JP2020073629A - Void layer, laminate, production method for void layer, optical member, and optical device - Google Patents

Abstract

To provide a void layer in which an adhesive or an adhesive layer is difficult to impregnate in a void.SOLUTION: In order to achieve the object, a void layer of the present invention contains nano-particles surface-modified with a compound having a surface orientation, and having a void ratio of 35 vol% or higher.SELECTED DRAWING: None

Description

  The present invention relates to a void layer, a laminated body, a method for producing a void layer, an optical member and an optical device.

In the optical device, for example, an air layer having a low refractive index is used as the total reflection layer. Specifically, for example, each optical film member (for example, a light guide plate and a reflection plate) in a liquid crystal device is laminated with an air layer in between. However, if the members are separated by an air layer, problems such as bending of the members may occur especially when the members are large. Further, due to the trend of thinning devices, it is desired to integrate each member. For this reason, each member has been integrated with an adhesive without interposing an air layer (for example, Patent Document 1). However, if the air layer that plays the role of total reflection disappears, the optical characteristics such as light leakage may deteriorate.

Therefore, it has been proposed to use a low refractive index layer instead of the air layer. For example, Patent Document 2 describes a structure in which a layer having a lower refractive index than the light guide plate is inserted between the light guide plate and the reflection plate. As the low-refractive index layer, for example, a void layer having voids is used in order to make the refractive index as low as possible to that of air.

JP2012-156082A JP-A-10-62626

The void layer is used, for example, by laminating it with another layer via an adhesive layer. However, when the void layer and the tacky adhesive layer are laminated, inside the voids of the void layer, the pressure-sensitive adhesive or adhesive constituting the adhesive layer penetrates to fill the voids, resulting in a void ratio of It may decrease. Then, the higher the porosity of the void layer, the more easily the pressure-sensitive adhesive or the adhesive penetrates. Further, under a high temperature environment, the pressure-sensitive adhesive or the adhesive easily penetrates into the voids due to the molecular movement of the pressure-sensitive adhesive or the adhesive.

In order to suppress or prevent the permeation of the pressure-sensitive adhesive or the adhesive into the voids, a material having a high elastic modulus (hard) may be used as the pressure-sensitive adhesive or the adhesive. However, if the elastic modulus of the pressure-sensitive adhesive or the adhesive is high (hard), the pressure-sensitive adhesive force or the adhesive force may decrease. Conversely, if the elastic modulus of the pressure-sensitive adhesive or the adhesive is low (soft), high pressure-sensitive adhesive force or adhesive force is easily obtained, but the pressure-sensitive adhesive or adhesive may easily penetrate into the voids.

In order to suppress or prevent the penetration of the pressure-sensitive adhesive or adhesive into the voids, for example,
It is also conceivable to form a layer (permeation suppression layer) capable of suppressing permeation of the pressure-sensitive adhesive or the adhesive on the void layer using a substance other than the pressure-sensitive adhesive or the adhesive. However, in that case, the step of forming the permeation suppression layer is required in addition to the step of forming the void layer, which leads to an increase in the number of manufacturing steps.

For these reasons, a void layer in which a pressure-sensitive adhesive or an adhesive does not easily penetrate is required.

Therefore, an object of the present invention is to provide a void layer, a laminate, a method for producing the void layer, an optical member, and an optical device in which a pressure-sensitive adhesive or an adhesive hardly penetrates into the void.

In order to achieve the above object, the void layer of the present invention is characterized by containing nanoparticles surface-modified with a compound having surface orientation and having a porosity of 35% by volume or more.

The laminate of the present invention is a laminate in which the void layer of the present invention and an adhesive layer are directly laminated.

The method for producing a void layer of the present invention comprises a coating step of applying a dispersion liquid containing the nanoparticles, and a drying step of drying the coated dispersion liquid, the production of the void layer of the present invention Is the way.

  The optical member of the present invention is an optical member including the laminate of the present invention.

  The optical device of the present invention is an optical device including the optical member of the present invention.

According to the present invention, it is possible to provide a void layer, a laminate, a method for producing a void layer, an optical member and an optical device in which a pressure-sensitive adhesive or an adhesive hardly penetrates into voids.

FIG. 1 is a process cross-sectional view schematically showing an example of a method for forming a laminate of the present invention in which a void layer 21, an intermediate layer 22 and an adhesive layer 30 are laminated on a resin film 10 in the present invention. Is. FIG. 2 is a diagram schematically showing a part of steps in a method for manufacturing a roll-shaped laminated film (laminated film roll) and an example of an apparatus used for the same. FIG. 3 is a diagram schematically showing a part of the steps in the method for manufacturing a laminated film roll and another example of the apparatus used for the steps. FIG. 4 is a cross-sectional photograph of the laminated body manufactured in Example 1. FIG. 5 is a cross-sectional photograph of the laminated body manufactured in Comparative Example 1. FIG. 6 is a cross-sectional photograph of the laminated body manufactured in Comparative Example 2.

Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following description.

In the void layer of the present invention, for example, the compound having surface orientation is an alkoxysilane derivative, and the alkoxysilane derivative has 5 to 17 or 5 fluorine atoms.
It may contain 10 fluoroalkyl groups. The fluoroalkyl group may be an alkyl group in which only part of hydrogen is replaced with fluorine, or may be an alkyl group in which all hydrogen is replaced with fluorine (perfluoroalkyl group).

In the void layer of the present invention, for example, the nanoparticles are added to the skeleton component of the void layer in an amount of 10 to 5
You may contain 0 mass%.

In the method for producing a void layer of the present invention, for example, a layer made of the nanoparticles may be formed inside the void layer together with the formation of the void layer.

In the void layer of the present invention, the pressure-sensitive adhesive or the adhesive hardly penetrates into the voids. Therefore, it is not necessary to form another permeation suppression layer, and the void layer of the present invention and the adhesive layer can be directly laminated. Therefore, it is possible to avoid an increase in the number of manufacturing steps due to the step of forming the permeation suppression layer.

The reason (mechanism) that the pressure-sensitive adhesive or the adhesive hardly penetrates into the voids in the void layer of the present invention is considered as follows, for example. First, by utilizing the surface orientation (movement to the air interface) of a compound having a surface orientation (for example, a compound having a perfluoroalkyl), a surface orientation is imparted to the nanoparticles themselves surface-modified with the compound. To do. Here, the surface of the void layer can be modified only by the compound having the surface orientation, but it is not sufficient to suppress the permeation of the macro adhesive. Therefore, the nanoparticles fill the voids on the outermost surface of the void layer to physically suppress the penetration of the pressure-sensitive adhesive or the adhesive. However, nanoparticles without surface modification are
Since it has no surface orientation, it does not orient itself on the surface of the void layer even if it exists in the void layer, and the permeation suppression effect does not appear. By modifying the nanoparticles with a compound having a surface orientation, the nanoparticles have a surface orientation to the void layer. Thereby, as described above, the nanoparticles fill the voids on the outermost surface of the void layer and physically suppress the permeation of the pressure-sensitive adhesive or the adhesive. That is, nanoparticles modified with a compound having surface orientation fill the voids on the outermost surface of the void layer, thereby forming a pressure-sensitive adhesive or a permeation suppression layer for the adhesive on the outermost surface (surface layer). As a result, as described above, the step of forming another permeation suppression layer is unnecessary, and an increase in the number of manufacturing steps due to the step of forming the permeation suppression layer can be avoided. However, these mechanisms are merely examples and do not limit the present invention. In order to produce the void layer of the present invention, for example, nanoparticles modified with a compound having surface orientation may be added to the coating liquid for forming the void layer, as will be described later.

[1. Void layer, laminated body, optical member and optical device]
As described above, the void layer of the present invention contains nanoparticles surface-modified with a compound having surface orientation, and has a porosity of 35% by volume or more. Further, in the laminate of the present invention, as described above, the void layer of the present invention and the adhesive layer are directly laminated. The adhesive layer may be laminated on one side or both sides of the void layer of the present invention. In the present invention, the “adhesive layer is“ directly laminated ”to the void layer” means that the adhesive layer may be in direct contact with the void layer, or the adhesive layer is The adhesive layer may be laminated on the void layer via a layer (penetration suppression layer) formed of nanoparticles (nanoparticles surface-modified with a compound having surface orientation) in the void layer, or the adhesive layer. However, it may be laminated on the void layer via an intermediate layer formed by uniting the void layer and the adhesive layer.

In the present invention, the light transmittance of the void layer of the present invention or the laminate of the present invention is 80.
% Or more. Further, for example, the haze of the void layer of the present invention or the laminate of the present invention may be 3% or less. The light transmittance is, for example, 82% or more, 84% or more,
It may be 86% or more, or 88% or more, and the upper limit is not particularly limited, but ideally 100%, for example, 95% or less, 92% or less, 91% or less, or 90% or less. It may be. The haze of the void layer of the present invention or the laminate of the present invention can be measured by, for example, a haze measuring method described later. In addition, the light transmittance is 55
It is the transmittance of 0 nm light, and can be measured, for example, by the following measuring method.

(Measurement method of light transmittance)
Using the spectrophotometer U-4100 (trade name of Hitachi, Ltd.), the laminate is used as a sample to be measured. Then, the total light transmittance (light transmittance) of the sample when the total light transmittance of air is 100% is measured. The value of the total light transmittance (light transmittance) is the value measured at a wavelength of 550 nm.

In the laminate of the present invention, for example, the adhesive force or the adhesive force of the adhesive layer is 0.7 N
/ 25 mm or more, 0.8 N / 25 mm or more, 1.0 N / 25 mm or more, or 1.5 N /
25 mm or more, 50 N / 25 mm or less, 30 N / 25 mm or less, 10 N /
It may be 25 mm or less, 5 N / 25 mm or less, or 3 N / 25 mm or less. From the viewpoint of the risk of peeling during handling when the laminate is pasted with other layers, it is preferable that the adhesive force or adhesive force of the adhesive layer is not too low. Further, from the viewpoint of reworking at the time of re-adhesion, it is preferable that the adhesive force or the adhesive force of the adhesive layer is not too high. The adhesive force or adhesive force of the tacky adhesive layer can be measured, for example, as follows.

(Method of measuring adhesive strength or adhesive strength)
The laminated film of the present invention (on which the laminated body of the present invention is formed on a resin film substrate) is sampled in a strip shape of 50 mm × 140 mm, and the sample is fixed to a stainless plate with a double-sided tape. An adhesive tape piece obtained by sticking an acrylic adhesive layer (thickness 20 μm) on a PET film (T100: manufactured by Mitsubishi Plastics Film Co., Ltd.) and cutting the adhesive tape piece into 25 mm × 100 mm,
The laminated film of the present invention is laminated on the side opposite to the resin film and laminated with the PET film. Next, the sample was chucked in an autograph tensile tester (manufactured by Shimadzu Corporation: AG-Xplus) so that the chuck distance was 100 mm, and then a tensile test was performed at a tensile speed of 0.3 m / min. .. The average test force of the 50 mm peel test is defined as the adhesive peel strength, that is, the adhesive force. Also, the adhesive force can be measured by the same measuring method. In the present invention, there is no clear distinction between "adhesive strength" and "adhesive strength".

The laminate of the present invention may be formed on a substrate such as a film, for example. The film may be, for example, a resin film. Incidentally, in general, those having a relatively small thickness may be referred to as “film” and those having a relatively large thickness may be referred to as “sheet”, but in the present invention, “film” and “sheet” are referred to. There is no particular distinction.

The base material is not particularly limited, for example, a thermoplastic resin base material, a glass base material, an inorganic substrate represented by silicon, a plastic molded by a thermosetting resin or the like, an element such as a semiconductor, Carbon fiber materials represented by carbon nanotubes can be preferably used, but not limited to these. Examples of the form of the base material include a film and a plate. Examples of the thermoplastic resin include polyethylene terephthalate (PET), acrylic, cellulose acetate propionate (CAP), cycloolefin polymer (COP), triacetate (TAC), polyethylene naphthalate (PEN), polyethylene (PE), polypropylene. (PP) and the like.

The optical member of the present invention is not particularly limited, but may be, for example, an optical film including the laminate of the present invention.

The optical device (optical device) of the present invention is not particularly limited, and may be, for example, an image display device or a lighting device. Examples of the image display device include a liquid crystal display and an organic EL (E
retro Luminescence display, micro LED (Light)
An Emitting Diode display etc. are mentioned. Examples of the lighting device include organic EL lighting and the like.

[2. Void layer]
Hereinafter, the void layer in the laminate of the present invention (hereinafter, may be referred to as “void layer of the present invention”) will be described with reference to examples. However, the void layer of the present invention is not limited to this.

The void layer of the present invention has, for example, a porosity of 35% by volume or more and a peak pore size of 5
It may be 0 nm or less. However, this is merely an example, and the void layer of the present invention is not limited thereto.

The porosity may be, for example, 35% by volume or more, 38% by volume or more, or 40% by volume or more, and may be 90% by volume or less, 80% by volume or less, or 75% by volume or less.
The void layer of the present invention may be, for example, a high void layer having a void ratio of 60% by volume or more.

  The porosity can be measured, for example, by the following measuring method.

(Measurement method of porosity)
If the layer whose porosity is to be measured is a single layer and only contains voids, the ratio (volume ratio) of the constituent material of the layer and the volume of air can be calculated by a standard method (eg, weight and volume are measured to calculate the density). ), The porosity (volume%) can be calculated. Also,
Since the refractive index and the porosity have a correlation, the porosity can be calculated from the value of the refractive index of the layer, for example. Specifically, for example, from the value of the refractive index measured with an ellipsometer,
The porosity is calculated from Lorentz-Lorenz's formula (Lorenz-Lorenz formula).

The void layer of the present invention can be produced, for example, by chemical bonding of a crushed gel product (micropore particles) as described later. In this case, the voids of the void layer can be divided into the following three types (1) to (3) for convenience.

(1) Voids in the raw gel itself (inside the particles) (2) Voids in the crushed gel unit (3) Voids between crushed products caused by deposition of crushed gel products

The voids in (2) above are obtained when each particle group produced by crushing the gel is regarded as one lump (block), regardless of the size, size, etc. of the crushed gel (fine pore particles). In addition to the above (1) that can be formed in each block, it is a void that is formed during grinding. Further, the voids of the above (3) are voids caused by pulverization (for example, medialess pulverization) because the gel pulverized products (fine pore particles) have different sizes and sizes. The void layer of the present invention has, for example, the voids (1) to (3) described above, and thus has an appropriate void ratio and a peak pore diameter.

Further, the peak pore diameter may be, for example, 5 nm or more, 10 nm or more, or 20 nm or more, and may be 50 nm or less, 40 nm or less, or 30 nm or less. In the void layer, if the peak pore size is too large in the state where the void ratio is high, light is scattered and becomes opaque. In the present invention, the lower limit of the peak pore diameter of the void layer is not particularly limited, but if the peak pore diameter is too small, it becomes difficult to increase the porosity, so it is preferable that the peak pore diameter is not too small. In the present invention, the peak pore size can be measured, for example, by the following method.

(Peak pore size measurement method)
The peak pore diameter is calculated from the BJH plot and the BET plot by nitrogen adsorption and the isotherm adsorption line calculation results using a pore distribution / specific surface area measuring device (BELLSORP MINI / trade name of Microtrac Bell).

In addition, the void layer of the present invention contains nanoparticles surface-modified with a compound having surface orientation, as described above. The nanoparticles will be described in detail later. The void layer of the present invention may contain the nanoparticles in an amount of, for example, 10 to 50% by mass, 15 to 40% by mass, or 20 to 30% by mass based on the skeleton component of the void layer. The "skeleton component" in the void layer of the present invention is
It is the component having the highest mass among the components forming the void layer of the present invention other than air.
When the void layer of the present invention is a silicone porous body, the “skeleton component” in the void layer of the present invention is, for example, a condensation product of monoalkyl (trimethoxy) silane.

The thickness of the void layer of the present invention is not particularly limited, but is, for example, 100 nm or more, 20
0 nm or more, or 300 nm or more, 10,000 nm or less, 5000 nm
Or less, or 2000 nm or less.

The void layer of the present invention, for example, by using a pulverized product of a porous gel, as described below,
The three-dimensional structure of the porous gel is destroyed, and a new three-dimensional structure different from the porous gel is formed. As described above, the void layer of the present invention is a layer in which a new pore structure (new void structure), which cannot be obtained by the layer formed from the porous gel, is formed, and thus the void ratio is high. A void layer of scale can be formed. Further, in the void layer of the present invention, for example, when the void layer is a silicone porous body, for example, the pulverized products are chemically bound together while adjusting the number of siloxane-bonding functional groups of the silicon compound gel. In addition, after a new three-dimensional structure is formed as a precursor of the void layer, it is chemically bonded (for example, crosslinked) in the bonding step. In the case of a body, it has a structure having voids, but can maintain sufficient strength and flexibility. Therefore, according to the present invention, the void layer can be easily and simply applied to various objects.

The void layer of the present invention contains, for example, a pulverized product of a porous gel, and the pulverized products are chemically bonded to each other, as will be described later. In the void layer of the present invention, the form of chemical bond (chemical bond) between the pulverized products is not particularly limited, and specific examples of the chemical bond include cross-linking and the like. The method for chemically bonding the pulverized products is, for example, as described in detail in the above-mentioned method for manufacturing the void layer.

The cross-linking bond is, for example, a siloxane bond. Examples of the siloxane bond include the following T2 bond, T3 bond, and T4 bond. When the silicone porous material of the present invention has a siloxane bond, for example, it may have any one kind of bond, any two kinds of bond, or all three kinds of bond. Good. Of the siloxane bonds, the higher the ratio of T2 and T3, the more flexible the gel can be expected to have its original properties.
The film strength becomes weak. On the other hand, when the T4 ratio of the siloxane bonds is high, the film strength is likely to be exhibited, but the void size becomes small and the flexibility becomes brittle. Therefore, for example, it is preferable to change the T2, T3, T4 ratio according to the application.

When the void layer of the present invention has the siloxane bond, the ratio of T2, T3 and T4 is
For example, when T2 is relatively expressed as “1”, T2: T3: T4 = 1: [1 to 100
]: [0-50], 1: [1-80]: [1-40], 1: [5-60]: [1-30]
Is.

Further, in the void layer of the present invention, for example, it is preferable that the contained silicon atoms are siloxane-bonded. As a specific example, the proportion of unbonded silicon atoms (that is, residual silanol) in all the silicon atoms contained in the silicone porous body is, for example, less than 50%, 30% or less, and 15% or less.

The void layer of the present invention has, for example, a pore structure. In the present invention, the pore size of a hole refers to the major axis diameter of the major axis diameter and the minor axis diameter of the void (hole).
The pore size is, for example, 5 nm to 50 nm. The lower limit of the void size is, for example, 5 nm or more, 10 nm or more, 20 nm or more, and the upper limit thereof is, for example, 50 nm or less, 40 nm or less, 30 nm or less, and the range thereof is, for example, 5 nm to 50 nm, 10 nm.
nm to 40 nm. Since the preferred void size is determined depending on the use of the void structure, it is necessary to adjust the void size to a desired void size depending on the purpose. The void size can be evaluated, for example, by the following method.

(SEM observation of cross section of void layer)
In the present invention, the morphology of the void layer can be observed and analyzed using a SEM (scanning electron microscope). Specifically, for example, the void layer is subjected to FIB processing under cooling (accelerating voltage: 30 k
V), and about the obtained cross-section sample, FIB-SEM (made by FEI: brand name Helio
s NanoLab600, accelerating voltage: 1 kV), a cross-sectional electron image can be obtained at an observation magnification of 100,000 times.

(Evaluation of void size)
In the present invention, the void size can be quantified by the BET test method. In particular,
0.1 g of the sample (void layer of the present invention) was put into the capillary of a pore size distribution / specific surface area measuring device (BELLSORP MINI / trade name of Microtrack Bell Co., Ltd.), and vacuum drying was performed at room temperature for 24 hours. , Degassing the gas in the void structure. Then, by adsorbing nitrogen gas to the sample, a BET plot, a BJH plot, and an adsorption isotherm are drawn to determine the pore distribution. This allows the void size to be evaluated.

In the void layer of the present invention, the film density showing the porosity is not particularly limited, and the lower limit thereof is, for example, 1 g / cm ³ or more, 5 g / cm ³ or more, 10 g / cm ³ or more, 15 g / cm ³ or more. Yes, the upper limit thereof is, for example, 50 g / cm ³ or less, 40 g / cm ³ or less, 30 g / cm ³
Hereinafter, it is 2.1 g / cm ³ or less, and the range is, for example, 5 to 50 g / cm ³ , 10
^{40g / cm 3, 15~30g / cm} 3, a 1~2.1g / cm ^3.

  The film density can be measured, for example, by the following method.

(Evaluation of film density)
After forming a void layer (void layer of the present invention) on the acrylic film, an X-ray diffractometer (RIGA
The X-ray reflectance in the total reflection area was measured using RINT-2000 manufactured by KU. Inte
After performing the fitting of the nity and 2θ, the porosity (P%) is calculated from the critical angle of total reflection of the void layer / base material. The film density can be expressed by the following formula.
Film density (%) = 100 (%)-porosity (P%)

The void layer of the present invention may have a pore structure (porous structure) as described above,
For example, it may be an open-cell structure having continuous pore structures. The open cell structure means, for example, that the pore structure is three-dimensionally continuous in the void layer, and it can be said that the internal voids of the pore structure are continuous. When the porous body has an open cell structure, it is possible to increase the porosity occupied in the bulk, but when the closed cell particles such as hollow silica are used, the open cell structure cannot be formed. On the other hand, in the void layer of the present invention, since the sol particles (the pulverized product of the porous gel forming the sol) have a three-dimensional dendritic structure, the coating film (the pulverized product of the porous gel is It is possible to easily form an open cell structure by sedimentation and deposition of the dendritic particles in the sol containing coating film). Further, the void layer of the present invention more preferably forms a monolith structure in which the open cell structure has a plurality of pore distributions. The monolith structure refers to, for example, a structure having nano-sized fine voids and a hierarchical structure existing as an open cell structure in which the nano voids are aggregated. In the case of forming the monolith structure, for example, it is possible to provide the film strength with the fine voids and the high void ratio with the coarse open-cell voids, thereby achieving both the film strength and the high void ratio. In order to form such a monolith structure, for example, it is important to control the pore distribution of the void structure to be generated in the porous gel before the pulverization into the pulverized product. In addition, for example, when the porous gel is crushed, the monolith structure can be formed by controlling the particle size distribution of the crushed product to a desired size.

In the void layer of the present invention, haze indicating transparency is not particularly limited, and the lower limit thereof is, for example, 0.1% or more, 0.2% or more, 0.3% or more, and the upper limit thereof is, for example, 10% or less, 5% or less, 3% or less, and the range is, for example, 0.1 to 10%, 0.2 to 5%,
It is 0.3 to 3%.

  The haze can be measured, for example, by the following method.

(Haze evaluation)
The void layer (void layer of the present invention) is cut into a size of 50 mm × 50 mm and set in a haze meter (HM-150 manufactured by Murakami Color Research Laboratory Co., Ltd.) to measure haze. The haze value is calculated by the following formula.
Haze (%) = [diffuse transmittance (%) / total light transmittance (%)] × 100 (%)

The refractive index is generally the ratio of the propagation speed of the wavefront of light in vacuum to the propagation speed in the medium,
It is called the refractive index of the medium. The refractive index of the void layer of the present invention is not particularly limited, and its upper limit is, for example, 1.3 or less, less than 1.3, 1.25 or less, 1.2 or less, 1.15 or less, and its lower limit. Is, for example, 1.05 or more, 1.06 or more, 1.07 or more, and the range is, for example, 1.05 or more and 1.3 or less, 1.05 or more and less than 1.3, 1.05 or more 1 0.25 or less, 1
． It is 06 or more and less than 1.2, and 1.07 or more and 1.15 or less.

In the present invention, the refractive index means a refractive index measured at a wavelength of 550 nm, unless otherwise specified. The method for measuring the refractive index is not particularly limited, and for example, it can be measured by the following method.

(Evaluation of refractive index)
After forming a void layer (void layer of the present invention) on an acrylic film, it is cut into a size of 50 mm × 50 mm, and this is stuck to the surface of a glass plate (thickness: 3 mm) with an adhesive layer. A central portion of the back surface of the glass plate (diameter of about 20 mm) is painted with black magic to prepare a sample that does not reflect on the back surface of the glass plate. Ellipsometer (JA Woollam J
apan company: VASE), and set the sample to a wavelength of 500 nm and an incident angle of 50 to 50 nm.
The refractive index is measured under the condition of 80 degrees, and the average value is taken as the refractive index.

The thickness of the void layer of the present invention is not particularly limited, and its lower limit is, for example, 0.05 μm or more,
It is 0.1 μm or more, and the upper limit thereof is, for example, 1000 μm or less and 100 μm or less, and the range thereof is, for example, 0.05 to 1000 μm, 0.1 to 100 μm.

The form of the void layer of the present invention is not particularly limited and may be, for example, a film shape or a block shape.

The method for producing the void layer of the present invention is not particularly limited, but it can be produced, for example, by the production method described below.

[3. Nanoparticles whose surface is modified with a compound having surface orientation]
As described above, the void layer of the present invention contains a compound having surface orientation.

The compound having surface orientation may contain, for example, a fluoroalkyl group having 5 to 17 or 5 to 10 fluorine atoms. The fluoroalkyl group may be an alkyl group in which only part of hydrogen is replaced with fluorine, or may be an alkyl group in which all hydrogen is replaced with fluorine (perfluoroalkyl group). Further, the fluoroalkyl group may be, for example, a fluoroalkyl group containing a perfluoroalkyl group in a part of its structure. The alkyl group in the fluoroalkyl group is not particularly limited, but has, for example, 2 to 1 carbon atoms.
0 straight-chain or branched alkyl groups are mentioned.

In addition, as described above, for example, the compound having surface orientation is an alkoxysilane derivative, and the alkoxysilane derivative may include a fluoroalkyl group having 5 to 17 or 5 to 10 fluorine atoms. .. The fluoroalkyl group may be an alkyl group in which only part of hydrogen is replaced with fluorine, or may be an alkyl group in which all hydrogen is replaced with fluorine (perfluoroalkyl group). Further, the fluoroalkyl group may be, for example, a fluoroalkyl group containing a perfluoroalkyl group in a part of its structure. The alkyl group in the fluoroalkyl group is not particularly limited, but as described above, for example,
A straight chain or branched alkyl group having 2 to 10 carbon atoms can be mentioned.

The alkoxysilane derivative may be, for example, a derivative of monoalkoxysilane, dialkoxysilane, trialkoxysilane, or tetraalkoxysilane. More specifically, it may be a derivative in which one or more alkyl groups in the alkoxy group in one molecule of the alkoxysilane are replaced with the fluoroalkyl group. The alkyl group in the fluoroalkyl group is as described above, for example. In the molecule of the alkoxysilane derivative, the alkoxy group in which the alkyl group is not replaced with the fluoroalkyl group is not particularly limited, and examples thereof include a linear or branched alkyl group having 1 to 4 carbon atoms, For example, it may be a methoxy group or the like. As the alkoxysilane derivative,
Specifically, for example, trimethoxy (1H, 1H, 2H, 2H-nonafluorohexyl)
Silane, trimethoxy (1H, 1H, 2H, 2H-heptadecafluorodecyl) silane,
Examples thereof include triethoxy [5,5,6,6,7,7,7-heptafluoro-4,4-bis (trifluoromethyl) heptyl] silane. Further, the alkoxysilane derivative,
Only one kind may be used, or plural kinds may be used in combination.

Further, as an example of the compound having the surface orientation, other than the alkoxysilane derivative, for example, has a perfluoro group, and further has a hydrophilic site and a hydrophobic site such as a hydroxyl group and a sodium sulfonate group at the terminal. Examples thereof include a surfactant containing one in one structure.

The nanoparticles are not particularly limited, but may be, for example, silica particles, and more specifically, for example, may be pulverized products of a silicon compound gel as described below. The particle diameter of the nanoparticles is not particularly limited, but for example, the volume average particle diameter is 1 nm or more, 2 nm or more,
3 nm or more, or 5 nm or more, 1000 nm or less, 500 nm or less, 2
It may be 00 nm or less, or 50 nm or less. The volume average particle diameter is, for example, a particle size distribution evaluation device such as a dynamic light scattering method or a laser diffraction method, and a scanning electron microscope (S
EM), an electron microscope such as a transmission electron microscope (TEM), and the like.

The method of modifying the nanoparticles with the compound having the surface orientation is not particularly limited, and, for example, a known method can be appropriately used. More specifically, for example, the nanoparticles and the compound having the surface orientation may be heated and reacted in a liquid. The medium (dispersion medium) in the liquid is not particularly limited, and examples thereof include water and alcohol,
You may use only 1 type and may use multiple types together. Examples of the alcohol include IPA
(Isopropyl alcohol), IBA (isobutyl alcohol), ethanol, methanol, etc. may be mentioned, and other than the alcohols such as MIBK (methyl isobutyl ketone) and MEK (methyl ethyl ketone) may be included. The reaction temperature and reaction time of the reaction are not particularly limited and can be set appropriately.

[4. Method for manufacturing void layer and laminate]
The method for producing the void layer and the laminate of the present invention is not particularly limited, but for example, it can be performed by the production method described below. However, the following description is an example, and does not limit the present invention. In addition, below, the method of manufacturing the void layer of this invention may be called "the manufacturing method of the void layer of this invention."

[4-1. Method for manufacturing void layer]
Hereinafter, the method for producing the void layer of the present invention will be described with reference to examples. However, the method for producing the void layer of the present invention is not limited to the following description.

The void layer of the present invention may be formed of, for example, a silicon compound. Further, the void layer of the present invention may be, for example, a void layer formed by chemical bonding of fine pore particles. For example, the fine pore particles may be a crushed product of gel. Then, the void layer of the present invention may include, for example, in addition to the skeleton formed by the chemical bond between the fine pore particles, the nanoparticles surface-modified with the compound having the surface orientation.

In the method for producing a void layer of the present invention, for example, the gel pulverizing step for pulverizing the gel of the porous body may be performed in one step, but is preferably performed in a plurality of pulverizing steps. The number of crushing steps is not particularly limited and may be, for example, two steps or three or more steps.

In the present invention, the shape of the “particle” (for example, the particle of the crushed gel product) is not particularly limited, and may be, for example, spherical or non-spherical. In the present invention,
The particles of the pulverized product may be, for example, sol-gel beaded particles, nanoparticles (hollow nanosilica / nanoballoon particles), nanofibers, or the like.

In the present invention, for example, the gel is preferably a porous gel, and the pulverized product of the gel is preferably porous, but is not limited thereto.

In the present invention, the crushed gel product may have a structure having at least one of a particle shape, a fiber shape, and a flat plate shape. The particulate and flat structural units may be made of, for example, an inorganic material. Further, the constituent elements of the particulate structural unit, for example,
It may contain at least one element selected from the group consisting of Si, Mg, Al, Ti, Zn and Zr. The structure (constituent unit) that forms the particles may be real particles or hollow particles, and specific examples thereof include silicone particles, silicone particles having fine pores, silica hollow nanoparticles and silica hollow nanoballoons. The fibrous structural unit is, for example, a nanofiber having a diameter of nanosize, and specific examples thereof include cellulose nanofiber and alumina nanofiber. Examples of the flat-plate constitutional unit include nanoclays, and specifically nano-sized bentonite (for example, Kunipia F [trade name]) and the like. The fibrous structural unit is not particularly limited, for example, from the group consisting of carbon nanofibers, cellulose nanofibers, alumina nanofibers, chitin nanofibers, chitosan nanofibers, polymer nanofibers, glass nanofibers, and silica nanofibers. It may be at least one fibrous material selected.

In the method for producing a void layer of the present invention, the gel crushing step (for example, the plurality of crushing steps, for example, the first crushing step and the second crushing step) is performed, for example, in the “other solvent”. You may go in. The details of the "other solvent" will be described later.

In the present invention, the “solvent” (eg, a solvent for gel production, a solvent for void layer production, a solvent for substitution, etc.) does not have to dissolve the gel or a pulverized product thereof, and for example, the gel or the gel thereof. The pulverized product may be dispersed or precipitated in the solvent.

The volume average particle diameter of the gel after the first crushing step is, for example, 0.5 to 100 μm,
It may be 1 to 100 μm, 1 to 50 μm, 2 to 20 μm, or 3 to 10 μm. The volume average particle diameter of the gel after the second pulverization step is, for example, 10 to 1000 nm, 10
It may be 0 to 500 nm, or 200 to 300 nm. The volume average particle diameter indicates the particle size variation of the pulverized product in the gel-containing liquid (gel-containing liquid). The volume average particle diameter may be measured by, for example, a particle size distribution evaluation device such as a dynamic light scattering method or a laser diffraction method, and an electron microscope such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM). You can

The method for producing a void layer of the present invention includes, for example, a gelling step of gelling a lump-like porous body in a solvent to form the gel. In this case, for example, in the first crushing step (for example, the first crushing step) of the plurality of crushing steps, the gel gelled by the gelling step is used.

The method for producing a void layer of the present invention includes, for example, an aging step of aging the gelled gel in a solvent. In this case, for example, the first grinding step (for example,
In the first crushing step), the gel after the aging step is used.

In the method for producing a void layer of the present invention, for example, after the gelling step, the solvent substitution step of substituting the solvent with another solvent is performed. In this case, for example, the gel in the other solvent is used in the first crushing step (for example, the first crushing step) of the plurality of crushing steps.

In at least one of the plurality of pulverizing stages (for example, at least one of the first pulverizing stage and the second pulverizing stage) of the method for producing a void layer of the present invention, for example, the shear viscosity of the liquid is measured. While controlling the pulverization of the porous body.

At least one of the plurality of pulverizing stages (for example, at least one of the first pulverizing stage and the second pulverizing stage) of the method for producing a void layer of the present invention is performed by, for example, high pressure medialess pulverizing.

In the method for producing a void layer of the present invention, the gel is, for example, a silicon compound gel containing at least a trifunctional or lower saturated bond functional group.

Hereinafter, in the method for producing a void layer of the present invention, the gel pulverized material-containing liquid obtained by the step including the gel pulverization step may be referred to as “the gel pulverized material-containing liquid of the present invention”.

According to the gel pulverized product-containing liquid of the present invention, for example, by forming the coating film and chemically binding the pulverized products in the coating film, the present invention as a functional porous body is obtained. A void layer can be formed. According to the liquid containing a crushed gel product of the present invention, for example, the void layer of the present invention can be applied to various objects. Therefore, the pulverized gel-containing liquid of the present invention and the method for producing the same are useful, for example, in the production of the void layer of the present invention.

The pulverized gel-containing liquid of the present invention has, for example, extremely excellent homogeneity, and therefore, for example, when the void layer of the present invention is applied to applications such as optical members, the appearance thereof is improved. be able to.

The gel pulverized material-containing liquid of the present invention is, for example, for coating (coating) the gel pulverized material-containing liquid on a substrate and further drying it to obtain a layer having a high porosity (void layer), It may be a liquid containing a crushed gel. The pulverized gel-containing liquid of the present invention may be, for example, a pulverized gel-containing liquid for obtaining a high porosity porous body (thick or bulky bulk body). The bulk body can be obtained, for example, by performing bulk film formation using the gel pulverized product-containing liquid.

For example, a step of producing the gel pulverized material-containing liquid of the present invention, a step of adding nanoparticles surface-modified with the compound having the surface orientation to the gel pulverized material-containing liquid, and coating it on a substrate. By a manufacturing method including a step of forming a coating film by drying, and a step of drying the coating film,
The void layer of the present invention having a high porosity can be produced.

Further, for example, a step of producing the gel pulverized material-containing liquid of the present invention, a step of paying out the resin film in a roll shape, and a coating by applying the gel crushed material-containing liquid to the paid out resin film. By a manufacturing method including a step of forming a film, a step of drying the coating film, and a step of winding the laminated film in which the void layer of the present invention is formed on the resin film after the drying step. For example, a roll-shaped laminated film (laminated film roll) can be produced as shown in the following items 2 and 3.

[4-2. Liquid containing crushed gel and its manufacturing method]
The gel pulverized product-containing liquid of the present invention contains, for example, a pulverized product of gel pulverized by the gel pulverizing step (for example, the first pulverizing step and the second pulverizing step) and the other solvent.

The method for producing a void layer of the present invention may include, for example, as described above, a gel crushing step for crushing the gel (for example, a porous gel) in a plurality of stages, for example, the first crushing. And a second crushing step. Hereinafter, the case where the method for producing a pulverized gel-containing liquid of the present invention mainly includes the first pulverizing step and the second pulverizing step will be described as an example. Hereinafter, the case where the gel is a porous body (porous gel) will be mainly described. However, the present invention is not limited to this, and the description about the case where the gel is a porous body (porous gel) can be applied by analogy, other than when the gel is a porous body. In addition, hereinafter, the plurality of crushing steps (for example, the first crushing step and the second
The crushing step) is sometimes referred to as a “gel crushing step”.

The pulverized gel-containing liquid of the present invention can be used, for example, for producing a functional porous body having a function similar to that of an air layer (for example, low refractive index), as described later. The functional porous body, for example,
It may be the void layer of the present invention. Specifically, the gel pulverized product-containing liquid obtained by the production method of the present invention contains the pulverized product of the porous gel, and the pulverized product has a three-dimensional structure of the unpulverized porous gel destroyed. A new three-dimensional structure different from that of the unground porous gel can be formed. Therefore, for example, a coating film (precursor of a functional porous body) formed by using the gel pulverized product-containing liquid is not obtained in a layer formed by using the unpulverized porous gel. The layer has a pore structure (new void structure). This allows the layer to have the same function as the air layer (for example, the same low refractive index). In addition, the gel pulverized product-containing liquid of the present invention, for example, after the pulverized product contains a residual silanol group, a new three-dimensional structure is formed as the coating film (precursor of the functional porous body). The crushed products can be chemically bonded to each other. Thereby, the formed functional porous body has a structure having voids, but can maintain sufficient strength and flexibility. Therefore, according to the present invention, the functional porous body can be easily and simply applied to various objects. The pulverized gel-containing liquid obtained by the production method of the present invention is very useful, for example, in producing the porous structure that can be a substitute for the air layer. Further, in the case of the air layer, it is necessary to form the air layer between the members by, for example, stacking the members and the members with a gap between them to provide a gap therebetween. However, the functional porous body formed by using the crushed gel-containing liquid of the present invention can exhibit the same function as that of the air layer only by disposing the functional porous body at a target site. Therefore, as described above, various objects can be provided with a function similar to that of the air layer more easily and simply than when the air layer is formed.

The pulverized gel-containing liquid of the present invention can be referred to as, for example, a solution for forming the functional porous body or a solution for forming a void layer or a low refractive index layer. In the liquid containing a crushed gel product of the present invention, the porous body is a crushed product.

In the gel crushed product-containing liquid of the present invention, the range of the volume average particle size of the crushed product (particles of the porous gel) is, for example, 10 to 1000 nm, 100 to 500 nm, and 200 to 30.
It is 0 nm. The volume average particle diameter indicates the particle size variation of the crushed product in the gel crushed product-containing liquid of the present invention. As described above, the volume average particle diameter is, for example, a particle size distribution evaluation device such as a dynamic light scattering method or a laser diffraction method, and an electron microscope such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM). Can be measured by

In the liquid containing a pulverized product of the present invention, the gel concentration of the pulverized product is not particularly limited, and for example, particles having a particle diameter of 10 to 1000 nm are 2.5 to 4.5% by weight and 2.7 to. It is 4.0% by weight and 2.8 to 3.2% by weight.

In the liquid containing a crushed gel product of the present invention, the gel (for example, a porous gel) is not particularly limited, and examples thereof include a silicon compound.

The silicon compound is not particularly limited, but examples thereof include a silicon compound containing a saturated bond functional group having at least trifunctionality. The above-mentioned "including a saturated bond functional group of 3 functional groups or less" means that the silicon compound has 3 or less functional groups, and these functional groups are silicon (Si
) Is a saturated bond with.

The silicon compound is, for example, a compound represented by the following formula (2).

In the formula (2), for example, X is 2, 3 or 4,
R ¹ and R ² are each a linear or branched alkyl group,
R ¹ and R ² may be the same or different,
R ¹ may be the same or different from each other when X is 2.
R ² may be the same or different from each other.

The X and R ¹ are, for example, the same as X and R ¹ in the formula (1). Further, as the R ² , for example, the example of R ¹ in the formula (1) described later can be cited.

Specific examples of the silicon compound represented by the formula (2) include compounds represented by the following formula (2 ′) in which X is 3. In the following formula (2 ′), R ¹ and R ² are respectively the same as in the above formula (2). When R ¹ and R ² are methyl groups, the silicon compound is trimethoxy (methyl) silane (hereinafter, also referred to as “MTMS”).

In the crushed gel-containing liquid of the present invention, examples of the solvent include a dispersion medium. The dispersion medium (hereinafter, also referred to as “coating solvent”) is not particularly limited, and examples thereof include a gelling solvent and a pulverizing solvent described later, and the pulverizing solvent is preferable. The coating solvent includes an organic solvent having a boiling point of 70 ° C. or higher and lower than 180 ° C. and a saturated vapor pressure at 20 ° C. of 15 kPa or lower.

Examples of the organic solvent include carbon tetrachloride, 1,2-dichloroethane, 1,1,2,
2-tetrachloroethane, trichloroethylene, isobutyl alcohol, isopropyl alcohol, isopentyl alcohol, 1-pentyl alcohol (pentanol), ethyl alcohol (ethanol), ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol mono-normal -Butyl ether, ethylene glycol monomethyl ether, xylene, cresol, chlorobenzene, isobutyl acetate, isopropyl acetate, isopentyl acetate, ethyl acetate, normal-butyl acetate, normal-propyl acetate, normal-pentyl acetate, cyclohexanol, cyclohexanone, 1,4- Dioxane, N, N-dimethylformamide, styrene, tetrachloroethylene, 1,1,1-to Chloroethane, toluene, 1-butanol, 2-butanol, methyl isobutyl ketone, methyl ethyl ketone, methyl cyclohexanol, methyl cyclohexanone, methyl - n - butyl ketone, iso-pentanol, and the like. Further, the dispersion medium may contain an appropriate amount of a perfluoro-based surfactant, a silicon-based surfactant, or the like that lowers the surface tension.

Examples of the pulverized gel-containing liquid of the present invention include a sol particle liquid which is the sol-like pulverized product dispersed in the dispersion medium. The crushed gel-containing liquid of the present invention is applied, for example, to a substrate by coating /
After drying, chemical bonding is performed in the bonding step described below, whereby a void layer having a film strength of a certain level or higher can be continuously formed. In addition, the "sol" in the present invention means that a pulverized product (that is, particles of a porous sol having a nano three-dimensional structure which retains a part of a void structure) is obtained by pulverizing a three-dimensional structure of a gel in a solvent. It means a state of being dispersed in and exhibiting fluidity.

The gel pulverized material-containing liquid of the present invention may include, for example, a catalyst for chemically bonding the pulverized gel materials. The content of the catalyst is not particularly limited, but is, for example, 0.01 to 20% by weight, 0.05 to 10% by weight, or 0.
It is 1 to 5% by weight.

The pulverized gel-containing solution of the present invention may further contain, for example, a cross-linking aid for indirectly binding the pulverized gels to each other. The content of the crosslinking aid is not particularly limited, but is, for example, 0.01 to 20% by weight, and 0.0 to 20% by weight based on the weight of the pulverized product of the gel.
It is 5 to 15% by weight, or 0.1 to 10% by weight.

In the liquid containing a pulverized gel of the present invention, the ratio of the functional groups not contributing to the in-gel cross-linking structure in the functional groups of the constituent monomer of the gel is, for example, 30 mol% or less, 25 mol.
% Or less, 20 mol% or less, 15 mol% or less, for example, 1 mol% or more, 2 mol% or more, 3 mol% or more, 4 mol% or more. The ratio of the functional groups that do not contribute to the in-gel crosslinked structure can be measured, for example, as follows.

(Measurement method of the proportion of functional groups that do not contribute to the crosslinked structure in the gel)
After the gel is dried, solid-state NMR (Si-NMR) is measured, and the ratio of residual silanol groups not contributing to the crosslinked structure (functional groups not contributing to the crosslinked structure in the gel) is calculated from the NMR peak ratio. Even when the functional group is other than the silanol group, the proportion of the functional group that does not contribute to the in-gel crosslinked structure can be calculated from the NMR peak ratio in accordance with this.

The method for producing the pulverized gel-containing liquid of the present invention will be described below with reference to examples. The crushed gel-containing liquid of the present invention can be incorporated by the following explanations unless otherwise specified.

In the method for producing a liquid containing a crushed gel product of the present invention, the mixing step includes the particles of the porous gel (
This is a step of mixing a pulverized product) with the solvent, which may or may not be present. As a specific example of the mixing step, for example, a step of mixing a pulverized product of a gel-like silicon compound (silicon compound gel) obtained from a silicon compound containing at least a trifunctional or less saturated bond functional group with a dispersion medium is used. Can be mentioned. In the present invention, the pulverized product of the porous gel can be obtained from the porous gel by the gel pulverization step described below. Further, the pulverized product of the porous gel,
For example, it can be obtained from the porous gel after the aging treatment in which the aging step described below is performed.

In the method for producing a crushed gel-containing liquid of the present invention, the gelling step is, for example, a step of gelling a lumpy porous body in a solvent to form the porous gel, and specific examples of the gelling step include For example, it is a step of forming a silicon compound gel by gelling the silicon compound containing at least the trifunctional or less saturated bond functional group in a solvent.

Hereinafter, the gelation step will be described by taking the case where the porous body is a silicon compound as an example.

The gelling step, for example, the silicon compound of the monomer, in the presence of a dehydration condensation catalyst,
This is a step of gelation by dehydration condensation reaction, whereby a silicon compound gel is obtained. The silicon compound gel has, for example, a residual silanol group, and the residual silanol group is preferably adjusted appropriately according to the chemical bonding between the pulverized products of the silicon compound gel described later.

In the gelling step, the silicon compound is not particularly limited as long as it gels by a dehydration condensation reaction. By the dehydration condensation, for example, the silicon compounds are bound to each other. The bond between the silicon compounds is, for example, a hydrogen bond or an intermolecular force bond.

Examples of the silicon compound include silicon compounds represented by the following formula (1). Since the silicon compound of the above formula (1) has a hydroxyl group, between the silicon compounds of the above formula (1),
For example, hydrogen bond or intermolecular force bond is possible through each hydroxyl group.

In the above formula (1), for example, X is 2, 3 or 4, and R ¹ is a linear or branched alkyl group. The carbon number of R ¹ is, for example, ¹ to 6, ^{1 to 4} , or ^{1 to 2} . The linear alkyl group is, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group,
Examples thereof include a hexyl group, and examples of the branched alkyl group include an isopropyl group and an isobutyl group. The X is, for example, 3 or 4.

Specific examples of the silicon compound represented by the formula (1) include compounds represented by the following formula (1 ′) in which X is 3. In the following formula (1 ′), R ¹ is the same as in the above formula (1), and is, for example, a methyl group. When R ¹ is a methyl group, the silicon compound is tris (hydroxy) methylsilane. When X is 3, the silicon compound is, for example, a trifunctional silane having three functional groups.

Specific examples of the silicon compound represented by the above formula (1) include compounds in which X is 4. In this case, the silicon compound is, for example, 4 having 4 functional groups.
It is a functional silane.

The silicon compound may be, for example, a precursor that forms the silicon compound of the formula (1) by hydrolysis. The precursor may be, for example, one capable of producing the silicon compound by hydrolysis, and specific examples thereof include the compound represented by the formula (2).

When the silicon compound is the precursor represented by the formula (2), the production method of the present invention may include, for example, a step of hydrolyzing the precursor prior to the gelation step.

The hydrolysis method is not particularly limited, and can be performed by, for example, a chemical reaction in the presence of a catalyst. Examples of the catalyst include acids such as oxalic acid and acetic acid. The hydrolysis reaction can be carried out, for example, by slowly dropping an aqueous solution of oxalic acid into the dimethylsulfoxide solution of the silicon compound precursor in a room temperature environment, and then stirring for about 30 minutes. When the silicon compound precursor is hydrolyzed, for example, by completely hydrolyzing the alkoxy group of the silicon compound precursor, subsequent gelation, aging, heating and immobilization after formation of a void structure, It can be efficiently expressed.

In the present invention, the silicon compound may be, for example, a hydrolyzate of trimethoxy (methyl) silane.

The silicon compound as the monomer is not particularly limited and can be appropriately selected depending on, for example, the use of the functional porous body to be produced. In the production of the functional porous body, the silicon compound is
For example, when low refractive index is important, the trifunctional silane is preferable from the viewpoint of excellent low refractive index, and when strength (for example, scratch resistance) is important, scratch resistance is excellent. ,
The tetrafunctional silane is preferred. In addition, the silicon compound, which is a raw material of the silicon compound gel, may be used alone or in combination of two or more kinds. As a specific example, the silicon compound may include, for example, only the trifunctional silane, may include only the tetrafunctional silane, or may include both the trifunctional silane and the tetrafunctional silane, Further, it may contain other silicon compounds. As the silicon compound,
When two or more kinds of silicon compounds are used, the ratio is not particularly limited and can be set appropriately.

The gelation of the porous material such as the silicon compound can be performed by, for example, a dehydration condensation reaction between the porous materials. The dehydration condensation reaction is preferably carried out, for example, in the presence of a catalyst, and examples of the catalyst include acid catalysts such as hydrochloric acid, oxalic acid and sulfuric acid, and ammonia, potassium hydroxide, sodium hydroxide, ammonium hydroxide and the like. And a dehydration condensation catalyst such as a base catalyst of. The dehydration condensation catalyst may be an acid catalyst or a base catalyst, but a base catalyst is preferred.
In the dehydration condensation reaction, the amount of the catalyst added to the porous body is not particularly limited,
The catalyst is, for example, 0.01 to 10 mol, 0.05 to 7 mol, relative to 1 mol of the porous body.
It is 0.1 to 5 mol.

The gelation of the porous material such as the silicon compound is preferably performed in a solvent, for example. The ratio of the porous body in the solvent is not particularly limited. Examples of the solvent include dimethyl sulfoxide (DMSO), N-methylpyrrolidone (NMP), N, N-dimethylacetamide (DMAc), dimethylformamide (DMF), γ-butyl lactone (GBL),
Acetonitrile (MeCN), ethylene glycol ethyl ether (EGEE) and the like can be mentioned. The solvent may be, for example, one kind or a combination of two or more kinds. Hereinafter, the solvent used for the gelation is also referred to as “gelling solvent”.

The conditions for gelation are not particularly limited. The treatment temperature for the solvent containing the porous body is, for example, 20 to 30 ° C., 22 to 28 ° C., and 24 to 26 ° C., and the treatment time is, for example,
It is 1 to 60 minutes, 5 to 40 minutes, and 10 to 30 minutes. When the dehydration condensation reaction is performed, the treatment conditions are not particularly limited, and these examples can be applied. By performing the gelation, when the porous body is a silicon compound, for example, a siloxane bond grows, primary particles of the silicon compound are formed, further reaction proceeds, the primary particles are, A gel having a three-dimensional structure is formed in a beaded manner.

The gel form of the porous body obtained in the gelation step is not particularly limited. The “gel” generally means a solidified state in which solutes have a structure in which solutes lose their independent motility due to an interaction and are assembled. In addition, among the gel, generally, the wet gel contains a dispersion medium,
The solute has a uniform structure in the dispersion medium, and the xerogel has a network structure in which the solute has voids after the solvent is removed. In the present invention, the silicon compound gel is
For example, it is preferable to use wet gel. When the porous gel is a silicon compound gel, the residual silanol group of the silicon compound gel is not particularly limited, and for example, the range described below can be similarly exemplified.

The porous gel obtained by the gelation may be subjected to, for example, the solvent replacement step and the first pulverizing step as it is. However, prior to the first pulverizing step, an aging treatment is performed in the aging step. May be given. In the aging step, the gelled porous body (porous body gel)
Is aged in a solvent. In the aging step, the conditions for the aging treatment are not particularly limited,
For example, the porous gel may be incubated in a solvent at a predetermined temperature. According to the aging treatment, for example, with respect to the porous gel having a three-dimensional structure obtained by gelation, the primary particles can be further grown, whereby the size of the particles themselves can be increased. is there. As a result, the contact state of the neck portion where the particles are in contact with each other can be increased from, for example, point contact to surface contact. In the porous gel subjected to the aging treatment as described above, for example, the strength of the gel itself is increased, and as a result, the strength of the three-dimensional basic structure of the crushed product after crushing can be further improved. Thereby, when a coating film is formed using the gel pulverized product-containing liquid of the present invention, for example, even in the drying step after coating, the pore size of the void structure in which the three-dimensional basic structure is deposited is It is possible to suppress shrinkage due to volatilization of the solvent in the coating film that occurs in the drying step.

Regarding the temperature of the aging treatment, the lower limit thereof is, for example, 30 ° C. or higher, 35 ° C. or higher, 40 ° C. or higher, and the upper limit thereof is, for example, 80 ° C. or lower, 75 ° C. or lower, 70 ° C. or lower, and the range thereof is ,
For example, it is 30 to 80 ° C, 35 to 75 ° C, and 40 to 70 ° C. The predetermined time is not particularly limited, and the lower limit is, for example, 5 hours or more, 10 hours or more, 15 hours or more, and the upper limit is, for example, 50 hours or less, 40 hours or less, 30 hours or less. The range is, for example, 5 to 50 hours, 10 to 40 hours, and 15 to 30 hours. The optimum conditions for aging are preferably set, for example, as described above, so that the size of the primary particles in the porous gel is increased and the contact area of the neck portion is increased. .. Further, in the aging step, the temperature of the aging treatment preferably takes into consideration, for example, the boiling point of the solvent used. The aging treatment, for example, if the aging temperature is too high, the solvent is excessively volatilized, the concentration of the coating solution, there is a possibility that such a problem that the pores of the three-dimensional void structure is closed. is there. On the other hand, in the aging treatment, for example, if the aging temperature is too low, the effect of the aging cannot be sufficiently obtained, and the temperature variation over time in the mass production process will increase, which may result in a product of poor quality. There is.

For the aging treatment, for example, the same solvent as in the gelation step can be used, and specifically, the reaction product after the gel treatment (that is, the solvent containing the porous gel) can be directly applied. preferable. When the porous gel is the silicon compound gel, the number of moles of residual silanol groups contained in the silicon compound gel that has been aged after gelation is, for example, the raw material used for gelation (for example, the above It is the ratio of residual silanol groups when the number of moles of alkoxy groups of the silicon compound or its precursor) is 100, and the lower limit thereof is, for example, 50%.
The above is 40% or more and 30% or more, and the upper limit thereof is, for example, 1% or less, 3% or less, 5%
It is below, and the range is 1 to 50%, 3 to 40%, and 5 to 30%, for example. For the purpose of increasing the hardness of the silicon compound gel, for example, the lower the number of moles of residual silanol groups, the more preferable. If the number of residual silanol groups is too high, for example, in the formation of the functional porous body, the void structure may not be retained before the precursor of the functional porous body is crosslinked. On the other hand, if the number of residual silanol groups is too low, for example, the precursor of the functional porous body cannot be crosslinked in the bonding step, and sufficient film strength may not be imparted. Incidentally, the above is an example of residual silanol groups, for example, when the silicon compound modified with various reactive functional groups is used as the raw material of the silicon compound gel, for each functional group, Also, the same phenomenon can be applied.

The porous gel obtained by the gelation is, for example, subjected to an aging treatment in the aging step, then subjected to a solvent replacement step, and then subjected to the gel crushing step. In the solvent replacement step, the solvent is replaced with another solvent.

In the present invention, the gel crushing step is a step of crushing the porous gel as described above. The pulverization may be performed, for example, on the porous gel after the gelation step, or may be further performed on the aged porous gel after the aging treatment.

Further, as described above, a gel morphology control step of controlling the shape and size of the gel may be performed prior to the solvent replacement step (for example, after the aging step). The shape and size of the gel controlled in the gel morphology control step are not particularly limited, but are as described above, for example. The gel morphology control step may be performed, for example, by dividing (for example, dividing) the gel into a solid (three-dimensional body) having an appropriate size and shape.

Further, as described above, the gel replacement step is performed after the solvent replacement step is performed on the gel. In the solvent replacement step, the solvent is replaced with another solvent. If the solvent is not replaced with the other solvent, for example, the catalyst and the solvent used in the gelation step remain after the aging step, resulting in gelation over time and finally obtained gel pulverization. This is because the pot life of the substance-containing liquid may be affected, and the drying efficiency at the time of drying the coating film formed using the crushed gel-containing liquid may decrease. The other solvent in the gel crushing step is also referred to as "crushing solvent" hereinafter.

The grinding solvent (other solvent) is not particularly limited, and for example, an organic solvent can be used. The organic solvent has, for example, a boiling point of 140 ° C. or lower, 130 ° C. or lower, a boiling point of 100 ° C. or lower, a boiling point of 85.
A solvent at a temperature of not higher than 0 ° C is included. As a specific example, for example, isopropyl alcohol (IPA
), Ethanol, methanol, n-butanol, 2-butanol, isobutyl alcohol, pentyl alcohol, propylene glycol monomethyl ether (PGME), methyl cellosolve, acetone and the like. The grinding solvent may be, for example, one kind,
Two or more types may be used in combination.

Further, when the polarity of the pulverizing solvent is low, for example, the solvent replacement step is carried out by dividing it into a plurality of solvent replacement steps, and in the solvent replacement step, the step performed later is more than the step performed earlier. Alternatively, the hydrophilicity of the other solvent may be lowered. By doing this,
For example, it is possible to improve the efficiency of solvent substitution and to make the residual amount of the gel-producing solvent (for example, DMSO) in the gel extremely low. As a specific example, for example, the solvent replacement step is divided into three solvent replacement steps, and in the first solvent replacement step, DMSO in the gel is first replaced with water, and then the second solvent replacement step is performed. Then, the water in the gel may be replaced with IPA, and the IPA in the gel may be replaced with isobutyl alcohol in the third replacement step.

The combination of the gelling solvent and the pulverizing solvent is not particularly limited, and may be, for example, DMSO.
And IPA, DMSO and ethanol, DMSO and isobutyl alcohol, DMSO and n-butanol, and the like. Thus, by replacing the gelling solvent with the crushing solvent, for example, in the coating film formation described below,
A more uniform coating film can be formed.

The solvent replacement step is not particularly limited, but can be performed as follows, for example. That is, first, a gel produced by the gel production step (for example, the gel after the aging treatment) is immersed in or in contact with the other solvent, a catalyst for gel production in the gel, an alcohol component produced by a condensation reaction. , Water and the like are dissolved in the other solvent. After that, the solvent in which the gel has been dipped or contacted is discarded, and the gel is dipped or contacted again with a new solvent. This is repeated until the residual amount of the gel-producing solvent in the gel reaches a desired amount. The immersion time per time is, for example, 0.5 hours or more, 1 hour or more, or 1.5 hours or more, and the upper limit value is not particularly limited, but is 10 hours or less, for example. Further, the immersion of the solvent may be carried out by continuous contact of the solvent with the gel. The temperature during the immersion is not particularly limited, but may be, for example, 20 to 70 ° C, 25 to 65 ° C, or 30 to 60 ° C. When heating is carried out, the solvent replacement proceeds rapidly and the amount of solvent required for the replacement is small, but the solvent replacement may be carried out easily at room temperature. In addition, for example, when the solvent replacement step is performed in a plurality of solvent replacement steps, each of the plurality of solvent replacement steps may be performed as described above.

When the solvent replacement step is performed in a plurality of solvent replacement steps, and the later step is less hydrophilic than the earlier step, the other solvent (substitution solvent) is used. Is not particularly limited. In the last solvent replacement step, the other solvent (replacement solvent) is preferably a void layer-producing solvent. Examples of the solvent for producing the void layer include a solvent having a boiling point of 140 ° C. or lower. Examples of the solvent for producing the void layer include alcohols, ethers, ketones, ester solvents, aliphatic hydrocarbon solvents, aromatic solvents and the like. Specific examples of the alcohol having a boiling point of 140 ° C. or lower include isopropyl alcohol (IPA), ethanol, methanol, n-butanol, 2-butanol, isobutyl alcohol (IBA), 1-pentanol, 2-pentanol and the like. Be done. Specific examples of the ether having a boiling point of 140 ° C. or lower include propylene glycol monomethyl ether (PGME), methyl cellosolve, ethyl cellosolve and the like. Boiling point 14
Specific examples of the ketone at 0 ° C. or lower include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone and the like. Specific examples of the ester solvent having a boiling point of 140 ° C. or lower include ethyl acetate, butyl acetate, isopropyl acetate, and normal propyl acetate. Specific examples of the aliphatic hydrocarbon solvent having a boiling point of 140 ° C. or lower include, for example,
Hexane, cyclohexane, heptane, octane and the like can be mentioned. Specific examples of the aromatic solvent having a boiling point of 140 ° C. or lower include toluene, benzene, xylene, anisole and the like. From the viewpoint of being less likely to erode the base material (for example, the resin film) during coating, the solvent for producing the void layer is preferably an alcohol, an ether, or an aliphatic hydrocarbon solvent. The pulverizing solvent may be, for example, one kind or a combination of two or more kinds. In particular, isopropyl alcohol (IPA), ethanol, n-butanol, 2-butanol, isobutyl alcohol (IBA), pentyl alcohol, propylene glycol monomethyl ether (PGME), methyl cellosolve, heptane, and octane have low volatility at room temperature. It is preferable from the aspect. In particular, in order to suppress the scattering of particles (for example, silica compounds) that are the material of the gel, it is preferable that the saturated vapor pressure of the solvent for producing the void layer is not too high (the volatility is not too high). As such a solvent, for example, a solvent having an aliphatic group having 3 or 4 carbon atoms is preferable, and a solvent having an aliphatic group having 4 or more carbon atoms is more preferable. The solvent having an aliphatic group having 3 or 4 or more carbon atoms may be, for example, alcohol. Specific examples of such a solvent include isopropyl alcohol (IPA), isobutyl alcohol (IBA), n-butanol, 2-butanol, 1-pentanol, and the like.
2-Pentanol is preferable, and isobutyl alcohol (IBA) is particularly preferable.

The other solvent (substitution solvent) other than the last solvent substitution step to be performed is not particularly limited, and examples thereof include alcohol, ether, and ketone. Specific examples of the alcohol include, for example, isopropyl alcohol (IPA), ethanol, methanol, n-.
Examples thereof include butanol, 2-butanol, isobutyl alcohol (IBA), pentyl alcohol and the like. Specific examples of ethers include propylene glycol monomethyl ether (PGME), methyl cellosolve, ethyl cellosolve and the like. Specific examples of the ketone include acetone and the like. The other solvent (replacement solvent) only needs to be able to replace the gel-producing solvent or the other solvent (replacement solvent) in the preceding step. Further, the other solvent (solvent for substitution) other than the solvent substitution step which is finally performed.
Is preferably a solvent that does not finally remain in the gel, or even if it remains, does not easily corrode the base material (eg, resin film) during coating. From the viewpoint that the base material (for example, the resin film) is less likely to be corroded during coating, the other solvent (replacement solvent) other than the last solvent replacement step is preferably alcohol. Thus, in at least one of the plurality of solvent replacement steps, the other solvent is preferably alcohol.

In the first solvent replacement step, the other solvent may be, for example, water or a mixed solvent containing water in an arbitrary ratio. Water or a mixed solvent containing water has high compatibility with a highly hydrophilic gel-producing solvent (for example, DMSO), so that the gel-producing solvent can be easily replaced, and it is also preferable in terms of cost.

The plurality of solvent substitution steps are performed after the step in which the other solvent is water, after that, in the step in which the other solvent is a solvent having an aliphatic group having 3 or less carbon atoms, and after that. And a step in which the other solvent is a solvent having an aliphatic group having 4 or more carbon atoms. Further, at least one of the solvent having an aliphatic group having 3 or less carbon atoms and the solvent having an aliphatic group having 4 or more carbon atoms may be alcohol. The alcohol having an aliphatic group having 3 or less carbon atoms is not particularly limited, and examples thereof include isopropyl alcohol (IPA), ethanol, methanol, n-propyl alcohol and the like. The alcohol having an aliphatic group having 4 or more carbon atoms is not particularly limited, and examples thereof include n-butanol, 2-butanol, isobutyl alcohol (IBA), pentyl alcohol and the like. For example, the solvent having an aliphatic group having 3 or less carbon atoms is isopropyl alcohol, and the solvent having 4 carbon atoms is
The solvent having the above aliphatic group may be isobutyl alcohol.

The present inventors have found that it is very important to pay attention to the residual amount of the solvent for gel production, for example, in order to form a void layer having film strength under a relatively mild condition of 200 ° C. or less. It was This finding is not shown in the prior art including the above-mentioned patent document and non-patent document, and is a finding uniquely found by the present inventors.

As described above, the reason (mechanism) that the void layer having a low refractive index can be produced by reducing the residual amount of the gel-producing solvent in the gel is unknown, but it is presumed as follows, for example. That is, as described above, the gel-producing solvent is a high-boiling solvent (eg DM
SO and the like) are preferred. Then, when the sol liquid produced from the gel is applied and dried to produce the void layer, a normal drying temperature and a drying time (not particularly limited, for example, 100 ° C.).
1 minute), it is difficult to completely remove the high boiling point solvent. This is because if the drying temperature is too high or the drying time is too long, problems such as deterioration of the base material may occur.
Then, the high boiling point solvent remaining at the time of coating and drying enters between the crushed products of the gel, slides the crushed products, and the crushed products are densely deposited, and the porosity decreases. Therefore, it is presumed that the low refractive index is unlikely to be exhibited. That is, conversely, if the residual amount of the high boiling point solvent is reduced, such a phenomenon can be suppressed and a low refractive index can be exhibited. However, these are examples of the mechanism that is supposed and do not limit the present invention.

In the present invention, the “solvent” (eg, a solvent for gel production, a solvent for void layer production, a solvent for substitution, etc.) does not have to dissolve the gel or a pulverized product thereof, and for example, the gel or the gel thereof. The pulverized product may be dispersed or precipitated in the solvent.

  As described above, the gel-producing solvent may have a boiling point of 140 ° C. or higher, for example.

The solvent for gel production is, for example, a water-soluble solvent. In the present invention, the "water-soluble solvent" refers to a solvent that can be mixed with water at an arbitrary ratio.

When the solvent replacement step is performed in a plurality of solvent replacement steps, the method is not particularly limited, but each solvent replacement step can be performed as follows, for example. That is, first, the gel is immersed in or brought into contact with the other solvent, and the catalyst for gel production in the gel, the alcohol component produced by the condensation reaction, water and the like are dissolved in the other solvent. After that, the solvent in which the gel has been dipped or contacted is discarded, and the gel is dipped or contacted again with a new solvent. This is repeated until the residual amount of the gel-producing solvent in the gel reaches a desired amount. The immersion time per time is, for example, 0.5 hours or more, 1 hour or more, or 1.5 hours or more, and the upper limit value is not particularly limited, but is 10 hours or less, for example. Further, the immersion of the solvent may be carried out by continuous contact of the solvent with the gel. The temperature during the immersion is not particularly limited, but is, for example, 20 to 70 ° C, 25 to 65 ° C, or 30 to 60 ° C.
May be When heating is carried out, the solvent replacement proceeds rapidly and the amount of solvent required for the replacement is small, but the solvent replacement may be carried out easily at room temperature. This solvent replacement step is performed a plurality of times by gradually changing the other solvent (substitution solvent) from a solvent having a high hydrophilicity to a solvent having a low hydrophilicity (high hydrophobicity). In order to remove the highly hydrophilic gel-producing solvent (such as DMSO), it is simple and efficient to use water as the displacing solvent first, as described above. Then, after removing DMSO and the like with water, the water in the gel is replaced, for example, in the order of isopropyl alcohol ⇒ isobutyl alcohol (coating solvent). That is, since water and isobutyl alcohol have low compatibility, it is possible to efficiently perform the solvent replacement by once replacing with isopropyl alcohol and then replacing with isobutyl alcohol as a coating solvent. However, this is an example, and as described above, the other solvent (substitution solvent) is not particularly limited.

In the present invention, the method for producing a gel is, for example, as described above, in the solvent substitution step, the other solvent (replacement solvent) is gradually changed from a highly hydrophilic solvent to a low hydrophilicity (high hydrophobicity). ) The solvent may be changed to multiple times. According to this, as described above, the residual amount of the solvent for gel production in the gel can be made extremely low. Not only that, for example, it is possible to reduce the amount of the solvent used and to reduce the cost compared with the case where the solvent substitution is performed in one step using only the coating solvent.

Then, after the solvent replacement step, a gel crushing step of crushing the gel in the crushing solvent is performed. Further, for example, as described above, after the solvent replacement step, prior to the gel crushing step, the gel concentration may be measured, if necessary, and then the gel concentration adjusting step may be performed, if necessary. good. The gel concentration measurement after the solvent replacement step and before the gel crushing step can be performed, for example, as follows. That is, first, after the solvent replacement step, the gel is taken out from the other solvent (solvent for grinding). For example, the gel is controlled to have an appropriate shape and size (for example, a block) by the gel morphology control step. Next, after removing the solvent adhering to the periphery of the gel mass, the solid content concentration in one gel mass is measured by the weight drying method. At this time, in order to obtain reproducibility of measured values,
A plurality of (for example, six) chunks taken out at random are used to calculate the average value and the variation of the values. In the concentration adjusting step, for example, the gel concentration of the gel-containing liquid may be reduced by further adding the other solvent (grinding solvent). In the concentration adjusting step, conversely, the gel concentration of the gel-containing liquid may be increased by evaporating the other solvent (grinding solvent).

In the method for producing a gel pulverized product-containing liquid of the present invention, as described above, the gel pulverizing step may be performed in one step, but it is preferable to perform it in a plurality of pulverizing steps. Specifically, for example, the first crushing step and the second crushing step may be performed. In addition, the gel crushing step may further include a gel crushing step in addition to the first crushing step and the second crushing step. That is, in the manufacturing method of the present invention, the gel crushing step is not limited to only two crushing steps, and may include three or more crushing steps.

As described above, a liquid (for example, a suspension) containing the fine pore particles (pulverized product of gel compound) can be prepared. Furthermore, after the liquid containing the fine pore particles is produced, or during the production process, a catalyst that chemically bonds the fine pore particles to each other is added to produce a liquid containing the fine pore particles and the catalyst. can do. The amount of the catalyst added is
Although not particularly limited, it is, for example, 0.01 with respect to the weight of the pulverized product of the gel silicon compound.
-20% by weight, 0.05-10% by weight, or 0.1-5% by weight. The catalyst may be, for example, a catalyst that promotes cross-linking between the micropore particles. It is preferable to use a dehydration condensation reaction of residual silanol groups contained in silica sol molecules as the chemical reaction for chemically bonding the fine pore particles. By promoting the reaction between the hydroxyl groups of the silanol groups with the catalyst, continuous film formation in which the void structure is cured in a short time is possible. Examples of the catalyst include a photoactive catalyst and a heat activated catalyst. According to the photoactive catalyst,
For example, in the void layer forming step, it is possible to chemically bond (for example, crosslink) the fine pore particles to each other without heating. According to this, for example, in the void layer forming step, shrinkage of the entire void layer does not easily occur, so that a higher void ratio can be maintained.
In addition to or in place of the catalyst, a substance that generates a catalyst (catalyst generator) may be used. For example, in addition to or in place of the photoactive catalyst, a substance that generates a catalyst by light (photocatalyst generating agent) may be used, or in addition to or in place of the heat activated catalyst, the catalyst may be heated. You may use the substance (thermal catalyst generator) which generate | occur | produces. The photocatalyst generator is not particularly limited, and examples thereof include a photobase generator (a substance that generates a basic catalyst by light irradiation) and a photoacid generator (a substance that generates an acid catalyst by light irradiation). , Photobase generators are preferred. Examples of the photobase generator include 9-anthrylmethyl N, N-diethylcarbamate, trade name WPBG-01.
8), (E) -1- [3- (2-hydroxyphenyl) -2-propenoyl] piperidine ((E) -1- [3- (2-hydroxyphenyl) -2-propenoyl] piperidine, trade name WPBG- 027),
1- (anthraquinone-2-yl) ethyl imidazole carboxylate (1- (anthraq
uinon-2-yl) ethyl imidazolecarboxylate, trade name WPBG-140), 2-nitrophenylmethyl 4-methacryloyloxypiperidine-1-carboxylate (trade name WP)
BG-165), 1,2-diisopropyl-3- [bis (dimethylamino) methylene] guanidinium 2- (3-benzoylphenyl) propionate (trade name WPBG-266).
), 1,2-dicyclohexyl-4,4,5,5-tetramethylbiguanidinium n-butyltriphenylborate (trade name WPBG-300), and 2- (9-oxoxanthene-
2-yl) 1,5,7-triazabicyclo [4.4.0] deca-5-ene (Tokyo Chemical Industry Co., Ltd.), a compound containing 4-piperidinemethanol (trade name HDPD-PB100: manufactured by Heraeus) ) And the like. All the product names including "WPBG" are product names of Wako Pure Chemical Industries, Ltd. Examples of the photoacid generator include aromatic sulfonium salts (trade name SP-170:
ADEKA), triarylsulfonium salts (trade name CPI101A: San Apro), aromatic iodonium salts (trade name Irgacure250: Ciba Japan), and the like. Further, the catalyst that chemically bonds the fine pore particles to each other is not limited to the photoactive catalyst and the photocatalyst generating agent, and may be, for example, a heat active catalyst or a heat catalyst generating agent. Examples of the catalyst that chemically bonds the fine pore particles to each other include basic catalysts such as potassium hydroxide, sodium hydroxide and ammonium hydroxide, and acid catalysts such as hydrochloric acid, acetic acid and oxalic acid. Of these, base catalysts are preferred. The catalyst or catalyst generator that chemically bonds the fine pore particles to each other is used, for example, by adding it to a sol particle liquid (eg suspension) containing the pulverized product (fine pore particles) immediately before coating. Alternatively, it can be used as a mixed liquid in which the catalyst or the catalyst generator is mixed with a solvent. The mixed liquid is, for example, a coating liquid directly added to the sol particle liquid and dissolved, a solution in which the catalyst or catalyst generator is dissolved in a solvent, or a dispersion liquid in which the catalyst or catalyst generator is dispersed in a solvent. But it's okay. The solvent is not particularly limited, and examples thereof include water and buffer solutions.

Further, for example, further, after producing a liquid containing the fine pore particles, by adding a small amount of a high boiling point solvent to the fine pore particle-containing liquid, it is possible to improve the film appearance during film formation by coating. It will be possible. The amount of the high-boiling solvent is not particularly limited, but is, for example, 0.05 to 0.8 times, 0.1 to 0.5 times, and particularly 0.1 to the solid content of the fine pore particle-containing liquid. 15
Double to 0.4 times the amount. The high boiling point solvent is not particularly limited, but for example, dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methylpyrrolidone (NMP), γ- Butyl lactone (GBL)
, Ethylene glycol ethyl ether (EGEE) and the like. Especially boiling point 110
A solvent having a temperature of not lower than 0 ° C. is preferable and not limited to the above specific examples. It is considered that the high boiling point solvent acts as a leveling agent instead of forming a film in which particles are formed side by side. It is preferable to use the high boiling point solvent also in the gel synthesis. However, although it is not clear in detail to add the high boiling point solvent again after completely preparing the solution containing the fine pore particles after completely removing the solvent used in the synthesis, it is easy to work efficiently. However, these mechanisms are examples and do not limit the present invention.

Then, nanoparticles which are surface-modified with the compound having the above-mentioned surface orientation can be added to the produced gel pulverized product-containing liquid, and this can be used for producing the void layer of the present invention. At this time, for example, as described above, the nanoparticles are, for example, 10 to 50% by mass, 15 to 40% by mass, or 20 to 30% by mass with respect to the skeleton component of the void layer. Just add it.

[4-3. Method for producing void layer, laminate, and adhesive layer]
Hereinafter, the method for producing the laminate of the present invention will be described together with examples together with the method for producing the void layer and the method for producing the adhesive layer of the present invention which constitute the laminate. Below, the case where the void layer of the present invention is a silicone porous body formed of a silicon compound will be mainly described. However, the void layer of the present invention is not limited to the silicone porous body. When the void layer of the present invention is other than the silicone porous body, the following description can be applied correspondingly unless otherwise specified. Further, in the following, the pulverized gel-containing liquid used for producing the void layer of the present invention is assumed to include nanoparticles surface-modified with the compound having the above surface orientation, unless otherwise specified. The nanoparticles surface-modified with the compound having the surface orientation can be added to the crushed gel-containing solution after the preparation of the crushed gel-containing solution, for example, as described above.

The method for producing a void layer of the present invention, for example, using the gel pulverized material-containing liquid of the present invention, a precursor forming step of forming a precursor of the void layer, and the gel pulverization contained in the precursor A bonding step of chemically bonding the pulverized products of the substance-containing liquid is included. The precursor can also be referred to as a coating film, for example.

According to the method for producing a void layer of the present invention, for example, a porous structure having the same function as an air layer is formed. The reason is estimated, for example, as follows, but the present invention is not limited to this estimation. Hereinafter, the case where the void layer of the present invention is a silicone porous body will be described as an example.

The gel pulverized product-containing liquid of the present invention used in the method for producing a silicone porous body contains a pulverized product of the silicon compound gel, so that the three-dimensional structure of the gel silica compound is dispersed in a three-dimensional basic structure. It is in the state of being Therefore, in the method for producing a silicone porous body, for example, when the precursor (for example, a coating film) is formed by using the gel pulverized product-containing liquid, the three-dimensional basic structure is deposited and the three-dimensional basic structure is deposited. A structure-based void structure is formed. That is, according to the method for producing a silicone porous body, a new three-dimensional structure formed from the pulverized product having the three-dimensional basic structure, which is different from the three-dimensional structure of the silicon compound gel, is formed. Further, in the method for producing a silicone porous body, the new three-dimensional structure is fixed because the pulverized products are chemically bound to each other. Therefore, although the silicone porous body obtained by the method for producing a silicone porous body has a structure having voids, sufficient strength and flexibility can be maintained. The void layer obtained by the present invention (for example, a silicone porous body) can be used for products in a wide range of fields such as a heat insulating material, a sound absorbing material, an optical member, and an ink image-receiving layer, as a member utilizing the void. Furthermore, a laminated film having various functions can be produced.

Regarding the method for producing the void layer of the present invention, the description of the liquid containing a pulverized gel of the present invention can be applied unless otherwise specified.

In the step of forming the precursor of the porous body, for example, the gel pulverized material-containing liquid of the present invention is applied onto the base material. The gel pulverized product-containing liquid of the present invention can be obtained by, for example, coating the base material, drying the coating film, and then chemically bonding (eg, crosslinking) the pulverized products in the bonding step. It is possible to continuously form a void layer having a film strength of a certain level or higher.

The coating amount of the gel pulverized material-containing liquid on the base material is not particularly limited and can be appropriately set depending on, for example, the desired thickness of the void layer of the present invention. As a specific example, the thickness is 0.1 to 1
When forming the silicone porous body of 000 μm, the coating amount of the gel pulverized product-containing liquid on the substrate is, for example, 0.01 to 6000 of the pulverized product per 1 m ² of the area of the substrate.
It is 0 μg, 0.1 to 5000 μg, and 1 to 50 μg. The preferred coating amount of the pulverized gel-containing liquid is difficult to unambiguously define because it is related to the concentration of the liquid, the coating method, etc., but considering productivity, the coating amount should be as thin as possible. Preferably. When the coating amount is too large, for example, there is a high possibility that the solvent is dried in a drying oven before being volatilized. This allows
Drying of the solvent before the nano-milled sol particles settle and deposit in the solvent to form a void structure may hinder the formation of voids and significantly reduce the void ratio. On the other hand, if the coating amount is too thin, the risk of coating cissing may increase due to irregularities in the base material, variations in hydrophilicity / hydrophobicity, and the like.

After coating the crushed gel-containing liquid on the base material, the precursor of the porous body (coating film) may be subjected to a drying treatment. By the drying treatment, for example, not only is the solvent (solvent contained in the pulverized gel-containing liquid) in the precursor of the porous body removed, but also during the drying treatment, sol particles are precipitated / deposited to form voids. The purpose is to form a structure. The temperature of the drying treatment is, for example, 50 to 250 ° C., 60 to 150 ° C., 70 to 130 ° C., and the time of the drying treatment is, for example, 0.1 to 30 minutes, 0.2 to 10 minutes, 0. 3 to 3 minutes. Regarding the drying treatment temperature and time, it is preferable that the drying treatment temperature and time are shorter and shorter in the context of, for example, continuous productivity and development of high porosity. If the conditions are too strict, for example, in the case where the substrate is a resin film, the glass transition temperature of the substrate is approached, the substrate is stretched in a drying oven, and formed immediately after coating. Defects such as cracks may occur in the void structure. On the other hand, if the conditions are too lenient, for example, since the residual solvent is contained at the timing of exiting the drying oven, when scratched with the roll in the next step, an external defect such as scratches may occur. is there.

The drying treatment may be, for example, natural drying, heat drying, or reduced pressure drying. The drying method is not particularly limited, and for example, a general heating means can be used. Examples of the heating means include a hot air blower, a heating roll, and a far infrared heater. Above all, it is preferable to use heat drying when it is premised on industrial continuous production. As for the solvent used, shrinkage stress is generated due to solvent volatilization during drying, and the resulting void layer (
A solvent having a low surface tension is preferable for the purpose of suppressing the crack phenomenon of the silicone porous body). Examples of the solvent include, but are not limited to, lower alcohols represented by isopropyl alcohol (IPA), hexane, perfluorohexane, and the like.

The base material is not particularly limited, for example, a thermoplastic resin base material, a glass base material, an inorganic substrate represented by silicon, a plastic molded by a thermosetting resin or the like, an element such as a semiconductor, Carbon fiber materials represented by carbon nanotubes can be preferably used, but not limited to these. Examples of the form of the base material include a film and a plate. Examples of the thermoplastic resin include polyethylene terephthalate (PET), acrylic, cellulose acetate propionate (CAP), cycloolefin polymer (COP), triacetate (TAC), polyethylene naphthalate (PEN), polyethylene (PE), polypropylene. (PP) and the like.

In the method for producing a void layer of the present invention, the bonding step is a precursor (coating film) of the porous body.
Is a step of chemically bonding the pulverized products contained in. By the bonding step, for example, the three-dimensional structure of the pulverized material in the precursor of the porous body is fixed. When the conventional immobilization is performed by sintering, for example, high-temperature treatment at 200 ° C. or higher induces dehydration condensation of silanol groups and formation of siloxane bonds. In the bonding step of the present invention, by reacting various additives that catalyze the dehydration condensation reaction, for example, when the base material is a resin film, without causing damage to the base material, the temperature is around 100 ° C. It is possible to continuously form and immobilize the void structure at a relatively low drying temperature of 1, and a short treatment time of less than several minutes.

The method of chemically bonding is not particularly limited and can be appropriately determined depending on, for example, the type of the gel (eg, silicon compound gel). As a specific example, the chemical bond can be performed by, for example, a chemical cross-linking bond between the pulverized products, and in addition, for example,
When inorganic particles such as titanium oxide are added to the pulverized product, it is possible to chemically crosslink the inorganic particles and the pulverized product. Also, when a biocatalyst such as an enzyme is carried, a site other than the catalytically active site may be chemically crosslinked with the pulverized product. Therefore, the present invention can be applied to, for example, an organic-inorganic hybrid void layer, a host-guest void layer, etc., as well as the void layer formed by the sol particles, but is not limited thereto.

The binding step can be performed, for example, by a chemical reaction in the presence of a catalyst, depending on the type of pulverized product of the gel (eg, silicon compound gel). As the chemical reaction in the present invention, it is preferable to utilize a dehydration condensation reaction of residual silanol groups contained in the pulverized product of the silicon compound gel. By promoting the reaction between the hydroxyl groups of the silanol groups with the catalyst, continuous film formation in which the void structure is cured in a short time is possible. Examples of the catalyst include, but are not limited to, base catalysts such as potassium hydroxide, sodium hydroxide and ammonium hydroxide, acid catalysts such as hydrochloric acid, acetic acid and oxalic acid. The catalyst for the dehydration condensation reaction is particularly preferably a base catalyst. Further, a photoacid generating catalyst, a photobase generating catalyst, or the like, which exhibits a catalytic activity when irradiated with light (for example, ultraviolet rays), can be preferably used. The photoacid generating catalyst and the photobase generating catalyst are not particularly limited, but are as described above, for example. The catalyst is
For example, as described above, the sol particle liquid containing the pulverized product is used by adding it just before coating,
Alternatively, it is preferable to use the catalyst as a mixed solution in which the catalyst is mixed. The mixed liquid may be, for example, a coating liquid directly added to the sol particle liquid and dissolved, a solution in which the catalyst is dissolved in a solvent, or a dispersion liquid in which the catalyst is dispersed in a solvent. The solvent is not particularly limited, and examples thereof include water and a buffer solution as described above.

Further, for example, the gel-containing liquid of the present invention may further contain a cross-linking auxiliary agent for indirectly binding the pulverized products of the gel. This cross-linking aid enters between the particles (the pulverized product), and the particles and the cross-linking aid interact with each other or bind to each other, so that it is possible to bind the particles to each other with a distance. It is possible to efficiently increase the strength. As the crosslinking aid, a multi-crosslinked silane monomer is preferable. Specifically, the multi-crosslinked silane monomer may have, for example, an alkoxysilyl group of 2 or more and 3 or less, and the chain length between the alkoxysilyl groups may be 1 or more and 10 or less carbon atoms. May also be included. Examples of the crosslinking aid include bis (trimethoxysilyl) ethane, bis (triethoxysilyl) ethane, bis (trimethoxysilyl) methane, bis (triethoxysilyl) methane, bis (triethoxysilyl) propane, and bis. (Trimethoxysilyl) propane, bis (triethoxysilyl) butane, bis (trimethoxysilyl) butane, bis (triethoxysilyl) pentane, bis (trimethoxysilyl) pentane, bis (triethoxysilyl) hexane, bis (tri) (Methoxysilyl) hexane, bis (trimethoxysilyl) -N-butyl-N-propyl-ethane-1,2-diamine, tris- (3-trimethoxysilylpropyl) isocyanurate, tris- (3-triethoxysilylpropyl ) Examples include isocyanurate. The amount of the crosslinking aid added is not particularly limited, but is, for example, 0.01 to 20% by weight, 0.05 to 15% by weight, or 0.1 to 10% by weight with respect to the weight of the pulverized product of the silicon compound. % By weight.

The chemical reaction in the presence of the catalyst is, for example, light irradiation or heating to the coating film containing the catalyst or the catalyst generator previously added to the gel pulverized product-containing liquid, or the coating film. It can be carried out by spraying the catalyst and then irradiating or heating it, or by spraying the catalyst or catalyst generator while irradiating or heating it. For example, when the catalyst is a photoactive catalyst, the microporous particles can be chemically bonded to each other by light irradiation to form the silicone porous body. When the catalyst is a thermally activated catalyst, the fine porous particles can be chemically bonded to each other by heating to form the silicone porous body. The light irradiation amount (energy) in the light irradiation is not particularly limited, but is, for example, 200 to 800 mJ / cm ² , 250 in terms of @ 360 nm.
~600mJ / cm ^2, or 300~400mJ / cm ^2. From the viewpoint of preventing the effect from being insufficient because the amount of irradiation is not sufficient and the decomposition due to the light absorption of the catalyst generator does not proceed,
An integrated light amount of 200 mJ / cm ² or more is good. Further, from the viewpoint of preventing the base material under the void layer from being damaged and causing heat wrinkles, the integrated light amount of 800 mJ / cm ² or less is preferable.
The wavelength of light in the light irradiation is not particularly limited, but is, for example, 200 to 500 nm, 3
It is 00-450 nm. The irradiation time of light in the light irradiation is not particularly limited, but is, for example, 0.1 to 30 minutes, 0.2 to 10 minutes, or 0.3 to 3 minutes. The conditions of the heat treatment are
There is no particular limitation, and the heating temperature is, for example, 50 to 250 ° C., 60 to 150 ° C., 70 to 1
30 ° C., and the heating time is, for example, 0.1 to 30 minutes, 0.2 to 10 minutes, 0.3 to 3
Minutes. The solvent used is preferably a solvent having a low surface tension for the purpose of suppressing the generation of shrinkage stress due to the volatilization of the solvent during drying and the cracking phenomenon of the void layer due to the shrinkage stress. Examples thereof include, but are not limited to, lower alcohols represented by isopropyl alcohol (IPA), hexane, perfluorohexane, and the like.

As described above, the void layer (for example, a porous silicon body) of the present invention can be manufactured. However, the method for producing the void layer of the present invention is not limited to the above. In addition, the void layer of the present invention, which is a silicone porous body, may be hereinafter referred to as “silicone porous body of the present invention”.

In addition, in the production of the laminate of the present invention, a tacky adhesive layer is further formed on the void layer of the present invention (the tacky adhesive layer forming step). Specifically, for example, the adhesive layer may be formed by applying (coating) a pressure-sensitive adhesive or an adhesive on the void layer of the present invention. Further, by sticking the adhesive layer side, such as a pressure-sensitive adhesive tape having the adhesive layer laminated on a substrate, onto the void layer of the present invention, the adhesive layer is adhered onto the void layer of the present invention. You may form a coating layer. In this case, the base material such as the adhesive tape may be stuck as it is or may be peeled from the adhesive layer. In particular, as described above, by peeling the base material to obtain a void-layer-containing adhesive sheet that does not have a base material (base material-less), the thickness can be significantly reduced, and the thickness of the device, etc. The increase can be suppressed. In the present invention, the “adhesive” and the “adhesive layer” refer to, for example, an agent or layer on the assumption that the adherend is re-peeled. In the present invention, “adhesive” and “adhesive layer” are
For example, it refers to an agent or layer that is not premised on the re-peel of an adherend. However, in the present invention, "
"Adhesive" and "adhesive" are not always clearly distinguishable, and "adhesive layer" and "adhesive layer" are not always clearly distinguishable. In the present invention, the pressure-sensitive adhesive or adhesive forming the tacky-adhesive layer is not particularly limited, and for example, a general pressure-sensitive adhesive or adhesive can be used. Examples of the pressure-sensitive adhesives or adhesives include acrylic-based, vinyl alcohol-based, silicone-based, polyester-based, polyurethane-based, polyether-based, etc. polymer adhesives and rubber-based adhesives. Further, an adhesive and the like composed of a water-soluble crosslinking agent of a vinyl alcohol-based polymer such as glutaraldehyde, melamine and oxalic acid can also be mentioned. Examples of the pressure-sensitive adhesive include the pressure-sensitive adhesive described above. These adhesives and adhesives are
Only one kind may be used, or a plurality of kinds may be used together (for example, mixed, laminated, etc.). As described above, the adhesive layer can protect the void layer from physical damage (especially scratches). The pressure-sensitive adhesive layer preferably has excellent pressure resistance so that the void layer does not collapse even as a void-layer-containing pressure-sensitive adhesive sheet having no base material (base material-less), but particularly preferably Not limited. The thickness of the adhesive / adhesive layer is not particularly limited, but is, for example, 0.1 to 10
0 μm, 5 to 50 μm, 10 to 30 μm, or 12 to 25 μm.

The void layer of the present invention thus obtained may be, for example, further laminated with another film (layer) to form a laminated structure containing the porous structure. In this case, in the laminated structure, the respective constituent elements may be laminated, for example, via the adhesive layer (adhesive or adhesive).

The above-mentioned respective components may be laminated by, for example, continuous treatment using a long film (so-called Roll to Roll or the like) because of its efficiency, and when the base material is a molded product, element or the like. May be subjected to batch processing and laminated.

Hereinafter, a method for forming the laminate of the present invention on a substrate (resin film) will be described with reference to FIGS. FIG. 2 shows a step of laminating and winding a protective film after forming the void layer (silicone porous body), but when laminating on another functional film, the above method is used. Alternatively, it is also possible to apply another functional film and then dry it, and then bond the above-mentioned film-formed void layer immediately before winding. The illustrated film forming method is merely an example, and the present invention is not limited thereto.

The base material may be the resin film described above. In this case, the void layer of the present invention is obtained by forming the void layer on the substrate. The void layer of the present invention can also be obtained by forming the void layer on the substrate and then laminating the void layer on the resin film described in the description of the void layer of the present invention.

In the cross-sectional view of FIG. 1, an example of steps in the method for producing a laminate of the present invention in which the void layer, the intermediate layer, and the adhesive layer are laminated on the base material (resin film) in the above order, It shows typically. In FIG. 1, the method for forming the void layer is a coating step in which a sol particle liquid 20 ″ of a pulverized product of the gel compound is coated on a substrate (resin film) 10 to form a coating film. (1)
A drying step (2) of drying the sol particle liquid 20 ″ to form a dried coating film 20 ′,
And, a chemical treatment step (for example, a crosslinking step) of forming the void layer 20 by chemically treating the coating film 20 ′ (for example, a crosslinking treatment) (3), and the adhesive layer 30 on the void layer 20. Adhesive layer coating step of applying (adhesive layer forming step) (4) and intermediate layer forming step (5) of reacting the void layer 20 with the adhesive layer 30 to form the intermediate layer 22. including. The chemical treatment step (crosslinking step) (3) corresponds to the "void layer forming step" in the method for producing a laminated film of the present invention. In the figure, the intermediate layer forming step (5) (hereinafter sometimes referred to as “aging step”) is a step of improving the strength of the void layer 20 (a crosslinking reaction step of causing a crosslinking reaction inside the void layer 20). ), And after the intermediate layer forming step (5), the void layer 20 is changed to the void layer 21 having improved strength. However, the present invention is not limited to this, and for example, the void layer 20 may not be changed after the intermediate layer forming step (5). In addition, the adhesive layer forming step,
As described above, the application of the tacky-adhesive layer is not limited, and sticking of an adhesive tape having the tacky-adhesive layer or the like may be performed. Through the above steps (1) to (5), as shown in the drawing, on the resin film 10,
It is possible to manufacture a laminated film in which the void layer 21, the intermediate layer 22, and the adhesive layer 30 are laminated in the above order. However, the intermediate layer forming step (5) is not necessary, and the manufactured laminate of the present invention may not include the intermediate layer. Furthermore, the manufacturing method of the laminated film of this invention is the said process (1)-(.
The process other than 5) may or may not be included as appropriate.

In the coating step (1), the coating method of the sol particle liquid 20 ″ is not particularly limited, and a general coating method can be adopted. Examples of the coating method include slot die method, reverse gravure coating method, micro gravure method (micro gravure coating method), dip method (dip coating method), spin coating method, brush coating method, roll coating method, flexographic printing. Method, wire bar coating method, spray coating method, extrusion coating method, curtain coating method, reverse coating method and the like. Among these, the extrusion coating method, the curtain coating method, the roll coating method, the microgravure coating method and the like are preferable from the viewpoint of productivity, smoothness of the coating film, and the like. The coating amount of the sol particle liquid 20 ″ is not particularly limited, and can be appropriately set, for example, so that the thickness of the void layer 20 is appropriate. The thickness of the void layer 21 is not particularly limited and is as described above, for example.

In the drying step (2), the sol particle liquid 20 ″ is dried (that is, the sol particle liquid 2
The dispersion medium contained in 0 ″ is removed), and a dried coating film (precursor of void layer) 20 ′ is formed. The conditions for the drying treatment are not particularly limited and are as described above.

Furthermore, in the chemical treatment step (3), a coating film 20 containing the catalyst or the catalyst generator (for example, a photoactive catalyst, a photocatalyst generator, a heat active catalyst or a heat catalyst generator) added before coating. 'Is irradiated with light or heated to chemically bond (for example, crosslink) the pulverized products in the coating film 20' to form the void layer 20. Light irradiation or heating conditions in the chemical treatment step (3) are not particularly limited and are as described above.

Further, the conditions of the adhesive / adhesive layer coating step (adhesive / adhesive layer forming step) (4) and the intermediate layer forming step (5) are not particularly limited, and are as described above, for example.

Next, FIG. 2 schematically shows an example of a slot die coating apparatus and a method for forming the void layer using the coating apparatus. Although FIG. 2 is a cross-sectional view, the hatch is omitted for ease of viewing.

As shown in the figure, each step in the method using this apparatus is performed while the base material 10 is conveyed in one direction by rollers. The transport speed is not particularly limited, and for example, 1 to 100 m / min,
It is 3 to 50 m / min and 5 to 30 m / min.

First, the coating roll 10 is fed while the base material 10 is fed from the delivery roller 101 and conveyed.
In 2, the coating step (1) of coating the substrate 10 with the sol particle liquid 20 ″ is performed, and then,
The drying process (2) is performed in the oven zone 110. In the coating apparatus of FIG. 2, the coating process (
After 1), prior to the drying step (2), a preliminary drying step is performed. The pre-drying step can be performed at room temperature without heating. In the drying step (2), the heating means 111 is used. As the heating means 111, as described above, a hot air blower, a heating roll, a far infrared heater, or the like can be appropriately used. Further, for example, the drying step (2) may be divided into a plurality of steps, and the drying temperature may be increased as the subsequent drying step is performed.

After the drying step (2), the chemical treatment step (3) is performed in the chemical treatment zone 120. In the chemical treatment step (3), for example, when the dried coating film 20 'contains a photoactive catalyst, light irradiation is performed by lamps (light irradiation means) 121 arranged above and below the base material 10. Alternatively, for example, when the dried coating film 20 ′ contains a thermally activated catalyst, a hot air blower (heating means) is used instead of the lamp (light irradiation device) 121, and hot air blowers 121 arranged above and below the base material 10 are used. The base material 10 is heated by. This cross-linking treatment causes chemical bonding between the pulverized products in the coating film 20 ', and the void layer 20
Is hardened and strengthened. In this example, the chemical treatment step (3) is performed after the drying step (2), but as described above, at which stage of the production method of the present invention the chemical bond between the pulverized products is caused. Is not particularly limited. For example, as described above, the drying step (2) may also serve as the chemical treatment step (3). Even if the chemical bond occurs in the drying step (2), the chemical treatment step (3) may be further performed to further strengthen the chemical bond between the pulverized products. In addition, in a step prior to the drying step (2) (for example, a preliminary drying step, a coating step (1), a step of preparing a coating liquid (for example, a suspension), etc.), the chemicals of the pulverized substances are chemically Coupling may occur.

After the chemical treatment step (3), the adhesive layer coating means 13 is provided in the adhesive layer coating zone 130a.
1a, a pressure-sensitive adhesive or an adhesive is applied (coated) on the void layer 20, and a tacky-adhesive layer coating step (sticky-adhesive layer forming step) (4) of forming the tacky-adhesive layer 30 is performed. Further, as described above, instead of applying (coating) the adhesive or the adhesive, an adhesive tape or the like having the adhesive layer 30 may be attached (adhered).

Further, an intermediate layer forming step (aging step) (5) is performed in the intermediate layer forming zone (aging zone) 130 to react the void layer 20 and the adhesive layer 30 to form the intermediate layer 22.
Further, as described above, in this step, the void layer 20 undergoes a crosslinking reaction inside, and becomes the void layer 21 having improved strength. The intermediate layer forming step (aging step) (5) is performed, for example, on the base material 10.
The heating may be performed by heating the void layer 20 and the adhesive layer 30 using the hot air blowers (heating means) 131 arranged above and below. The heating temperature, time, etc. are not particularly limited, but are as described above, for example.

Then, after the intermediate body forming step (aging step) (5), the laminate having the void layer 21 formed on the base material 10 is wound by the winding roll 105. In FIG. 2, the void layer 21 of the laminate is protected by being covered with a protective sheet fed from the roll 106. Here, instead of the protective sheet, another layer formed of a long film may be laminated on the void layer 21.

FIG. 3 schematically shows an example of a coating device of a micro gravure method (micro gravure coating method) and a method of forming the void layer using the coating device. Although the figure is a cross-sectional view, the hatch is omitted for ease of viewing.

As shown in the figure, each step in the method using this apparatus is performed while the substrate 10 is being transported in one direction by rollers, as in FIG. The transport speed is not particularly limited, and is, for example, 1 to 1.
00 m / min, 3 to 50 m / min, and 5 to 30 m / min.

First, the coating step (1) of coating the sol particle liquid 20 ″ on the base material 10 is performed while the base material 10 is fed out from the delivery roller 201 and conveyed. The coating of the sol particle liquid 20 ″ is performed by the liquid reservoir 202, the doctor (doctor knife) 203 and the micro gravure 20 as shown in the drawing.
4 is used. Specifically, the sol particle liquid 20 ″ stored in the liquid reservoir 202 is attached to the surface of the micro gravure 204, and further, the substrate 10 is controlled by the micro gravure 204 while controlling the thickness to a predetermined value by the doctor 203. Apply to the surface. The micro gravure 20
4 is an example, and the present invention is not limited to this, and any other coating means may be used.

Next, the drying step (2) is performed. Specifically, as shown in the drawing, the substrate 10 coated with the sol particle liquid 20 ″ is conveyed into the oven zone 210, and heated by the heating means 211 in the oven zone 210 to heat the sol particle liquid 20 ′. 'Dry. The heating means 211 is, for example,
It may be the same as in FIG. Further, for example, the drying step (2) may be divided into a plurality of steps by dividing the oven zone 210 into a plurality of sections, and the drying temperature may be increased as the subsequent drying step is performed. After the drying step (2), the chemical processing step (3) is performed in the chemical processing zone 220. In the chemical treatment step (3), for example, when the dried coating film 20 ′ contains a photoactive catalyst, light is irradiated by lamps (light irradiation means) 221 arranged above and below the base material 10. Alternatively, for example, when the dried coating film 20 ′ contains a heat-activated catalyst, a hot air blower (heating means) is used instead of the lamp (light irradiation device) 221, and hot air blowers (upper and lower) arranged above and below the substrate 10 ( (Heating means) 221
The base material 10 is heated. By this cross-linking treatment, the crushed substances in the coating film 20 ′ are chemically bonded to each other, and the void layer 20 is formed.

After the chemical treatment step (3), the adhesive / adhesive layer coating means 23 is provided in the adhesive / adhesive layer coating zone 230a.
1a, a pressure-sensitive adhesive or an adhesive is applied (coated) on the void layer 20, and a tacky-adhesive layer coating step (sticky-adhesive layer forming step) (4) of forming the tacky-adhesive layer 30 is performed. Further, as described above, instead of applying (coating) the adhesive or the adhesive, an adhesive tape or the like having the adhesive layer 30 may be attached (adhered).

Further, an intermediate layer forming step (aging step) (5) is performed in the intermediate layer forming zone (aging zone) 230 to react the void layer 20 and the adhesive layer 30 to form the intermediate layer 22.
Further, as described above, in this step, the void layer 20 becomes the void layer 21 having improved strength. The intermediate layer forming step (aging step) (5) is performed by, for example, hot air blowers arranged above and below the base material 10 (
The heating may be performed by heating the void layer 20 and the adhesive layer 30 using a heating means 231. The heating temperature, time, etc. are not particularly limited, but are as described above, for example.

Then, after the intermediate body forming step (aging step) (5), the laminated film having the void layer 21 formed on the base material 10 is wound by the winding roll 251. Then, for example, another layer may be laminated on the laminated film. Further, before the laminated film is wound by the winding roll 251, another layer may be laminated on the laminated film, for example.

Next, examples of the present invention will be described. However, the present invention is not limited to the following examples.

In the following Reference Examples, Examples and Comparative Examples, the number of parts of each substance (relative amount used)
Is parts by weight (parts by weight) unless otherwise specified.

[Reference Example 1: Production of coating liquid for forming void layer]
First, gelation of a silicon compound (following step (1)) and aging step (following step (2)) were carried out to produce a gel having a porous structure (silicone porous body). After that, the following (3) morphology control step, (4) solvent replacement step, and (5) gel crushing step were performed to obtain a coating liquid for forming a void layer (gel crushed material-containing liquid). In this reference example, the following (
3) The morphology control process was performed as a process different from the following process (1). However, the present invention
The present invention is not limited to this, and for example, the following (3) morphology control step may be performed during the following step (1).

(1) Gelation of Silicon Compound In 22 kg of DMSO, 9.5 kg of a precursor of a silicon compound, MTMS, was dissolved. 5 kg of 0.01 mol / L oxalic acid aqueous solution was added to the mixed solution, and MTMS was hydrolyzed by stirring at room temperature for 120 minutes to generate tris (hydroxy) methylsilane.

After adding 3.8 kg of 28% -concentrated ammonia water and 2 kg of pure water to 55 kg of DMSO, the above-mentioned hydrolyzed mixed liquid was further added and stirred at room temperature for 60 minutes.
The liquid after stirring for 60 minutes was poured into a stainless container having a length of 30 cm, a width of 30 cm, and a height of 5 cm and allowed to stand at room temperature to gel tris-tris (hydroxy) methylsilane to obtain a gel silicon compound. It was

(2) Aging Step The gel silicon compound obtained by performing the gelation treatment was incubated at 40 ° C. for 20 hours to perform the aging treatment to obtain the rectangular parallelepiped lump gel. Since the amount of DMSO (high boiling point solvent having a boiling point of 130 ° C or higher) used in the raw material was about 83% by weight of the total raw material, this gel contained 50% by weight or more of the high boiling point solvent having a boiling point of 130 ° C or higher. It was clear that he was out. Further, in this gel, the amount of MTMS (monomer that is a constituent unit of the gel) used in the raw material was about 8% by weight of the entire raw material, so that the hydrolysis of the monomer (MTMS) that is a constituent unit of the gel It was revealed that the content of the solvent having a boiling point of less than 130 ° C. (methanol in this case) generated by is not more than 20% by weight.

(3) Morphology control step Water, which is a displacing solvent, was poured onto the gel synthesized in the 30 cm × 30 cm × 5 cm stainless container by the steps (1) and (2). Next, the cutting blade of a cutting jig was slowly inserted into the gel from above in the stainless steel container, so that the gel was 1.5 cm × 2 cm ×
It was cut into a rectangular parallelepiped having a size of 5 cm.

(4) Solvent Replacement Step Next, the solvent replacement step was performed as in the following (4-1) to (4-3).

(4-1) After the “(3) Morphology control step”, the gel silicon compound was immersed in water having a weight eight times that of the gel silicon compound, and the mixture was slowly stirred for 1 h so that only water was convected. After 1 h, the water was replaced with the same amount of water, and the mixture was further stirred for 3 h. After that, the water was exchanged again, and then the mixture was heated at 60 ° C. for 3 hours with slow stirring.

(4-2) After (4-1), water was replaced with isopropyl alcohol having a weight four times that of the gel silicon compound, and the mixture was heated at 60 ° C. for 6 hours with stirring.

(4-3) After (4-2), isopropyl alcohol was replaced with isobutyl alcohol having the same weight, and the mixture was heated at 60 ° C. for 6 hours to replace the solvent contained in the gel silicon compound with isobutyl alcohol. As described above, the gel for producing a void layer of the present invention was produced.

(5) Gel crushing step With respect to the gel (gel-like silicon compound) after the solvent replacement step (4), continuous emulsion dispersion (Milder MDN304 type, manufactured by Taiheiyo Kiko Co., Ltd.) in the first crushing step, second Of high pressure medialess crushing (Starburst HJP-25005 type, manufactured by Sugino Machine Ltd.) in the crushing stage of
Milling was done in stages. In this pulverization treatment, 26.6 kg of isobutyl alcohol was added to and weighed 43.4 kg of the gel containing the solvent-substituted gel silicon compound as a solvent, and the first pulverization step was circulation pulverization for 20 minutes. In the second pulverization step, pulverization was performed at a pulverization pressure of 100 MPa. Thus, an isobutyl alcohol dispersion liquid (a liquid containing a pulverized gel) in which nanometer-sized particles (the pulverized product of the gel) were dispersed was obtained. Furthermore, 224 g of a 1.5% concentration solution of WPBG-266 (trade name, manufactured by Wako) in methyl isobutyl ketone was added to 3 kg of the liquid containing the crushed gel, and bis (trimethoxylyl) ethane (manufactured by TCI) in methyl was added. After adding 67.2 g of a 5% isobutyl ketone solution, N, N-dimethylformamide was added to 3%.
1.8 g was added and mixed to obtain a coating liquid.

As described above, the coating liquid for forming the void layer of the present reference example (reference example 1) (the liquid containing the crushed gel)
Was manufactured. Further, the peak pore diameter of the pulverized gel (fine pore particles) in the coating liquid for forming a void layer (liquid containing pulverized gel) was 12 nm when measured by the above-mentioned method.

[Reference Example 2: Modification reaction of nanoparticles with fluoroalkyl group]
0.27 g of IPA (isopropyl alcohol) was added to 0.06 g of a 0.1 N (0.1 mol / L) aqueous HCl solution, and the mixture was stirred to obtain a uniform solution. MIBK-ST (Nissan Chemical's trade name: MIBK [methyl isobutyl ketone] dispersion liquid of Si nanoparticles) was added to the solution in an amount of 10 g, and trimethoxy (1H, 1H, 2H, 2H-nonafluorohexyl) silane was added in an amount of 0. 7 g was added. The mixture thus obtained was heated and stirred at 60 ° C. for 1 h to obtain the Si
The nanoparticle modification reaction is performed to obtain the fluoroalkyl group-modified dispersion liquid of the Si nanoparticles (
A modified nanoparticle dispersion) was obtained.

[Reference Example 3: Formation of tacky adhesive layer]
The adhesive layer of this reference example (reference example 3) was formed by the following procedures (1) to (3).

(1) Preparation of acrylic polymer solution In a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas introducing tube, and a condenser, 90.7 parts of butyl acrylate, 6 parts of N-acryloylmorpholine, and 3 parts of acrylic acid. , 2-hydroxybutyl acrylate, and 0.1 part by weight of 2,2′-azobisisobutyronitrile as a polymerization initiator were added together with 100 g of ethyl acetate. Next, while gently stirring the contents in the four-necked flask, nitrogen gas was introduced to replace the nitrogen. Then, the liquid temperature in the four-necked flask was kept at around 55 ° C. to carry out a polymerization reaction for 8 hours to prepare an acrylic polymer solution.

(2) Preparation of acrylic pressure-sensitive adhesive composition An isocyanate cross-linking agent (trade name "Coronate L" manufactured by Nippon Polyurethane Industry Co., Ltd., Tris) was added to 100 parts of the solid content of the acrylic polymer solution obtained in (1) above. 0.2 parts of methylolpropane tolylene diisocyanate adduct), benzoyl peroxide (
Acrylic adhesive blended with 0.3 parts of Nippon Oil & Fats Co., Ltd. product name "Nyper BMT") and 0.2 parts of γ-glycidoxypropylmethoxysilane (Shin-Etsu Chemical Co., Ltd. product name "KBM-403") An agent composition (acrylic adhesive solution) was prepared.

(3) Formation of a tacky adhesive layer A polyethylene terephthalate (PET) film (manufactured by Mitsubishi Kagaku Polyester Film Co., Ltd., thickness: 38) obtained by subjecting the acrylic pressure-sensitive adhesive composition obtained in (2) above to a silicone treatment.
μm) on one side so that the thickness of the adhesive layer after drying is 10 μm,
Drying was performed for minutes to form a pressure-sensitive adhesive layer (adhesive layer). 23 ° C of this adhesive layer (adhesive layer)
The storage elastic modulus G ′ at that time was 1.3 × 10 ⁵ .

[Reference Example 4: Formation of tacky adhesive layer]
The adhesive layer of this reference example (reference example 4) was formed by the following procedures (1) to (3).

(1) Preparation of acrylic polymer solution In a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas introducing tube, and a condenser, 97 parts of butyl acrylate, 3 parts of acrylic acid, 1 part of 2-hydroxyethyl acrylate, And, 0.1 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, 100 g of ethyl acetate
I put it in with. Next, while gently stirring the contents in the four-necked flask, nitrogen gas was introduced to replace the nitrogen. After that, keep the liquid temperature in the four-necked flask at around 55 ° C.
A polymerization reaction was carried out for a time to prepare a solution of an acrylic polymer.

(2) Preparation of acrylic pressure-sensitive adhesive composition An isocyanate cross-linking agent (trade name "Coronate L" manufactured by Nippon Polyurethane Industry Co., Ltd., Tris) was added to 100 parts of the solid content of the acrylic polymer solution obtained in (1) above. 0.5 parts of methylolpropane tolylene diisocyanate adduct), benzoyl peroxide (
Nippon Oil & Fats Co., Ltd. trade name "Nyper BMT") 0.2 parts and γ-glycidoxypropylmethoxysilane (Shin-Etsu Chemical Co., Ltd. trade name "KBM-403") 0.2 parts are mixed. A solution of the acrylic pressure-sensitive adhesive composition was prepared.

(3) Formation of tacky adhesive layer The solution of the acrylic pressure-sensitive adhesive composition obtained in (2) above was treated with a silicone-treated polyethylene terephthalate (PET) film (Mitsubishi Chemical Polyester Film Co., Ltd., thickness: 38 μm). ) Is coated on one side so that the thickness of the pressure-sensitive adhesive layer after drying is 20 μm.
The adhesive layer (adhesive layer) was formed by drying at 3 ° C. for 3 minutes. The storage elastic modulus G ′ of this pressure-sensitive adhesive layer (adhesive layer) at 23 ° C. was 1.1 × 10 ⁵ .

[Reference Example 5: Formation of tacky adhesive layer]
The adhesive layer of this reference example (reference example 5) was formed by the following procedures (1) to (3).

(1) Preparation of acrylic polymer solution In a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas introducing tube, and a condenser, 77 parts of butyl acrylate, 20 parts of phenoxyethyl acrylate, N-vinyl-2-pyrrolidone. Two
Parts, 0.5 parts of acrylic acid, 0.5 parts of 4-hydroxybutyl acrylate, and 0.1 parts of 2,2′-azobisisobutyronitrile as a polymerization initiator were added together with 100 parts of ethyl acetate. Next, while gently stirring the contents in the four-necked flask, nitrogen gas was introduced to replace the nitrogen. Then, the liquid temperature in the four-necked flask was kept at around 55 ° C. to carry out a polymerization reaction for 8 hours to prepare an acrylic polymer solution.

(2) Preparation of acrylic pressure-sensitive adhesive composition An isocyanate cross-linking agent (trade name “TAKENATE D160N” manufactured by Mitsui Chemicals, Inc., Tris) was added to 100 parts of the solid content of the solution of the acrylic polymer obtained in (1) above. 0.1 parts of methylolpropane hexamethylene diisocyanate), 0.3 parts of benzoyl peroxide (trade name “Nyper BMT” manufactured by NOF CORPORATION), γ-glycidoxypropylmethoxysilane (
0.2 part of trade name "KBM-403" manufactured by Shin-Etsu Chemical Co., Ltd. was mixed to prepare a solution of an acrylic pressure-sensitive adhesive composition.

(3) Formation of tacky adhesive layer A solution of the acrylic pressure-sensitive adhesive composition obtained in (2) above is treated with a silicone-based release agent to form a polyethylene terephthalate film (separator film: manufactured by Mitsubishi Chemical Polyester Film Co., Ltd., It was applied to one side of the product name "MRF38") and dried at 150 ° C for 3 minutes to form a pressure-sensitive adhesive layer (adhesive layer) having a thickness of 20 µm on the surface of the separator film.
The storage elastic modulus G ′ of this pressure-sensitive adhesive layer (adhesive layer) at 23 ° C. was 1.1 × 10 ⁵ .

[Reference Example 6: Formation of tacky adhesive layer]
The adhesive layer of this reference example (reference example 6) was formed by the following procedures (1) to (3).

(1) Preparation of Prepolymer Composition Photopolymerization was performed on a monomer mixture composed of 68 parts of 2-ethylhexyl acrylate, 14.5 parts of N-vinyl-2-pyrrolidone, and 17.5 parts of 2-hydroxyethyl acrylate. After blending 0.035 parts of an initiator (trade name "Irgacure 184", BASF Corporation) and 0.035 parts of a photopolymerization initiator (trade name "Irgacure 651", BASF Corporation), the viscosity (BH
Viscometer No. The prepolymer composition was obtained by irradiating with ultraviolet rays until a rotor of 5 rotors, 10 rpm, and a measuring temperature of 30 ° C.) reached about 20 Pa · s to partially polymerize the monomer components.

(2) Preparation of acrylic pressure-sensitive adhesive composition The prepolymer composition obtained in (1) above was mixed with hexanediol diacrylate (HD
DA) 0.150 parts and a silane coupling agent (trade name "KBM-403", Shin-Etsu Chemical Co., Ltd.) 0.3 parts were added and mixed to obtain an acrylic pressure-sensitive adhesive composition.

(3) Formation of a tacky adhesive layer A polyethylene terephthalate (PET) film (manufactured by Mitsubishi Kagaku Polyester Film Co., Ltd., thickness: 50) obtained by subjecting the acrylic pressure-sensitive adhesive composition obtained in (2) above to a silicone treatment.
Polyethylene terephthalate (PET) film (manufactured by Mitsubishi Kagaku Polyester Film Co., Ltd., with a thickness of 25 μm) applied to one side of : 38 μm) was provided to cover the coating layer to block oxygen.
Next, this laminated body was irradiated with ultraviolet light having an illuminance of 5 mW / cm 2 for 300 seconds from the upper surface (MRF38 side) of the laminated body with a black light (manufactured by Toshiba). Further, a drying treatment was performed for 2 minutes with a dryer at 90 ° C. to volatilize the residual monomer to form a pressure-sensitive adhesive layer (adhesive layer). The storage elastic modulus G ′ of this pressure-sensitive adhesive layer (adhesive layer) at 23 ° C. was 1.1 × 10 ⁵ .

[Example 1]
After adding 0.06 g of the modified nanoparticle dispersion liquid obtained in Reference Example 2 to 3 g of the void layer-forming coating liquid prepared in Reference Example 1, coating and drying was further performed on an acrylic base material to obtain a film thickness. A void layer of about 800 nm (porosity 59% by volume) was formed. Next, UV irradiation (300 mJ) from the void layer surface
Was done. Then, the adhesive layer (adhesive) having a thickness of 10 μm obtained in Reference Example 3 was attached to the surface of the void layer to produce a laminate of the void layer and the adhesive layer.

Further, the laminate of this example manufactured as described above was placed in an oven at 85 ° C. and 85% RH, and a heating and humidification durability test was performed for 130 hours. The filling degree of the void portion of the void layer after the heating and humidification durability test was confirmed by SEM, and the residual rate of the void ratio was calculated. The results are shown in Table 1.

[Example 2]
The procedure of Example 1 was repeated except that the pressure-sensitive adhesive of Reference Example 3 was used instead of the pressure-sensitive adhesive of Reference Example 3, to produce a void layer and a laminate of this Example. Further, a heating and humidification durability test was conducted in the same manner as in Example 1 to calculate the residual rate of porosity. The results are shown in Table 1.

[Example 3]
The procedure of Example 1 was repeated, except that the pressure-sensitive adhesive obtained in Reference Example 5 was used instead of the pressure-sensitive adhesive of Reference Example 3, to produce a void layer and a laminate of this example. Further, a heating and humidification durability test was conducted in the same manner as in Example 1 to calculate the residual rate of porosity. The results are shown in Table 1.

[Example 4]
The procedure of Example 1 was repeated, except that the pressure-sensitive adhesive of Reference Example 3 was used instead of the pressure-sensitive adhesive of Reference Example 3, to produce a void layer and a laminate of this Example. Further, a heating and humidification durability test was conducted in the same manner as in Example 1 to calculate the residual rate of porosity. The results are shown in Table 1.

[Comparative Example 1]
Instead of the modified nanoparticle dispersion obtained in Reference Example 2, the same amount of MIBK-ST (trade name of Nissan Chemical: MIBK [methylisobutylketone] dispersion of Si nanoparticles) was modified with a fluoroalkyl group. The same operation as in Example 1 was carried out except that it was used as it was, to produce a void layer and a laminate of this comparative example. Further, a heating and humidification durability test was conducted in the same manner as in Example 1 to calculate the residual rate of porosity. The results are shown in Table 1.

[Comparative example 2]
Instead of the modified nanoparticle dispersion liquid obtained in Reference Example 2, trimethoxy (1H, 1H, 2H,
A void layer and a laminate of this comparative example were produced by performing the same operation as in Example 1 except that only 0.01 g of 2H-nonafluorohexyl) silane was added (no Si nanoparticles were added). .. Further, a heating and humidification durability test was conducted in the same manner as in Example 1 to calculate the residual rate of porosity. The results are shown in Table 1.

In addition, the adhesive strength of each of the laminates of Examples 1 to 4 and Comparative Examples 1 and 2 was measured by the above-described measuring method. The results are also shown in Table 1.

As shown in Table 1, in the laminates using the void layers of Examples 1 to 4, difficulty in permeating the pressure-sensitive adhesive (adhesive adhesive layer) into the voids was realized, and voids after the durability test were realized. The residual rate of voids in the layer was high. On the other hand, Comparative Example 1 in which nanoparticles were used as they were without modification with a fluoroalkyl group,
Also, in Comparative Example 2 in which only 0.01 g of trimethoxy (1H, 1H, 2H, 2H-nonafluorohexyl) silane was added without using nanoparticles, the pressure-sensitive adhesive (adhesive / adhesive layer) is a void space layer. And the residual rate of voids in the void layer after the durability test was low.

In addition, FIG. 4 shows a cross-sectional photograph (cross-sectional SEM image) of the laminated body of Example 1 by a scanning electron microscope (SEM). Further, FIG. 5 shows a cross-sectional photograph (cross-sectional SEM image) of the laminate of Comparative Example 1, and FIG. 6 shows a cross-sectional photograph (cross-sectional SEM image) of the laminate of Comparative Example 2. Section SE of FIGS.
Each of the M images is a sectional SEM image after the durability test. As shown in the photograph in Figure 4,
It was confirmed that in the laminate of Example 1, the void remaining rate of the void layer after the durability test was high. On the other hand, in the laminates of Comparative Examples 1 and 2, as shown in the photographs of FIGS. 5 and 6, the pressure-sensitive adhesive (adhesive layer) penetrated into the voids of the void layer, and the void layer after the durability test was performed. The residual rate of voids was low.

As described above, according to the present invention, it is possible to provide a void layer, a laminate, a method for producing a void layer, an optical member, and an optical device in which a pressure-sensitive adhesive or an adhesive hardly penetrates into the void. The use of the present invention is not particularly limited. For example, the optical device of the present invention is not particularly limited, and examples thereof include an image display device and a lighting device. Examples of the image display device include a liquid crystal display, an organic EL display, and a micro LED display. Examples of the lighting device include organic EL lighting. Furthermore, the use of the void layer and the laminate of the present invention is not limited to the optical member and optical device of the present invention, and can be used in a wide range of applications.

10 Base Material 20 Void Layer 20 ′ Coating Film (After Drying)
20 '' sol particle liquid 21 void layer 22 with improved strength intermediate layer 30 adhesive layer 101 delivery roller 102 coating roll 110 oven zone 111 hot air blower (heating means)
120 Chemical treatment zone 121 Lamp (light irradiation means) or hot air blower (heating means)
130a Adhesive layer coating zone 130 Intermediate forming zone 131a Adhesive layer coating means 131 Hot air blower (heating means)
105 winding roll 106 roll 201 delivery roller 202 liquid reservoir 203 doctor (doctor knife)
204 Microgravure 210 Oven zone 211 Heating means 220 Chemical treatment zone 221 Light irradiation means or heating means 230a Adhesive layer coating zone 230 Intermediate formation zone 231a Adhesive layer coating means 231 Hot air blower (heating means)
251 winding roll

Claims (8)

Includes nanoparticles surface-modified with a compound having surface orientation, and has a porosity of 35% by volume.
The above is the void layer. The compound having the surface orientation is an alkoxysilane derivative,
The void layer according to claim 1, wherein the alkoxysilane derivative contains a fluoroalkyl group having 5 to 17 fluorine atoms. The void layer according to claim 1 or 2, wherein the nanoparticles are contained in an amount of 10 to 50 mass% with respect to a skeleton component of the void layer. A laminate in which the void layer according to any one of claims 1 to 3 and an adhesive layer are directly laminated. A coating step of coating a dispersion containing the nanoparticles,
The manufacturing method of the void | hole layer as described in any one of Claim 1 to 3 including the drying process which dries the applied said dispersion liquid. The manufacturing method according to claim 5, wherein a layer made of the nanoparticles is formed inside the void layer together with the formation of the void layer. An optical member comprising the void layer according to claim 1 or the laminate according to claim 4.   An optical device including the optical member according to claim 7.