WO2014192668A1 - Drying apparatus and drying method - Google Patents

Abstract

The present invention suppresses a decrease in condensation drying efficiency, and reduces the failure of a coating film. A drying apparatus (1) is provided with a condenser plate (11) facing a coating film of a substrate (f1), and dries said coating film by condensing solvent vapor from the coating film using the condenser plate (11). The coating film contains a silicon compound that produces silane gas, and is provided with a flat recovery member (13), which is positioned so as to face the coating film on the substrate (f1), as a recovery means for recovering the silane gas produced from the coating film before the condenser plate (11) dries.

Description

Drying apparatus and drying method

The present invention relates to a drying apparatus and a drying method.

In an electronic device such as a liquid crystal display element, an organic electroluminescence element, or a solar cell, a gas barrier film that shields permeation of a gas such as water and oxygen is used in order to improve storage stability.
In the gas barrier film, a metal or metal oxide film having low gas permeability is provided as a gas barrier layer on a substrate such as a resin film.

Conventionally, a method of forming a gas barrier layer by depositing a metal or a metal oxide on a substrate by a plasma CVD method (Chemical Vapor Deposition) is also known.
There is also known a method of forming a gas barrier layer by applying a coating solution containing a silicon compound called polysilazane as a main component on a substrate and then converting it to a ceramic such as silicon oxide.

As the film thickness of the gas barrier layer increases, the gas barrier property increases. However, if the coating film containing a silicon compound is simply thickened, cracks are likely to occur after conversion to ceramics.
In order to suppress cracking while obtaining a high gas barrier property, a coating solution containing a silicon compound is applied by a wet process to form a coating film, and a process of performing a modification treatment of irradiating vacuum ultraviolet rays is repeated twice or more, A technique for laminating a plurality of gas barrier layers on a substrate is disclosed (for example, see Patent Document 1).

Since the coating film formed by the wet process contains a large amount of solvent, it is necessary to dry the coating film before the modification treatment. However, it is known that the coating film formed by the wet process is likely to be uneven in drying and it is difficult to make the film thickness uniform.
As a cause of drying unevenness, an organic solvent is generally used for the coating solution, and the viscosity tends to be low. In particular, a coating solution containing a silicon compound tends to have a low viscosity of 100 mPa · s or less. Although it is conceivable to use a thickener, the thickener is not preferable because it can cause deterioration in gas barrier properties.

As a method for drying a coating film applied by a wet process, a condensation drying process is performed in which a condensing plate faces the coating film surface with a narrow gap, and the vapor of the solvent from the coating film is condensed and dried on the condensing surface of the condensing plate. Has been proposed (see, for example, Patent Document 2).
According to this condensation drying process, precise drying can be performed with a simple operation of controlling the distance between the coating film surface and the condensation surface and the temperature of the coating film surface and the condensation surface without using convection heat transfer. it can.

JP 2009-255040 A Special table 2003-524847

However, the silicon compound contained in the coating film of the gas barrier layer reacts with oxygen or water in the air to generate a highly reactive silane-based gas. When the silane-based gas is generated during the condensation drying, the solvent is prevented from condensing and the drying efficiency is lowered.

In addition, the silane-based gas reacts with moisture in the atmosphere and the silicon compound is deposited, and easily adheres to the condensation surface.
When a minute slit is formed on the condensing surface in order to discharge the solvent droplets adhering to the condensing surface, the slit is buried by the deposited silicon compound. Therefore, the capillary force of the slit for discharging the solvent is lost, the discharge of the solvent is hindered, and the drying efficiency is also lowered.
Furthermore, the silicon compound adhering to the condensing plate peels off and adheres to the coating film, increasing the failure of the coating film.

An object of the present invention is to suppress a decrease in drying efficiency of condensation drying and to reduce the failure of the coating film.

According to the invention of claim 1,
A drying apparatus comprising a condensing plate facing a coating film on a substrate, condensing the solvent vapor from the coating film with the condensing plate, and drying,
The coating film contains a silicon compound that generates a silane-based gas,
Provided is a drying apparatus comprising a recovery means for recovering a silane-based gas generated from the coating film before drying by the condenser plate.

According to invention of Claim 2,
The drying apparatus according to claim 1, wherein the collection unit is a planar collection member that is disposed to face the coating film on the substrate.

According to invention of Claim 3,
The drying apparatus according to claim 2, wherein the recovery member is heated.

According to invention of Claim 4,
The drying apparatus according to any one of claims 1 to 3, wherein a solid content ratio of the coating film after the silane-based gas is recovered by the recovery means is 30% by mass or more. .

According to the invention of claim 5,
The drying apparatus according to any one of claims 1 to 4, wherein the silicon compound is a silicon compound having a polysilazane skeleton.

According to the invention of claim 6,
A condensing plate facing the coating film on the substrate is a drying method for condensing and drying the solvent vapor from the coating film,
A drying method characterized in that when a coating film containing a silicon compound that generates a silane-based gas is dried, the silane-based gas generated from the coating film is recovered by a recovery means before drying by the condenser plate. Provided.

According to the present invention, it is possible to reduce silane-based gas that is generated from the coating film during condensation drying and hinders condensation of the solvent. It can suppress that the deposit of a silane type gas adheres to a condensation plate, and the condensing effect | action of a condensation plate falls, and can suppress the fall of the drying efficiency of condensation drying. As the silane-based gas decreases, the amount of deposits adhering to the condensing plate also decreases, so that it is possible to reduce failures where the deposits peel off and adhere to the coating film.

It is a front view which shows the structure of the thin film forming apparatus with which the drying apparatus which concerns on this Embodiment was used. FIG. 2 is a cross-sectional view taken along line Z2-Z2 in FIG. FIG. 3 is a cross-sectional view taken along line Z1-Z1 in FIG. It is a front view which shows the example of the other collection | recovery means of silane type gas.

Hereinafter, embodiments of the drying apparatus and the drying method of the present invention will be described with reference to the drawings.

FIG. 1 shows a configuration of a thin film forming apparatus 100 in which the drying apparatus 1 according to the present embodiment is used.
FIG. 2 is a sectional view taken along line Z2-Z2 of FIG.
As shown in FIGS. 1 and 2, the thin film forming apparatus 100 forms a coating film f <b> 2 by applying a coating solution onto the substrate f <b> 1 by the coating apparatus 3, and dries the coating film f <b> 2 by the drying apparatus 1. A thin film is formed on the substrate f1.
The thin film forming apparatus 100 further includes a drying device 4 in order to remove the residual solvent. Further, the thin film forming apparatus 100 includes the reforming device 5 and can modify the coating film f2.

As shown in FIG. 1, the substrate f <b> 1 is sent to the coating device 3 by the unwinder 21, transported by the rollers 22 and 23, and wound by the winder 24.

The coating apparatus 3 applies a coating solution containing a solvent on the substrate f1 by a wet process. As a coating method of the coating device 3, for example, a casting method, an inkjet method, a spray method, a printing method, a slot method using a slit type die coater, an ESD (Electro Spray Spray Deposition) method, an ESDUS (Evaporative Spray Deposition A from Ultra-dilute Solution) ) Law.

As a method of coating on the substrate f1 that is continuously transported, a post-weighing type in which an application liquid is applied in excess of the amount necessary to form a coating film having a required film thickness, and then the excess is removed. A pre-weighing type in which a coating solution is applied in a necessary amount is known. Any coating method can be applied, but the pre-weighing type is preferable from the viewpoints of high accuracy, high speed, thin film, improved coating film quality, suitability for lamination, and the like. Moreover, a closed system is preferable from the viewpoints of suppressing the exposure of the coating liquid, suppressing the change in concentration, maintaining the cleanliness, and preventing the contamination of foreign matters. Therefore, among the above coating methods, a slot method using a slit type die coater and an ink jet method are preferable.

The drying device 1 is preferably installed immediately after the coating device 3 so that it can be dried immediately after the coating liquid is applied. By starting the drying immediately after the application, it is possible to prevent drying unevenness caused by the surrounding airflow or natural convection in the drying apparatus 1. Although it depends on the conveyance speed of the substrate f1, the time from the start of application to the start of drying is preferably within 30 seconds, and more preferably within 10 seconds.
In addition, airflow blocking means such as a blocking plate and a case is provided between the coating apparatus 3 and the drying apparatus 1 or airflow rectifying means such as a rectifying plate and a rectifying fan is provided to convection around the coating film f2. It can also be suppressed.

As shown in FIGS. 1 and 2, the drying apparatus 1 includes a condensing plate 11 that faces the coating film f2 on the substrate f1. The drying apparatus 1 condenses the vapor of the solvent contained in the coating film f2 by the condensing plate 11, and dries the coating film f2.
Further, the drying device 1 includes a heating device 12, a recovery member 13, and a heat roller 14.

The condensing plate 11 condenses the vapor of the solvent from the coating film f2 on the condensing surface 11a facing the coating film surface f2a.
The material of the condenser plate 11 can be selected as appropriate in consideration of thermal conductivity, weight, processability, processing accuracy, and resistance to solvents. Examples of the material of the condensing plate 11 include metals such as aluminum, copper, iron, and SUS (stainless steel) or alloys thereof, plastic, and wood. Of these, aluminum is preferred because of its excellent workability and thermal conductivity.

The condensing plate 11 may have a plurality of slits formed on the condensing surface 11a. The solvent condensed by the slit can be discharged from the condensing surface 11a, and a decrease in condensation efficiency due to the saturation of the solvent can be suppressed.
The slit may be formed in parallel with the transport direction y, or may be formed in parallel with the width direction x orthogonal to the transport direction y. The solvent condensed on the condensation surface 11a is transported by the capillary force of the slit and is discharged from the condensation surface 11a.
When providing a slit, it is good also as providing the side plate drooping from the side surface of the condensation plate 11, and collect | recovering the solvent discharged | emitted along the slit by the said side plate.

The condensing plate 11 may be subjected to a surface treatment on the condensing surface 11a in order to prevent contamination and efficiently discharge the condensed solvent.
For example, the condensation surface 11a can be subjected to water repellent treatment or hydrophilic treatment.

The heating device 12 heats the coating film f2 through the substrate f1 and promotes evaporation of the solvent.
The heating device 12 is disposed at a position facing the condenser plate 11 via the substrate f1.
Examples of the heating method of the heating device 12 include a heating method using hot air, infrared rays, ultraviolet rays, microwaves, electric resistance, and the like.

The recovery member 13 is recovery means for recovering the silane-based gas generated from the coating film f2 before the coating film f2 is condensed and dried by the condensing plate 11.
A silane-based gas refers to a gas containing silicon (Si) and having high reactivity with moisture (H ₂ O) or oxygen gas in the atmosphere. Examples of the silane-based gas include monosilane (SiH ₄ ), disilane (Si ₂ H ₆ ), dichlorosilane (SiH ₂ Cl ₂ ), trichlorosilane (SiHCl ₃ ), tetrachlorosilane (SiCl ₄ ), and tetrafluoride. silicon (SiF _4), and the like.

When the coating film f2 contains a silicon compound that generates a silane-based gas, the silane-based gas is generated from the coating film f2 even during condensation-drying, thereby preventing the condensation of the solvent, resulting in a decrease in drying efficiency. In addition, the silane-based gas that has come into contact with the condenser plate 11 precipitates, reducing the condensation action of the condenser plate 11 and increasing the number of failures in which the deposit adheres to the coating film f2.
The recovery member 13 recovers the silane-based gas generated from the coating film f2 before the condensation drying, thereby suppressing a decrease in the drying efficiency of the condensation drying and reducing a failure due to the deposit of the silane-based gas.

FIG. 3 is a cross-sectional view taken along the line Z1-Z1 of FIG.
As shown in FIGS. 1 and 3, the recovery member 13 has a planar shape and is disposed so as to face the coating film f <b> 2 on the substrate f <b> 1 upstream of the condensing plate 11 in the transport direction y.
When the silane-based gas is generated from the coating film f2, the silane-based gas reacts with water in the atmosphere and the silicon compound is deposited on the surface of the recovery member 13 and adheres thereto.

The recovery member 13 may be a plate shape, a sheet shape, or a disk shape as long as it is planar.
When the collection member 13 is in the form of a sheet, the roll body of the collection member 13 can be unwound and a silane gas can be attached thereto, and then wound up. Further, the endless collection member 13 can be wound around a roller and rotated.
When the collection member 13 is disk-shaped, the silane-based gas can be collected while rotating the disk-shaped collection member 13.
After the silane-based gas is sufficiently adhered to the recovery member 13, the recovery member 13 may be replaced to increase the efficiency of recovery of the silane-based gas.

The recovery member 13 can be made of a metal such as glass, aluminum, copper, iron, SUS, or an alloy thereof. Glass with high transparency is preferable because the degree of recovery of the silane-based gas can be visually determined.

The recovery member 13 is preferably heated in order to generate and recover as much silane-based gas as possible before condensation drying.
The heating method is not particularly limited. For example, a heating device can be installed above the collection member 13 to heat the collection member 13. The temperature of the recovery member 13 during heating can be set to about 60 ° C., for example.

The distance D between the recovery member 13 and the coating film surface f2a can be set as appropriate, but the distance D is preferably in the range of 0.1 to 10.0 mm from the viewpoint of increasing the recovery efficiency. If the distance D is 0.1 mm or more, it is easy to avoid contact between the coating film f2 and the recovery member 13 due to flapping of the substrate f1, and if it is 10.0 mm or less, silane-based gas precipitates on the surface of the recovery member 13 And diffusion of the silane-based gas can be suppressed.

The solid content ratio of the coating film f2 after the silane-based gas is recovered by the recovery member 13 is preferably 30% by mass or more.
When the solid content ratio is 30% by mass or more, the silane-based gas can be recovered from the coating film f2 to such an extent that a decrease in the drying efficiency of condensation drying can be suppressed.

The solid content ratio is determined as follows.
A sample of the coating film f2 after the silane-based gas is recovered, that is, the sample of the coating film f2 immediately after the substrate f1 exceeds the recovery member 13, is measured and the mass is measured. Next, the sample is put in an aluminum plate and heat-treated at a temperature of 80 ° C. for 3 hours by a heating plate. After the heat treatment, the mass (g) of the sample-containing aluminum plate is measured, and the mass (g) of the residual solvent per unit area remaining in the sample after the heat treatment from the mass difference before and after the heat treatment and the area of the sample. / M ² ) and the solid content ratio is determined by the following formula.
Solid content ratio (% by mass)
= Solid coating amount per unit area (g / m ² ) / {Solid coating amount per unit area (g / m ² ) + Mass of residual solvent per unit area (g / m ² )} × 100

In order to recover the silane-based gas so that the solid content ratio of the coating film f2 is 30% by mass or more, the coating film f2 is heated to a high temperature or the time for the substrate f1 to face the recovery member 13 is increased. Adjust it. For example, by increasing the length of the recovery member 13 in the transport direction y or decreasing the transport speed of the substrate f1, the time for the substrate f1 to face the recovery member 13 becomes longer, and more silane-based gas is recovered. be able to.

The heat roller 14 is a transport roller for the substrate f1 and incorporates a heat source.
As shown in FIG. 1, the heat roller 14 is arranged upstream of the collection member 13 in the transport direction y, and heats the transported substrate f <b> 1 in order to promote generation of silane-based gas.

The surface temperature of the heat roller 14 can be set to about 80 ° C., for example.
The heat roller 14 is installed upstream of the collection member 13 in the transport direction y, but may be installed at a position facing the collection member 13 via the substrate f1.

Similarly, from the viewpoint of promoting the generation of the silane-based gas, the drying apparatus 1 includes an irradiation apparatus that irradiates active energy rays, and the irradiation apparatus applies the coating film f2 just before facing the recovery member 13 or faces it. It is also possible to irradiate active energy rays to the coating film f2. Examples of the active energy rays include visible light, infrared rays, ultraviolet rays, X-rays, α rays, β rays, γ rays, and electron beams.

The drying speed of the drying device 1 can be controlled by adjusting the temperature Tc of the condensing surface 11a and the temperature Th (Th> Tc) of the coating film surface f2a.
The drying speed increases as the difference in the vapor pressure of the solvent at each temperature Tc and Th increases.
As a method for controlling the temperature Tc of the condensing surface 11a, heating or cooling of the condensing plate 11 by blowing or liquid feeding can be mentioned. The temperature Tc of the condensing surface 11a can be set to room temperature without particularly controlling, and the temperature Th of the coating film surface f2a can be controlled to a temperature sufficiently higher than the room temperature.
The temperature Th of the coating film surface f2a can be adjusted by heating with the heating device 12. If necessary, a cooling device can be used together with the heating device 12 to control the temperature Th of the coating film surface f2a.

The temperature Tc of the condensing surface 11a may be higher or lower than room temperature as long as it is lower than the temperature Th of the coating film surface f2a, but is preferably in the range of 5 to 30 ° C, and in the range of 10 to 20 ° C. It is more preferable that
By controlling the temperature Tc within the above range, an increase in cost required for heating can be suppressed. Further, it is easy to uniformly control the temperature of the entire condensing surface 11a, and it is easy to suppress drying unevenness due to temperature unevenness, and consequently film thickness unevenness of the coating film f2. From the same viewpoint, the temperature unevenness in the condensing surface 11a is preferably within 2 ° C.

In order to prevent substances other than the solvent such as moisture in the atmosphere from condensing on the condensation surface 11a, it is preferable to lower the dew point of the atmosphere or reduce the pressure between the condensation surface 11a and the coating film surface f2a.
Further, in order to prevent the solvent from condensing in a member of the drying apparatus 1 other than the condensing plate 11, such as a housing, the temperature of the member other than the condensing plate 11 is preferably adjusted to be equal to or higher than the temperature Tc of the condensing surface 11a. .

The temperature Th of the coating film surface f2a may be higher or lower than the room temperature as long as it is higher than the temperature Tc of the condensing surface 11a, but is preferably in the range of 30 to 100 ° C, preferably in the range of 30 to 70 ° C. It is more preferable that
By setting the temperature Th to 30 ° C. or higher, moisture in the atmosphere other than the solvent is condensed and it is easy to suppress a decrease in drying efficiency. By setting the temperature to 100 ° C. or lower, it is easy to suppress an increase in cost due to a high temperature, conveyance failure due to the modification of the substrate f1, and the like. In addition, it is easy to uniformly control the temperature of the entire substrate f1, and it is easy to suppress drying unevenness due to temperature unevenness, and consequently film thickness unevenness of the coating film f2. From the same viewpoint, the temperature unevenness in the coating film surface f2a is preferably within 2 ° C.

The drying speed of the drying device 1 can also be controlled by adjusting the distance d between the condensation surface 11a and the coating film surface f2a.
The smaller the distance d is, the more easily the solvent is condensed and the drying speed is increased, but it is preferably in the range of 0.1 to 10.0 mm, more preferably in the range of 0.1 to 4.0 mm.
By setting the distance d to 0.1 mm or more, it is easy to avoid contact between the coating film f2 and the condensing plate 11 due to flapping of the substrate f1, and it is possible to reduce the cost associated with high accuracy of the arrangement of the condensing plate 11. Moreover, it is easy to avoid adhesion of the condensed solvent to the coating film f2, and drying unevenness due to adhesion can be suppressed. By setting the distance d within 10.0 mm, it is possible to reduce the influence of surrounding convection and prevent drying unevenness, increase the drying speed, and improve productivity.

The distance d between the condensation surface 11a and the coating film surface f2a is preferably maintained at a constant value.
When the distance d is a constant value, the drying speed in the coating film surface f2a can be made constant, and the uniformity of drying can be improved.

The drying device 4 is a drying device for post-processing provided to remove the residual solvent from the drying device 1.
The drying method of the drying device 4 may be the same condensation drying as the drying device 1, or may be another drying method. Other drying methods include drying using hot air, infrared rays, microwaves, ultrasonic waves, etc., vacuum drying, supercritical drying, moisture absorption drying, cooling drying, and the like.

According to the thin film forming apparatus 100, a coating film containing a silicon compound having a polysilazane skeleton can be formed as a gas barrier layer of a gas barrier film, and the coating film can be uniformly dried.
The gas barrier film is a film having a gas barrier layer exhibiting low oxygen permeability and water vapor permeability, and imparts excellent storage stability to an electronic device using the gas barrier film.
The gas barrier performance required for the gas barrier layer varies depending on the electronic device in which the gas barrier film is used. In general, the gas barrier layer has a water vapor permeability (temperature 60 ± 0.5 ° C., relative humidity 90 ± 2%) measured in accordance with JIS K7129: 2008 of 3 × 10 ⁻³ g / m ² · 24 h or less. Yes, when the oxygen permeability measured according to JIS K7126: 2006 is 1 × 10 ⁻³ g / m ² · 24 h · atm or less, it can be preferably used for an electronic device.

For a silicon compound having a polysilazane skeleton, an organic solvent is used as a solvent, so that the viscosity of the coating film f2 is likely to be a low viscosity of 100 mPa · s or less. When such a low-viscosity coating film f2 is dried by convection heat transfer, the coating liquid flows greatly, the evaporation rate of the solvent is not constant, and drying unevenness is likely to occur.
However, since the drying apparatus 1 does not use convective heat transfer, there is almost no unevenness in the flow of the coating liquid and the evaporation rate of the solvent, and uniform drying is possible even when the coating film f2 has a low viscosity of 100 mPa · s or less. Since it can be realized, it is particularly effective for forming the gas barrier layer described above.

A silicon compound having a polysilazane skeleton is likely to generate a silane-based gas. It has been found that when the coating film f2 is a silicon compound having a polysilazane skeleton, a large amount of silane-based gas is generated immediately after coating.
Although the silane-based gas lowers the condensing action, the drying apparatus 1 performs the condensation drying after collecting the silane-based gas as much as possible by the collecting member 13, so that the silane-based gas generated during the condensation drying can be reduced. Therefore, even when the coating film of the gas barrier layer contains a silicon compound having a polysilazane skeleton, it is possible to achieve uniform drying while suppressing a decrease in drying efficiency, which is particularly effective.

Hereinafter, a procedure for forming a thin film will be described by taking as an example a case where a coating film containing a silicon compound having a polysilazane skeleton is formed and the coating film is dried to form a gas barrier layer.

First, the gas barrier film substrate f <b> 1 is set in the thin film forming apparatus 100.
As the substrate f1 of the gas barrier film, a colorless and transparent resin film is preferably used.
Examples of the resin film material include polyester, methacrylic acid, methacrylic acid-maleic acid copolymer, polystyrene, fluorinated resin, polyimide, fluorinated polyimide, polyamide, polyamideimide, polyetherimide, cellulose acylate, polyurethane, and polyether. Examples include ether ketone, polycarbonate, alicyclic polyolefin, polyarylate, polyether sulfone, polysulfone, cycloolefin copolymer, fluorene ring-modified polycarbonate, alicyclic ring-modified polycarbonate, fluorene ring-modified polyester, and acryloyl compound.

The thickness of the substrate f1 used for the gas barrier film can be appropriately selected depending on the application. In general, the thickness of the substrate f1 is in the range of 1 to 800 μm, preferably in the range of 10 to 200 μm. From the viewpoint of reducing the size and weight of the electronic device, it is more preferably in the range of 10 to 50 μm.

Substrate f1 can be produced by melting and extruding a resin composition as a raw material using an extruder having an annular die or a T die and quenching, and is substantially unstretched with no resin orientation. A substrate f1 is obtained.
This unstretched substrate f1 is stretched by uniaxial stretching, tenter sequential biaxial stretching, tenter simultaneous biaxial stretching or tubular simultaneous biaxial stretching in the transport direction and / or width direction of the substrate f1. A substrate f1 can also be obtained. The width direction refers to a direction orthogonal to the transport direction on the substrate f1. The draw ratio is preferably in the range of 2 to 10 times in the transport direction and the width direction.

The surface of the substrate f1 on which the gas barrier layer is formed may be subjected to surface treatment such as excimer treatment, corona discharge treatment, flame treatment, oxidation treatment, or plasma treatment in order to improve adhesion with the laminated gas barrier layer. Good.

The substrate f1 may be provided with a primer layer in order to flatten the surface of the substrate f1 and improve the adhesion with the gas barrier layer.
The primer layer preferably contains a curable resin such as an active energy ray curable resin or a thermoplastic resin.

As a specific example of the active energy ray curable material, OPSTAR (registered trademark) series which is a UV curable organic / inorganic hybrid hard coat agent manufactured by JSR Corporation can be used. The OPSTAR series is a compound obtained by bonding an organic compound having a polymerizable unsaturated group to silica fine particles.

Specific examples of the thermosetting material include thermosetting urethane resin composed of acrylic polyol and isocyanate prepolymer, phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, silicon resin, polyamidoamine-epichlorohydrin resin, and the like. Can be mentioned. Commercially available thermosetting materials include SP COAT heat-resistant clear paint manufactured by Ceramic Coat, Nanohybrid silicone manufactured by Adeka, Unidic (registered trademark) V-8000 series manufactured by DIC, EPICLON (registered trademark) EXA -4710 (ultra high heat resistant epoxy resin), X-12-2400 (silicon resin) manufactured by Shin-Etsu Chemical Co., Ltd., SSG coat (inorganic or organic nanocomposite material) manufactured by Nitto Boseki Co., Ltd., and the like.

Solvents used in the coating solution containing the curable material include alcohols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, ethylene glycol and propylene glycol, terpenes such as α- or β-terpineol, and acetone. , Ketones such as methyl ethyl ketone, cyclohexanone, N-methyl-2-pyrrolidone, diethyl ketone, 2-heptanone, 4-heptanone, aromatic hydrocarbons such as toluene, xylene, tetramethylbenzene, cellosolve, methyl cellosolve, ethyl cellosolve , Carbitol, methyl carbitol, ethyl carbitol, butyl carbitol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether Ter, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, glycol ethers such as triethylene glycol monoethyl ether, ethyl acetate, butyl acetate, cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, ethyl carbitol Acetates such as acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, 2-methoxyethyl acetate, cyclohexyl acetate, 2-ethoxyethyl acetate, 3-methoxybutyl acetate, diethylene glycol dialkyl ether, Dipropylene glycol dialkyl ether, 3-etho Shipuropion ethyl, methyl benzoate, N, N- dimethylacetamide, N, may be mentioned N- dimethylformamide.

The thickness of the primer layer is not particularly limited, but is preferably in the range of 0.1 to 10.0 μm.

In order to prevent the additive in the substrate f1 from bleeding out (deposition), the substrate f1 may have a bleedout preventing layer formed on the surface opposite to the surface on which the gas barrier layer of the substrate f1 is laminated. .
Since the primer layer described above basically has a function of preventing bleed out, a bleed out preventing layer can be formed in the same manner as the primer layer.

Next, the thin film forming apparatus 100 starts transporting the substrate f1, and the coating apparatus 3 applies the coating liquid for the gas barrier layer onto the substrate f1 to form the coating film f2.

The coating solution for the gas barrier layer can be prepared by dissolving or dispersing a silicon compound having a polysilazane skeleton in a solvent.
The polysilazane skeleton is a basic skeleton of a polymer containing a Si—N bond, and is a precursor of ceramics such as silicon oxide (SiO ₂ ), silicon nitride (Si ₃ N ₄ ), or silicon oxynitride (SiO _x N _y ). is there.
Examples of the silicon compound having a polysilazane skeleton include a silicon compound having a structure represented by the following general formula (1). The silicon compound is generally called polysilazane.

 

In the general formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an aryl group, a vinyl group or a (trialkoxysilyl) alkyl group. The alkyl group, aryl group, vinyl group or (trialkoxysilyl) alkyl group may further have a substituent.

Examples of the alkyl group for R ¹ , R ² and R ³ include straight, branched or cyclic alkyl groups having 1 to 8 carbon atoms. More specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, n -Hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group and the like.

Examples of the aryl group for R ¹ , R ² and R ³ include aryl groups having 6 to 30 carbon atoms. More specifically, a non-condensed hydrocarbon group such as a phenyl group, a biphenyl group, a terphenyl group; a pentarenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptaenyl group, a biphenylenyl group, a fluorenyl group, an acenaphthylenyl group, a preadenyl group A condensed polycyclic hydrocarbon group such as acenaphthenyl group, phenalenyl group, phenanthryl group, anthryl group, fluoranthenyl group, acephenanthrenyl group, aceantrirenyl group, triphenylenyl group, pyrenyl group, chrysenyl group, naphthacenyl group, etc. Can be mentioned.

Examples of the (trialkoxysilyl) alkyl group of R ¹ , R ² and R ³ include an alkyl group having 1 to 8 carbon atoms having a silyl group substituted with an alkoxy group having 1 to 8 carbon atoms. More specific examples include 3- (triethoxysilyl) propyl group and 3- (trimethoxysilyl) propyl group.

In some cases, examples of the substituent present in the alkyl group, aryl group, vinyl group or (trialkoxysilyl) alkyl group include an alkyl group, a halogen atom, a hydroxy group (—OH), a mercapto group (—SH), a cyano group. Groups (—CN), sulfo groups (—SO ₃ H), carboxy groups (—COOH), nitro groups (—NO ₂ ) and the like.
The substituent which the alkyl group, aryl group, vinyl group or (trialkoxysilyl) alkyl group may have is the same as the substituted alkyl group, aryl group, vinyl group or (trialkoxysilyl) alkyl group. Absent. For example, when R ¹ to R ³ are alkyl groups, they are not further substituted with an alkyl group.

Preferred R ¹ , R ² and R ³ are hydrogen atom, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, phenyl group, vinyl group, 3- (triethoxysilyl) A propyl group or a 3- (trimethoxysilylpropyl) group.

In the general formula (1), n is an integer of 1 or more.
n is preferably determined so that the number average molecular weight Mn of the silicon compound having the structure represented by the general formula (1) is in the range of 150 to 150,000 g / mol.

Among the silicon compounds having the structure represented by the general formula (1), perhydropolysilazane in which all of R ¹ , R ² and R ³ are hydrogen atoms, the resulting gas barrier layer exhibits high density, Particularly preferred.
Perhydropolysilazane is presumed to have a structure including a linear structure and a ring structure centered on a 6-membered ring and an 8-membered ring. Perhydropolysilazane has a number average molecular weight Mn measured in terms of polystyrene by gel permeation chromatography of about 600 to 2000, and is a liquid or solid substance.

Perhydropolysilazane is commercially available as a solution dissolved in an organic solvent, and the commercially available product can be used as it is as a coating solution for the gas barrier layer.
Commercially available products that can be used as the coating solution include AQUAMICA (registered trademark) series NN120-10, NN120-20, NAX120-20, NN110, NN310, NN320, NL110A, NL120A, NL120-20 manufactured by AZ Electronic Materials. NL150A, NP110, NP140, SP140 and the like.

Organopolysilazane, in which at least one of R ¹ , R ² and R ³ is a hydrogen atom and at least one is an organic group such as an alkyl group, also has good adhesion to the substrate f1 and is a ceramicized gas barrier layer Even when the toughness is imparted to the gas barrier layer to increase the thickness of the gas barrier layer, the generation of cracks can be suppressed, which is preferable.
Perhydropolysilazane or organopolysilazane may be selected depending on the application, and both may be used in combination.

As another example of the silicon compound that can be used for the gas barrier layer, a silicon alkoxide-added polysilazane obtained by reacting a silicon alkoxide with a silicon compound having a structure represented by the above general formula (1) (Japanese Patent Laid-Open No. 5-238827) Glycidol-added polysilazane obtained by reacting glycidol (see JP-A-6-122852), alcohol-added polysilazane obtained by reacting alcohol (see JP-A-6-240208), metal carboxylate A metal carboxylate-added polysilazane obtained by reacting with a metal (see JP-A-6-299118), and an acetylacetonate complex-added polysilazane obtained by reacting a metal-containing acetylacetonate complex (JP-A-6-306329) Add metal fine particles) Resulting Te metal particles added polysilazane (see JP-A-7-196986) and the like. These are examples of silicon compounds that ceramize at low temperatures.

Since the silicon compound having a polysilazane skeleton reacts with a reactive group such as a hydroxy group or an amino group and is easily hydrolyzed, the solvent used for the coating solution is an organic solvent inert to the silicon compound. Is preferred.
Specifically, aprotic solvents such as aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons and halogen hydrocarbons; esters such as ethyl acetate and butyl acetate; ketones such as acetone and methyl ethyl ketone; Mention may be made of ethers such as butyl ether, dioxane, tetrahydrofuran, mono- or polyalkylene glycol dialkyl ethers (diglymes).
A solvent can be selected according to the solubility of a silicon compound, the evaporation rate of a solvent, etc., and may use 1 type (s) or 2 or more types.

The silicon compound content in the coating solution varies depending on the film thickness of the gas barrier layer and the pot life of the coating solution, but is preferably in the range of 0.2 to 80.0% by weight, more preferably 1 to 50% by weight. %, Particularly preferably in the range of 5 to 35% by weight.

The coating solution may contain a catalyst in order to promote silica conversion during the modification treatment.
Usable catalysts include N, N-diethylethanolamine, N, N-dimethylethanolamine, triethanolamine, triethylamine, 3-morpholinopropylamine, N, N, N ′, N′-tetramethyl-1,3 -Amine catalysts such as diaminopropane, N, N, N ', N'-tetramethyl-1,6-diaminohexane, Pt compounds such as Pt acetylacetonate, Pd compounds such as propionic acid Pd, Rh acetylacetonate, etc. And metal catalysts and N-heterocyclic compounds. Of these, a basic catalyst is preferable, and an amine catalyst is preferable.
The content of the catalyst in the coating solution is preferably in the range of 0.1 to 10.0 mol%, more preferably in the range of 0.5 to 7.0 mol% with respect to the content of the silicon compound. Is within. By setting the content of the catalyst within the above range, it is possible to avoid excessive silanol formation, film density reduction, film defect increase, and the like due to rapid progress of the reaction.

The film thickness at the time of application | coating of the coating film f2 can be determined according to the film thickness calculated | required after drying.
The greater the film thickness at the time of coating, the more easily the coating liquid flows and uneven drying occurs. Therefore, the usefulness of the drying apparatus 1 capable of uniform drying is great.

The viscosity of the coating film f2 can be appropriately selected depending on the gas barrier performance required for the gas barrier layer and the solubility or decomposability of the silicon compound.
For a silicon compound having a polysilazane skeleton, an organic solvent is used as described above, so that the viscosity of the coating solution is as low as 100 mPa · s or less. In the coating film f2, since the coating liquid easily flows and uneven drying tends to occur, the usefulness of the drying apparatus 1 capable of uniform drying is great.
The specific viscosity of the coating film is preferably in the range of 0.3 to 10.0 mPa · s from the viewpoint of increasing the coating speed and improving the coating property, and 1.0 to 10.0 mPa · s. More preferably within the range of s.

Next, the drying apparatus 1 collects the silane-based gas generated from the coating film f2 of the gas barrier layer.
The drying apparatus 1 heats the coating film f <b> 2 through the substrate f <b> 1 by the heat roller 14, and collects the silane-based gas generated from the coating film f <b> 2 by the collection member 13.

When the silane-based gas is recovered, the drying device 1 condenses and dries the coating film f2 of the gas barrier layer.
The drying device 1 heats the substrate f1 by the heating device 12. When the solvent in the coating film f2 is evaporated by heating the substrate f1, the vapor is condensed by the condensing plate 11 facing the coating film f2, and the coating film f2 is dried.

The thickness of the gas barrier layer after drying is preferably in the range of 1 nm to 100 μm, more preferably in the range of about 10 nm to 10 μm, still more preferably in the range of 50 nm to 1 μm, particularly preferably. It is in the range of 100 to 500 nm.
If the film thickness is 1 nm or more, sufficient gas barrier performance can be obtained, and if it is 100 μm or less, stable coating properties and high light transmittance are obtained.

After the coating film f2 is dried, the reforming apparatus 5 modifies the coating film f2 on the substrate f1, thereby obtaining a gas barrier layer.
The modification treatment is a treatment in which part or all of the silicon compound contained in the coating film f2 of the gas barrier layer is converted into silica and converted into ceramics.
Examples of the modification treatment include a method of irradiating ultraviolet light having a wavelength of 400 nm or less, a method of irradiating vacuum ultraviolet light (VUV; Vacuum Ultra Violet) having a wavelength of less than 180 nm, and the like.

The example of forming the gas barrier layer of the gas barrier film has been described above, but other layers such as a primer layer and a bleed-out layer can also be formed by the thin film forming apparatus 100.
In addition to the gas barrier film, the coating device 3 is used to form a coating film f2 of an organic layer such as an organic EL element, a solar cell, a transistor, a memory, a sensor, etc., and the coating device f2 is dried by the drying device 1 A thin film can be formed.
Also in the formation of the organic layer, when an organic solvent is used for the coating solution and the coating film f2 has a low viscosity, the film thickness is uniform so that the functions required for the organic layer can be obtained by uniform drying by the drying device 1. This is effective.

As described above, the drying apparatus 1 according to the present embodiment includes the condensing plate 11 that faces the coating film f2 on the substrate f1, and condenses the solvent vapor from the coating film f2 by the condensing plate 11 to dry. The coating film f2 contains a silicon compound that generates a silane-based gas, and serves as a recovery unit that recovers the silane-based gas generated from the coating film f2 before drying the condensing plate 11. A flat recovery member 13 is provided so as to face the upper coating film f2.

Since the silane-based gas is collected in advance, the silane-based gas generated from the coating film f2 during the condensation drying and hindering the condensation of the solvent can be reduced. A decrease in the condensing action of the condensing plate 11 due to the silane-based gas can be suppressed, and a decrease in the drying efficiency of the condensation drying can be suppressed. Due to the reduction of the silane-based gas, the amount of deposits adhering to the condensing surface 11a is also reduced, so that the failure of deposits adhering to the coating film f2 can be reduced.

[Other Embodiments]
As another recovery means for the silane-based gas, the drying device 1 may include a blowing device and / or a suction device for forming an air flow for discharging the silane-based gas in addition to the recovery member 13.
FIG. 4 shows an example in which the blower 15 and the suction device 16 are arranged before and after the collection member 13 in the transport direction y.
The blower 15 sends out air between the collection member 13 and the coating film f2, and discharges the silane-based gas generated from the coating film f2.
The suction device 16 sucks air containing a silane-based gas and discharges the silane-based gas generated from the coating film f2.
The recovery member 13 collects and recovers silane-based gas on the surface. The recovery member 13 is also an air guide plate.

The air flow for discharging the silane-based gas is preferably formed so as to go from the downstream side to the upstream side in the transport direction y, as indicated by the white arrow in FIG. As the substrate f1 is transported, an airflow is formed from upstream to downstream in the transport direction y. By forming an airflow in a direction opposite to the airflow, convection is generated, and the generation of silane-based gas is promoted by the convection. be able to. It is also possible to prevent the silane-based gas from flowing into the condenser plate 11.

Only one of the blower 15 and the suction device 16 can form an air flow for discharging the silane-based gas. The drying device 1 includes only one of the blower 15 and the suction device 16 and sends out air by the blower 15 or sucks air by the suction device 16 to discharge the silane-based gas from the coating film f2. May be.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.
In the following examples, “part” or “%” is used, and “part by weight” or “% by weight” is represented unless otherwise specified.

[Production of drying apparatus K1]
Slits with a width of 2 mm and a depth of 2 mm are formed at intervals of 2 mm in the width direction on one surface of an aluminum plate having a length in the width direction of 400 mm, a length in the transport direction of 1000 mm, and a thickness of 20 mm. Then, a condenser plate was produced.
In addition, an infrared heater SG4040 (manufactured by YAC Denco) having a length in the width direction of 400 mm and a length in the transport direction of 400 mm was prepared as a heating device. Three infrared heaters SG4040 were connected to each other so as to face the substrate at a position facing the produced condensing plate through the substrate.

A quartz glass plate having a length in the width direction of 400 mm, a length in the transport direction of 300 mm, and a thickness of 20 mm was disposed upstream of the condensing plate in the transport direction of the substrate as a silane-based gas recovery member.
Further, an infrared heater was installed on the quartz glass plate to produce a drying device K1 having the same configuration as the drying device 1 of FIG. The distance between the infrared heater and the quartz glass plate was adjusted so that the temperature of the quartz glass plate was 60 ° C.

[Production of drying apparatus K21]
In the production of the drying device K1, the drying device K21 is produced in the same manner as the drying device K1, except that the quartz glass plate and the infrared heater on the quartz glass plate are not provided, and only the condensing plate and the heating device are configured. did.

[Preparation of gas barrier film 1]
(Production of substrate)
As the substrate, a polyester film (manufactured by Teijin DuPont Films Co., Ltd., extremely low heat yield PET) whose both surfaces were easily bonded was used. The polyester film had a width in the width direction of 0.35 m, a length in the conveyance direction of 50 m, and a thickness of 125 μm.
On one surface of the substrate, a UV curable organic / inorganic hybrid hard coat agent OPSTAR Z7535 (manufactured by JSR) was applied by a slot method so that the film thickness after drying was 4 μm. After coating, the coating was dried at 80 ° C. for 3 minutes, and cured by irradiation with light of 1.0 J / cm ² using a high-pressure mercury lamp in an air atmosphere to form a bleed-out prevention layer.

Next, UV curable organic / inorganic hybrid hard coat agent OPSTAR Z7501 (manufactured by JSR) is applied to the surface of the substrate opposite to the surface provided with the bleed-out prevention layer so that the film thickness after drying becomes 4 μm. Was applied by the slot method. After application, the coating was dried at 80 ° C. for 3 minutes, and cured by irradiation with 1.0 J / cm ² of light using a high-pressure mercury lamp in an air atmosphere to form a primer layer.

(Production of gas barrier layer)
The produced drying apparatus K1 and coating apparatus were arranged in the same manner as the thin film forming apparatus 100 shown in FIG. As a coating apparatus, a slit type die coater having a width of 0.3 m and a slit interval of 100 μm was used.
On the primer layer of the substrate, a coating film of a gas barrier layer was formed by a coating apparatus, and after the silane-based gas was collected by a drying apparatus K1, the coating film was dried.

The coating solution for the gas barrier layer was prepared as follows.
4 g of Aquamica NN120-20 (20% by weight dibutyl ether solution of perhydropolysilazane, AZ Electronic Materials) and 1 g of Aquamica NAX120-20 (19% by weight of perhydropolysilazane containing 1% by weight amine catalyst) Dibutyl ether solution, manufactured by AZ Electronic Materials) was mixed. 4.636 g was taken from this mixture, 0.613 g of ALCH (aluminum ethyl acetoacetate diisopropylate, manufactured by Kawaken Fine Chemical Co., Ltd.) and 10.151 g of dibutyl ether were added, mixed and applied. A liquid was obtained.

The coating conditions of the coating device are as follows.
(Application conditions)
Substrate transport speed: 10 m / min
Environmental temperature during application: 25 ° C
Applied length in the width direction: 0.3 m
Applied length in transport direction: 50m
The conveyance speed of the substrate was measured with a laser Doppler velocimeter LV203 (manufactured by Mitsubishi Electric Corporation).

The viscosity of the coated film was measured with a digital viscometer HV-50 (manufactured by Brookfield) and found to be 0.5 mPa · s.
Moreover, it was 4 micrometers when the film thickness of the coating film was computed by the following formula.
Coating film thickness = coating amount (g / m ² ) / specific gravity of coating solution (g / m ³ )
Application amount (g / m ² ) = application liquid supply speed (g / sec) / {length in the width direction applied (m) × application speed (m / sec)}

The conditions for collecting the silane-based gas in the drying device K1 are as follows.
(Recovery conditions)
Temperature of recovery member: 60 ° C
Substrate transport speed: 10 m / min

The drying conditions of the drying device K1 are as follows.
(Drying conditions)
Condensing surface temperature Tc: 20 ° C.
Temperature Th of coating film surface: 40 ° C
Distance d between condensation surface and coating film surface: 2 mm
Substrate transport speed: 10 m / min

The distance d between the condensation surface and the coating film surface was adjusted by adjusting the positional relationship between the condensation plate and the substrate transport roller.
The temperature Th of the coating film surface was measured by a radiation temperature sensor FT-30 (manufactured by Keyence Corporation), and was adjusted to the above temperature by changing the distance between the substrate and the infrared heater SG4040.

When the solid content ratio of the coating film was measured at the exit of the silane-based gas recovery step, that is, immediately after the installation position of the quartz glass plate in the substrate transport direction, it was 30% by mass.
The solid content ratio of the coating film was measured as follows.
A sample was taken from the coating film at the exit of the silane-based gas recovery step, and the mass was measured. The collected sample was placed in an aluminum plate and heat-treated with a heating plate at a temperature of 80 ° C. for 3 hours. After the heat treatment, the mass (g) of the sample-containing aluminum plate is measured, and the mass (g) of the residual solvent per unit area remaining in the sample after the heat treatment from the mass difference before and after the heat treatment and the area of the sample. / M ² ) and the solid content ratio is determined by the following formula.
Solid content ratio (% by mass)
= Solid coating amount per unit area (g / m ² ) / {Solid coating amount per unit area (g / m ² ) + Mass of residual solvent per unit area (g / m ² )} × 100

After drying, the coating film obtained was irradiated with vacuum ultraviolet light to convert the perhydropolysilazane in the gas barrier layer into silica to obtain a gas barrier layer.
The vacuum ultraviolet light was irradiated using a stage movable xenon (Xe) excimer irradiation apparatus MECLM-1-200 (irradiation wavelength: 172 nm, excimer lamp light intensity: 312 mW / cm ² ) manufactured by MD Excimer. At the time of irradiation, the substrate was transported so that the distance between the light source and the substrate was 1 mm, and the substrate temperature (stage heating temperature) was maintained at 100 ° C. The conveyance speed of the substrate was 1.5 m / min. In addition, the flow rate of nitrogen gas and oxygen gas introduced into the vacuum ultraviolet irradiation chamber is measured with a flow meter, and the nitrogen concentration is adjusted so that the oxygen concentration during irradiation is in the range of 0.2 to 0.4% by volume. The flow rate ratio (nitrogen gas / oxygen gas) of gas and oxygen gas was adjusted.

[Production of gas barrier films 2 to 4]
In the production of the gas barrier film 1, except that the substrate conveyance speed was adjusted so that the solid content ratio of the coating film measured at the exit of the silane-based gas recovery step was the solid content ratio shown in Table 1 below. In the same manner as the gas barrier film 1, gas barrier films 2 to 4 were produced.
In the production of each gas barrier film 2 to 4, when the solid content ratio of the coating film was measured in the same manner as the gas barrier film 1, it was 40, 29, and 20% by mass, respectively.

[Preparation of gas barrier film 5]
In the production of the gas barrier film 1, a gas barrier film 5 was produced in the same manner as the gas barrier film 1 except that the drying device K1 was changed to the drying device K21.
In production of the gas barrier film 5, the solid content ratio of the coating film was measured in the same manner as in the gas barrier film 1, and it was 5% by mass.

[Evaluation]
The produced gas barrier films 1 to 5 were evaluated as follows.

(1) Drying efficiency When the coating film of the gas barrier layer was condensed and dried, the drying speed was calculated at regular intervals within the range of 0 to 10 m and 190 to 200 m in the length of the substrate transport direction. . The drying rate was calculated by the following formula using the measured values obtained by measuring the film thickness of the coating film immediately before and after condensing and drying, that is, immediately before facing the condensing plate, and immediately after exceeding the condensing plate. . For measuring the film thickness, a film thickness measuring device F-20 (manufactured by Filmetrics) was used.
Drying speed =
{(Film thickness before condensation drying) − (film thickness after condensation drying)} / (substrate transport time during condensation drying)

The average value of each drying speed calculated within the range of 0 to 10 m was determined as the initial drying speed 1. Further, the average value of the respective drying speeds calculated within the range of 190 to 200 m was determined as the drying speed 2 at the 200 m substrate position.

From the obtained drying speed 1 and drying speed 2, the drying efficiency was evaluated as follows.
5: Drying speed 2 / Drying speed 1 is 0.99 or more and there is no reduction in drying efficiency 4: Drying speed 2 / Drying speed 1 is in the range of 0.95 or more and less than 0.99, and the drying efficiency is There is almost no reduction 3: Drying speed 2 / Drying speed 1 is in the range of 0.90 or more and less than 0.95, and a decrease in drying efficiency is observed, but there is no practical problem 2: Drying speed 2 / Drying speed 1 Is in the range of 0.80 or more and less than 0.90, the drying efficiency is low, and practical use is difficult 1: Drying speed 2 / Drying speed 1 is less than 0.80, and the reduction of the drying efficiency is remarkable. Not practical

(2) Number of Failures Measured on the surface of the gas barrier layer of each of the gas barrier films 1 to 5 was a defective portion where foreign matter was adhered using an image measurement system NEXIV VMR-6555 (Nikon Corporation). Measurements were performed at 900 points at different intervals in the transport direction at intervals of 0.01 m in the width direction. The rank evaluation was performed as follows, with the number of measured defective portions as the number of failure occurrences.
5: Number of failures occurring less than 1 4: Number of failures occurring from 1 to less than 3 3: Number of failures occurring from 3 to less than 5 2: Number of failures occurring from 5 to less than 7 1: Number of failures occurring 7 or more

(3) Stability of gas barrier layer The infrared spectrum of each of the gas barrier films 1 to 5 was measured using Nicolet 380 (manufactured by Thermo Fisher Scientific) at room temperature (temperature 25 ° C., relative humidity 65%).
After the measurement, each of the gas barrier films 1 to 5 was stored continuously in a constant temperature and humidity oven Yamato Humidic Chamber IG47M (manufactured by Yamato Scientific Co., Ltd.) adjusted to a high temperature and high humidity of 85 ° C. and 85% relative humidity for 120 hours. . Thereafter, the infrared spectrum of each of the gas barrier films 1 to 5 returned to room temperature was measured again.
In the absorption band of 800 to 850 cm ⁻¹ of each infrared spectrum measured before and after storage under high temperature and high humidity, the peak intensity of the peak derived from Si—N is obtained, and the peak intensity is stored under high temperature and high humidity. The rate of change before and after was calculated by the following formula.
Change rate of peak intensity = peak intensity after storage / peak intensity before storage

The rate of change of the obtained peak intensity before and after storage was evaluated for rank as follows as the stability of the gas barrier layer.
5: Change rate of peak intensity is less than 0.5 and shows very excellent stability 4: Change rate of peak intensity is 0.5 or more and less than 0.7 and shows excellent stability 3: The change rate of peak intensity is 0.7 or more and less than 0.8, and shows practically usable stability 2: The change rate of peak intensity is 0.8 or more and less than 0.9, and the stability is low 1 : The rate of change in peak intensity is 0.9 or more, and the stability is very low

(4) Gas barrier properties The water vapor permeability (g / m ² · 24 h) of each of the gas barrier films 1 to 5 was determined by the calcium corrosion method described in JP-A-2005-283561.
First, the gas barrier films 1 to 5 were cut out, and using a vacuum evaporation apparatus JEE-400 (manufactured by JEOL Ltd.), calcium was vapor-deposited on a part of the cut out sample, and nine 12 mm × 12 mm calcium layers were formed. Provided. At the time of vapor deposition, the portions other than each calcium layer were masked.

The mask was removed in a vacuum state, and aluminum was deposited from another deposition source to cover the entire surface including the calcium layer, thereby forming a sealing layer. Next, the vacuum state is released, and it is quickly transferred to a dry nitrogen gas atmosphere, and an ultraviolet curable resin T470 / UR7134 (manufactured by Nagase ChemteX) is applied on the film surface on which the sealing layer is formed. Quartz glass having a thickness of 0.2 mm was disposed. An evaluation cell was produced by irradiating ultraviolet light through quartz glass to cure the ultraviolet curable resin.

The obtained cells for evaluation of the respective gas barrier films 1 to 5 were stored in a constant temperature and humidity oven Yamato Humidic Chamber IG47M adjusted to a temperature of 85 ° C. and a relative humidity of 85% for 120 hours continuously.
From each image obtained by photographing the evaluation cell when the storage time T (h) is T = 0 and T = 120, a corrosion area of calcium was extracted by image processing. From the area of the extracted corrosion area, the amount of water vapor required for corrosion was calculated as the amount of water vapor permeation by the following formula.
Water vapor transmission rate (g / m ² · 24 h) = X × 18 × 2 × (10 ⁴ / A) × (24 / T)

In the above formula, X represents the molar amount of calcium hydroxide produced by the reaction of calcium with water, and is represented by X = (δ × d ₀ × α × d ₂ ) / M ₂ .
A represents the area (cm ² ) of the calcium layer.
δ represents the area (cm ² ) of the corrosion area of calcium. d ₀ represents the thickness (cm) of the calcium layer. α is a correction factor for the thickness of the calcium layer, and is determined within a range of 1 <α ≦ (M ₂ / d ₂ ) / (M ₁ / d ₁ ). d ₁ represents the density of calcium (g / cm ³ ), and d ₂ represents the density of calcium hydroxide (g / cm ³ ). M ₁ represents the molecular weight of calcium, and M ₂ represents the molecular weight of calcium hydroxide.

From the respective water vapor transmission amounts obtained when T = 0 and T = 120, the rate of change of the water vapor transmission amount before and after storage under high temperature and high humidity was determined as the water vapor transmission rate by the following formula.
Water vapor permeability ^(g / m 2 · 24h)
= (Water vapor transmission amount when T = 0) / (Water vapor transmission amount when T = 120)

The obtained water vapor permeability was ranked as follows as gas barrier properties under high temperature and high humidity.
5: Water vapor permeability is less than 0.1 and shows very good gas barrier properties 4: Water vapor permeability is 0.1 or more and less than 0.3 and shows excellent gas barrier properties 3: Water vapor permeability is It is 0.3 or more and less than 0.6, and shows a practical gas barrier property. 2: Water vapor permeability is 0.6 or more and less than 0.8, and gas barrier property is low 1: Water vapor permeability is 0.8 or more. Yes, gas barrier property is very low

Table 1 below shows the evaluation results.

As shown in Table 1, according to the gas barrier films 1 to 4 according to the examples, compared with the gas barrier film 5 according to the comparative example, all of them have a smaller number of failures, and a decrease in drying efficiency is suppressed. Yes. Moreover, the gas barrier layer excellent in stability and gas barrier property is obtained by uniform drying. Since the silane-based gas was collected before the condensation drying, it is assumed that the number of failures due to silane-based gas deposits has decreased. In addition, the condensation of the solvent was not hindered, and the decrease in the condensing action of the condensing plate was also suppressed, so it is assumed that the decrease in the drying efficiency was suppressed.

When the gas barrier film 5 was produced, the substrate was transported 200 m, and when the condensation surface was confirmed, deposits were adhered. Since the drying device K21 used for the condensation drying was not provided with a silane-based gas recovery member, the silane-based gas prevented the solvent from condensing, and deposits adhered to the condensation surface, significantly reducing the condensation action. It is speculated that the drying efficiency was lowered. Moreover, it is guessed that the deposit on the condensation surface adhered to the coating film and the number of failures increased.

The present invention can be used in a drying apparatus and a drying method for condensing solvent vapor from a coating film containing a silicon compound that generates a silane-based gas.

DESCRIPTION OF SYMBOLS 100 Thin film forming apparatus f1 Substrate f2 Coating film f2a Coating film surface 1 Drying device 11 Condensing plate 11a Condensing surface 12 Heating device 13 Recovery member 14 Heat roller 3 Coating device

Claims (6)

1. A drying apparatus comprising a condensing plate facing a coating film on a substrate, condensing the solvent vapor from the coating film with the condensing plate, and drying,
   The coating film contains a silicon compound that generates a silane-based gas,
   A drying apparatus comprising a recovery means for recovering a silane-based gas generated from the coating film before drying by the condenser plate.
2. 2. The drying apparatus according to claim 1, wherein the recovery means is a planar recovery member disposed so as to face the coating film on the substrate.
3. The drying apparatus according to claim 2, wherein the recovery member is heated.
4. The drying apparatus according to any one of claims 1 to 3, wherein a solid content ratio of the coating film after the silane-based gas is recovered by the recovery means is 30% by mass or more.
5. The drying apparatus according to any one of claims 1 to 4, wherein the silicon compound is a silicon compound having a polysilazane skeleton.
6. A condensing plate facing the coating film on the substrate is a drying method for condensing and drying the solvent vapor from the coating film,
   A drying method characterized in that, when a coating film containing a silicon compound that generates a silane-based gas is dried, the silane-based gas generated from the coating film is recovered by a recovery means before drying by the condenser plate.

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