the particles during the formation of the coating layer, and (c) the specific silane compound acts to improve the adhesion of the antireflection layer to the substrate and increase the crosslink density. The explanation to do is made.

International Publication No. 2004/070436 Pamphlet Japanese Patent Laying-Open No. 2015-21029

  The binder acts between the silica particles to form a silicon oxide thin film, and has an action of adhering the silicon oxide thin film to the substrate surface. And as described in the above-mentioned prior literature, the binder can be obtained as a reaction composition obtained by hydrolyzing and condensing a hydrolyzable silane compound (such as organoalkoxysilane).

  According to the knowledge of the present inventors, the action of the binder varies greatly depending on the properties of the reaction composition obtained by the difference in the production method, and an ideal binder is a straight chain having a large amount of -OH groups. It is a reaction composition rich in structure.

  The present invention has been made from the above viewpoint, and an object of the present invention is to provide a method for producing a silicon oxide thin film-forming binder liquid suitable for forming a silicon oxide thin film having excellent substrate adhesion. Another object of the present invention is to provide a method for producing a coating liquid for forming a silicon oxide thin film using the binder liquid.

  The object of the present invention can be achieved by the following present invention which defines the hydrolyzable silane compound to be used and the conditions of the hydrolysis and condensation reaction.

(1) A method for producing a silicon oxide thin film-forming binder liquid comprising a hydrolyzable and condensed reaction of a hydrolyzable silane compound and comprising the reaction composition, comprising a bifunctional hydrolyzable silane compound and at least 50 Using a hydrolyzable silane compound whose weight% is a multimer, an acid catalyst aqueous solution is continuously dropped under stirring conditions into a hydrophilic solvent solution in which the hydrolyzable silane compound is dissolved in the absence of silica particles. A method for producing a binder liquid for forming a silicon oxide thin film, wherein the reaction is carried out and diluted with a hydrophilic solvent (first invention).

(2) A method for producing a coating liquid for forming a silicon oxide thin film, wherein the binder liquid obtained by the above production method and silica fine particles are mixed (second invention).

  According to the manufacturing method of the binder liquid for forming a silicon oxide thin film and the coating liquid of the present invention, it does not require an additive component for improving the adhesion and increasing the crosslink density to the base material proposed in the above-mentioned prior literature, A silicon oxide thin film excellent in substrate adhesion can be formed, and the obtained silicon oxide thin film is suitable as a primer layer in various fields.

  Hereinafter, the present invention will be described in detail.

  First, the hydrolyzable silane compound will be described.

  The hydrolyzable silane compound is a silane compound having a hydrolyzable group such as an alkoxy group, an alkoxyalkoxy group, an acyloxy group, an aryloxy group, an aminoxy group, an amide group, a ketoxime group, an isocyanate group, and a halogen atom.

  In the present invention, an alkoxysilane compound is preferably used. Examples of the alkyl group of the alkoxy group (—OR) include lower alkyl groups such as a methyl group, an ethyl group, a propyl group, and a butyl group. One having 1 to 4 functional groups is known depending on the number of hydrolyzable groups.

  Representative examples of alkoxysilane compounds include dimethyldimethoxysilane (DMDMS), methyltrimethoxysilane (MTMS), tetramethoxysilane (TMOS), dimethyldiethoxysilane (DMDES), methyltriethoxysilane (MTES), and tetraethoxysilane. (TEOS).

  The multimer of the hydrolyzable silane compound is obtained by condensation polymerization (oligomerization) of the above monomers by condensation. In this reaction, first, a silanol group (—Si—OH) is formed by hydrolysis of an alkoxy group. At the same time, alcohol (R—OH) is produced. Next, a siloxane bond (—Si—O—Si—O—) is formed by (dehydration) condensation of silanol groups, and this condensation is repeated to form a siloxane oligomer. The alkoxysilane compound multimer is preferably a tetramethoxysilane multimer in which R is a methyl group or a tetraethoxysilane multimer in which R is an ethyl group in terms of alkoxy group hydrolyzability and condensability. .

Multimeric structures include linear, branched, cyclic, and network structures. If a tetraalkoxysilane multimer is shown as having a linear structure, it is represented by the following general formula: .
[Chemical 1]
RO (Si (OR) ₂ O) _n R (I)

  In the general formula, n represents the degree of multimerization. Usually available multimers are compositions of multimers with different n and therefore have a molecular weight distribution. The degree of multimerization is expressed as an average n.

The degree of multimerization of a tetrafunctional hydrolyzable silane compound such as tetraalkoxysilane or a multimer thereof may be represented by “silica content”. The “silica content” is a mass ratio of silica (SiO ₂ ) produced from the compound, and can be obtained by measuring the amount of silica produced by stably hydrolyzing and firing the compound. The “silica content” also indicates the ratio of silica generated per molecule of the compound, and is a value calculated by the following formula.
[Equation 1]
Silica content (parts by mass) = degree of multimerization × molecular weight of SiO ₂ / molecular weight of the compound

  In the present invention, multimers having a degree of multimerization n of usually 2 to 100, preferably 2 to 70, and more preferably 2 to 50 are used. Since such multimers are already commercially available, it is easy to use them. As the degree of multimerization n increases, the molecular weight of the binder produced increases and the molecular weight distribution becomes wider, so that a multimer having a degree of multimerization n exceeding 100 is unsuitable for the present invention.

  Commercially available multimers of hydrolyzable silane compounds include MKC silicate MS51, MKC silicate MS56, MKC silicate MS57, MKC silicate MS56S (all of which are tetramethoxysilane multimers) manufactured by Mitsubishi Chemical Corporation, and methyl manufactured by Colcoat. Examples thereof include silicate 51 (tetramethoxysilane multimer), methyl silicate 53A, ethyl silicate 40, ethyl silicate 48, ethyl silicate 40 and silicate 45 (all of which are tetraethoxysilane multimers) manufactured by Tama Chemical Industry.

  In the present invention, a hydrolyzable silane compound composed of a bifunctional hydrolyzable silane compound and having at least 50% by weight as a multimer is used. The multimer ratio in the hydrolyzable silane compound is preferably 70% by weight or more.

If the amount of the hydrolyzable silane compound used is small, it is difficult to achieve the object of the present invention. The reason is estimated as follows.
That is, OH groups are reduced by the hydrolysis and condensation reactions described below, which are received by the monomer, and branched, cyclic, and network structures are increased in the reaction composition.

  Next, conditions for the hydrolysis and condensation reaction will be described.

  In the present invention, the above reaction is performed in the absence of silica particles. Since the binder liquid is made into a coating liquid for forming a silicon oxide thin film by adding silica particles, it is easy to manufacture the binder liquid in the presence of silica particles from the beginning.

However, when the above reaction is performed in the presence of silica particles, it is difficult to achieve the object of the present invention. The reason is estimated as follows.
That is, since the hydrolysis and condensation reaction are sequentially performed, if silica particles are present in the reaction process (by heating), each component generated during the reaction is adsorbed on the surface of the silica particles. This adsorption is a strong state in which the binder component OH group and the silica particle OH group are formed with hydrogen bonds or siloxane bonds, and there are OH groups that contribute to the adhesion of the binder to the substrate and the strength of the silicon oxide thin film. Will be reduced. Moreover, the binder component adsorbed on the silica particles serves as a crosslinking point, and increases the branched structure and the network structure. On the other hand, a reaction product produced in the absence of silica particles is rich in a linear structure having a large amount of OH groups. Therefore, in the present invention, a binder liquid is produced in the absence of silica particles, and the obtained binder liquid and silica fine particles are mixed at room temperature to produce a coating liquid for forming a silicon oxide thin film.

  The reaction is carried out by continuously dropping an acid catalyst aqueous solution under a stirring condition into a hydrophilic solvent solution in which a hydrolyzable silane compound is dissolved.

  The hydrophilic solvent is not particularly limited as long as it can dissolve the multimer of the hydrolyzable silane compound, but in general, alcohols such as methanol, ethanol, propanol, butanol, ethyl cellosolve, butyl cellosolve, propyl cellosolve And other glycols such as ethylene glycol, propylene glycol, and hexylene glycol are used.

  The amount of the hydrophilic solvent used is not particularly limited, but considering the applicability of the coating liquid for forming a silicon oxide thin film produced by mixing silica fine particles in a binder liquid, the ratio relative to 100 parts by weight of the hydrolyzable silane compound As usual, it is 0.1-100 weight times, Preferably it is 1-10 weight times. Incidentally, the hydrolyzable silane compound multimer is a composition comprising components having different degrees of multimerization as described above, and the viscosity increases as the degree of polymerization increases. On the other hand, a commercial product of the monomer, for example, dimethyldimethoxysilane, is usually a 99% by weight pure solution.

  Examples of the acid catalyst aqueous solution include aqueous solutions of hydrochloric acid and acetic acid. The hydrolysis and condensation reaction of the hydrolyzable silane compound does not use an acid catalyst, and it is not impossible to carry out with water alone. It is difficult to achieve this goal. The reason is estimated as follows.

  In other words, when no catalyst is used, the reaction is near neutral and the hydrolysis reaction is very slow, but the condensation reaction is a condition that proceeds rapidly, so in parallel from the state where the hydrolysis reaction does not proceed sufficiently. This is because a condensation reaction occurs and the molecular weight distribution of the product becomes wide. Moreover, since hydrolysis is inadequate and many unreacted alkoxy groups remain in a product, the storage stability of a binder liquid is bad and it may result in gelatinization.

The acid concentration in the acid catalyst aqueous solution is usually in the range of 0.1 to 0.0001% by weight, preferably 0.01 to 0.001% by weight. If the acid catalyst is used as such a low concentration aqueous solution, a large amount of water is entrained in the reaction system, and as a result, the reaction rate of the condensation reaction, which is a competitive reaction, can be suppressed. Therefore, as a tendency, OH groups generated by hydrolysis disappear at an appropriate rate, and it becomes easy to obtain a reaction composition rich in a linear structure having a large amount of OH groups.

  By the way, when the acid concentration is too small, the object of the present invention tends to be difficult to achieve due to the same purpose as in the case where the reaction was performed without using the acid catalyst. If it is large, hydrolysis proceeds rapidly but the condensation reaction is slow, so that only a reaction composition having a low molecular weight can be obtained, and the effects of adhesion to the substrate and scratch resistance are dramatically reduced.

  The amount of the acid catalyst used is usually 0.001 to 10 mmol, preferably 0 with respect to 100 mol of the total amount of hydrolyzable groups (typically alkoxy groups) of the hydrolyzable silane compound in the hydrophilic solvent solution. 0.01 to 10 mmol.

  The acid catalyst aqueous solution is continuously dropped, and the dropping rate is appropriately selected so that the temperature in the reaction system does not rise rapidly. The dropping rate of the acid catalyst aqueous solution is usually 1 to 10 ml / min, preferably 3 to 5 ml / min, per 100 ml of the hydrophilic solvent solution. The dropped catalyst aqueous solution is immediately and uniformly diffused by stirring to be uniformly hydrolyzed. In addition, the stirring method can employ | adopt the method employ | adopted by the normal chemical reaction.

  The hydrolysis and condensation reaction of the hydrolyzable silane compound is actually performed sequentially and in parallel. In a preferred embodiment of the present invention, from the viewpoint of obtaining a reaction composition rich in a linear structure having a large amount of OH groups, the following hydrolysis and condensation reactions are carried out separately as much as possible. Divide into three stages.

(1) Hydrolysis reaction step:
It is carried out by dropping the acid catalyst aqueous solution into the hydrophilic solvent solution under stirring conditions. The reaction temperature is usually 5 to 50 ° C., preferably 10 to 40 ° C. When the reaction temperature is less than the above range, the hydrolysis reaction is too slow, and when the reaction temperature is over the above range, it is difficult to avoid the condensation reaction. The reaction temperature is controlled by the temperature / circulation amount of the refrigerant conducted to the reactor jacket, the dropping rate of the acid catalyst aqueous solution, and the like. When the boiling point of the hydrophilic solvent is low, the hydrolysis reaction is performed under reflux conditions. The reaction time is usually 1 to 60 minutes, preferably 5 to 30 minutes.

  The hydrolysis reaction is an exothermic reaction, and the temperature of the reaction solution usually rises by 1 to 15 ° C. In order to confirm that the hydrolysis reaction is substantially completed, it is preferable to continue stirring until the reaction temperature drops by 5 to 10 ° C. after completion of the dropwise addition of the aqueous acid catalyst solution.

(2) Condensation reaction step:
Following the above step, the reaction temperature is increased as necessary, and the reaction is carried out under stirring conditions. The reaction temperature is usually 40 to 80 ° C, preferably 50 to 60 ° C. If the reaction temperature is less than the above range, the condensation reaction becomes too slow, and if it exceeds the above range, it is difficult to avoid an excessive condensation reaction. The rate of temperature rise is usually 0.1 to 10 ° C./min. The reaction time is usually 1 to 120 minutes, preferably 5 to 60 minutes.

(3) Condensation reaction termination step:
The reaction solution is cooled to stop the condensation reaction. The cooling temperature is usually 10 to 30 ° C. At this time, it is more effective to stop the condensation reaction by cooling dilution by adding a hydrophilic solvent in order to reduce the concentration of the condensation reaction composition. The hydrophilic solvent is preferably the same as the reaction solvent, but another hydrophilic solvent may be used for adjusting the liquidity.

  The addition amount of the hydrophilic solvent is usually in the range of 50 to 150% by weight when expressed as the concentration of the hydrophilic solvent relative to the total amount of the hydrolyzable silane compound, the hydrophilic solvent subjected to the reaction, and the aqueous acid catalyst solution.

  According to the condensation reaction stopping step by the cooling dilution described above, the storage stability of the obtained binder liquid is increased, and the binder liquid can be manufactured so that the concentration can be adjusted to meet the requirements of each application.

  The weight average molecular weight of the resulting reaction composition is determined by the above condensation reaction step. A weight average molecular weight is 1000-5000 normally, Preferably it is 2000-4000. Such molecular weight corresponds to a multimer having a uniform multimerization degree n of 2 to 100.

  The weight average molecular weight is a value measured by gel permeation chromatography (GPC) under the following conditions.

[Solvent] Tetrahydrofuran [Device name] TOSOH HLC-8220GPC
[Column] Used by connecting TOSOH TSKgel Super HM-N (2) and HZ1000 (1).
[Column temperature] 40 ° C
[Sample concentration] 0.01% by mass
[Flow rate] 0.6ml / min
[Calibration Curve] PEG (Uses a calibration curve based on a 4-point cubic approximation of molecular weight 20000, 4000, 1000, 200).

  The binder liquid for forming a silicon oxide thin film comprising the above reaction composition is substantially transparent, and the turbidity measured by using a kaolin turbidimeter is 10 or less.

  Next, the manufacturing method of the coating liquid for silicon oxide thin film formation is demonstrated. In this invention, the coating liquid for silicon oxide thin film formation is manufactured by mixing the binder liquid obtained by the said manufacturing method, and silica fine particles.

  The silica fine particles are not particularly limited, and spherical non-aggregated silica fine particles having an average particle size of 5 to 100 nm, hollow non-aggregated silica fine particles having an average particle size of 10 to 100 nm, and chain aggregation having an average primary particle size of 5 to 100 nm. Examples thereof include silica fine particles composed of at least one kind of silica fine particles. These are appropriately selected according to the purpose of the silicon oxide thin film to be formed.

  Specific examples of the spherical non-aggregated silica fine particles include “Snowtex (registered trademark) -O”, “Snowtex (registered trademark) -O-40”, and “Snowtex (registered trademark) — OL "," Quatron (registered trademark) -PL-1 "," Quortron (registered trademark) -PL-3 "," Quortron (registered trademark) -PL-7 "manufactured by Fuso Chemical Industry, and the like.

  Specific examples of the chain aggregated silica fine particles include “Snowtex (registered trademark) -OUP” (average length: 40 to 100 nm), “Snowtex (registered trademark) -UP” (average) manufactured by Nissan Chemical Industries, Ltd. Length: 40 to 100 nm), “Snowtex (registered trademark) PS-M” (average length: 80 to 150 nm), “Snowtex (registered trademark) PS-MO” (average length: 80 to 150 nm), “Snowtex (registered trademark) PS-S” (average length: 80 to 120 nm), “Snowtex (registered trademark) PS-SO” (average length: 80 to 120 nm), “IPA-ST-UP” ( Average length: 40 to 100 nm), “Fine Cataloid F-120” manufactured by Nippon Shokubai Kasei Kogyo Co., Ltd., and the like.

  The coating liquid for forming a silicon oxide thin film is prepared at an appropriate concentration in consideration of coating properties when applied to a substrate, film thickness and smoothness of the coating film, and the like. Concentration adjustment is performed by adding the above-mentioned hydrophilic solvent. This concentration adjustment can be performed before or after mixing the silica fine particles.

  The substrate to which the coating liquid for forming a silicon oxide thin film is applied is arbitrary, but in general, a plastics substrate is used, which may be a film (100 μm or less) or a thicker sheet. . Incidentally, examples of plastics include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polyimide (PI), polymethyl methacrylate (PMMA), and cycloolefin polymer (COP). The surface of the substrate can be applied to either a surface-modified or untreated surface.

  The silicon oxide thin film is formed by drying and curing after application of the coating liquid.

  Application of the coating liquid is not particularly limited, and examples thereof include a dip coating method, a spin coating method, a die coating method, a spray coating method, a gravure coating method, a roll coating method, a curtain coating method, a screen printing method, and an inkjet printing method. it can.

  The coating thickness is appropriately selected according to the purpose of the silicon oxide thin film to be formed. Usually 50 to 5000 nm.

  Said drying is performed in order to remove a solvent, drying temperature is 50-80 degreeC normally, and a hot air dryer etc. are used suitably. The drying time is usually 1 to 10 minutes, preferably 1 to 5 minutes.

  The above curing treatment is mainly performed to bond silanol groups (Si-OH) contained in the binder liquid to oxygen-containing functional groups such as hydroxyl groups and carboxyl groups on the substrate surface, thereby forming a silicon oxide thin film. Is done.

  As the above curing treatment, a method of irradiating ultraviolet rays in the presence of oxygen is recommended. The ultraviolet rays include near ultraviolet rays (near UV, wavelength 200 to 380 nm), far ultraviolet rays (wavelength 10 to 200 nm), and extreme ultraviolet rays (extreme UV, wavelength 1 to 10 nm), but far ultraviolet rays are usually effective. Examples of the ultraviolet ray source include a low-pressure mercury lamp, a high-pressure mercury lamp, an excimer ultraviolet (excimer UV) lamp, a halide lamp, and a laser. The irradiation time of ultraviolet rays is usually 1 second to 3 minutes.

  In the case of a curing treatment using a plastics substrate as a substrate and irradiating with ultraviolet rays in the presence of oxygen, a silicon oxide thin film with significantly improved substrate adhesion is formed. The reason is estimated as follows.

  That is, the surface of the plastic substrate is activated (modified) by the active oxygen generated by the action of ultraviolet rays, and the silanol groups (Si—OH) contained in the binder liquid and the substrate surface are firmly bonded.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail from an Example, this invention is not limited to a following example, unless the summary is exceeded. The analysis methods in the following examples are as follows.

Example 1
<Manufacture of binder liquid for forming silicon oxide thin film>
(1) Hydrolysis reaction step:
In a 2 L jacketed reactor, 50 parts by mass of “KBM22” manufactured by Shin-Etsu Silicone (dimethylmethoxysilane content 99% by weight), “Silicate MS51” manufactured by Mitsubishi Chemical Co., Ltd. (average degree of multimerization n: 7, methyl silicate) (Oligomer content 99.8% by weight) 200 parts by mass and 500 parts by mass of ethanol were added, the reaction upper limit temperature was set to 40 ° C., and 330 parts by mass of 0.007% by weight hydrochloric acid aqueous solution was added dropwise over 10 minutes under stirring conditions. did. At this time, the reaction temperature increased by 5 to 10 ° C. due to the exothermic reaction. Stirring was continued until the reaction temperature dropped by 5-10 ° C. The ratio of the multimer in the bifunctional hydrolyzable silane compound (the ratio of silicate MS51 to the total amount of “KBM22” and “silicate MS51”) is 80% by weight.

(2) Condensation reaction step:
After dropping the aqueous hydrochloric acid solution, the temperature was raised to 60 ° C. over 30 minutes under stirring conditions, and the temperature was maintained at 60 ° C. for 30 minutes. Then, it cooled to room temperature.

(3) Condensation reaction termination step:
After cooling, 1100 parts by mass of ethanol was mixed and stirred for 30 minutes to obtain 2180 parts by mass of an alkoxysilane composition (A).

<Manufacture of coating liquid for forming silicon oxide thin film>
An alkoxysilane composition (B) 14180 was obtained by adding 12000 parts by mass of ethanol to 2180 parts by mass of the alkoxysilane composition (A) obtained above and stirring for 30 minutes.

  Silicon oxide thin film is obtained by adding 2040 parts by mass of spherical non-agglomerated silica (product “Snowtex O” manufactured by Nissan Chemical Industries, Ltd.) to 14180 parts by mass of the alkoxysilane composition (B) obtained above and stirring for 30 minutes. A forming coating solution was obtained.

(A) Evaluation of coating liquid for forming silicon oxide thin film:
Coating for forming a silicon oxide thin film obtained in Example 1 on a non-adhesive surface of a 125 μm thick polyethylene terephthalate (PET) film (“Cosmo Shine A-4100” manufactured by Toyobo Co., Ltd.) cut to 52 × 76 mm The liquid was dropped, and a thin film was prepared by coating at 1200 rpm for 30 seconds with a spin coater (“MS-A150” manufactured by Mikasa).

Then, in order to remove a solvent, it put into the constant temperature and constant temperature air blower (made by Yamato Kagaku company), and dried at 70 degreeC for 1 minute. Next, using a high-pressure mercury lamp (manufactured by Eye Graphics Co., Ltd.) in the atmosphere, irradiating ultraviolet rays with an illuminance of 130 mW / cm ² and an integrated light quantity of 1000 mJ / cm ² , a PET with a silicon oxide thin film having a thickness of 100 nm Obtained.

[Adhesion test method]
In accordance with JIS K5600, an adhesive test by cross-cut method was performed using an industrial 24 mm cello tape (registered trademark) manufactured by Nichiban Co., Ltd. as an adhesive tape, and the adhesion was evaluated.
That is, 25 grids with a 5 mm interval were made with a cutter knife, cellophane tape was applied to the surface of the membrane, and after peeling, the number of membranes remaining without peeling was counted and evaluated.
In addition, since the silicon oxide thin film has properties close to glassy, cracks are likely to occur when making a grid with a cutter knife, and its accurate adhesion test is difficult, so the grid spacing of JIS K5600 is Although it is 1 mm or 2 mm, the grid interval was changed to 5 mm.
The ratio (film residual ratio) of the number of squares that were not peeled off relative to the total squares (25) was obtained. The results are shown in Table 1.

[Moisture and heat resistance test]
The PET with silicon oxide thin film created in the examples and comparative examples is held for 30 minutes in an environmental tester (SH-641 manufactured by ESPEC) set in an environment with a temperature of 60 ° C. and a relative humidity of 95%. went. The lowered adhesion state was evaluated by the above-described adhesion test method. The results are shown in Table 1.

Comparative Example 1:
In Example 1, the silica used in the production process of the coating liquid for forming a silicon oxide thin film was changed to chain silica (product “Snowtex OUP” manufactured by Nissan Chemical Industries, Ltd.), and this was added and hydrolyzed. The process, the condensation reaction process, and the condensation reaction stop process are performed, and after cooling, 1100 parts by mass of ethanol is mixed and stirred for 30 minutes, and then 12,000 masses of ethanol used in the production process of the coating liquid for forming a silicon oxide thin film. A silicon oxide thin film-forming coating solution was produced in the same manner as in Example 1 except that the part was added. And it carried out similarly to Example 1, obtained PET with a silicon oxide thin film of thickness 100nm, and evaluated the adhesiveness of the silicon oxide thin film. The results are shown in Table 1.

Comparative Example 2:
In Example 1, the silica used in the manufacturing process of the coating liquid for forming a silicon oxide thin film was changed to chain silica (product “Snowtex OUP” manufactured by Nissan Chemical Industries, Ltd.), and 0.007 wt% A coating solution for forming a silicon oxide thin film was produced in the same manner as in Example 1 except that the same amount of pure water was used instead of the hydrochloric acid aqueous solution. And it carried out similarly to Example 1, obtained PET with a silicon oxide thin film of thickness 100nm, and evaluated the adhesiveness of the silicon oxide thin film. The results are shown in Table 1.

Comparative Example 3:
In Example 1, the silica used in the manufacturing process of the coating liquid for forming a silicon oxide thin film was changed to chain silica (product “Snowtex OUP” manufactured by Nissan Chemical Industries, Ltd.), and “KBM22” 50 parts by mass A silicon oxide thin film forming coating solution was produced in the same manner as in Example 1 except that 200 parts by mass of “silicate MS51” were changed to 150 parts by mass of “KBM22” and 100 parts by mass of “silicate MS51”, respectively. . The ratio of multimers in the bifunctional hydrolyzable silane compound is 40% by weight. And it carried out similarly to Example 1, obtained PET with a silicon oxide thin film of thickness 100nm, and evaluated the adhesiveness of the silicon oxide thin film. The results are shown in Table 1.

Claims (4)

  A method for producing a binder liquid for forming a silicon oxide thin film comprising a reaction composition by hydrolyzing and condensing a hydrolyzable silane compound, comprising a bifunctional hydrolyzable silane compound, at least 50% by weight of A hydrolyzable silane compound that is a multimer is used, and in the absence of silica particles, an aqueous acid catalyst solution is continuously dropped into a hydrophilic solvent solution in which the hydrolyzable silane compound is dissolved under stirring conditions. A process for producing a binder liquid for forming a silicon oxide thin film, characterized by carrying out a reaction.   The production method according to claim 1, wherein the multimer of the hydrolyzable silane compound is a multimer having an average multimerization degree n2 to 100 composed of tetramethoxysilane.   The production method according to claim 1 or 2, wherein the acid concentration of the acid catalyst aqueous solution is 0.01 to 0.001 wt%.   The manufacturing method of the coating liquid for silicon oxide thin film formation characterized by mixing the binder liquid obtained by the manufacturing method in any one of Claims 1-3, and a silica particle.