JP2012239997A - Method for manufacturing photoelectric conversion apparatus with anti-reflection film, and method for diagnosing coating characteristic of film forming composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for quickly and easily determining whether a film without unevenness can be formed by evaluating a film forming composition and the condition of a glass surface which is a film forming surface in the case of applying a large volume (30 ml/mor more) of a lean film forming composition (with a solid concentration of less than 0.5%) to the film forming surface using a spray method.SOLUTION: A uniform film can be formed when satisfying inequalities of 0<θ≤10 and 0≤S≤-θ+45, wherein S (mN/m) is surface tension to air and θ(°) is a contact angle of pure water to a glass surface by a drop method of the film forming composition.

Description

  The present invention provides a method for producing a photoelectric conversion device with an antireflection film for forming a uniform coating when a coating is formed by spray-coating a film-forming composition on the light incident surface of the photoelectric conversion device, and The present invention relates to a method for diagnosing coating properties of a film forming composition.

  The antireflection film is applied to various optical devices as means for suppressing surface reflection. In particular, in the field of solar cells, there have been various attempts to apply antireflection processing to the light incident surface of the solar cell in order to improve output. Among them, the sol-gel method is a method for forming an antireflection film having low production cost and excellent production compatibility. For example, Patent Document 1 discloses that a titania-silica film is formed on a substrate by a sol-gel method to develop an antireflection function. Using the amorphous titanium peroxide and silicon alkoxide as starting materials, a film-forming composition containing a metal-containing anatase-type titanium oxide, a silicon compound, and a thermally decomposable compound is prepared. It is disclosed that a low-reflective substrate can be made by using.

  By the way, when forming a film by applying the film forming composition to the substrate, not only the physical properties of the film forming composition but also the surface of the substrate on which the film is formed (hereinafter referred to as the film forming surface). Whether the coating can be applied uniformly and uniformly depends on the surface properties such as wettability. In particular, when the main solvent is a water film-forming composition, a uniform film can be formed evenly when the hydrophilicity of the surface is high. In order to increase the hydrophilicity of the surface, it is effective to clean the surface, and various surface cleaning methods and surface treatment methods and apparatuses for the same have been proposed so far.

JP 2009-212435 A

As described above, a composition for forming a film mainly containing titania-silica as a main component has been known using amorphous titanium peroxide and silicon alkoxide as starting materials. However, since titanium peroxide is an unstable substance, the physical properties of the film obtained vary greatly depending on the production conditions and the storage conditions after production, for example, temperature. In addition, polycondensation of a partially hydrolyzed condensate of silicon alkoxide, which is a silica component, also proceeds under storage conditions. In addition, the wettability of the surface of the film formation surface changes from moment to moment depending on the pretreatment method and the subsequent exposure to the atmosphere, which affects the ease of film formation. In particular, when a film is formed using a spray method, a very dilute composition for forming a film (solid content concentration of less than 0.5%) is applied in large quantities on the film forming surface (30 ml / m ² ) due to process restrictions. As described above, since the necessity arises, the film unevenness greatly varies depending on the state of the film forming composition and the film forming surface.

In fact, the inventor has made various attempts to form a film using the above-described composition for forming a film mainly composed of titania / silica. However, the method for preparing and storing the composition for forming a film, and pretreatment of the film-forming surface Depending on the atmospheric exposure after the pretreatment, a film with unevenness was sometimes formed. This causes the following problems. That is, in the case where a film is formed on the light incident surface of the photoelectric conversion device, the appearance of the film is observed after the film is formed, and it is possible to determine the presence or absence of unevenness for the first time. There is a problem of time. Therefore, even when a large amount of a coating film-forming composition (solid content concentration of less than 0.5%) is applied to the film-forming surface using a spray method (30 ml / m ² or more), the film-forming composition is used. In addition, there is a need for a method for evaluating the state of the film forming surface and quickly and easily determining whether a uniform film can be formed.

Therefore, in the present invention, even when a large amount of coating composition (solid content concentration of less than 0.5%) is applied to the coating surface using a spray method (30 ml / m ² or more), It is an object of the present invention to provide a method for evaluating a forming composition and a state of a film-forming surface and quickly and easily determining whether a uniform film can be formed.

  The inventors diligently studied the film forming conditions that affect the presence or absence of unevenness from the relationship between the surface tension of the film forming composition liquid and the film forming composition and the contact angle with respect to the film forming surface of pure water. First, prior to describing the problem solving means, the outline of the difference between the present invention and the conventional similar known technique will be outlined.

  Various studies have been made in the field of transfer technology such as printers regarding the influence of the surface tension of the film-forming composition liquid and film-forming composition and the contact angle of the film-forming composition liquid and film-forming composition on the substrate surface with respect to coating. Has been. For example, regarding the surface tension of the ink in the ink jet technology, “the surface tension of the ink affects the state of meniscus formation in the nozzle and the permeability in the media. Depending on the purpose, it is desirable to actively use a surfactant. It is generally performed to adjust the surface tension within the range of “(Inkjet), edited by Masahiko Fujii, edited by Japanese Imaging Society, Tokyo Denki University Press, September 2008, 1st edition, p112”.

  Japanese Patent Application Laid-Open No. 2003-41192 discloses a coating agent for transfer under various conditions after conducting various studies on the contact angle of the coating material for transfer to the substrate surface and the surface tension of the coating agent for transfer. When the surface tension in the stationary state and the contact angle of the transfer coating material with respect to the substrate surface are in a specific range, it is shown that the transfer coating material is less likely to cause film thickness unevenness and repellency.

However, these known technical contents are fundamentally different in technical idea from the present invention. That is, the evaluation of the surface tension and contact angle in the transfer technology field is for controlling the blurring of the transferred material, while the present invention is essentially applied to the surface of the photoelectric conversion device where liquid penetration cannot occur. In order to apply the film-forming composition uniformly without any gaps, the surface tension and the contact angle were evaluated and studied, leading to the invention. Further, a transfer coating in the transfer technology field is an ink containing a pigment or the like, and it is not assumed that at least 20 ml / m ² or more is applied to an object to be transferred. It was conceived when studying film formation when a large amount of a composition for forming (solid content concentration of less than 0.5%) was applied (30 ml / m ² or more), and reached a completely different technical viewpoint. It is a thing.

A first aspect of the present invention is a glass for a photoelectric conversion device comprising a glass substrate and a film-forming composition having a solid content concentration of 0.5% or less containing titanium oxide, silicon oxide and an organosilicon surfactant. A method for producing a photoelectric conversion device with an antireflection film comprising a step of applying a surface of 30 ml / m ² or more to the surface by a spray method,
The surface tension S (mN / m) to air by the dropping method of the film forming composition and the contact angle θ (°) of pure water to the glass surface are 0 <θ ≦ 10 and 0 ≦ S ≦ After undergoing a step of confirming that the relationship of −θ + 45 is satisfied,
It is a manufacturing method of the photoelectric conversion apparatus with an antireflective film provided with the process apply | coated by the said spray method.

In the second aspect of the present invention, it is possible to uniformly apply a film forming composition having a solid content concentration of 0.5% or less to a glass surface of a photoelectric conversion device including a glass substrate by a spray method of 30 ml / m ² or more. As an index for determining the surface tension S (mN / m) with respect to the air by the dropping method of the film-forming composition and the contact angle θ (°) of pure water with respect to the glass surface, the following (A) And a method for diagnosing coating properties of the film-forming composition, which confirms whether or not the inequality of (B) is satisfied;
(A) 0 <θ ≦ 10,
(B) 0 ≦ S ≦ −θ + 45.

  A third aspect of the present invention is the coating property diagnostic method, wherein the film-forming composition is a film-forming composition comprising amorphous titanium peroxide, silicon oxide, and an organosilicon surfactant. .

The fourth aspect of the present invention is the coating property diagnostic method as described above, further confirming whether or not the following inequality (A ′) is satisfied;
(A ′) 4 <θ ≦ 10.

In the fifth aspect of the present invention, the coating property diagnosis method described above further confirms whether or not the following inequality (B ′) is satisfied;
(B ′) 10 ≦ S ≦ −θ + 45.

The sixth aspect of the present invention is the coating property diagnostic method as described above, further confirming whether the following inequalities (A ′) and (B ′) are satisfied;
(A ′) 4 <θ ≦ 10,
(B ′) 10 ≦ S ≦ −θ + 45.

  According to the method of manufacturing a photoelectric conversion device with an antireflection film according to the present invention, it is possible to determine the presence or absence of unevenness without forming a film before forming a film, so that the yield rate decreases and the process time associated with appearance observation increases. The problem of conversion can be avoided.

  By using the method for diagnosing coating characteristics according to the present invention, it is possible to determine the presence or absence of unevenness without forming a film, so that it is possible to avoid problems such as a decrease in yield rate and a longer process time associated with appearance observation. .

(Diagnosis method)
The present invention is a coating property diagnostic method for judging whether or not a uniform film can be formed on the surface of a photoelectric conversion device (actually, on the glass surface side) with the composition for forming a film. There are many types of photoelectric conversion devices depending on their constituent materials and structures, but any of them can be applied. Particularly useful for thin-film solar cells formed on a light-transmitting substrate and having a structure in which light enters from the surface of the light-transmitting substrate where the thin-film solar cell is not formed (super straight structure). It is. The coating can have various functions depending on its composition. Examples thereof include an antireflection function, an antistatic function, a wavelength conversion function, a photocatalytic function, and an antifouling function. In the case of the antireflection function, the film-forming composition can form a film having a refractive index lower than that of the translucent substrate. The coating here refers to a surface coating obtained by applying a composition for forming a material coating on the surface of a photoelectric conversion device, followed by drying and baking.

  Here, the term “uniform” means that the standard deviation of the film thickness is within 20% of the average value of the film thickness when the film thickness is measured at a plurality of locations, preferably 10 locations or more so as to cover the surface on which the film is formed as much as possible. Say something.

  The film thickness is determined by a commonly used film thickness measurement method. For example, spectroscopic ellipsometry, cross-sectional measurement using a transmission electron microscope (TEM), a step meter, or the like is used. In particular, spectroscopic ellipsometry is a film thickness measurement method more suitable for the purpose of the present invention because it can measure the film thickness quickly and easily.

  The coating property diagnosis herein refers to a uniform film on the surface of a photoelectric conversion device when a film is formed using a given film forming composition, a given photoelectric conversion device surface, and a given film formation device. It gives an answer as to whether or not it can be formed.

(Process for forming a film)
The process of forming a film that is the object of diagnosis is a process in which a film forming composition having a spray solid content concentration of 0.5% or less is applied to the surface of the photoelectric conversion device (actually the glass surface side) by 30 ml / m ² or more. is there. The reason why the solid content concentration of the film-forming composition is limited to 0.5% or less is that the present invention uses a film-forming composition liquid / film-forming composition having an extremely low solid content concentration due to restrictions on the spray method. This is because this is a method for diagnosing coating characteristics in some cases. In addition, the reason why the coating amount applied to the surface of the photoelectric conversion device (actually the glass surface side) is limited to 30 ml / m ² or more is that a large amount of the film-forming composition is applied to the surface of the photoelectric conversion device due to the restriction of the spray method. This is because it is a method for diagnosing coating properties when applied to the surface.

(Coating composition)
As the film forming composition, a film forming composition containing at least amorphous titanium peroxide, silicon oxide and an organosilicon surfactant is preferably used.

Commercially available aqueous solutions of titanium peroxide include (1) Amorphous titanium peroxide aqueous solution (SP) manufactured by Sustainable Technology Co., Ltd. (2) Photooxidized positively charged metal oxide doped amorphous titanium peroxide aqueous solution (SPZ high function) Type), (3) Amorphous modified titanium peroxide + carbohydrate complex aqueous solution (DaSH), (4) Asuka Riken Co., Ltd. (4) Fluorescence, (5) ) Tsuruclean (registered trademark) grade A-TS-1, (6) Tsuruclean (registered trademark) grade A-TS-2, and (7) PTA aqueous solution manufactured by Sakai Corporation.
There are the following methods for producing amorphous titanium peroxide.

(Manufacturing method 1)
A basic aqueous solution is added to the soluble inorganic titanium compound aqueous solution. When the resulting pale bluish white, amorphous ortho-titanium is washed and separated and then treated with an oxidizing agent, the amorphous titanium peroxide liquid of the present invention is obtained.

Soluble inorganic titanium compounds include titanium chelate, acetate titanium, titanium sulfate,
Examples thereof include titanium tetrachloride. Examples of the basic aqueous solution include sodium hydroxide, potassium hydroxide, ammonia, tetraalkylammonium hydroxide and the like. The reaction of adding a basic aqueous solution to a soluble inorganic titanium compound aqueous solution is a neutralization reaction and involves a large exotherm. This is because when the reaction proceeds at a high temperature, the reaction from orthotitanic acid to metatitanic acid proceeds.

  Any oxidizing agent may be used as long as it can oxidize titanium dioxide to titanium peroxide, but hydrogen peroxide is particularly preferable. When hydrogen peroxide water is used as the oxidizing agent, the concentration of hydrogen peroxide is preferably 30 to 40% because the reaction is accelerated. It is preferred to cool the titanium hydroxide before peroxolation. This is because the peroxoation reaction is an exothermic reaction and the reaction needs to proceed mildly. The cooling temperature at that time is preferably 1 to 5 ° C.

(Manufacturing method 2)
An appropriate amount of titanium alkoxide, alcohol, water and catalyst is mixed to conduct hydrolysis and polycondensation reaction. Furthermore, an amorphous type titanium peroxide liquid can be obtained by adding an oxidizing agent.

  Examples of the titanium alkoxide include tetraethoxy titanium, tetramethoxy titanium, tetrapropoxy titanium, and tetrabutoxy titanium. Examples of the alcohol include methanol, ethanol, n-propanol, and isopropanol. Any oxidizing agent may be used as long as it can oxidize titanium dioxide to titanium peroxide, but hydrogen peroxide is particularly preferable. When hydrogen peroxide water is used as the oxidizing agent, the concentration of hydrogen peroxide is preferably 30 to 40% because the reaction is accelerated. It is preferred to cool the titanium hydroxide before peroxolation. This is because the peroxoation reaction is an exothermic reaction and the reaction needs to proceed mildly. The cooling temperature at that time is preferably 1 to 5 ° C.

  As the shape of titanium oxide, titanium oxide commercially available in the form of particles, powder, or sol can be used.

  The molar concentration of Ti can be changed from time to time depending on the desired antireflection properties and durability. 0.0001 to 0.01 mol / L is preferable, and 0.002 to 0.008 mol / L is more preferable. This is because when the amount of Ti is small, the surface hydrophilizing effect is not achieved. This is because when the amount of Ti is large, the refractive index of the film becomes high and the function as an antireflection film is not achieved.

Silicon oxide has the general formula _{SiR n (OR ') 4-} n (R' and R is an alkyl group having 1 to 5 carbon atoms, n represents a natural number of 0 to 3) a hydrolyzate of silicon alkoxide represented by and / Or a partial hydrolyzate. Furthermore, it is also possible to use a liquid that has been subjected to a condensation polymerization reaction using an acid catalyst or a base catalyst. Further, silica fine particles may be partially added. This is because the addition of silica fine particles increases the film strength.

  The molar concentration of Si can be changed from time to time depending on the desired antireflection properties and durability. 0.001-0.1 mol / L is preferable and 0.02-0.05 mol / L is further more preferable. This is because when the amount of Si is small, the amount of Ti is relatively large, so that the refractive index of the film becomes high and the function as an antireflection film is not achieved. Further, when the amount of Si is large, the amount of Ti is relatively small, so that the surface hydrophilizing effect is not achieved. Moreover, it is also because it becomes difficult to form a film without unevenness because the solution becomes high in concentration and handling at the time of film formation becomes difficult.

  As the organosilicon surfactant, commercially available various silicone surfactants can be used as appropriate. Specifically, TSF4445, TSF4446 (GE Toshiba Silicone Co., Ltd.), KP series (Shin-Etsu Chemical Co., Ltd.), SH200, SH3746M, DC3PA, ST869A (Toray Dow Corning Co., Ltd.), etc. should be used. Can do. As the silicone, those having an alkyl silicate structure or a polyether structure in the molecule, or those having both an alkyl silicate structure and a polyether structure are preferable. Here, the alkyl silicate structure refers to a structure in which an alkyl group is bonded to a silicon atom of a siloxane skeleton. On the other hand, the polyether structure means a structure having an ether bond, such as polyethylene oxide, polypropylene oxide, polytetramethylene oxide, polyethylene oxide-polypropylene oxide block copolymer, polyethylene polytetramethylene glycol copolymer, polytetramethylene. Examples thereof include a molecular structure such as a glycol-polypropylene oxide copolymer. Among these, a polyethylene oxide-polypropylene oxide block copolymer is preferable from the viewpoint of controlling the surface tension. As the organosilicon compound, silicone having both alkyl silicate structure and polyether structure in the molecule is particularly preferable. Specifically, polyether-modified silicone such as polyether-modified polydimethylsiloxane is suitable.

  More preferably, the film-forming composition of the present invention is further doped with one or more elements selected from copper, zirconium, tin, zinc, antimony and silver. This is because the addition of these metals exhibits antifouling, antibacterial and antistatic functions.

  The method for doping these metals can be achieved by adding a metal oxide or a metal salt during the synthesis of the above titanium oxide and silicon oxide. Examples of commercially available metal-doped titanium oxide include SPZ series (Sustainable Technology Co., Ltd.).

  Examples of the metal oxide or metal salt include the following. Copper: Copper hydroxide, copper chloride, copper sulfate, copper nitrate, copper acetate, copper oxide. Zirconium: Zirconium hydroxide, zirconium dichloride, zirconium tetrachloride, zirconium sulfate, zirconium nitrate, zirconium acetate, zirconium oxide. Tin: Tin hydroxide, tin chloride, tin sulfate, tin nitrate, tin acetate, tin oxide. Zinc: Zinc hydroxide, zinc chloride, lead sulfate, zinc nitrate, zinc acetate, zinc oxide. Antimony :: antimony hydroxide, antimony chloride, antimony sulfate, antimony nitrate, antimony acetate, antimony oxide. Silver: Silver hydroxide, silver chloride, silver sulfate, silver nitrate, silver acetate, silver oxide.

  Metal doping can be performed in a timely manner in the production process of the film-forming composition, but is preferably performed during the synthesis of titanium oxide. This is because removal of by-products can be easily performed by washing with water.

The following is mentioned as an example of the specific manufacturing method which doped the metal.
One or more of copper chloride, zirconium chloride, zinc chloride, tin chloride, antimony chloride, and silver chloride is added to the titanium tetrachloride compound aqueous solution. A basic aqueous solution such as an aqueous ammonia solution is added to this solution. When the resulting pale bluish white, amorphous titanium hydroxide is washed and separated and then treated with hydrogen peroxide, the metal-doped amorphous titanium peroxide liquid of the present invention is obtained. When ammonia is used in a basic aqueous solution, the by-product is ammonium chloride, which is water-soluble. Therefore, since ammonium chloride is dissolved in the step of washing titanium hydroxide, metal-doped amorphous titanium peroxide with few impurities can be obtained.

  The value of the molar concentration of Si / the molar concentration of Ti is preferably 1 to 30, and more preferably 5 to 20. If the Si molar concentration / Ti molar concentration value is too large, the surface hydrophilization effect by titanium oxide is not sufficient, and if it is too small, the refractive index of the film increases and the function as an antireflection film is not achieved. is there.

  As a dilution medium of the film forming composition, various alcohols (methanol, ethanol, 1-propanol, 2-propanol, n-butanol, isobutanol) are suitably used in addition to pure water. Further, a liquid in which two or more of these media are mixed may be used. Of these media, pure water is preferred. This is because an organic medium such as alcohol is apt to volatilize, and a large amount of organic vapor is generated in the spray method, resulting in poor production suitability.

  The surface tension of the film-forming composition mainly depends on the amount of surfactant added and the degree of surfactant deactivation. More specifically, (1) the higher the concentration of the organosilicon surfactant, the lower the surface tension, and saturation at a certain concentration or more. (2) The surface tension starts from several days after mixing the organosilicon surfactant. The surface tension increases over a month and then saturates. (3) The lower the concentration of the organosilicon surfactant, the slower the surface tension increases. The surface tension changes in the range of 20 mN / m to 70 mN / m depending on these conditions.

(Diagnostic criteria)
In the diagnosis of the present invention, parameters of the surface tension S (mN / m) to air by the dropping method of the film forming composition and the contact angle of pure water to the glass surface are used. For the surface tension, various methods that have been put to practical use, such as a capillary rise method, a hanging ring method, and a dropping method, can be used. In particular, the use of the dropping method is a surface tension measuring method suitable for the purpose of the present invention, which requires quick and simple. The surface tension against air by the dropping method according to the present invention was measured three times using a contact angle meter (PCA-1 (manufactured by Kyowa Interface Science)), and the arithmetic average value was used. The temperature at that time is 25 degrees ± 1 degree.

  The contact angle of pure water with respect to the glass surface of the photoelectric conversion device can be measured by various measuring devices based on the wettability test method for the surface of the substrate glass in JIS R 3257.

When S and θ satisfy the following (A) and (B), it is determined that a uniform film can be formed.
(A) 0 <θ ≦ 10
(B) 0 ≦ S ≦ −θ + 45
The range of θ is more preferably 4 <θ ≦ 10. This is because a contact angle of 4 ° or less is generally difficult to measure, and even if a contact angle of 4 ° or less is obtained in the measurement, there is a high probability that there is a problem in measurement. This is for the purpose of the invention.

  The range of S is more preferably 10 ≦ S ≦ −θ + 45. This is because, in general, liquids having a surface tension of 10 mN / m or less are rare, and even if a surface tension of 10 mN / m or less is obtained in measurement, there is a high probability that there is a problem in measurement, and quick and simple is required. This is for the purpose of the present invention.

  In particular, it is more preferable that 4 <θ ≦ 10 for the range of θ and 10 ≦ S ≦ −θ + 45 for the range of S. This is because it can be expected that the diagnosis of the present invention can be performed without any problem in measurement of the surface tension and the contact angle.

  In addition, said description content can be used as it is also to the following 1st-6th of this invention.

A first aspect of the present invention is a glass for a photoelectric conversion device comprising a glass substrate and a film-forming composition having a solid content concentration of 0.5% or less containing titanium oxide, silicon oxide and an organosilicon surfactant. A method for producing a photoelectric conversion device with an antireflection film comprising a step of applying a surface of 30 ml / m ² or more to the surface by a spray method,
The surface tension S to the air by the dropping method of the film forming composition and the contact angle θ of pure water to the glass surface satisfy the relationship of 0 <θ ≦ 10 and 0 ≦ S ≦ −θ + 45. After going through the process of checking
It is a manufacturing method of the photoelectric conversion apparatus with an antireflective film provided with the process apply | coated by the said spray method.

In the second aspect of the present invention, it is possible to uniformly apply a film forming composition having a solid content concentration of 0.5% or less to a glass surface of a photoelectric conversion device including a glass substrate by a spray method of 30 ml / m ² or more. As an index for judging the surface tension S (mN / m) of air by the dropping method of the film forming composition and the contact angle θ (°) of pure water with respect to the glass surface, the following (A) and ( A method for diagnosing the coating property of the composition for forming a film, which confirms whether or not the inequality of B) is satisfied;
(A) 0 <θ ≦ 10,
(B) 0 ≦ S ≦ −θ + 45.

  A third aspect of the present invention is the coating property diagnostic method, wherein the film-forming composition is a film-forming composition comprising amorphous titanium peroxide, silicon oxide, and an organosilicon surfactant. .

The fourth aspect of the present invention is the coating property diagnostic method as described above, further confirming whether or not the following inequality (A ′) is satisfied;
(A ′) 4 <θ ≦ 10.

In the fifth aspect of the present invention, the coating property diagnosis method described above further confirms whether or not the following inequality (B ′) is satisfied;
(B ′) 10 ≦ S ≦ −θ + 45.

The sixth aspect of the present invention is the coating property diagnostic method as described above, further confirming whether the following inequalities (A ′) and (B ′) are satisfied;
(A ′) 4 <θ ≦ 10,
(B ′) 10 ≦ S ≦ −θ + 45.

(Evaluation liquid 1)
Partial hydrolyzate of silica sol liquid (partial condensate of tetraethyl silicate, Si _n O _n-1 (OC ₂ H ₅ ) _{2 (n + 1),} n = 4 to 6; (Tama Chemical Industry Co., Ltd.)), Copper-doped titania aqueous dispersion: Z18-1000 Super A (Sustainable Technology Co., Ltd.) is mixed, diluted with pure water, and the molar concentrations of Si and Ti in the solution are 0.025 mol / L and 0.0025 mol, respectively. did. When the solid content concentration of the evaluation liquid was measured using an infrared moisture meter, it was 0.45 wt%.

(Evaluation liquid 2)
Organosilicone-based surfactant: ZB (Sustainable Technology Co., Ltd.) was prepared in the same manner as evaluation liquid 1 except that the amount added was 3 wt% (referred to as evaluation liquid 2). did.

(Evaluation liquid 3)
Organosilicone-based surfactant: ZB (Sustainable Technology Co., Ltd.) was prepared in the same manner as Evaluation Solution 1 except that the amount added was 5 wt% (Evaluation Solution 3). did.

(Evaluation liquid 4)
Organosilicone surfactant: ZB (Sustainable Technology Co., Ltd.) was used to prepare a film-forming composition (Evaluation Solution 4) in the same manner as Evaluation Solution 1 except that the amount added was 7 wt%. did.

(Evaluation liquid 5)
Organosilicon-based surfactant: Z-B (Sustainable Technology Co., Ltd.) was prepared in the same manner as Evaluation Solution 1 except that the amount added was 10 wt% (Evaluation Solution 10). did.

(Surface tension against air by dropping method of evaluation liquid)
The surface tension against air by the dropping method immediately after the production of the evaluation liquids 1 to 5 was 47, 32, 31, 28, and 26 mN / m, respectively. The surface tensions 7 days after the preparation of the evaluation solutions 1 to 5 were 64, 43, 35, 31, and 29 mN / m, respectively. Therefore, it can be seen that the surface tension decreases as the amount of the organosilicon surfactant increases. Moreover, it turns out that surface tension falls with progress of time after liquid preparation. And it turns out that the liquid of the arbitrary surface tensions to 25-65 mN / m can be produced by optimizing the quantity of organosilicon type surfactant, and the time after liquid preparation.

(Evaluation board 1)
The white plate glass was polished and cleaned using an abrasive (cerium oxide ultrafine particles). Furthermore, the surface hydrophilizing agent process was performed. The contact angle of pure water to the white glass immediately after the treatment was 3.5 °. The contact angle 3 days after the treatment was 25 °. In addition, surface tension was measured 3 times using the contact angle meter (PCA-1 (made by Kyowa Interface Science)), and the arithmetic mean value was used. Therefore, it can be seen that by controlling the surface treatment and the atmospheric exposure time after the treatment, a white plate glass having an arbitrary contact angle between 4 ° and 25 ° of pure water with respect to the white plate glass can be produced.

(Example)
A thin-film silicon solar cell having a light incident surface made of glass is prepared, and the contact angle of the light incident surface with respect to pure water is 5 °, 7 °, 9 °, and 11 ° by the same treatment as the surface treatment on the evaluation substrate 1 described above. A thin film silicon solar cell having an angle of 13 ° was prepared. Also, evaluation liquids having surface tensions of 32, 34, 36, 38, 40, and 42 mN / m were prepared by adjusting the elapsed time after the evaluation liquids 1 to 5 were prepared. And the liquid which has each surface tension was apply | coated with respect to each thin film silicon solar cell. The coating was performed using a spray method under coating conditions such that 45 ml / m ² . The applied thin film silicon solar cell was immediately fired and dried at 90 ° C. for 15 minutes in an annealing oven.

  Ten sheets were produced for each (θ, S) combination. Each coating film was subjected to spectroscopic ellipsometry to measure 25 × 5 × 5 and analyze the film thickness. Table 1 shows the unevenness for each (θ, S) combination. Here, in all 10 sheets, a film is formed without any unevenness in appearance, and when the standard deviation of the film thickness is within 20% of the average value of the film thickness, it is determined that a uniform film is formed. In Table 1, “◯” is shown. When the standard deviation of the film thickness is larger than 20% of the average value of the film thickness in 1 to 9 of the 10 thin film silicon solar cells, it is determined that a uniform film may not be formed. It was described. In all 10 thin film silicon solar cells, when the standard deviation of the film thickness was larger than 20% of the average value of the film thickness, it was judged that a uniform film was not formed.

  Whether or not a uniform film is formed can be determined by whether or not the ranges of θ and S are included in 0 <θ ≦ 10 and 0 ≦ S ≦ −θ + 45, respectively.

Claims (6)

30 ml / m ² or more of a film-forming composition having a solid content concentration of 0.5% or less containing titanium oxide, silicon oxide, and organosilicon surfactant on the glass surface of a photoelectric conversion device including a glass substrate A method of manufacturing a photoelectric conversion device with an antireflection film including a step of applying by a spray method,
The surface tension S (mN / m) to air by the dropping method of the film forming composition and the contact angle θ (°) of pure water to the glass surface are 0 <θ ≦ 10 and 0 ≦ S ≦ After undergoing a step of confirming that the relationship of −θ + 45 is satisfied,
The manufacturing method of the photoelectric conversion apparatus with an antireflection film provided with the process apply | coated by the said spray method. As an index for determining whether or not a film forming composition having a solid content concentration of 0.5% or less can be uniformly applied to a glass surface of a photoelectric conversion device including a glass substrate by a spray method of 30 ml / m ² or more, Whether the surface tension S (mN / m) to air by the dropping method of the film forming composition and the contact angle θ (°) of pure water to the glass surface satisfy the following inequalities (A) and (B) A method for diagnosing coating properties of the composition for forming a film,
(A) 0 <θ ≦ 10,
(B) 0 ≦ S ≦ −θ + 45. The method for diagnosing coating properties according to claim 2, wherein the film-forming composition is a film-forming composition comprising amorphous titanium peroxide, silicon oxide, and an organosilicon surfactant. Furthermore, it is confirmed whether the following inequality (A ') is satisfy | filled, The coating characteristic diagnostic method of Claim 2 or 3;
(A ′) 4 <θ ≦ 10. Furthermore, the coating characteristic diagnostic method of any one of Claims 2-4 which confirms whether the following inequality (B ') is satisfy | filled;
(B ′) 10 ≦ S ≦ −θ + 45. Furthermore, it is confirmed whether the following inequalities (A ') and (B') are satisfied.
(A ′) 4 <θ ≦ 10,
(B ′) 10 ≦ S ≦ −θ + 45.