TWI783986B - Optical sheet for light guide plate type liquid crystal display, backlight unit for light guide plate type liquid crystal display, and light guide plate type liquid crystal display - Google Patents

Abstract

The present invention provides an optical sheet for a light guide plate type liquid crystal display having a low refractive index layer having an extremely low refractive index. The optical sheet for a light guide plate type liquid crystal display of the present invention is characterized in that: the first optical film (light guide plate), the low refractive index layer and the second optical film (reflection plate) are laminated in the aforementioned order, and the low refractive index layer The refractive index is 1.25 or less.

Description

Optical sheet for light guide plate type liquid crystal display, backlight unit for light guide plate type liquid crystal display, and light guide plate type liquid crystal display

The present invention relates to an optical sheet for a light guide plate type liquid crystal display, a backlight unit for a light guide plate type liquid crystal display, and a light guide plate type liquid crystal display.

Background of the Invention In optical devices such as a light guide plate LCD (Liquid Crystal Display, also known as a liquid crystal display device or a liquid crystal display), for example, an air layer with a low refractive index is used as a total reflection layer. Specifically, for example, each optical film member (such as a light guide plate and a reflection plate) in a liquid crystal device is laminated through air. However, with the thinning trend of devices, the integration of various components is desired. Therefore, a method of integrating components with an adhesive without interposing an air layer is often carried out (for example, Patent Document 1). However, if there is no air layer for total reflection, the incident light at an oblique angle will not be totally reflected and retroreflection cannot be used, which may reduce the utilization efficiency of light.

Therefore, there are literatures that propose 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.

Prior Art Documents Patent Documents Patent Document 1: Japanese Patent Laid-Open No. 2012-156082 Patent Document 2: Japanese Patent Laid-Open No. H10-62626

Outline of the Invention Problems to be Solved by the Invention However, the low-refractive index layer has a much higher refractive index than the air layer, so it cannot fully play the role of replacing the air layer, and the reduction in optical characteristics cannot be avoided.

Therefore, an object of the present invention is to provide an optical sheet for a light guide plate type liquid crystal display, a backlight unit for a light guide plate type liquid crystal display, and a light guide plate type liquid crystal display having a low refractive index layer having an extremely low refractive index. means to solve problems

In order to achieve the aforementioned object, the optical sheet for a light guide plate type liquid crystal display of the present invention is characterized in that: the first optical film, the low refractive index layer and the second optical film are laminated in the aforementioned order, and the refractive index of the aforementioned low refractive index layer is Below 1.25.

The backlight unit for a light guide plate type liquid crystal display of the present invention comprises the aforementioned optical sheet for a light guide plate type liquid crystal display of the present invention, a side light and a light guide plate.

The light guide plate type liquid crystal display of the present invention includes the aforementioned backlight unit for a light guide plate type liquid crystal display of the present invention.

Effects of the Invention According to the present invention, an optical sheet for a light guide plate type liquid crystal display, a backlight unit for a light guide plate type liquid crystal display, and a light guide plate type liquid crystal display having a low refractive index layer having an extremely low refractive index can be provided.

Modes for Carrying Out the Invention Next, the present invention will be described in more detail with examples. However, the present invention is not limited in any way by the following description.

In the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, the first optical film and the second optical film may be a lower polarizing plate, a brightness enhancement film, an embossed sheet, a diffuser plate, a light guide plate or a reflective plate, respectively.

In the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, at least one of the first optical film and the second optical film may be a light guide plate.

In the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, one of the first optical film and the second optical film may be a light guide plate, and the other may be an optical member other than the light guide plate. The optical components other than the aforementioned light guide plate can be, for example, reflective plates, diffuser plates, or lamella sheets or lamina sheets with a diffusing function.

Also, the optical sheet for a light guide plate type liquid crystal display of the present invention may contain, for example, one or more optical films other than the aforementioned first optical film and the aforementioned second optical film.

In the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, at least one of the first optical film and the second optical film may be laminated with the low refractive index layer via an adhesive layer. In addition, below, when the said low-refractive-index layer and the said 1st optical film are laminated|stacked via an adhesive layer, the said adhesive layer may be called a "1st adhesive layer." In addition, below, when the said low-refractive-index layer and the said 2nd optical film are laminated|stacked through an adhesive layer, the said adhesive layer may be called a "2nd adhesive layer."

In the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, the aforementioned low refractive index layer may be a void layer. Also, for example, the aforementioned low refractive index layer may be a void layer having a porosity of 35% by volume or more.

In the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, the thickness of the first adhesive layer and the second adhesive layer relative to the total thickness of the first adhesive layer, the low refractive index layer, and the second adhesive layer The total thickness of the adhesive layer may be, for example, 85% or more, 88% or more, 90% or more, or 92% or more, and may be, for example, 99.9% or less, 99.5% or less, 99.3% or less, or 99.2% or less.

In the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, the light transmittance of the laminate of the first adhesive layer, the low refractive index layer, and the second adhesive layer may be 80% or more. Also, for example, the haze of the laminate of the first adhesive layer, the low refractive index layer, and the second adhesive layer may be 3% or less. The aforementioned light transmittance can be, for example, more than 82%, more than 84%, more than 86%, or more than 88%, and the upper limit is not particularly limited, ideally 100%, for example, it can be less than 95%, less than 92%, less than 91%, or Below 90%. The haze measurement of the said laminate can be performed by the same method as the haze measurement of the low-refractive-index layer mentioned later, for example. In addition, the said light transmittance refers to the light transmittance of wavelength 550nm, and can be measured by the following measuring method, for example.

(Measurement method of light transmittance) Using a spectrophotometer U-4100 (trade name of Hitachi, Ltd.), the state of the adhesive sheet containing the low refractive index layer without the separator (the aforementioned first adhesive layer, A laminate of the aforementioned low refractive index layer and the aforementioned second adhesive layer) was used as a sample to be measured. Next, the total light transmittance (light transmittance) of the above-mentioned sample when the total light transmittance of air was 100% was measured. The value of the aforementioned total light transmittance (light transmittance) is a value measured at a wavelength of 550 nm.

The manufacturing method of the optical sheet for a light guide plate type liquid crystal display of the present invention is not particularly limited, for example, it may be a manufacturing method comprising the following steps: a step of forming a low refractive index layer, forming the aforementioned low refractive index layer on a resin film substrate for transfer printing. index layer; and a transfer printing step, transferring the aforementioned low refractive index layer onto the aforementioned adhesive layer. In addition, below, this manufacturing method may be called "the manufacturing method of the optical sheet for 1st light guide plate type liquid crystal displays." Also, generally, a thinner thing is sometimes called a "film" and a thicker thing is called a "sheet" for distinction, but in the present invention, "film" and "sheet" are not particularly distinguished.

The method for manufacturing an optical sheet for a liquid crystal display in the form of a light guide plate according to the present invention may further include, for example, a step of attaching a separator, which is to attach the aforementioned separate pieces.

The method for producing an optical sheet for a liquid crystal display in the form of a light guide plate according to the present invention may further include, for example, a step of peeling off the resin film substrate for transfer, which is to apply the resin for transfer after the step of attaching the separator. Film substrate peeled off. In this case, the peeling force between the separator and the adhesive layer is preferably greater than the peeling force between the transfer resin film substrate and the low-refractive index layer. For another example, there may be further a step of peeling off the separator and a step of attaching an optical film thereafter. The former is to peel the aforementioned separator from the aforementioned adhesive layer, and the latter is to attach the aforementioned first optical film or the aforementioned second optical film to the The aforementioned adhesive layer. In addition, for example, instead of using the separator, the first optical film or the second optical film may be directly attached to the adhesive layer instead of the separator.

In the first method of manufacturing an optical sheet for a light guide plate type liquid crystal display of the present invention, for example, the resin film substrate for transfer may be formed of an alicyclic structure-containing resin or an aliphatic structure-containing resin. In particular, an alicyclic structure-containing resin excellent in heat resistance is desired from the viewpoint of durability against heating and drying during formation of the low refractive index layer. The aliphatic structure-containing resin is not particularly limited, and examples thereof include polyolefin, polypropylene, polymethylpentene, and the like. The aforementioned alicyclic structure-containing resin is not particularly limited, and examples thereof include polynorbornene, cyclic olefin copolymer, and the like.

In addition, the manufacturing method of the optical sheet for liquid crystal display in the form of a light guide plate of the present invention may also be a manufacturing method including the following steps: coating step, coating the raw material for directly coating the aforementioned low refractive index layer on the aforementioned adhesive layer liquid; and a drying step of drying the aforementioned coating liquid. In addition, below, this manufacturing method may be referred to as "the manufacturing method of the optical sheet for 2nd light guide plate type liquid crystal displays."

In addition, the manufacturing method of the optical sheet for liquid crystal display in the form of a light guide plate of the present invention may also be a manufacturing method comprising the following steps: a coating step, directly coating the aforementioned low-density film on the aforementioned first optical film or the aforementioned second optical film. a coating solution for the raw material of the refractive index layer; and a drying step of drying the aforementioned coating solution. In addition, below, this manufacturing method may be referred to as "the manufacturing method of the optical sheet for 3rd light guide plate type liquid crystal displays." In addition, the manufacturing method of the 1st, 2nd, and 3rd optical sheet for liquid crystal displays of light guide plate type of this invention is collectively referred to as "the manufacturing method of optical sheet for liquid crystal displays of light guide plate type of this invention" below sometimes.

In the light guide plate type liquid crystal display (hereinafter sometimes referred to as "light guide plate type LCD"), for example, there is an LED light guide plate type LCD that uses LED (light emitting diode: light emitting diode) for backlight (side light). For example, in each optical film on the backlight side of the lower plate polarizer of a light guide plate type LCD, each optical film can be laminated with an air layer interposed therebetween. The effect of light reflection. In LCD with LED light guide plate, for example, reflective plate, light guide plate (including LED), diffuser plate, diffuser plate, diffuser plate with diffuser, brightening film (reflective polarizing film), and lower plate polarizer can be laminated sequentially.

However, when the aforementioned air layer exists, for example, the optical properties may be lowered due to the deflection of the optical film accompanying the enlargement of the LCD. In addition, for example, foreign matters may enter the aforementioned air layer, which may lower the yield rate of the light guide plate type LCD during the assembly process. Therefore, in order to solve these problems, it is conceivable to attempt to integrate the optical films without using an air layer and to reduce the number of optical films required for lamination at the assembling step. However, if the integration is performed simply by using adhesives at that time, there may be no air layer for total reflection, and as mentioned above, the incident light at an oblique angle cannot be totally reflected, so retroreflection cannot be used. Moreover, there is a possibility that the utilization efficiency of light may be lowered thereby.

On the other hand, in order to solve the aforementioned problems, it may also be considered to insert a low refractive index layer instead of the air layer. However, as mentioned above, the refractive index of the known low-refractive index layer is much higher than that of the air layer, so it cannot fully play the role of replacing the air layer, and still cannot avoid the reduction of optical properties. On the other hand, in the optical sheet for a light guide plate type liquid crystal display of the present invention, the refractive index of the low refractive index layer is as low as 1.25 or less, so that good optical characteristics can be exhibited.

With the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, an optical film that is closer to the backlight side than the polarizing plate of the lower plate of an LED light guide plate type LCD can be integrated. For another example, using the present invention to integrate the various optical films (such as light guide plate and reflector plate or light guide plate, reflector plate and diffuser plate) of LED light guide plate type LCD can reduce the number of components during the LCD assembly process, so it can Reduce the chance of foreign matter mixing between components and improve assembly yield. For another example, it can eliminate the reduction of optical properties (such as uneven brightness, etc.) caused by the deflection when the optical film (such as a reflector) is installed on the component as the size of the LCD increases.

In addition, if you want to fix the low-refractive index layer on the substrate and use it directly, the total thickness including the low-refractive index layer will increase with the thickness of the substrate. Therefore, when the low-refractive index layer is assembled into a light guide plate type LCD and used , The thickness of the LCD itself in the light guide plate method will also increase. On the other hand, for example, since the optical sheet for light guide plate type liquid crystal displays of this invention does not contain a base material, thickness reduction is possible. Specifically, for example, if the base material is not included, there is almost no increase in thickness other than the thickness of the adhesive layer itself, so that the function of the low-refractive index layer can be introduced into the light guide plate type LCD. However, the present invention is not limited thereto. For example, the optical sheet for a light guide plate type liquid crystal display of the present invention may also include a substrate.

Also as mentioned above, in the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, the low refractive index layer, the first optical film and the second optical film may be laminated via an adhesive layer. In this way, the aforementioned adhesive layer can substantially increase the strength of the aforementioned low refractive index layer and protect it from physical damage. Therefore, the brittleness of the low-refractive index layer can be prevented from becoming a fatal problem. The aforementioned physical damage, specifically, for example, when using a low refractive index layer to integrate the optical films, the strength of the low refractive index layer may be insufficient, and the low refractive index may be caused by the difference in thermal expansion coefficient of each optical film. The case where the layer cannot bear the strain between the optical films. By using the aforementioned adhesive layer, the low refractive index layer can be protected from the influence of the strain between the aforementioned optical films. For another example, the scratch resistance of the aforementioned low-refractive index layer can be supplemented by the aforementioned adhesive layer, thereby protecting the aforementioned low-refractive index layer from being scratched. Furthermore, since the optical sheet for a light guide plate type liquid crystal display of the present invention can be attached to other members through the aforementioned adhesive layer, it is easy to introduce the aforementioned low refractive index layer itself into a light guide plate type LCD. That is, according to the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, it can achieve thinning and physical protection of the low refractive index layer while maintaining the low refractive index layer with a high porosity. While maintaining high transparency, it is easy to introduce the function of having a low refractive index layer into other light guide plate LCDs.

[1. Optical sheet for light guide plate type liquid crystal display, backlight unit for light guide plate type liquid crystal display, and light guide plate type liquid crystal display] Hereinafter, the optical sheet for light guide plate type liquid crystal display of the present invention will be described as examples using FIGS. 1, 2 and 6. materials, a backlight unit for a light guide plate type liquid crystal display, and a configuration of a light guide plate type liquid crystal display. 1, 2, and 6 are cross-sectional views, but hatching is omitted for simplicity of illustration.

First, an example of the configuration of a light guide plate type liquid crystal display (light guide plate type LCD) that does not use a low refractive index layer is shown in a cross-sectional view in FIG. 6 . As shown in the figure, the light guide plate type LCD6000 series units A1~A6 are formed by stacking the layers in the above order. Unit A1 is constituted by reflective plate 1020 . Unit A2 is composed of light guide plate 1010 . The light guide plate 1010 has side light. Unit A3 is composed of diffuser plate 1090 . Unit A4 is formed by lamination of the fringe sheet 1030 and the diffusion sheet (the fringe sheet with diffusion) 1040 in the above order. Unit A5 is composed of brightness enhancement film 1050 . Unit A6 is composed of the lower plate polarizing plate 1060, the adhesive (adhesive layer) 1070 and the liquid crystal panel 1080 by laminating the layers in the aforementioned order. Moreover, air layers are arranged between the units A1 and A2 and between the units A2 and A3, respectively.

1 shows an example of the configuration of a light guide plate type liquid crystal display (light guide plate type LCD) of the present invention. As shown in the figure, this light guide plate type LCD1000 is the same as the light guide plate type LCD6000 of FIG. More specifically, this light guide plate type LCD1000 has the laminated body of the low-refractive-index layer 20 and the adhesive layer 30 between the cells A1 and A2 instead of an air layer. In this laminate, adhesive layers 30 are directly laminated on both sides of the low refractive index layer 20 . The reflection plate 1020 of the unit A1 and the light guide plate 1010 of the unit A2 pass through the adhesive layer 30 and are adhered (adhered) on the low refractive index layer 20 respectively. As described above, the unit A1 and the unit A2 are thus integrated to form the unit A12. Moreover, the refractive index of the low-refractive-index layer 20 is 1.25 or less. Unit A12 corresponds to the optical sheet for a light guide plate type liquid crystal display of the present invention. The light guide plate 1010 and the reflection plate 1020 can be regarded as either one of the aforementioned first optical films, and the other as the aforementioned second optical films. In addition, unit A12 is an optical sheet for a light guide plate type liquid crystal display, and includes a light guide plate 1010, and the light guide plate 1010 has side light as described above. Therefore, unit A12 also corresponds to the backlight unit for light guide plate type liquid crystal displays of this invention.

In the light guide plate LCD 1000 shown in FIG. 1 , the low refractive index layer 20 has an extremely low refractive index of 1.25 or less, which is similar to the refractive index of the air layer, so it can exhibit good optical properties.

In addition, the light guide plate LCD 1000 in FIG. 1 does not have a substrate for fixing the low refractive index layer 20, so the low refractive index layer 20 can be introduced without increasing the thickness from the substrate. This enables thinning of the light guide plate type LCD.

In addition, the light guide plate LCD 1000 in FIG. 1 has an adhesive layer 30 on both sides of the low-refractive index layer 20, so that the low-refractive index layer 20 can be protected from physical damage. Specifically, for example, the low-refractive index layer 20 can be protected from strains caused by differences in thermal expansion coefficients of the light guide plate 1010 and the reflection plate 1020 . Also, during the work of assembling the low-refractive-index layer 20 into the light guide plate type LCD 1000 , the low-refractive-index layer 20 can be protected from scratches.

In addition, the light guide plate LCD 1000 in FIG. 1 has no air layer between the light guide plate 1010 and the reflection plate 1020, so the chance of foreign matter entering between the light guide plate 1010 and the reflection plate 1020 can be reduced, and the assembly yield can be improved.

Also, another example of the configuration of the light guide plate type liquid crystal display (light guide plate type LCD) of the present invention is shown in the cross-sectional view of FIG. 2 . As shown in the figure, this light guide plate type LCD2000 is the same as the light guide plate type LCD1000 of FIG. More specifically, this light guide plate type LCD2000 has the laminated body of the low-refractive-index layer 20 and the adhesive layer 30 between the cells A12 and A3 instead of an air layer. In this laminate, adhesive layers 30 are directly laminated on both sides of the low refractive index layer 20 . The light guide plate 1010 of the unit A12 and the diffuser plate 1090 of the unit A3 pass through the adhesive layer 30 and are adhered (adhered) to the low refractive index layer 20 respectively. As described above, the unit A12 and the unit A3 are thus integrated to form the unit A123. Moreover, the refractive index of the low-refractive-index layer 20 is 1.25 or less. Unit A123 corresponds to the optical sheet for a light guide plate type liquid crystal display of the present invention. The light guide plate 1010 and the diffuser plate 1090 can be regarded as any one of which is the aforementioned first optical film, and the other is the aforementioned second optical film. In addition, similarly to the light guide plate type LCD 1000 in FIG. 1 , the light guide plate 1010 and the reflection plate 1020 can also be regarded as either one of the above-mentioned first optical film, and the other one of the above-mentioned second optical film. In addition, unit A123 is an optical sheet for a light guide plate type liquid crystal display, and includes a light guide plate 1010, and the light guide plate 1010 has side light as described above. Therefore, unit A123 also corresponds to the backlight unit for light guide plate type liquid crystal displays of this invention.

The light guide plate LCD2000 in FIG. 2 uses the light guide plate 1010 and the reflection plate 1020 to pass through the adhesive layer 30 and then (adheres) to the low refractive index layer 20 respectively, so that it can exert the same advantages as the light guide plate LCD1000 in FIG. 1 Effect. In addition, the light guide plate LCD 2000 in FIG. 2 is connected (adhesively) to the low refractive index layer 20 by the light guide plate 1010 and the diffuser plate 1090 through the adhesive layer 30 respectively, so as to further exert the same advantageous effects as above.

[2. Optical sheet for light guide plate type liquid crystal display and its manufacturing method] The manufacturing method of the optical sheet for light guide plate type liquid crystal display of the present invention is not particularly limited, for example, it can be carried out by the following method: the aforementioned method of the present invention Method for producing the first optical sheet for a light guide plate type liquid crystal display, method for producing the aforementioned second optical sheet for a light guide plate type liquid crystal display of the present invention, or the aforementioned third optical sheet for a light guide plate type liquid crystal display of the present invention The production method (the production method of the optical sheet for the light guide plate type liquid crystal display of the present invention). The following example illustrates. In addition, below, the low-refractive-index layer which is a component of the optical sheet for light guide plate type liquid crystal displays of this invention may be called "the low-refractive-index layer of this invention." In addition, the method of manufacturing the low-refractive-index layer of this invention may be called "the manufacturing method of the low-refractive-index layer of this invention."

[2-1. Low-refractive-index layer and its manufacturing method] The low-refractive-index layer of the present invention may be formed of, for example, a silicon compound. In addition, the low-refractive-index layer of the present invention may also be, for example, a low-refractive-index layer formed by chemical bonding between microporous particles. For example, the aforementioned microporous particles may be a ground product of gel.

In the method for producing the low-refractive index layer of the present invention, for example, the gel pulverization step for pulverizing the gel of the porous body may be performed in one stage, but it is preferably divided into a plurality of pulverization stages. The number of the aforementioned pulverization stages is not particularly limited, and may be, for example, two stages, or may be three or more stages.

In the method for producing a low-refractive index layer of the present invention, for example, the plurality of pulverization stages may include a first pulverization stage and a second pulverization stage for pulverizing the gel, and the first pulverization stage is to pulverize the gel The stage of making particles with a volume average particle diameter of 0.5~100μm, the above-mentioned second crushing stage is the stage of further crushing the above-mentioned particles to make particles with a volume average particle diameter of 10~1000nm after the above-mentioned first crushing stage. Also, in this case, the plurality of pulverization stages may or may not include pulverization stages other than the first pulverization stage and the second pulverization stage.

In addition, in the present invention, the shape of "particles" (such as particles of the above-mentioned pulverized gel) is not particularly limited, for example, it may be spherical or non-spherical. In addition, in the present invention, the particles of the pulverized product may be, for example, sol-gel beaded particles, nanoparticles (hollow nano-silicon dioxide/nanosphere particles), nanofibers, and the like.

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

In the present invention, the above-mentioned pulverized gel may also be constituted by a structure having at least one shape such as granular, fibrous, and flat. The above-mentioned granular and planar structural units can be composed of inorganic substances, for example. In addition, the constituent elements of the aforementioned granular constituent units may contain, for example, at least one element selected from the group consisting of Si, Mg, Al, Ti, Zn, and Zr. The granular structures (constituent units) can be solid particles or hollow particles, specifically polysiloxane particles or polysiloxane particles with fine pores, silica hollow nanoparticles or silica hollow particles. Nanospheres etc. The aforementioned fibrous constituent units are, for example, nanofibers with a diameter of nanometers, specifically cellulose nanofibers or alumina nanofibers. Examples of flat plate-shaped constituent units include nanoclay, and specifically, nanometer-sized bentonite (eg, Kunipia F [trade name]) and the like. The aforementioned fibrous constituent units are not particularly limited, for example, they may be at least one fibrous substance selected from the group consisting of the following fibers: carbon nanofibers, cellulose nanofibers, alumina nanofibers, chitin Fiber nanofibers, chitosan nanofibers, polymer nanofibers, glass nanofibers and silica nanofibers.

In the manufacturing method of the low-refractive index layer of the present invention, the above-mentioned gel pulverization step (for example, the aforementioned multiple pulverization stages, such as the aforementioned first pulverization stage and the aforementioned second pulverization stage) can also be carried out in the aforementioned "other solvents". conduct. In addition, details about the aforementioned "other solvents" will be described in detail later.

In addition, in the present invention, "solvent" (such as a solvent for gel production, a solvent for low refractive index layer production, a solvent for replacement, etc.) does not need to dissolve the gel or its pulverized product, for example, the aforementioned gel or The pulverized product thereof is dispersed or precipitated in the aforementioned solvent.

The volume average particle diameter of the gel after the first crushing stage may be, for example, 0.5-100 μm, 1-100 μm, 1-50 μm, 2-20 μm, or 3-10 μm. The volume average particle diameter of the gel after the second pulverization stage may be, for example, 10-1000 nm, 100-500 nm, or 200-300 nm. The above-mentioned volume average particle diameter means the particle size variation of the above-mentioned pulverized material in the liquid containing the above-mentioned gel (gel-containing liquid). The volume average particle diameter can be measured, for example, by 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).

In addition, the shear viscosity of the liquid immediately after the first pulverization stage can be, for example, 50 mPa/s or more, 1000 mPa s or more, 2000 mPa s or 3000 mPa s or more at a shear rate of 1000 1/s, and can be For example, it is 100 Pa·s or less, 50 Pa·s or less, or 10 Pa·s or less. The shear viscosity of the liquid immediately after the second crushing stage may be, for example, 1 mPa·s or more, 2 mPa·s or more, or 3 mPa·s or more, and may be, for example, 1000 mPa·s or less, 100 mPa·s or less, or 50 mPa·s or less . In addition, the measuring method of a shear viscosity is not specifically limited, For example, it can measure using a vibratory viscosity measuring machine (made by Sekonic Co., trade name FEM-1000V) as described in the Example mentioned later.

After the first crushing stage, for example, the shear viscosity of the liquid containing the particles may be 50 mPa·s or more, and the volume average particle diameter of the particles may be 0.5 to 50 μm.

The method for producing the low-refractive index layer of the present invention, for example, preferably includes a concentration adjustment step after the above-mentioned solvent replacement step and before the initial pulverization stage, but it may not be included. The concentration adjustment step is to adjust the concentration of the liquid containing the above-mentioned gel. concentration. When the concentration adjustment step is included, it is not appropriate to adjust the concentration of the gel-containing liquid after the initial pulverization stage, for example.

In the concentration adjusting step, the gel concentration of the liquid containing the porous body gel can be adjusted to, for example, 1% by weight or more, 1.5% by weight or more, 1.8% by weight or more, 2.0% by weight or more, or 2.8% by weight or more, and It can be adjusted to, for example, 5% by weight or less, 4.5% by weight or less, 4.0% by weight or less, 3.8% by weight or less, or 3.4% by weight or less. In the concentration adjusting step, the gel concentration of the liquid containing the gel can be adjusted to, for example, 1 to 5% by weight, 1.5 to 4.0% by weight, 2.0 to 3.8% by weight, or 2.8 to 3.4% by weight. From the viewpoint of ease of handling in the gel crushing step, the aforementioned gel concentration should not be too high in order not to make the viscosity too high. Also, from the viewpoint of use as a coating liquid described later, the aforementioned gel concentration should not be too low in order not to make the viscosity too low. The gel concentration of the liquid containing the gel can be calculated by, for example, measuring the weight of the liquid and the weight of the solid content (gel) after removing the solvent of the liquid, and dividing the measured value of the latter by the measured value of the former.

In addition, in the concentration adjusting step, for example, in order to properly adjust the gel concentration of the liquid containing the gel, the concentration may be decreased by adding a solvent or increased by volatilizing the solvent. Or for example, in the aforementioned concentration adjustment step, if the result of measuring the gel concentration of the liquid containing the aforementioned gel shows that the gel concentration is appropriate, the liquid containing the aforementioned gel can be directly mixed with the liquid without reducing the concentration or increasing the concentration (concentration adjustment). for the next step. Or for example, in the above-mentioned concentration adjustment step, the gel concentration of the liquid containing the above-mentioned gel is clearly known to be appropriate without measurement, and the liquid containing the above-mentioned gel can be directly supplied to the next step.

In the above-mentioned gel pulverization step, from immediately before the first pulverization stage to the moment after the final pulverization stage, the weight % concentration change of the liquid containing the gel may be within ±3%, ±2.8%, for example. Within %, within ±2.6%, within ±2.4%, or within ±2.2%.

In the manufacturing method of the low-refractive index layer of the present invention, it is preferable to further include a gel morphology control step before the solvent replacement step, which is to control the shape and size of the gel. In the aforementioned gel morphology control step, control is preferably performed so that the size of the gel does not become too small. Because, as long as the size of the gel is not too small, a large amount of solvent can be attached around the finely pulverized gel to easily prevent the measured value of the solvent concentration from being lower than the actual concentration. The actual concentration is high or the further measurement variation becomes larger and other problems. Also because before the aforementioned solvent replacement step, as long as the size of the gel is not too large, the solvent replacement efficiency is good. Also, after the aforementioned gel shape control step, it is preferable to control so that the size of each gel is almost uniform. Because, as long as the size of each gel is almost uniform, it is possible to suppress the variation in the particle size of the gel pulverized product and the concentration of the gel between batches (lots) of the liquid containing the gel pulverized product, and obtain extremely uniformity easily. The best liquid containing gel powder.

In the aforementioned gel shape control step, the short axis of the aforementioned gel can be controlled to be, for example, 0.5 cm or more, 0.6 cm or more, 0.7 cm or more, or 0.8 cm or more, and can also be controlled, for example, to be less than 15 cm, less than 13 cm, or less than 10 cm. Or less than 8cm. Also, in the aforementioned gel shape control step, the long axis of the aforementioned gel can be controlled to be, for example, less than 30 cm, less than 30 cm, less than 28 cm, less than 25 cm, or less than 20 cm, and can also be controlled to be, for example, more than 1 cm, more than 2 cm, or 3 cm. Above, above 4cm or above 5cm. In addition, in the present invention, the "short axis" of a solid (three-dimensional body) refers to the length measured at the shortest point at the position where the length of the aforementioned solid can be measured. Furthermore, in the present invention, the "major axis" of a solid (3-dimensional body) refers to the length measured at the point where the length of the solid (three-dimensional body) becomes longest at the position where the length of the aforementioned solid can be measured.

The shape of the above-mentioned gel after the above-mentioned gel shape control step is not particularly limited, for example, it is controlled into a cuboid (also including a cube), a cylinder, a polygonal three-dimensional (such as a triangular prism, a hexagonal prism, etc.), spherical or ellipsoid (such as the shape of a football) and so on. After the aforementioned gel shape control step, it is convenient and ideal to control the shape of the aforementioned gel into a cuboid or almost a cuboid. In the above-mentioned gel shape control step, when the above-mentioned gel is controlled into a cuboid, the short side can be controlled to be, for example, 0.5 cm or more, 0.6 cm or more, 0.7 cm or more, or 0.8 cm or more, and can also be controlled to be, for example, 15 cm or less, Below 13cm, below 10cm or below 8cm. In addition, in the aforementioned gel shape control step, when the aforementioned gel is controlled into a cuboid, the long side can be controlled to be, for example, less than 30 cm, less than 30 cm, less than 28 cm, less than 25 cm, or less than 20 cm, and can also be controlled to be more than 1 cm, for example. , 2cm or more, 3cm or more, 4cm or more or 5cm or more. In addition, in the present invention, the "short side" of a cuboid means the shortest side, and the "long side" means the longest side.

The aforementioned gel morphology control step may be performed, for example, after the aforementioned gel manufacturing step for manufacturing the aforementioned gel, or may be performed during the aforementioned gel manufacturing step (simultaneously with the aforementioned gel manufacturing step). More specifically, it is as follows.

In the aforementioned step of controlling the shape of the gel, for example, the aforementioned gel may be cut while the aforementioned gel is fixed, so as to control the aforementioned stereoscopic shape of the aforementioned gel. In the case of the above-mentioned extremely high brittleness of the gel, when cutting the gel, there is a possibility that the gel may crack unevenly regardless of the cutting direction. Therefore, by fixing the surrounding of the gel, the pressure in the compression direction applied during cutting can be evenly applied to the gel itself, so the gel can be cut uniformly along the cutting direction. For example, the shape of the aforementioned gel before the aforementioned solvent replacement step is almost a cuboid, and in the aforementioned gel shape control step, 5 of the 6 faces of the aforementioned almost rectangular parallelepiped gel surface are in contact with other substances. The gel is fixed by contact, and the gel is cut by inserting a cutting jig from the exposed surface with the other side exposed. The cutting jig is not particularly limited, and examples thereof include a cutter, a wire-like strip-shaped jig, a thin and sharp plate-shaped jig, and the like. In addition, the cutting of the above-mentioned gel can also be performed in the above-mentioned other solvents, for example.

For another example, in the aforementioned gel manufacturing step, the raw material of the aforementioned gel can also be solidified in a template (container) corresponding to the shape and size of the aforementioned three-dimensional, so as to control the aforementioned gel into the aforementioned three-dimensional. In this way, even if the gel is extremely brittle, the gel can be controlled into a predetermined shape and size without cutting the gel, so when cutting the gel, it can prevent the gel from occurring irrespective of the cutting direction. The case of uneven collapse.

In addition, in the method for producing the low-refractive index layer of the present invention, for example, the gel concentration of the liquid containing the gel (gel-containing liquid) may be measured after the first pulverization stage is completed and before the final pulverization stage is completed. , and only the aforementioned liquid having the aforementioned gel concentration within a predetermined numerical range is supplied to the subsequent crushing stage. In addition, when measuring the gel concentration, it must be a uniform liquid. Therefore, after the above-mentioned pulverization stage is completed, it should become a liquid with a certain degree of high viscosity and is not prone to solid-liquid separation. As mentioned above, from the point of view of the ease of handling of the gel-containing liquid, in order not to make the viscosity too high, the gel concentration should not be too high; from the point of view of use as a coating liquid, in order not to make the viscosity becomes too low, the gel concentration should not be too low. For example, from such a point of view, it is also possible to supply only the liquid whose gel concentration is within a predetermined numerical range until the final pulverization stage is completed. The predetermined numerical range of the aforementioned gel concentration is the same as the aforementioned, for example, it may also be more than 2.8% by weight and less than 3.4% by weight, but it is not limited thereto. In addition, the above-mentioned gel concentration measurement (concentration management) can be carried out after the completion of the first pulverization stage and before the completion of the final pulverization stage as described above, but it can also be performed after the aforementioned solvent replacement step and before the aforementioned gel pulverization step. One or both of them after the crushing stage (such as the aforementioned second crushing stage), or simply replace them. Furthermore, after the measurement of the gel concentration, for example, only the liquid having the gel concentration within a predetermined numerical range is supplied to the subsequent pulverization stage, or a liquid containing a gel pulverized product is provided as a finished product. In addition, when the gel concentration measurement is performed after the solvent replacement step and before the gel pulverization step, the concentration adjustment step may be performed thereafter if necessary.

In addition, in the concentration management after the solvent replacement step and before the gel pulverization step, since the amount of solvent adhered to the gel is not stable, there is a possibility that the concentration measurement value may vary greatly from one measurement to another. Therefore, it is preferable to control the shape and size of the gel to be almost uniform by the gel shape control step after the solvent replacement step and before the concentration management before the gel pulverization step. Thereby, the concentration can be measured stably. Also, by this, for example, the gel concentration of the gel-containing liquid can be managed uniformly and with high precision.

In the manufacturing method of the low-refractive index layer of the present invention, at least one of the aforementioned plurality of pulverization stages is preferably different from the other at least one pulverization stage in the pulverization method. The pulverization methods of the aforementioned plurality of pulverization stages may all be different, or may be pulverization stages performed in the same pulverization method. For example, when the aforesaid multiple crushing stages are three stages, it can be carried out in a manner in which all three stages are different (that is, using three crushing methods), or any two crushing stages can be carried out in the same crushing method, and only the other A crushing stage is carried out with different crushing methods. In addition, the pulverization method is not particularly limited, and there are, for example, a cavitation method and a medialess method described later.

In the method for producing a low-refractive index layer of the present invention, the liquid containing the pulverized gel is, for example, a sol solution containing particles obtained by pulverizing the gel (particles of the pulverized product).

In the manufacturing method of the low-refractive index layer of the present invention, the above-mentioned multiple pulverization stages may also include a coarse pulverization stage and a main pulverization stage. Sol particles with a gel network structure.

The manufacturing method of the low-refractive index layer of the present invention, for example, after at least one of the pulverizing stages of the aforementioned multiple stages (for example, at least one of the aforementioned first pulverizing stage and the aforementioned second pulverizing stage), further comprises mixing the aforementioned gel Particles are classified in a classification step.

The method for producing the low-refractive index layer of the present invention includes, for example, a gelation step of gelling the bulky porous body in a solvent to form the aforementioned gel. In this case, for example, in the first pulverization stage (for example, the first pulverization stage) among the pulverization stages described above, the gel gelled in the gelation step is used.

The method for producing the low-refractive index layer of the present invention includes, for example, a curing step of curing the gelled gel in a solvent. In this case, for example, the gel after the aging step is used in the first pulverization stage (for example, the first pulverization stage) among the pulverization stages of the aforementioned plurality of stages.

The manufacturing method of the low-refractive-index layer of the present invention, for example, performs the solvent replacement step after the gelation step, that is, replaces the solvent with another solvent. In this case, for example, in the first pulverization stage (for example, the first pulverization stage) among the pulverization stages described above, the aforementioned gel in the aforementioned other solvent is used.

In at least one of the aforementioned multi-stage crushing stages (for example, at least one of the aforementioned first crushing stage and the aforementioned second crushing stage) in the manufacturing method of the low-refractive index layer of the present invention, for example, in the measurement of the aforementioned liquid While shearing the viscosity, the pulverization of the aforementioned porous body is controlled.

For example, at least one of the above-mentioned multi-stage pulverization stages (such as at least one of the aforementioned first pulverization stage and the aforementioned second pulverization stage) in the manufacturing method of the low refractive index layer of the present invention is carried out by high-pressure medium-free pulverization. ).

In the manufacturing method of the low-refractive-index layer of the present invention, the above-mentioned gel is, for example, a gel of a silicon compound containing at least a trifunctional or less saturated bond functional group.

In addition, hereinafter in the method for producing a low-refractive index layer of the present invention, the gel-containing pulverized product liquid obtained by the step including the aforementioned gel pulverizing step may be referred to as "the gel-containing pulverized product liquid of the present invention." ".

According to the gel pulverized product liquid of the present invention, for example, by forming its coating film, the aforementioned pulverized products in the coating film are chemically bonded to each other to form the aforementioned low-refractive material of the present invention as a functional porous body. rate layer. According to the gel pulverized product-containing liquid of the present invention, for example, the low-refractive index layer of the present invention can be provided to various objects. Therefore, the gel pulverized product-containing liquid of the present invention and its production method are very useful, for example, in the production of the aforementioned low-refractive index layer of the present invention.

The liquid containing the pulverized gel of the present invention has, for example, excellent uniformity, so for example, when the low-refractive index layer of the present invention is applied to applications such as optical components, its appearance is quite good.

The gel-containing pulverized product liquid of the present invention, for example, can also be used to apply (coat) the above-mentioned gel-containing pulverized product liquid on a substrate and further dry it to obtain a layer with a high porosity (low-refractive index layer) ) liquid containing gel powder. In addition, the gel-containing pulverized product liquid of the present invention may be, for example, a gel-containing pulverized product liquid for producing a high-porosity porous body (large thickness or bulk body). The aforementioned batch product can be produced, for example, by performing batch film formation using the aforementioned liquid containing the pulverized gel.

As mentioned above, the low refractive index layer of the present invention can also be a void layer. Hereinafter, when the low refractive index layer of the present invention is a void layer, it may be referred to as "the void layer of the present invention". For example, the void layer of the present invention having a high porosity can be produced by a production method comprising the steps of producing the liquid containing the pulverized gel of the present invention, and applying the liquid containing the pulverized gel to a substrate. A step of forming a coating film, and a step of drying the coating film.

Also, for example, a laminated film roll can also be produced by a production method comprising the following steps: producing the liquid containing the pulverized gel of the present invention; unwinding the roll-shaped aforementioned resin film; coating the unwound aforementioned resin film. Coating the above-mentioned liquid containing the pulverized gel to form a coating film; drying the above-mentioned coating film; and, after the above-mentioned drying step, rolling the laminated film in which the above-mentioned low-refractive index layer of the present invention is formed on the above-mentioned resin film Pick. Hereinafter, this manufacturing method may be referred to as "the manufacturing method of the laminated film coil of the present invention". In addition, the laminated film coil produced by the manufacturing method of the laminated film coil of this invention is sometimes called "the laminated film coil of this invention" below.

[2-2. Gel-containing pulverized product liquid and its production method] The gel-containing pulverized product liquid of the present invention contains, for example, the gel pulverized by the aforementioned gel pulverization step (for example, the aforementioned first pulverization stage and the aforementioned second pulverization stage). Gum powder and other solvents mentioned above.

The method for producing the low-refractive index layer of the present invention, for example, may include a multi-stage gel pulverization step for pulverizing the aforementioned gel (such as a porous body gel), such as the aforementioned first pulverization stage and the aforementioned second pulverization step. stage. Hereinafter, the case where the method for producing a gel-containing pulverized product liquid of the present invention includes the aforementioned first pulverizing step and the aforementioned second pulverizing step will be mainly described by way of example. Hereinafter, the case where the aforementioned gel is a porous body (porous body gel) will be mainly described. However, the present invention is not limited thereto, and the description of the case where the aforementioned gel is a porous body (porous body gel) can also be analogously applied to cases other than the aforementioned gel being a porous body. In addition, the above-mentioned multiple pulverization stages (for example, the aforementioned first pulverization stage and the aforementioned second pulverization stage) in the manufacturing method of the low-refractive index layer of the present invention are sometimes collectively referred to as the "gel pulverization step".

The liquid containing the pulverized gel of the present invention can be used to produce a functional porous body that can exhibit the same function as an air layer (such as low refractivity) as described later. The aforementioned functional porous body may also be the low refractive index layer of the present invention, for example. Specifically, the gel-containing pulverized product liquid obtained by the production method of the present invention contains the pulverized product of the porous body gel, and the three-dimensional structure of the unground porous body gel is destroyed to form a A new three-dimensional structure with different gels in the uncompressed porous body. Therefore, for example, the coating film (precursor of the functional porous body) formed by using the liquid containing the above-mentioned pulverized gel has a new type of pore structure that cannot be obtained by using the layer formed by using the non-pulverized porous gel. (new type of void structure) layer. Thereby, the aforementioned layer can exhibit the same function (for example, the same low refractivity) as that of the air layer. In addition, the liquid containing the gel pulverized product of the present invention can be made, for example, after the pulverized product contains residual silanol groups to form a new three-dimensional structure as the aforementioned coating film (precursor of a functional porous body), and then the pulverized product can be substances chemically bond to each other. Thereby, although the formed functional porous body has a structure having voids, sufficient strength and flexibility can be maintained. Therefore, according to the present invention, a functional porous body can be provided to various objects easily and simply. The gel-containing pulverized product liquid obtained by the production method of the present invention is very useful, for example, in the production of the aforementioned porous structure that can be used as a substitute for an air layer. In addition, the air layer must be stacked between the members with a space provided such as a spacer to form an air layer between the members. However, the functional porous body formed by using the liquid containing the pulverized gel of the present invention can exhibit the same function as the air layer as long as it is placed on the target site. Therefore, as described above, the same function as the air layer can be imparted to various objects more easily and simply than forming the air layer.

The gel pulverized product-containing liquid of the present invention may be, for example, the above-mentioned solution for forming a functional porous body or a solution for forming a low-refractive layer. In the gel pulverized product-containing liquid of the present invention, the aforementioned porous body is its pulverized product.

In the gel pulverized product-containing liquid of the present invention, the volume average particle diameter of the pulverized product (particles of the porous gel) is, for example, in the range of 10 to 1000 nm, or 100 to 500 nm, or 200 to 300 nm. The aforementioned volume average particle diameter represents the particle size variation of the aforementioned pulverized product in the liquid containing the gel pulverized product of the present invention. The above-mentioned volume average particle diameter can be measured, for example, by particle size distribution evaluation devices such as dynamic light scattering method and laser diffraction method, and electron microscopes such as scanning electron microscope (SEM) and transmission electron microscope (TEM). .

In addition, in the gel-containing pulverized product liquid of the present invention, the gel concentration of the aforementioned pulverized product is not particularly limited, for example, 2.5 to 4.5% by weight, or 2.7 to 4.0% by weight, or 2.8 ~3.2% by weight.

In the gel pulverized product-containing liquid of the present invention, the above-mentioned gel (such as a porous gel) is not particularly limited, and examples thereof include silicon compounds and the like.

The aforementioned silicon compound is not particularly limited, and examples include silicon compounds containing at least trifunctional or less saturated bond functional groups. The aforementioned "containing three or less functional groups with saturated bond functional groups" means that the silicon compound has three or less functional groups and these functional groups are in a saturated bonded state with silicon (Si).

The aforementioned silicon compound is, for example, a compound represented by the following formula (2). [chemical formula 1]

In the aforementioned formula (2), for example, X is 2, 3 or 4, R ¹ and R ² are straight-chain alkyl or branched-chain alkyl respectively, R ¹ and R ² can be the same or different, and R ¹ is when X is ² , they may be the same or different from each other, and R2 may be the same or different from each other.

The aforementioned X and R ¹ are, for example, the same as X and R ¹ in the aforementioned formula (1). In addition, the aforementioned R ² can be exemplified by, for example, R ¹ in the formula (1) described later.

Specific examples of the silicon compound represented by the aforementioned 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 the aforementioned formula (2). When R ¹ and R ² are methyl groups, the aforementioned silicon compound is trimethoxy(methyl)silane (hereinafter also referred to as “MTMS”). [chemical formula 2]

In the liquid containing the ground gel of the present invention, the concentration of the ground material of the porous gel in the solvent is not particularly limited, for example, 0.3-50% (v/v), 0.5-30% (v/v ), 1.0~10% (v/v). If the concentration of the aforementioned pulverized matter is too high, for example, the fluidity of the liquid containing the aforementioned gel pulverized matter may be significantly reduced, and condensation and smear marks may occur during coating. On the other hand, if the concentration of the aforementioned pulverized product is too low, not only will it take a considerable amount of time to dry the solvent, but also the residual solvent after drying will increase, so there is a possibility that the porosity will decrease.

The physical properties of the gel pulverized product-containing liquid of the present invention are not particularly limited. The shear viscosity of the liquid containing the ground gelatin, for example, is in the following ranges at a shear rate of 10001/s: 1mPa・s~1Pa・s, 1mPa・s~500mPa・s, 1mPa・s~50mPa・s, 1mPa・s~30mPa・s, 1mPa・s~10mPa・s, 10mPa・s~1Pa・s, 10mPa・s~500mPa・s, 10mPa・s~50mPa・s, 10mPa・s~30mPa・s, 30mPa・s~1Pa・s, 30mPa・s~500mPa・s, 30mPa・s~50mPa・s, 50mPa・s~1Pa・s, 50mPa・s~500mPa・s or 500mPa・s~1Pa・s. If the above-mentioned shear viscosity is too high, for example, smear marks may occur and the transfer rate of gravure coating may decrease and other adverse conditions may occur. On the contrary, if the shear viscosity is too low, for example, it may not be possible to thicken the wet coating thickness during coating, and it may not be possible to obtain the desired thickness after drying.

In the gel pulverized product-containing liquid of the present invention, the solvent may be, for example, a dispersion medium. The above-mentioned dispersion medium (hereinafter also referred to as "coating solvent") is not particularly limited, and examples thereof include gelling solvents and pulverization solvents described later, and are preferably the aforementioned pulverization solvents. The coating solvent includes an organic solvent having a boiling point of 70°C to less than 180°C and a saturated vapor pressure at 20°C of 15 kPa or less.

烷、N,N-二甲基甲醯胺、苯乙烯、四氯乙烯、1,1,1-三氯乙烷、甲苯、1-丁醇、2-丁醇、甲基異丁基酮、甲基乙基酮、甲基環己醇、甲基環己酮、甲基-正丁基酮、異戊醇等。又，前述分散媒中亦可適量含有能使表面張力降低之全氟系界面活性劑或矽系界面活性劑等。The aforementioned organic solvents can be exemplified as carbon tetrachloride, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, trichloroethylene, isobutanol, isopropanol, isoamyl alcohol, 1 -Pentyl alcohol (pentanol), ethyl alcohol (ethanol), ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-butyl ether, ethylene glycol monomethyl Base ether, xylene, cresol, chlorobenzene, isobutyl acetate, isopropyl acetate, isopentyl acetate, ethyl acetate, n-butyl acetate, n-propyl acetate, n-pentyl acetate, cyclohexanol, Cyclohexanone, 1,4-di

alkanes, N,N-dimethylformamide, styrene, tetrachloroethylene, 1,1,1-trichloroethane, toluene, 1-butanol, 2-butanol, methyl isobutyl ketone, Methyl ethyl ketone, methyl cyclohexanol, methyl cyclohexanone, methyl-n-butyl ketone, isoamyl alcohol, etc. In addition, the aforementioned dispersion medium may contain an appropriate amount of a perfluorinated surfactant or a silicon-based surfactant capable of reducing surface tension.

The liquid containing the pulverized product of gel in the present invention includes, for example, a sol particle liquid of the pulverized product in the form of a sol dispersed in the above-mentioned dispersion medium. For example, the liquid containing the pulverized gel of the present invention is coated on a base material and dried, and then chemically cross-linked in a bonding step described later to continuously form a void layer having a film strength of more than a certain level. In addition, the "sol" in the present invention means that the three-dimensional structure of the gel is pulverized, and the pulverized product (that is, porous body sol particles with a nano-three-dimensional structure maintaining a part of the void structure) is dispersed in a solvent to show fluidity. sexual state.

The liquid containing the pulverized gel of the present invention may also contain, for example, a catalyst for chemically bonding the pulverized gel to each other. 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 0.1 to 5% by weight relative to the weight of the pulverized product of the gel.

Furthermore, the liquid containing the pulverized gel of the present invention may further contain, for example, a cross-linking auxiliary agent for indirectly bonding the pulverized gels to each other. The content rate of the aforementioned cross-linking auxiliary agent is not particularly limited, and is, for example, 0.01 to 20% by weight, 0.05 to 15% by weight, or 0.1 to 10% by weight relative to the weight of the pulverized product of the aforementioned gel.

In addition, in the gel pulverized product liquid of the present invention, among the functional groups of the constituent unit monomers of the gel, the proportion of functional groups that do not contribute to the crosslinking structure in the gel can be, for example, 30 mol % or less, 25 mol % or less. % or less, 20 mol% or less, 15 mol% or less, and for example, 1 mol% or more, 2 mol% or more, 3 mol% or more, 4 mol% or more. The ratio of functional groups that do not contribute to the crosslinked structure in the gel can be measured, for example, as follows.

(Measurement method of the ratio of functional groups that do not contribute to the cross-linking structure in the gel) After drying the gel, measure the solid NMR (Si-NMR), and calculate the remaining silanol groups that do not contribute to the cross-linking structure from the NMR peak ratio (functional groups that do not contribute to the cross-linked structure in the gel) ratio. In addition, even if the aforementioned functional groups are other than silanol groups, the ratio of functional groups that do not contribute to the crosslinked structure in the gel can be calculated from the NMR peak ratio.

The following examples illustrate the production method of the gel pulverized product-containing liquid of the present invention. The gel pulverized product-containing liquid of the present invention can be referred to the following description unless otherwise specified.

In the method for producing a liquid containing a ground gel of the present invention, the mixing step is a step of mixing the particles (ground material) of the porous gel with the solvent, which is optional. A specific example of the above-mentioned mixing step may be a step of mixing the pulverized product of a gel-like silicon compound (silicon compound gel) with a dispersion medium. made of silicon compounds. In the present invention, the pulverized product of the aforementioned porous gel can be obtained from the aforementioned porous gel by the gel pulverization step described later. In addition, the pulverized product of the aforementioned porous gel can be obtained, for example, from the aforementioned porous gel subjected to an aging treatment in an aging step described later.

In the method for producing a liquid containing a pulverized gel of the present invention, the gelation step is, for example, a step of gelling a block-shaped porous body in a solvent to form the porous body gel. The specific details of the gelation step For example, it is a step of gelling a silicon compound containing a saturated bond functional group having at least three or less functions in a solvent to form a silicon compound gel.

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

The aforementioned gelation step is, for example, a step of gelling the aforementioned silicon compound as a monomer by a dehydration condensation reaction in the presence of a dehydration condensation catalyst, whereby a silicon compound gel can be obtained. The aforementioned silicon compound gel has, for example, residual silanol groups, and the aforementioned residual silanol groups are suitably adjusted in accordance with the chemical bonding between pulverized products of the aforementioned silicon compound gels to be described later.

In the aforementioned gelling step, the aforementioned silicon compound is not particularly limited as long as it is gelled by a dehydration condensation reaction. For example, the aforementioned silicon compounds are bonded by the aforementioned dehydration condensation. The bond between the aforementioned silicon compounds is, for example, hydrogen bond or intermolecular force bond.

The aforementioned silicon compound can be exemplified by a silicon compound represented by the following formula (1). The silicon compound of the following formula (1) has hydroxyl groups, so the silicon compounds of the following formula (1) can form hydrogen bonding or intermolecular force bonding through these hydroxyl groups.

[chemical formula 3]

In the aforementioned formula (1), for example, X is 2, 3 or 4, and R ¹ is a straight-chain alkyl group or a branched-chain alkyl group. The carbon number of the aforementioned R ¹ is, for example, 1~6, 1~4, 1~2. Examples of the aforementioned straight-chain alkyl group include methyl, ethyl, propyl, butyl, pentyl, and hexyl, and examples of the aforementioned branched-chain alkyl group include isopropyl and isobutyl. The aforementioned X is 3 or 4, for example.

Specific examples of the silicon compound represented by the aforementioned 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 the above-mentioned formula (1), for example, a methyl group. When R ¹ is a methyl group, the aforementioned silicon compound is para(hydroxy)methylsilane. When the aforementioned X is 3, the aforementioned silicon compound is, for example, a trifunctional silane having three functional groups.

[chemical formula 4]

In addition, specific examples of the silicon compound represented by the aforementioned formula (1) include compounds in which X is 4. In this case, the aforementioned silicon compound is, for example, a tetrafunctional silane having four functional groups.

The aforementioned silicon compound may also be, for example, a precursor for forming the aforementioned silicon compound of formula (1) by hydrolysis. For example, the aforementioned precursor may be any one that can generate the aforementioned silicon compound by hydrolysis, and specific examples include the compound represented by the aforementioned formula (2).

When the aforementioned silicon compound is the precursor represented by the aforementioned formula (2), the production method of the present invention may also include, for example, a step of hydrolyzing the aforementioned precursor before the aforementioned gelling step.

The aforementioned hydrolysis method is not particularly limited, for example, it can be carried out by chemical reaction in the presence of a catalyst. Examples of the catalyst include acids such as oxalic acid and acetic acid. The aforementioned hydrolysis reaction can be performed, for example, by slowly mixing the aqueous oxalic acid solution dropwise into the dimethyl oxyphenone solution of the silicon compound precursor at room temperature, and then directly stirring it for about 30 minutes. When the aforementioned silicon compound precursor is hydrolyzed, for example, the alkoxy group of the aforementioned silicon compound precursor can be completely hydrolyzed, so as to more efficiently display the subsequent gelation, aging, heating and immobilization after the formation of the void structure.

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

The silicon compound of the aforementioned monomer is not particularly limited, and can be appropriately selected according to the application of the functional porous body to be produced, for example. In the production of the aforementioned functional porous body, for example, when emphasis is placed on low refractive index properties, the aforementioned silicon compound is preferably the aforementioned trifunctional silane from the viewpoint of excellent low refractive index properties; In the case of resistance), the aforementioned silicon compound is preferably the aforementioned tetrafunctional silane from the viewpoint of excellent scratch resistance. In addition, the aforementioned silicon compound is a raw material of the aforementioned silicon compound gel, and for example, only one type may be used, or two or more types may be used in combination. As a specific example, the aforementioned silicon compound may contain, for example, only the aforementioned trifunctional silane, or only the aforementioned tetrafunctional silane, or may contain both the aforementioned trifunctional silane and the aforementioned tetrafunctional silane, or may further contain other silicon compounds. . When two or more kinds of silicon compounds are used as the silicon compound, the ratio is not particularly limited and can be appropriately set.

The gelation of the porous body such as the aforementioned silicon compound can be performed by, for example, a dehydration condensation reaction between the aforementioned porous bodies. The above-mentioned dehydration condensation reaction, for example, should be carried out in the presence of a catalyst, and the above-mentioned catalyst can be dehydration condensation catalysts such as acid catalyst and alkaline catalyst. The aforementioned acid catalyst has hydrochloric acid, oxalic acid, sulfuric acid, etc., and the aforementioned alkaline catalyst Ammonia, potassium hydroxide, sodium hydroxide, ammonium hydroxide, etc. The aforementioned dehydration condensation catalyst can be an acid catalyst or an alkaline catalyst, and the alkaline catalyst is preferred. In the aforementioned dehydration condensation reaction, the addition amount of the aforementioned catalyst relative to the aforementioned porous body is not particularly limited. For example, relative to 1 mole of the aforementioned porous body, the amount of the catalyst is 0.01-10 moles, 0.05-7 moles, 0.1 ~5 moles.

The gelation of the porous body such as the aforementioned silicon compound is preferably carried out in a solvent, for example. The ratio of the aforementioned porous body to the aforementioned solvent is not particularly limited. The aforementioned solvents can be exemplified as dimethylsulfoxide (DMSO), N-methylpyrrolidone (NMP), N,N-dimethylacetamide (DMAc), dimethylformamide (DMF), γ- Butyrolactone (GBL), acetonitrile (MeCN), ethylene glycol ethyl ether (EGEE), etc. The said solvent may be used, for example by 1 type or in combination of 2 or more types. The solvent used for the aforementioned gelation is also referred to as "solvent for gelation" hereinafter.

The aforementioned gelation conditions are not particularly limited. The treatment temperature of the solvent containing the porous body is, for example, 20-30°C, 22-28°C, 24-26°C, and the treatment time is, for example, 1-60 minutes, 5-40 minutes, or 10-30 minutes. When performing the aforementioned dehydration condensation reaction, the treatment conditions are not particularly limited, and such examples can be cited. When the aforementioned porous body is a silicon compound, by performing the aforementioned gelation, for example, siloxane can be bonded and grown to form the primary particles of the aforementioned silicon compound, and then the aforementioned primary particles can be connected to each other in a beaded shape through the reaction. , to generate a three-dimensional gel.

The gel form of the aforementioned porous body produced in the aforementioned gelation step is not particularly limited. Generally speaking, "gel" refers to a structure in which solutes have lost their independent mobility due to interactions and are in a solidified state. In addition, among gels, generally speaking, a wet gel refers to one containing a dispersion medium and the solute adopts the same structure in the dispersion medium, and a dry gel refers to one having a network structure in which the solute has voids after removing the solvent. In the present invention, it is preferable to use, for example, a wet gel as the silicon compound gel. When the aforementioned porous body gel is a silicon compound gel, the residual silanol groups of the aforementioned silicon compound gel are not particularly limited, and for example, the ranges described below can also be mentioned.

The porous gel obtained by the gelation may be directly supplied to the solvent replacement step and the first pulverization step, or may be subjected to aging treatment in the aging step before the first pulverization step, for example. In the aging step, the gelled porous body (porous body gel) is aged in a solvent. In the aforementioned aging step, the conditions of the aforementioned aging treatment are not particularly limited, for example, the aforementioned porous body gel may be incubated in a solvent at a predetermined temperature. Through the aforementioned aging treatment, for example, for a porous body gel having a three-dimensional structure obtained by gelation, the aforementioned primary particles can be further grown, thereby increasing the size of the aforementioned particles themselves. Also, as a result, the contact state of the aforementioned neck portion where the particles are in contact with each other can be increased from point contact to surface contact. For example, the strength of the gel itself is increased by the aging treatment of the porous gel, and as a result, the strength of the three-dimensional basic structure of the pulverized product after pulverization can be further enhanced. Thus, when a coating film is formed using the gel-containing pulverized product liquid of the present invention, for example, even in the drying step after coating, the pore size of the void structure formed by the accumulation of the aforementioned three-dimensional basic structure can be suppressed, and the The situation that the solvent in the aforementioned coating film volatilizes and shrinks in the aforementioned drying step.

The lower limit of the temperature of the aforementioned aging treatment is, for example, 30°C or higher, 35°C or higher, or 40°C or higher, and the upper limit is, for example, 80°C or lower, 75°C or lower, 70°C or lower, and the range is, for example, 30~80°C, 35~75°C. ℃, 40~70℃. The aforementioned predetermined time is not particularly limited, its lower limit is, for example, more than 5 hours, more than 10 hours, more than 15 hours, its upper limit is, for example, less than 50 hours, less than 40 hours, less than 30 hours, and its range is, for example, 5 to 50 hours, 10 to 10 hours. 40 hours, 15~30 hours. In addition, regarding the optimum conditions for aging, for example, it is preferable to set conditions such that the size increase of the primary particles in the porous body gel and the increase of the neck contact area can be obtained as described above. Also, in the aforementioned aging step, the temperature of the aforementioned aging treatment should take into consideration, for example, the boiling point of the solvent to be used. For example, when the aging process is too high, the solvent may volatilize excessively, and because of the concentration of the coating liquid, there will be unfavorable conditions such as closed pores of the three-dimensional void structure. On the other hand, if the aforementioned aging treatment, for example, when the aging temperature is too low, not only the effect obtained by the aforementioned aging cannot be fully obtained, but also the temperature deviation during the mass production process will increase, and products of poor quality may be produced.

For example, the aging treatment can use the same solvent as that used in the gelation step, and it is preferable to directly perform the reaction product after the gel treatment (ie, the solvent containing the porous gel) directly. For example, when the aforementioned porous body gel is the aforementioned silicon compound gel, the number of moles of residual silanol groups contained in the aforementioned silicon compound gel after aging treatment after gelation is determined by the number of moles used for gelation. The ratio of residual silanol groups when the molar number of alkoxy groups of the raw material (such as the aforementioned silicon compound or its precursor) is 100, the lower limit is, for example, 50% or more, 40% or more, or 30% or more, and the upper limit is, for example, 1 % or less, 3% or less, and 5% or less, the ranges are, for example, 1-50%, 3-40%, 5-30%. For the purpose of increasing the hardness of the silicon compound gel, for example, the lower the molar number of residual silanol groups, the better. If the molar number of residual silanol groups is too high, for example, when forming the aforementioned functional porous body, the void structure may not be maintained until the precursor of the aforementioned functional porous body is cross-linked. On the other hand, if the molar number of residual silanol groups is too low, for example, in the aforementioned bonding step, the precursor of the functional porous body may not be cross-linked, thus failing to impart sufficient film strength. In addition, the above is an example of residual silanol groups. For example, when the aforementioned silicon compound modified with various reactive functional groups is used as the raw material of the aforementioned silicon compound gel, the same phenomenon can be applied to each functional group.

The aforementioned porous body gel obtained by the aforementioned gelation is, for example, subjected to an aging treatment in the aforementioned aging step, then subjected to a solvent replacement step, and then supplied to the aforementioned gel crushing step. In the aforementioned solvent replacement step, the aforementioned solvent may be replaced with other solvents.

In the present invention, the aforementioned gel crushing step is a step of crushing the aforementioned porous body gel as described above. The pulverization may be performed, for example, on the porous gel after the gelation step, or on the aged porous gel that has been subjected to the aging treatment.

As mentioned above, a gel morphology control step for controlling the shape and size of the gel may also be performed before the solvent replacement step (eg, after the aging step). The shape and size of the aforementioned gel controlled in the aforementioned gel shape controlling step are not particularly limited, as described above. The aforementioned gel shape control step can also be performed, for example, by dividing (for example, cutting) the aforementioned gel into three-dimensional (three-dimensional bodies) of appropriate size and shape.

In addition, as described above, after the aforementioned solvent replacement step is performed on the aforementioned gel, the aforementioned gel crushing step is performed. In the aforementioned solvent replacement step, the aforementioned solvent may be replaced with other solvents. Because if the aforementioned solvent is not replaced with the aforementioned other solvents, such as the catalyst and solvent used in the gelation step and the solvent remaining after the aforementioned ripening step, it may affect the further gelation over time and finally produce the gel containing The service life of the pulverized product liquid may reduce the drying efficiency of the coating film formed by using the aforementioned gel-containing pulverized product liquid. In addition, the above-mentioned other solvents in the above-mentioned gel pulverization step are also referred to as "solvent for pulverization" hereinafter.

The above-mentioned pulverization solvent (other solvent) is not particularly limited, and for example, an organic solvent can be used. Examples of the aforementioned organic solvents include solvents having a boiling point of 140°C or lower, a boiling point of 130°C or lower, a boiling point of 100°C or lower, and a boiling point of 85°C or lower. Specific examples include isopropanol (IPA), ethanol, methanol, n-butanol, 2-butanol, isobutanol, pentanol, propylene glycol monomethyl ether (PGME), methylcelluco, acetone, and the like. The aforementioned pulverizing solvent may be used alone, for example, or in combination of two or more.

Also, in the case where the polarity of the solvent for pulverization is very low, for example, the aforementioned solvent replacement step can be divided into multi-stage solvent replacement stages, and in the aforementioned solvent replacement stage, the hydrophilicity of the aforementioned other solvents is lower than that of the aforementioned other solvents. The running stage is lower than the preceding stage. With this setting, for example, the efficiency of solvent replacement can be improved, and the remaining amount of the gel-making solvent (such as DMSO) in the aforementioned gel can be extremely reduced. For a specific example, for example, the aforementioned solvent replacement step can be divided into three stages of solvent replacement. In the first solvent replacement stage, the DMSO in the gel is first replaced with water, and then in the second solvent replacement stage. The aforementioned water in the gel was replaced with IPA, and then the aforementioned IPA in the gel was replaced with isobutanol in the third replacement stage.

The combination of the solvent for gelation and the solvent for pulverization is not particularly limited, and examples include combinations of DMSO and IPA, combinations of DMSO and ethanol, combinations of DMSO and isobutanol, combinations of DMSO and n-butanol, and the like. In this way, by replacing the solvent for gelation with the solvent for pulverization, a relatively uniform coating film can be formed, for example, in the coating film formation described later.

The aforementioned solvent replacement step is not particularly limited, and can be performed, for example, in the following manner. That is, first, the gel (such as the gel after the aforementioned aging treatment) prepared by the aforementioned gel manufacturing step is immersed or contacted with the aforementioned other solvents, so that the catalyst for gel manufacturing in the aforementioned gel is formed by condensation reaction. Alcohol components, water, etc. are dissolved in the aforementioned other solvents. Thereafter, the solvent that has impregnated or contacted the aforementioned gel is discarded, and the aforementioned gel is impregnated or exposed to a new solvent again. This procedure is repeated until the remaining amount of the solvent for gel production in the aforementioned gel reaches the desired amount. The immersion time per one time is, for example, 0.5 hours or more, 1 hour or more, or 1.5 hours or more, and the upper limit is not particularly limited, for example, it is 10 hours or less. In addition, the impregnation with the above-mentioned solvent can also be handled in such a manner that the above-mentioned solvent is continuously brought into contact with the gel. Moreover, the temperature in the said immersion is not specifically limited, For example, it may be 20-70 degreeC, 25-65 degreeC, or 30-60 degreeC. Heating enables rapid progress of the solvent exchange, which requires only a small amount of solvent necessary for the exchange, but the solvent exchange can also be easily performed at room temperature. Also, for example, when the aforementioned solvent replacement step is divided into multi-stage solvent replacement stages, each stage of the aforementioned multi-stage solvent replacement steps can also be performed in the same manner as described above.

In addition, for example, the above-mentioned solvent replacement step may be divided into multi-stage solvent replacement stages, and the hydrophilicity of the aforementioned other solvents is lower in the subsequent stages than in the preceding stages. In this way, the replacement solvent (other solvents mentioned above) can be gradually changed from a highly hydrophilic solvent to a low hydrophilic (high hydrophobic) solvent, thereby making the gel-making solvent in the gel The remaining amount has become very small. With the method described above, for example, a further voided layer with a high porosity (and thus, for example, a low refractive index) can be produced.

After the aforementioned solvent replacement step, the residual amount of the gel-making solvent in the aforementioned gel is preferably less than 0.005 g/ml, more preferably less than 0.001 g/ml, and especially preferably less than 0.0005 g/ml. The lower limit of the residual amount of the solvent for gel production in the aforementioned gel is not particularly limited, for example, it may be zero, the detection limit value or less.

After performing the solvent replacement step, the remaining amount of the solvent for gel production in the gel can be measured, for example, by the following method.

(Measurement method of remaining amount of solvent for gel production in gel) 0.2 g of gel was collected, 10 ml of acetone was added, and it was extracted by shaking at room temperature at 120 rpm for 3 days using a shaker. 1 µl of the extract was injected into a gas chromatography analyzer (manufactured by Aglent, trade name 7890A) for analysis. In addition, in order to confirm the reproducibility of the measurement, for example, n=2 (the number of times of measurement is 2 times) or more may be sampled and measured. Further, a test line was prepared from the sample, and the amount of each component per 1 g of the gel was obtained, and the remaining amount of the gel-making solvent per 1 g of the gel was calculated.

When the aforementioned solvent replacement step is divided into multi-stage solvent replacement steps, and the hydrophilicity of the aforementioned other solvent is lower in the later stage than in the preceding stage, the aforementioned other solvent (solvent for replacement) is not particularly limited. However, in the aforementioned solvent replacement stage performed last, the aforementioned other solvent (solvent for replacement) is preferably a solvent for the formation of the void layer. Examples of the aforementioned solvent for forming the void layer include solvents having a boiling point of 140° C. or lower. In addition, examples of the aforementioned solvent for void layer production include alcohols, ethers, ketones, ester-based solvents, aliphatic hydrocarbon-based solvents, aromatic-based solvents, and the like. Specific examples of alcohols having a boiling point of 140° C. or less include isopropanol (IPA), ethanol, methanol, n-butanol, 2-butanol, isobutanol (IBA), 1-pentanol, and 2-pentanol. Specific examples of ethers having a boiling point of 140° C. or lower include propylene glycol monomethyl ether (PGME), methylcelluloid, and ethylcelluloid. Specific examples of ketones having a boiling point of 140° C. or lower include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclopentanone. Specific examples of ester-based solvents having a boiling point of 140° C. or less include ethyl acetate, butyl acetate, isopropyl acetate, and n-propyl acetate. Specific examples of the aliphatic hydrocarbon solvent having a boiling point of 140° C. or less include hexane, cyclohexane, heptane, octane, and the like. Specific examples of the aromatic solvent having a boiling point of 140° C. or less include toluene, benzene, xylene, anisole, and the like. During coating, the solvent for forming the void layer is preferably an alcohol, ether or aliphatic hydrocarbon solvent from the viewpoint of not easily corroding the substrate (such as a resin film). Moreover, the above-mentioned pulverizing solvent may be used, for example, by 1 type or in combination of 2 or more types. In particular, isopropanol (IPA), ethanol, n-butanol, 2-butanol, isobutanol (IBA), pentanol, propylene glycol monomethyl ether ( PGME), methyl celluloid, heptane, octane are suitable. In particular, in order to suppress the scattering of the particles of the gel material (such as silicon dioxide compound), the saturated vapor pressure of the solvent for forming the void layer should not be too high (the volatility should not be too high). Such solvents are preferably solvents having aliphatic groups having 3 or more carbon atoms, and solvents having aliphatic groups having 4 or more carbon atoms are more preferable. The aforementioned solvent having an aliphatic group having 3 or more carbon atoms may also be, for example, alcohol. Such solvents are specifically such as isopropanol (IPA), isobutanol (IBA), n-butanol, 2-butanol, 1-pentanol, 2-pentanol, and isobutanol (IBA) Excellent.

The aforementioned other solvents (solvents for substitution) other than the aforementioned solvent substitution stage performed last are not particularly limited, and examples thereof include alcohols, ethers, and ketones. Specific examples of the alcohol include isopropanol (IPA), ethanol, methanol, n-butanol, 2-butanol, isobutanol (IBA), pentanol, and the like. Specific examples of ethers include propylene glycol monomethyl ether (PGME), methyl-celluloid, ethyl-celluloid, and the like. Specific examples of ketones include acetone and the like. The aforementioned other solvent (solvent for replacement) may be used as long as it can replace the aforementioned solvent for gel production or the aforementioned other solvent (solvent for replacement) in the previous stage. In addition, it is preferable that the other solvents (replacement solvents) other than the above-mentioned solvent replacement step performed last are solvents that do not remain in the gel at the end or that are less likely to corrode the substrate (such as a resin film) during coating even if they remain. . From the viewpoint of not easily corroding the base material (such as a resin film) during coating, the other solvent (replacement solvent) other than the above-mentioned solvent replacement stage carried out at the end is preferably alcohol. In this way, it is preferable that the aforementioned other solvent in at least one stage of the aforementioned multi-stage solvent replacement stage is alcohol.

In the initial solvent replacement stage, the other solvent may be, for example, water or a mixed solvent containing water in any ratio. As long as it is water or a mixed solvent containing water, it has high compatibility with a highly hydrophilic gel-making solvent (such as DMSO), so it is easy to replace the above-mentioned gel-making solvent, and it is also preferable in terms of cost.

The aforementioned multi-stage solvent replacement stage may also include the following stages: the stage in which the aforementioned other solvent is water; the subsequent stage in which the aforementioned other solvent is a solvent having an aliphatic group with a carbon number of 3 or less; and the subsequent aforementioned Other solvents are solvents having an aliphatic group having 4 or more carbon atoms. Also, 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 an alcohol. The alcohol having an aliphatic group having 3 or less carbon atoms is not particularly limited, and examples thereof include isopropanol (IPA), ethanol, methanol, and n-propyl alcohol. The alcohol having an aliphatic group having 4 or more carbon atoms is not particularly limited, and examples thereof include n-butanol, 2-butanol, isobutanol (IBA), and pentanol. For example, the solvent having an aliphatic group having 3 or less carbon atoms may be isopropanol, while the solvent having an aliphatic group having 4 or more carbon atoms may be isobutanol.

The inventors of the present invention have found that it is very important to focus on the remaining amount of the aforementioned solvent for gel production in order to form a void layer having film strength under relatively mild conditions of, for example, 200°C or lower. This insight has not been disclosed in the aforementioned prior art including patent documents and non-patent documents, and is an explanation independently discovered by the inventors.

In this way, the reason (mechanism) for producing a low-refractive-index void layer by reducing the remaining amount of the gel-forming solvent in the gel is not clear, but it can be speculated as follows, for example. That is, as mentioned above, in order to carry out the gelation reaction, the solvent for gel production is preferably a high boiling point solvent (such as DMSO, etc.). In addition, when the sol solution obtained from the aforementioned gel is applied and dried to form a void layer, it is difficult to use the usual drying temperature and drying time (not particularly limited, but for example, at 100° C. for 1 minute, etc.) The aforementioned high boiling point solvent was completely removed. Because, once the drying temperature is too high or the drying time is too long, problems such as substrate degradation may occur. In addition, the high-boiling-point solvent remaining during the coating and drying process will enter between the pulverized products of the gel, causing the pulverized products to slide against each other so that the pulverized products can be packed closely to reduce the porosity. Therefore, it is speculated that Difficult to visualize low refractive index. That is, conversely, by reducing the residual amount of the above-mentioned high boiling point solvent, this phenomenon can be suppressed and a low refractive index can be exhibited. However, these are only examples of the presumed mechanism and do not limit the present invention in any way.

In addition, in the present invention, the "solvent" (such as a solvent for gel production, a solvent for void layer production, a solvent for replacement, etc.) does not need to dissolve the gel or its pulverization, for example, the aforementioned gel or its pulverization may be dissolved. substances, etc. are dispersed or precipitated in the aforementioned solvents.

The above-mentioned solvent for gel production may have a boiling point of 140° C. or higher, for example, as described above.

The aforementioned solvent for gel production is, for example, a water-soluble solvent. In addition, in the present invention, the "water-soluble solvent" means a solvent that can be mixed with water at any ratio.

When the aforementioned solvent replacement step is divided into multi-stage solvent replacement steps, the method is not particularly limited. For example, each solvent replacement step can be performed in the following manner. That is, firstly, the aforementioned gel is immersed or contacted with the aforementioned other solvent, and the catalyst for gel production, the alcohol component produced by the condensation reaction, water, etc. in the aforementioned gel are dissolved in the aforementioned other solvent. Thereafter, the solvent that has impregnated or contacted the aforementioned gel is discarded, and the aforementioned gel is impregnated or exposed to a new solvent again. This procedure is repeated until the remaining amount of the solvent for gel production in the aforementioned gel reaches the desired amount. The immersion time per one time is, for example, 0.5 hours or more, 1 hour or more, or 1.5 hours or more, and the upper limit is not particularly limited, for example, it is 10 hours or less. In addition, the impregnation with the above-mentioned solvent can also be handled in such a manner that the above-mentioned solvent is continuously brought into contact with the gel. Moreover, the temperature in the said immersion is not specifically limited, For example, it may be 20-70 degreeC, 25-65 degreeC, or 30-60 degreeC. Heating enables rapid progress of the solvent exchange, which requires only a small amount of solvent necessary for the exchange, but the solvent exchange can also be easily performed at room temperature. This solvent replacement step is carried out several times, and the aforementioned other solvent (replacement solvent) is gradually replaced from a highly hydrophilic solvent to a low hydrophilic (high hydrophobic) solvent. In order to remove the highly hydrophilic gel-making solvent (such as DMSO, etc.), as mentioned above, it is simple and efficient to use water as the replacement solvent at the beginning. Next, after removing DMSO and the like with water, the water in the gel is replaced, for example, in the order of isopropanol⇒isobutanol (solvent for coating). That is, the compatibility between water and isobutanol is low, so after replacing it with isopropanol for a while, and then replacing it with isobutanol for coating the solvent, the solvent replacement can be performed efficiently. However, this is an example, and as mentioned above, the said other solvent (solvent for substitution) is not specifically limited.

In the present invention, the manufacturing method of the gel is as described above, and the above-mentioned solvent replacement stage can also be carried out several times, and the above-mentioned other solvents (replacement solvents) are slowly changed from a highly hydrophilic solvent to a low-hydrophilic ( highly hydrophobic solvents. Thereby, as mentioned above, the residual amount of the solvent for gel production in the said gel can be extremely reduced. Not only that, but for example, compared to one-stage solvent replacement using only the solvent for coating, the amount of solvent used can be reduced to an extreme level, and thus the cost can also be reduced.

Then, after the solvent replacement step, a gel pulverization step is performed, that is, the gel is pulverized in the pulverization solvent. For another example, as mentioned above, after the solvent replacement step and before the gel pulverization step, the gel concentration measurement may be performed as required, and then the gel concentration adjustment step may be performed as required. The measurement of the gel concentration after the solvent replacement step and before the gel pulverization step can be performed, for example, as follows. That is, first, after the above-mentioned solvent replacement step, the gel is taken out from the above-mentioned other solvent (solvent for pulverization). The gel, for example, has been controlled into an agglomerate of appropriate shape and size (eg block) by the aforementioned gel shape control step. Next, after removing the solvent adhering to the agglomerate of the gel, the concentration of the solid content in one gel agglomerate was measured by the gravimetric drying method. At this time, in order to obtain the reproducibility of the measured value, a plurality of (for example, 6) agglomerates taken out at random are used for measurement, and the average value and the variance of the value are calculated. In the concentration adjustment step, for example, the gel concentration of the gel-containing liquid can be reduced by further adding the other solvent (solvent for pulverization). In addition, in the aforementioned concentration adjustment step, conversely, the gel concentration of the aforementioned gel-containing liquid may be increased by evaporating the aforementioned other solvent (solvent for pulverization).

In the method for producing a liquid containing a ground gel product of the present invention, as described above, the gel pulverization step may be performed in one stage, but it is preferably divided into a plurality of pulverization stages. Specifically, for example, the aforementioned first pulverization stage and the aforementioned second pulverization stage can be performed. In addition, in the above-mentioned gel pulverization step, a gel pulverization step may be further performed in addition to the aforementioned first pulverization step and the aforementioned second pulverization step. That is, in the production method of the present invention, the above-mentioned gel pulverization step is not limited to two pulverization stages, but may include three or more pulverization stages.

Hereinafter, the above-mentioned first crushing stage and the above-mentioned second crushing stage will be described.

The aforementioned first pulverization step is a step of pulverizing the aforementioned porous body gel. The second crushing stage is a step of further crushing the particles of the porous body gel after the first crushing stage.

The volume average particle diameter of the particles of the porous gel obtained through the first pulverization step and the volume average particle diameter of the particles of the porous gel obtained through the second pulverization step are as described above. The method for measuring the above-mentioned volume average particle diameter is also the same as above, for example.

The shear viscosity of the gel-containing pulverized product liquid immediately after the first pulverization stage and the shear viscosity immediately after the second pulverization stage are, for example, as described above. The method for measuring the aforementioned shear viscosity is, for example, the same as described above.

In addition, as mentioned above, it is also possible to measure the gel concentration of the gel-containing liquid immediately after the first crushing stage, and only supply the liquid whose gel concentration is within a predetermined value range to the second crushing stage, In order to manage the concentration of the aforementioned gel-containing liquid.

The pulverization method of the aforementioned porous body gel is not particularly limited, for example, it can be carried out by the following devices: high-pressure non-media pulverization device, ultrasonic homogenizer, high-speed rotary homogenizer, high-pressure extrusion pulverization device, other wet-type methods using cavitation phenomenon No medium crushing device etc. The aforementioned first pulverization stage and the aforementioned second pulverization stage may be performed by the same pulverization method, or mutually different pulverization methods may be performed, but it is preferable to perform mutually different pulverization methods.

As for the pulverization method, at least one of the first pulverization step and the second pulverization step is preferably performed by a method of pulverizing the porous body gel by controlling energy. The aforementioned method of pulverizing the porous gel by controlling energy may, for example, be performed using a high-pressure medialess pulverizing device.

In the method of crushing the aforementioned porous gel by ultrasonic wave, although the crushing strength is strong, it is difficult to control (adjust) the crushing. On the other hand, in the method of pulverizing the porous gel by controlling energy, pulverization can be performed while controlling (adjusting) the pulverization. Thereby, a uniform gel-containing pulverized product liquid can be produced with a limited amount of work. Therefore, for example, it is possible to manufacture the liquid containing the pulverized gel in mass production steps.

Devices that perform media crushing such as bead mills, for example, physically destroy the gel void structure during crushing. In contrast, cavitation crushing devices such as homogenizers use high-speed shearing because they are media-free. The shearing force peels off the joint surfaces of the porous particles that have already been included in the three-dimensional structure of the gel and have a weaker binding force. In this way, a new three-dimensional structure of the sol can be obtained by pulverizing the aforementioned porous body gel. The aforementioned three-dimensional structure, for example, can maintain a void structure with a particle size distribution within a certain range when forming a coating film. The build-up on drying re-forms the void structure. The aforementioned pulverization conditions are not particularly limited. For example, it is preferable to pulverize the gel without volatilizing the solvent by instantaneously imparting a high-speed flow. For example, it is preferable to pulverize so as to become a pulverized product with uneven particle size (for example, volume average particle diameter or particle size distribution) as described above. Assuming that when the amount of work such as crushing time and intensity is insufficient, for example, if there are coarse particles remaining, not only the dense pores cannot be formed, but also the appearance defects may increase, so that high quality cannot be obtained. On the other hand, if the above-mentioned workload is too much, for example, sol particles with a finer particle size distribution than desired may be formed, and the size of voids accumulated after coating and drying may be fined, so that the desired porosity may not be achieved.

In at least one of the first pulverization stage and the second pulverization stage, it is preferable to control the pulverization of the porous body while measuring the shear viscosity of the liquid. Specific methods can be exemplified by adjusting the sol liquid with desired shear viscosity and excellent uniformity in the middle stage of the aforementioned pulverization stage, monitoring the shear viscosity of the aforementioned liquid on-line (in-line) and Feedback to the method of the aforementioned crushing stage. Thereby, it is possible to manufacture a gel-containing pulverized product liquid having both desired shear viscosity and extremely excellent uniformity. Therefore, for example, the properties of the liquid containing the above-mentioned pulverized gel can be controlled according to its use.

After the aforementioned pulverization stage, when the aforementioned porous body gel is the aforementioned silicon compound gel, the ratio of residual silanol groups contained in the aforementioned pulverized product is not particularly limited, for example, as shown for the aforementioned silicon compound gel after aging treatment Same range.

In the production method of the present invention, a classification step may be further performed after at least one of the aforementioned gel pulverization steps (the aforementioned first pulverization stage and the aforementioned second pulverization stage). The aforementioned classification step is to classify the particles of the aforementioned porous body gel. The aforementioned "classification" refers to, for example, classifying the particles of the aforementioned porous body gel according to their particle diameters. The classification method is not particularly limited, and it can be carried out with a sieve. In this way, by performing the pulverization process in multiple stages, as described above, the pulverized product of the porous body gel can be extremely uniform. Therefore, when the pulverized product of the aforementioned porous body gel is applied to applications such as optical members, the appearance of the aforementioned optical members and the like can be improved. In addition, by classifying the pulverized material of the porous gel, the optical member and the like can have a good appearance.

After the above-mentioned gel pulverization step and any of the above-mentioned classification steps, the ratio of the aforementioned pulverized product in the aforementioned solvent containing the aforementioned pulverized product is not particularly limited, for example, the above-mentioned conditions in the above-mentioned gel pulverized product-containing liquid of the present invention can be cited. . The ratio may be, for example, a condition of the solvent itself containing the pulverized product after the gel pulverizing step, or may be a condition adjusted after the gel pulverizing step and before use as a liquid containing the pulverized gel.

A liquid (such as a suspension) containing the aforementioned microporous particles (crushed product of a gel-like compound) can be produced in the above-mentioned manner. In addition, a liquid containing the microporous particles and the catalyst can be produced by adding a catalyst for chemically bonding the microporous particles to each other after producing the liquid containing the microporous particles or during the production step. The amount of the catalyst added is not particularly limited, but is, for example, 0.01 to 20% by weight, 0.05 to 10% by weight, or 0.1 to 5% by weight relative to the weight of the ground product of the gel-like silicon compound. The aforementioned catalyst may be, for example, a catalyst that promotes the cross-linking of the microporous particles. The chemical reaction for chemically bonding the microporous particles to each other preferably utilizes the dehydration condensation reaction of the residual silanol groups contained in the silica sol molecules. By using the aforementioned catalyst to promote the reaction between the hydroxyl groups of the silanol groups, it is possible to achieve continuous film formation that hardens the void structure in a short period of time. The above-mentioned catalysts include, for example, photoactive catalysts and thermally active catalysts. By means of the photoactive catalyst, for example, the microporous particles can be chemically bonded (eg, cross-linked) to each other without heating in the step of forming the void layer. Thereby, for example, in the step of forming the void layer, shrinkage of the entire void layer is less likely to occur, so that a high porosity can be maintained. Also, in addition to the aforementioned catalyst, a substance generating a catalyst (catalyst generating agent) may also be used or simply replaced. For example, in addition to the aforementioned photoactive catalysts, substances that generate catalysts by light (photocatalyst generators) can also be used or simply replaced, and in addition to the aforementioned thermally active catalysts, substances that generate catalysts by heat can also be used (thermal catalyst generator) or simply replace it. The aforementioned photocatalyst generators are not particularly limited, and may include, for example, photobase generators (substances that produce alkaline catalysts by light irradiation), photoacid generators (substances that produce acidic catalysts by light irradiation), and the like. Generator is appropriate. The aforementioned photobase generator can be for example 9-anthrylmethyl N, N-diethylcarbamate (9-anthrylmethyl N, N-diethylcarbamate, trade name WPBG-018), (E)-1-[3 -(2-Hydroxyphenyl)-2-acryloyl]piperidine ((E)-1-[3-(2-hydroxyphenyl)-2-propenoyl]piperidine, trade name WPBG-027), 1-(anthracene Quinone-2-yl)ethyl imidazolecarboxylate (1-(anthraquinon-2-yl)ethyl imidazolecarboxylate, trade name WPBG-140), 2-nitrobenzyl-4-methylpropionyloxypiperidine -1-carboxylate (trade name WPBG-165), 1,2-diisopropyl-3-[bis(dimethylamino)methyleneguanidine]2-(3-benzoylphenyl ) propionate (trade name WPBG-266), 1,2-dicyclohexyl 4,4,5,5-tetramethyldiguanidinium n-butyltriphenyl borate (trade name WPBG-300), and 2 -(9-oxodibenzopyran-2-yl)propanoic acid 1,5,7-triazabicyclo[4.4.0]dec-5-ene (Tokyo Chemical Industry Co., Ltd.) , a compound containing 4-piperidinemethanol (trade name HDPD-PB100: manufactured by Heraeus), etc. In addition, the aforementioned trade names containing "WPBG" are all trade names of Wako Pure Chemical Industries, Ltd. The aforementioned photoacid generators can be exemplified as aromatic percited salts (trade name SP-170: ADEKA Company), triaryl percited salts (trade name CPI101A: San-Apro Ltd.), aromatic iodonium salts (trade name Irgacure250: Ciba Japan company), etc. In addition, the catalyst for chemically bonding the aforementioned microporous particles is not limited to the aforementioned photoactive catalyst and the aforementioned photocatalyst generating agent, for example, it may also be a thermally active catalyst or a thermal catalyst generating agent. The catalysts for chemically bonding the aforementioned microporous particles include alkaline catalysts such as potassium hydroxide, sodium hydroxide, and ammonium hydroxide, and acid catalysts such as hydrochloric acid, acetic acid, and oxalic acid. Among them, an alkaline catalyst is suitable. The catalyst or catalyst generating agent for chemically bonding the microporous particles to each other can be added to the sol particle liquid (such as a suspension) containing the pulverized material (microporous particles) just before coating, for example. It can be used, or it can be used as a mixture in which the aforementioned catalyst or catalyst generating agent has been mixed into a solvent. The aforementioned mixed solution may be, for example, directly adding a coating solution dissolved in the aforementioned sol particle liquid, a solution in which the aforementioned catalyst or catalyst generating agent is dissolved in a solvent, or a dispersion in which the aforementioned catalyst or catalyst generating agent is dispersed in a solvent. liquid. The aforementioned solvent is not particularly limited, and examples thereof include water, buffer solution, and the like.

[2-3. Manufacturing method of low refractive index layer and manufacturing method of optical sheet for light guide plate type liquid crystal display] The method of manufacturing low refractive index layer and the optical sheet for light guide plate type liquid crystal display of the present invention will be described below with examples The manufacturing method. The following description will mainly focus on the case where the low refractive index layer of the present invention is a porous polysiloxane body formed of a silicon compound. However, the low refractive index layer of the present invention is not limited to the porous polysiloxane. When the low-refractive-index layer of the present invention is other than the polysiloxane porous body, the following description is applicable unless otherwise specified.

The manufacturing method of the low refractive index layer of the present invention includes the following steps, for example: a step of forming a precursor, using the liquid containing pulverized gel of the present invention to form the precursor of the low refractive index layer; and a combining step of making the precursor The above-mentioned pulverized products contained in the above-mentioned gel pulverized product-containing liquid are chemically bonded to each other. The foregoing precursor may also be called a coating film, for example.

According to the manufacturing method of the low-refractive-index layer of the present invention, for example, a porous structure capable of functioning as an air layer can be formed. The reason is presumed as follows, but the present invention is not limited by this presumption. The following examples illustrate the case where the low-refractive index layer of the present invention is a polysiloxane porous body.

The above-mentioned gel-containing pulverized product liquid of the present invention used in the above-mentioned production method of the polysiloxane porous body contains the above-mentioned silicon compound gel pulverized product, so the three-dimensional structure of the above-mentioned gel-like silica compound is dispersed into a three-dimensional basic structure status. Therefore, in the production method of the aforementioned polysiloxane porous body, for example, if the aforementioned precursor (such as a coating film) is formed using the liquid containing the aforementioned gel pulverized product, the aforementioned three-dimensional basic structure will be piled up to form the aforementioned three-dimensional basic structure. as the main void structure. That is, by using the aforementioned method for producing a polysiloxane porous body, it is possible to form a novel three-dimensional structure that is completely different from the three-dimensional structure of the aforementioned silicon compound gel and formed from the aforementioned pulverized product of the aforementioned three-dimensional basic structure. In addition, in the production method of the aforementioned polysiloxane porous body, the aforementioned pulverized materials are further chemically bonded to each other, so the aforementioned novel three-dimensional structure can be immobilized. Therefore, although the aforementioned porous polysiloxane body produced by the method for producing the aforementioned porous polysiloxane body has a structure having voids, it can still maintain sufficient strength and flexibility. The low-refractive-index layer (such as polysiloxane porous body) obtained by the present invention can be used, for example, as a member utilizing voids in products in a wide range of fields, such as heat-insulating materials, sound-absorbing materials, optical components, printing ink image-receiving layers, etc. , In addition, it is also possible to produce laminated films that have been endowed with various functions.

Unless otherwise specified, the method for producing the low-refractive index layer of the present invention can refer to the above-mentioned description of the pulverized gel-containing liquid of the present invention.

In the step of forming the precursor of the porous body, for example, the gel-containing pulverized product of the present invention is liquid-coated on the substrate. For example, after the gel-containing pulverized product liquid of the present invention is coated on a substrate and the aforementioned coating film is dried, the aforementioned pulverized products are chemically bonded (such as cross-linked) through the aforementioned combining step, and can be continuously formed into a film with A low-refractive index layer with film strength above a certain level.

The coating amount of the liquid containing the pulverized gel on the substrate is not particularly limited, and can be appropriately set according to the desired thickness of the low-refractive index layer of the present invention, for example. As a specific example, when forming the aforementioned polysiloxane porous body with a thickness of 0.1 to 1000 μm, the coating amount of the liquid containing the pulverized gel on the aforementioned base material is per ¹ m of the aforementioned base material area, for example, the aforementioned Crushed matter 0.01~60000μg, 0.1~6000μg, 1~50μg. The ideal coating amount of the above-mentioned liquid containing pulverized gel is related to, for example, the concentration of the liquid or the method of coating, so it is difficult to make a univocal definition. In consideration of productivity, it is better to apply as thin a layer as possible. If the coating amount is too large, for example, the possibility of drying in a drying oven before the solvent evaporates becomes high. In this way, before the nano-pulverized sol particles settle and accumulate in the solvent to form a void structure, the solvent may dry to hinder the formation of voids and greatly reduce the void ratio. On the other hand, once the coating amount is too thin, the risk of coating shrinkage (cissing) may increase due to unevenness of the substrate, unevenness of hydrophilicity and hydrophobicity, etc.

After coating the liquid containing the pulverized gel on the substrate, drying may be performed on the precursor (coating film) of the porous body. The purpose of the drying process is not only to remove the solvent in the precursor of the porous body (solvent contained in the liquid containing the ground gel), but also to settle and accumulate the sol particles to form a void structure during the drying process. . The temperature of the aforementioned drying treatment is, for example, 50~250°C, 60~150°C, 70~130°C, and the time of the aforementioned drying treatment is, for example, 0.1~30 minutes, 0.2~10 minutes, 0.3~3 minutes. Regarding the drying treatment temperature and time, for example, low temperature and short time are preferable in terms of continuous productivity and high porosity. If the conditions are too severe, for example, when the substrate is a resin film, when it is close to the glass transition temperature of the substrate, the substrate will be stretched in the drying oven and the void structure may be formed immediately after coating. Defects such as cracks. On the other hand, if the conditions are too loose, for example, because the residual solvent is contained at the time of leaving the drying oven, it may cause appearance defects such as scratches when rubbing against the roller in the next step.

The aforementioned drying treatment may be, for example, natural drying, heat drying, or reduced-pressure drying. The aforementioned drying method is not particularly limited, for example, a general heating mechanism can be used. The aforementioned heating mechanism can be, for example, a hot air heater, a heating roller, a far-infrared heater, and the like. Among them, under the premise of continuous industrial production, heating and drying should be used. Also, regarding the solvents that can be used, when the purpose is to suppress the shrinkage stress that occurs with the volatilization of the solvent during drying and the subsequent cracking of the low-refractive index layer (the aforementioned polysiloxane porous body), the solvent with low surface tension should be used. Solvents are preferred. The above-mentioned solvents can be, for example, lower alcohols represented by isopropanol (IPA), hexane, perfluorohexane, etc., but are not limited thereto.

The above-mentioned substrates are not particularly limited, for example, it is suitable to use: thermoplastic resin substrates, glass substrates, inorganic substrates represented by silicon, plastics formed by thermosetting resins, semiconductors and other components, carbon nanotubes Representative carbon fiber-based materials, etc., but not limited to these. The form of the above-mentioned substrate can be, for example, a film, a thin plate, and the like. The aforementioned thermoplastic resins can be exemplified such as polyethylene terephthalate (PET), acrylic acid, cellulose acetate propionate (CAP), cycloolefin polymer (COP), triacetate (TAC), polyethylene naphthalate Ethylene glycol (PEN), polyethylene (PE), polypropylene (PP), etc.

In the manufacturing method of the low-refractive-index layer of the present invention, the bonding step is a step of chemically bonding the pulverized matter contained in the precursor (coating film) of the porous body to each other. By the bonding step, for example, the three-dimensional structure of the pulverized product of the precursor of the porous body can be immobilized. When using conventional sintering for immobilization, for example, high temperature treatment above 200°C is used to stimulate the dehydration condensation of silanol groups to form siloxane bonds. In the aforementioned bonding step of the present invention, by reacting various additives that catalyze the above-mentioned dehydration condensation reaction, for example, when the base material is a resin film, the aforementioned base material can not be damaged, and it can be used at a lower temperature around 100°C. At drying temperature and short processing time of only a few minutes, the void structure is continuously formed and immobilized.

The aforementioned method of chemical bonding is not particularly limited, for example, it can be appropriately determined according to the type of the aforementioned gel (such as silicon compound gel). As a specific example, the aforementioned chemical bonding can be performed, for example, by chemical cross-linking between the aforementioned pulverized objects. Other considerations include adding inorganic particles such as titanium oxide to the aforementioned pulverized objects so that the aforementioned inorganic particles and The aforementioned pulverized products are chemically cross-linked. In addition, there are also cases where biocatalysts such as enzymes are supported, or other parts other than the active sites of the catalyst are chemically cross-linked with the above-mentioned pulverized material. Therefore, the present invention is not limited to the low-refractive-index layer formed by the above-mentioned sol particles, but also can be extended to organic-inorganic hybrid low-refractive-index layer, host-guest low-refractive-index layer, etc., but not limited thereto.

For example, the above-mentioned combining step can be performed by a chemical reaction in the presence of a catalyst according to the type of the pulverized product of the above-mentioned gel (such as silicon compound gel). The chemical reaction of the present invention preferably utilizes the dehydration condensation reaction of the residual silanol groups contained in the pulverized silicon compound gel. By using the aforementioned catalyst to promote the reaction between the hydroxyl groups of the silanol groups, it is possible to achieve continuous film formation that hardens the void structure in a short period of time. The aforementioned catalysts may include alkaline catalysts such as potassium hydroxide, sodium hydroxide, and ammonium hydroxide, and acid catalysts such as hydrochloric acid, acetic acid, and oxalic acid, but are not limited thereto. The catalyst for the aforementioned dehydration condensation reaction is particularly preferably an alkaline catalyst. In addition, a photoacid generating catalyst, a photobase generating catalyst, or the like that exhibits catalytic activity by irradiation with light (for example, ultraviolet rays) is also suitably used. The photoacid generation catalyst and the photobase generation catalyst are not particularly limited, and are as described above, for example. As mentioned above, the above-mentioned catalyst is preferably added to the sol particle liquid containing the above-mentioned pulverized material just before coating, or it is preferably used as a mixed liquid in which the above-mentioned catalyst is mixed in a solvent. The mixed liquid may be, for example, a coating liquid in which the sol particle liquid is directly added, 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 aforementioned solvent is not particularly limited, and as mentioned above, examples thereof include water, buffer solution, and the like.

Also, for example, a crosslinking auxiliary agent for indirect bonding of the above-mentioned pulverized gels may be further added to the gel-containing liquid of the present invention. The cross-linking auxiliary agent will intervene between the particles (the above-mentioned pulverized products), so that the particles and the cross-linking auxiliary agent can interact or combine each other, so that the particles that are slightly separated by distance can also be bonded to each other, thereby effectively increasing the strength. . The aforementioned crosslinking auxiliary agent is preferably a multi-crosslinking silane monomer. The aforementioned multi-crosslinked silane monomer specifically has, for example, 2 or more and 3 or less alkoxysilyl groups, and the chain length between the alkoxysilyl groups may be 1 or more and 10 or less, and may contain elements other than carbon. The aforementioned cross-linking auxiliary agent can be exemplified for example: bis(trimethoxysilyl)ethane, bis(triethoxysilyl)ethane, bis(trimethoxysilyl)methane, bis(triethoxysilyl)methane, bis(trimethoxysilyl)methane, bis(trimethoxysilyl)methane, (triethoxysilyl)propane, bis(trimethoxysilyl)propane, bis(triethoxysilyl)butane, bis(trimethoxysilyl)butane, bis(triethoxysilyl)pentane, Bis(trimethoxysilyl)pentane, bis(trimethoxysilyl)hexane, bis(trimethoxysilyl)hexane, bis(trimethoxysilyl)-N-butyl-N-propyl-ethyl Alkane-1,2-diamine, ginseng-(3-trimethoxysilylpropyl) isocyanate, ginseng-(3-triethoxysilylpropyl) isocyanate, etc. The addition amount of the crosslinking auxiliary agent is not particularly limited, for example, it is 0.01-20% by weight, 0.05-15% by weight or 0.1-10% by weight relative to the weight of the pulverized silicon compound.

The chemical reaction in the presence of the aforementioned catalyst can be carried out, for example, by irradiating or heating the aforementioned coating film containing the aforementioned catalyst or catalyst generator previously added to the aforementioned liquid containing the pulverized gel; or The method is to irradiate or heat the coating film after spraying the catalyst; or to irradiate or heat the coating film after spraying the catalyst or catalyst generating agent. For example, when the aforementioned catalyst is a photoactive catalyst, the aforementioned microporous particles can be chemically bonded to each other by light irradiation to form the aforementioned polysiloxane porous body. In addition, when the aforementioned catalyst is a thermally active catalyst, the aforementioned microporous particles can be chemically bonded to each other by heating to form the aforementioned polysiloxane porous body. The light irradiation amount (energy) of the aforementioned light irradiation is not particularly limited, and is, for example, 200-800 mJ/cm ² , 250-600 mJ/cm ² , or 300-400 mJ/cm ² in conversion of @360 nm. From the viewpoint of preventing the decomposition by the light absorption of the catalyst generating agent from progressing due to insufficient irradiation dose, the accumulated light dose is preferably 200 mJ/cm ² or more. In addition, from the viewpoint of preventing the substrate under the low-refractive index layer from being damaged and causing thermal wrinkles, the cumulative light intensity of 800 mJ/cm ² or less is suitable. The light wavelength of the aforementioned light irradiation is not particularly limited, for example, it is 200-500 nm, 300-450 nm. The light irradiation time of the aforementioned light irradiation is not particularly limited, and is, for example, 0.1 to 30 minutes, 0.2 to 10 minutes, or 0.3 to 3 minutes. The conditions of the aforementioned heat treatment are not particularly limited. The aforementioned heating temperature is, for example, 50~250°C, 60~150°C, 70~130°C, and the aforementioned heating time is, for example, 0.1~30 minutes, 0.2~10 minutes, 0.3~3 minutes. In addition, regarding the usable solvent, for example, when the purpose is to suppress the shrinkage stress caused by solvent volatilization during drying and the subsequent crack phenomenon of the low-refractive index layer, a solvent with low surface tension is preferable. Examples include lower alcohols represented by isopropanol (IPA), hexane, perfluorohexane, etc., but are not limited thereto.

The low-refractive-index layer (for example, polysiloxane porous body) of the present invention can be produced in the above-mentioned manner. However, the manufacturing method of the low refractive index layer of the present invention is not limited to the above. In addition, the low-refractive-index layer of this invention which is a polysiloxane porous body may be referred to as "the polysiloxane porous body of this invention" hereafter.

Also, as described above, in the production of the optical sheet for a light guide plate type liquid crystal display of the present invention, an adhesive layer may be further formed on the low refractive index layer of the present invention (adhesive layer forming step). Specifically, for example, an adhesive or an adhesive may be coated (coated) on the low refractive index layer of the present invention to form the aforementioned adhesive layer. Alternatively, the aforementioned adhesive layer side of an adhesive tape or the like on which the aforementioned adhesive layer is laminated can also be bonded to the low refractive index layer of the present invention, thereby forming the above-mentioned adhesive layer on the low refractive index layer of the present invention. Adhesive layer. At this time, the base materials such as the above-mentioned adhesive tape may be maintained in a directly bonded state, or may be peeled off from the above-mentioned adhesive layer. In particular, as described above, by peeling off the base material from the aforementioned low refractive index to create a base material-less (no base material), the thickness can be significantly reduced, and an increase in the thickness of devices and the like can be suppressed. In the present invention, "adhesive" and "adhesive layer" refer to a solvent or a layer that presupposes re-peeling of an adherend. In the present invention, "adhesive" and "adhesive layer" refer to a solvent or a layer that does not presuppose re-peeling of the adherend. However, in the present invention, "adhesive" and "adhesive" are not clearly distinguishable, nor are "adhesive layer" and "adhesive layer" clearly distinguishable. In the present invention, the adhesive or adhesive agent for forming the aforementioned adhesive layer is not particularly limited, and for example, general adhesive agents or adhesive agents can be used. The above-mentioned adhesive or adhesive agent can be, for example, polymer adhesives such as acrylic, vinyl alcohol, polysiloxane, polyester, polyurethane, and polyether, and rubber adhesives. In addition, adhesives etc. which consist of a water-soluble crosslinking agent of vinyl alcohol polymers, such as glutaraldehyde, melamine, and oxalic acid, etc. are mentioned. These adhesives and bonding agents may be used alone or in combination (for example, mixing, lamination, etc.). As mentioned above, the aforementioned low-refractive index layer can be protected from physical damage (especially scratches) by the aforementioned adhesive layer. In addition, the above-mentioned adhesive layer is preferably an optical sheet for a light guide plate type liquid crystal display without a base material (no base material), which is good in pressure resistance and does not crush the aforementioned low-refractive index layer, but it is not particularly limited. . Moreover, the thickness of the aforementioned adhesive layer is not particularly limited, for example, it is 0.1-100 μm, 5-50 μm, 10-30 μm or 12-25 μm.

The low-refractive index layer of the present invention obtained in the above manner can also be further laminated with the first optical film and the second optical film to produce the optical sheet for a light guide plate type liquid crystal display of the present invention. In this case, the low refractive index layer, the first optical film, and the second optical film may be laminated via the adhesive layer (adhesive or adhesive) as described above.

Based on the efficiency, the lamination of the above-mentioned components of the optical sheet for the light guide plate type liquid crystal display of the present invention, for example, can be carried out by continuous processing (so-called roll-to-roll (Roll to Roll) etc.) using a long film, When the base material is a molded object, a component, etc., it is also possible to laminate those that have been processed in batches.

The method for producing the optical sheet for the low refractive index layer and light guide plate type liquid crystal display of the present invention using the resin film substrate for transfer (hereinafter sometimes referred to simply as the "substrate") will be described with reference to Figs. 3 to 5 for example. In addition, the manufacturing method shown in figure is only an example, and is not limited to these.

The cross-sectional view in FIG. 3 schematically shows an example of the steps of manufacturing the optical sheet for a low-refractive index layer and a light guide plate type liquid crystal display of the present invention using the above-mentioned base material. In Fig. 3, the forming method of the aforementioned low refractive index layer comprises the following steps: coating step (1), coating the aforementioned liquid 20'' containing the pulverized gel of the present invention on the substrate 10; coating film forming step (drying) Step) (2), drying the liquid 20'' containing the pulverized gel to form a coating film 20', which is the precursor layer of the aforementioned low refractive index layer; and chemical treatment steps (such as cross-linking treatment Step) (3), performing chemical treatment (such as cross-linking treatment) on the coating film 20 ′ to form the low refractive index layer 20 . In this way, the low refractive index layer 20 can be formed using the substrate 10 as shown in the figure. In addition, the method for forming the aforementioned low-refractive index layer may suitably include steps other than the aforementioned steps (1) to (3), and there is no serious problem if it is not included. In addition, as shown in the figure, by carrying out the following steps, an optical sheet for a light guide plate type liquid crystal display including a laminate in which an adhesive layer 30 is directly laminated on one side or both sides of the low refractive index layer 20 can be manufactured. : adhesive layer coating step (4), coating the adhesive layer 30 on the surface of the low refractive index layer 20 opposite to the substrate 10; coating step (5), coating the adhesive layer 30 with an optical film 40; peeling off Step (6), peeling and removing the base material 10 from the low refractive index layer 20; the adhesive layer coating step (7), coating other adhesive layer on the surface of the low refractive index layer 20 on the side of the base material 10 that has been peeled off 30 ; and a coating step (8), coating the aforementioned other adhesive layer 30 with another optical film 40 . As for the two optical films 40, either one may correspond to the said 1st optical film, and the other may correspond to the said 2nd optical film. Also, the adhesive layer 30 to which the first optical film and the low-refractive index layer 20 are attached (adhered) can be regarded as the first adhesive layer. The adhesive layer 30 with the second optical film and the low-refractive index layer 20 attached (adhesively) can be regarded as the second adhesive layer. In addition, in Fig. 3, the method of separately carrying out the adhesive layer coating step (4) and the coating step (5) is shown, but the adhesive layer 30 (such as the optical film 40 and the adhesive tape 30 integrated) are attached to the low refractive index layer 20, so that the adhesive layer coating step (4) and coating step (5) are performed simultaneously. The same applies to the adhesive layer coating step (7) and the coating step (8). In addition, the aforementioned method of forming an optical sheet for a liquid crystal display in the form of a light guide plate may suitably include steps other than the aforementioned steps (1) to (8), and there is no serious problem if it is not included. For example, in FIG. 3 , a separator can also be attached instead of the optical film 40 to protect the adhesive layer 30 . For example, the aforementioned separator for protecting the adhesive layer 30 may also be peeled off, and the aforementioned first optical film or the aforementioned second optical film may be attached to the adhesive layer 30 to manufacture the optical sheet for a light guide plate type liquid crystal display of the present invention. material. And for example in Fig. 3, also can not use base material 10, and not on base material 10 but on the 1st optical film or the 2nd optical film 40, carry out aforementioned step (1)～(3) directly, form aforementioned low refractive index rate layer. At this time, the optical film 40 and the low-refractive-index layer 20 used to replace the base material 10 are directly laminated without interposing the adhesive layer 30 .

In the aforementioned coating step (1), the coating method of the liquid 20 ″ containing the pulverized gel is not particularly limited, and a general coating method can be used. The above-mentioned coating method can be, for example, a slot die coating (slot die) method, a reverse gravure coating (reverse gravure coat) method, a micro gravure (micro gravure) method (micro gravure coating (micro gravure coat) method), Dipping (Dip Coating), Spin Coating, Brush Coating, Roll Coating, Flexo Printing, Wire Bar Coating, Spray Coating, Extrusion Coating, Curtain Coating, Reverse coating method, etc. Among them, the extrusion coating method, the curtain coating method, the roll coating method, the micro gravure coating method and the like are preferable from the viewpoint of productivity and the smoothness of the coating film. The application amount of the gel pulverized product-containing liquid 20 ″ is not particularly limited, and can be appropriately set so that the porous structure (low refractive index layer) 20 has an appropriate thickness, for example. The thickness of the porous structure (low refractive index layer) 20 is not particularly limited, as described above.

In the aforementioned drying step (2), the liquid 20 ″ containing the pulverized gel is dried (that is, the dispersion medium contained in the liquid 20 ″ containing the pulverized gel is removed) to form a coating film (precursor layer) 20 ′ . The conditions of the drying treatment are not particularly limited, as described above.

In addition, in the aforementioned chemical treatment step (3), the coating film 20 containing the aforementioned catalyst (such as photoactive catalyst, photocatalyst generating agent, thermally active catalyst or thermal catalyst generating agent) added before coating 'Light irradiation or heating is performed to chemically bond the above-mentioned pulverized materials in the coating film (precursor) 20' (for example, to cross-link them) to form the low-refractive index layer 20. The light irradiation or heating conditions in the aforementioned chemical treatment step (3) are not particularly limited, as mentioned above.

Next, an example of the coating apparatus of the slit die coating method and the formation method of the said low-refractive-index layer using it is shown schematically in FIG. In addition, although FIG. 4 is a cross-sectional view, hatching is omitted for convenience of viewing.

As shown in the figure, each step of the method using the device is carried out while conveying the substrate 10 in one direction by means of rollers. The conveying speed is not particularly limited, and is, for example, 1 to 100 m/minute, 3 to 50 m/minute, or 5 to 30 m/minute.

First, the substrate 10 is delivered from the delivery roller 101 and conveyed at the same time. After the coating step (1) of coating the substrate with the gel pulverized product liquid 20 ″ of the present invention on the coating roller 102 , then in the oven zone Transition to drying step (2) in 110. In the coating device of Fig. 4, before entering the drying step (2) after the coating step (1), a pre-drying step is performed first. The pre-drying step does not require heating and can be performed at room temperature. The heating mechanism 111 is used in the drying step (2). As the heating mechanism 111, as described above, a heater, a heating roller, a far-infrared heater, or the like can be suitably used. Also, for example, the drying step (2) can be divided into several steps, and the closer to the subsequent drying step, the higher the drying temperature.

After the drying step (2), the chemical treatment step (3) is performed in the chemical treatment area 120 . In the chemical treatment step (3), for example, when the dried coating film 20' contains a photoactive catalyst, light is irradiated with lamps (light irradiation means) 121 arranged above and below the substrate 10. Or, for example, when the coating film 20' after drying contains a thermally active catalyst, a heater (heating mechanism) is used to replace the lamp (light irradiation device) 121, and the heater 121 disposed above and below the base material 10 will cover the base material. 10 heat. By this crosslinking treatment, the chemical bonding of the pulverized objects in the coating film 20' is induced, and the low refractive index layer 20 is hardened and strengthened. In addition, although illustration is omitted, the aforementioned steps (4) to (8) in FIG. 3 can be performed by a roll-to-roll (Roll to Roll) method to manufacture the aforementioned optical sheet for a light guide plate type liquid crystal display. Then, the prepared optical sheet for a light guide plate type liquid crystal display is wound up by a winding roll 105 .

FIG. 5 schematically shows an example of a coating apparatus of the microgravure method (microgravure coating method) and a method of forming the aforementioned porous structure using the same. In addition, although the same figure is a cross-sectional view, hatching is omitted for convenience.

As shown in the figure, each step of the method using this device is carried out while conveying the substrate 10 in one direction by the rollers, as in FIG. 4 . The conveying speed is not particularly limited, and is, for example, 1 to 100 m/minute, 3 to 50 m/minute, or 5 to 30 m/minute.

First, while conveying the substrate 10 from the delivery roller 201, the coating step (1) is performed, that is, the substrate 10 is coated with the liquid 20 ″ containing the pulverized gel material of the present invention. The coating of the liquid 20 ″ containing the pulverized gel is as shown in the figure, and is carried out by using a liquid storage area 202 , a doctor knife 203 and a micro-gravure plate 204 . Specifically, the liquid 20" containing pulverized gel stored in the liquid storage area 202 is attached to the surface of the micro-gravure plate 204, and then controlled to a predetermined thickness by the scraper 203 and coated on the substrate 10 with the micro-gravure plate 204 at the same time. Surface. In addition, the microgravure plate 204 is an example, and it is not limited thereto, and other arbitrary coating mechanisms may also be used.

Then the drying step (2) is carried out. Specifically, as shown in the figure, the substrate 10 that has been coated with the liquid 20" containing pulverized gel is transported in the oven area 210, and is heated and dried by the heating mechanism 211 in the oven area 210. The heating mechanism 211 can be combined with the Figure 4 is the same. Again, for example, the drying step (2) can also be divided into multiple steps by dividing the oven zone 210 into multiple blocks, so that the drying temperature becomes higher and higher along with the subsequent drying steps. In the drying step ( 2) Afterwards, the chemical treatment step (3) is carried out in the chemical treatment area 220. In the chemical treatment step (3), for example, when the dried coating film 20' contains a photoactive catalyst, it is arranged on the substrate 10 upper and lower lamps (light irradiation mechanism) 221 carry out light irradiation.Or, for example, when the coating film 20' after drying contains thermally active catalyst, can use heater (heating mechanism) to replace lamp (light irradiation device) 221 , the substrate 10 is heated with the air heater (heating mechanism) 221 arranged under the substrate 10. Through this crosslinking treatment, the chemical bonding of the above-mentioned pulverized objects in the coating film 20' is induced, and a low refractive index can be formed. Layer 20.

In addition, although illustration is omitted, the aforementioned steps (4) to (8) in FIG. 3 can be performed by a roll-to-roll (Roll to Roll) method to manufacture the aforementioned optical sheet for a light guide plate type liquid crystal display. Then, the prepared optical sheet for a light guide plate type liquid crystal display is wound up by a winding roll 251 .

[3. Void Layer] The case where the low refractive index layer of the present invention is a void layer (void layer of the present invention) will be described below with an example.

The void layer of the present invention may have, for example, a porosity of 35 volume % or more and a peak pore diameter of 50 nm or less. However, this is an example, and the void layer of the present invention is not limited thereto.

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

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

(Measurement method of porosity) If the layer to be measured for porosity is a single layer containing only voids, the ratio (volume ratio) of the constituent substances of the layer to air can be calculated by a normal method (such as measuring weight and volume to calculate density) Calculated, so the porosity (volume %) can be calculated by this. In addition, since the refractive index and the porosity have a correlation, for example, the porosity can be calculated from the value of the refractive index as a layer. Specifically, for example, the porosity can be calculated using Lorentz-Lorenz's formula from the value of the refractive index measured by an ellipsometer.

The interstitial layer of the present invention can be produced by chemical bonding of ground gelatin (microporous particles) as described above, for example. At this time, the voids in the void layer can be conveniently classified into the following three types (1) to (3). (1) Voids in the raw material gel itself (inside the particles) (2) Voids in the unit of the ground gel (3) Spaces between the grounds caused by the accumulation of ground gels

The voids in the aforementioned (2) may be formed when the particle groups generated by pulverizing the aforementioned gel are regarded as one mass (lump) regardless of the size and size of the gel pulverized matter (micropore particles). The void formed during crushing is inside each block and is different from the aforementioned (1). In addition, the voids in the above (3) are voids generated when the size, size, etc. of the gel pulverized matter (micropore particles) become uneven during pulverization (such as medialess pulverization, etc.). The void layer of the present invention, for example, has appropriate porosity and peak pore diameter due to the aforementioned voids (1) to (3).

In addition, the aforementioned peak pore diameter may be, for example, 5 nm or more, 10 nm or more, or 20 nm or more, or may be 50 nm or less, 40 nm or less, or 30 nm or less. In the void layer, if the peak pore diameter is too large in the state of high porosity, light will be scattered and become opaque. Also, 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 will be difficult to increase the porosity, so the peak pore diameter should not be too small. In the present invention, the peak pore diameter can be measured, for example, by the following method.

(Measurement method of peak pore diameter) Using a pore distribution/specific surface area measuring device (BELLSORP MINI/Trade name of Micromeritics Japan Co., Ltd.), BJH diagram, BET diagram and isotherm adsorption line were obtained by nitrogen adsorption and the results obtained therefrom Calculate the peak pore diameter.

Also, the thickness of the void layer in the present invention is not particularly limited, and may be, for example, 100 nm or more, 200 nm or more, or 300 nm or more, or may be 10000 nm or less, 5000 nm or less, or 2000 nm or less.

In addition, the void layer of the present invention, for example, has a scratch resistance of 60 to 100% obtained by using BEMCOT (registered trademark) that shows film strength, and a fold resistance of more than 100 times by using MIT test that shows flexibility, but is not limited to this.

The void layer of the present invention uses the pulverized product of the porous gel, so that the three-dimensional structure of the porous gel is destroyed, and a new three-dimensional structure different from the porous gel is formed. In this way, the void layer of the present invention can form a nanoscale layer with a high porosity by forming a layer having a new type of pore structure (new type of void structure) that cannot be obtained by the layer formed of the aforementioned porous gel. void layer. In addition, in the void layer of the present invention, for example, when the void layer is only a polysiloxane porous body, the pulverized materials can be chemically bonded to each other while adjusting the number of siloxane bond functional groups in the silicon compound gel, for example. In addition, after forming a new three-dimensional structure as the precursor of the aforementioned void layer, chemical bonding (such as cross-linking) will also be carried out in the bonding step, so the void layer of the present invention, for example, when the aforementioned void layer is a functional porous body, Although it is a structure with voids, it can still maintain sufficient strength and flexibility. Therefore, according to the present invention, it is possible to easily and simply provide a void layer to various objects.

The void layer of the present invention is, for example, the aforementioned pulverized product containing porous gel, and the aforementioned pulverized products are in a state of chemical bonding with each other. In the interstitial layer of the present invention, there is no particular limitation on the form of chemical bonding (chemical bond) between the above-mentioned pulverized objects, and specific examples of the above-mentioned chemical bonding include cross-linking bonds and the like. In addition, the method of chemically bonding the above-mentioned pulverized materials is as described in detail in the above-mentioned manufacturing method of the void layer.

The aforementioned crosslinks are, for example, siloxane bonds. Examples of the siloxane bond include T2 bond, T3 bond, and T4 bond shown below. When the polysiloxane porous body of the present invention has siloxane bonds, it may have, for example, any one of them, any two of them, or all three of them. Among the aforementioned siloxane bonds, the more the ratio of T2 and T3 is, the more flexible it is, and the more you can expect the original characteristics of the gel, but the film strength will be weaker. On the other hand, if the ratio of T4 in the above-mentioned siloxane bonds is too high, although it is easy to show the film strength, the void size will be smaller and the flexibility will be weaker. Therefore, for example, the ratios of T2, T3, and T4 should be adjusted according to the application.

[chemical formula 5]

When the gap layer of the present invention has the aforementioned siloxane bonds, the ratio of T2, T3 and T4 is, for example, when T2 is represented by "1", T2:T3:T4=1:[1~100]:[0~50] , 1: [1~80]: [1~40], 1: [5~60]: [1~30].

In addition, the interstitial layer of the present invention preferably contains silicon atoms that are bonded by siloxane, for example. As a specific example, the ratio of unbonded silicon atoms (that is, residual silanol) among the total silicon atoms contained in the polysiloxane porous body is, for example, less than 50%, less than 30%, and less than 15%.

The void layer of the present invention has a pore structure, and the pore size refers to the aforementioned major-axis diameter among the major-axis diameter and the minor-axis diameter of the void (pore). The pore size is, for example, 5 nm to 50 nm. Among the aforementioned void sizes, the lower limit is, for example, 5 nm or more, 10 nm or more, and 20 nm or more, and the upper limit is, for example, 50 nm or less, 40 nm or less, and 30 nm or less, and the range thereof is, for example, 5 nm to 50 nm or 10 nm to 40 nm. The void size is determined according to the application of the void structure, for example, it must be adjusted to a desired void size according to the purpose. The void size can be evaluated, for example, by the following method.

(Cross-section SEM observation of void layer) In the present invention, the form of the void layer can be observed and analyzed by SEM (scanning electron microscope). Specifically, for example, the aforementioned void layer can be subjected to FIB processing (accelerating voltage: 30kV) under cooling, and FIB-SEM (manufactured by FEI Corporation: trade name Helios NanoLab600, accelerating voltage: 1kV) can be used for the obtained cross-sectional sample to observe A cross-sectional electronic image was obtained at a magnification of 100,000 times.

(Evaluation of void size) In the present invention, the aforementioned void size can be quantified by BET test method. Specifically, after putting 0.1 g of the sample (the void layer of the present invention) into the capillary of a pore distribution/specific surface area measuring device (BELLSORP MINI/Micromeritics Japan company's trade name), the reduction was carried out at room temperature for 24 hours. Press dry to degas the gas in the void structure. Then, nitrogen gas is adsorbed on the above-mentioned sample, and the BET diagram and BJH diagram are drawn, and the adsorption isotherm is calculated to calculate the pore distribution. From this the void size can be assessed.

The void layer of the present invention has a scratch resistance of 60 to 100%, for example, obtained by using BEMCOT (registered trademark) which shows film strength. The present invention, for example, has excellent scratch resistance in various processes because of its strength. The present invention has resistance to injury in the production process such as winding up and handling the product film after the aforementioned void layer is produced. On the other hand, the void layer of the present invention, for example, is used instead of reducing the porosity, and can also use the catalytic reaction in the heating step described later to increase the particle size of the pulverized silicon compound gel and the combination of the pulverized products. The binding force of the neck. Thereby, the void layer of the present invention can impart a certain degree of strength to, for example, an inherently weak void structure.

The lower limit of the aforementioned scratch resistance is, for example, 60% or more, 80% or more, and 90% or more, and the upper limit is, for example, 100% or less, 99% or less, and 98% or less. The range is, for example, 60-100%, 80-99%, 90~98%.

The aforementioned scratch resistance can be measured, for example, by the following method.

(Evaluation of Scratch Resistance) (1) Sampling a circular object with a diameter of about 15 mm from the void layer coated and formed on the acrylic film (the void layer of the present invention). (2) Next, silicon was identified with fluorescent X-rays (manufactured by Shimadzu Corporation: ZSX Primus II) with respect to the above-mentioned samples to measure the Si coating amount (Si ₀ ). Then, the void layer on the acrylic film was cut into 50 mm x 100 mm from the sampled periphery, fixed to a glass plate (thickness 3 mm), and then subjected to a sliding test with BEMCOT (registered trademark). Sliding conditions were 10 reciprocations with a weight of 100 g. (3) Sampling and fluorescence X measurement were performed in the same manner as in (1) above from the void layer where sliding was completed, and the amount of remaining Si (Si ₁ ) after the scratch test was measured. Scratch resistance is defined by the remaining Si ratio (%) before and after the BEMCOT (registered trademark) test, and can be represented by the following formula. Scratch resistance (%)=[Residual Si amount (Si ₁ )/Si coating amount (Si ₀ )]×100(%)

The void layer of the present invention has a folding endurance of 100 or more times, for example, by using the MIT test showing flexibility. Since the present invention has such flexibility, handling properties such as winding up during manufacture and use are good.

The lower limit of the aforementioned folding times is, for example, more than 100 times, more than 500 times, and more than 1,000 times, and the upper limit is not particularly limited, such as less than 10,000 times, and its range is, for example, 100 to 10,000 times, 500 to 10,000 times, or 1,000 to 10,000 times .

The aforementioned flexibility refers to the easy deformability of a substance. The number of folding endurance obtained by the aforementioned MIT test can be measured, for example, by the following method.

(Evaluation of folding test) After cutting the aforementioned void layer (the void layer of the present invention) into a 20mm x 80mm short stick, install it on an MIT folding tester (manufactured by TESTER SANGYO CO,. LTD.: BE-202) And add a load of 1.0N. The collet that sandwiches the aforementioned void layer uses R2.0mm, and the maximum number of times of folding is 10,000, and the number of times when the aforementioned void layer breaks is taken as the number of folding endurance.

In the void layer of the present invention, the film density representing the porosity is not particularly limited, and its lower limit 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, and its upper limit is, for example, 50g/cm ³ or less, 40g/cm ³ or less, 30g/cm ³ or less, 2.1g/cm ³ or less, the range is, for example, 5~50g/cm ³ , 10~40g/cm ³ , 15~30g/cm ³ , 1~2.1g/cm ³ .

The aforementioned 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, the X-ray reflectance in the total reflection region was measured using an X-ray diffraction device (manufactured by RIGAKU: RINT-2000). After adjusting the Intensity and 2θ, calculate the porosity (P%) from the total reflection critical angle of the void layer and the substrate. The film density can be represented by the following formula. Membrane density (%)=100(%)-porosity (P%)

The void layer of the present invention is only required to have a pore structure (porous structure) as described above, and may be, for example, an open foam structure in which the pore structure is continuously formed. The aforementioned open foam structure means, for example, that the pore structure in the pore layer is connected in a three-dimensional manner, and it can also be said that the internal voids of the pore structure are connected together. When the porous body has an open foam structure, although it can increase the porosity in the whole, it cannot form openness when using closed-cell particles such as hollow silica. foam structure. On the other hand, since the void layer of the present invention has a three-dimensional dendritic structure of the sol particles (the pulverized product of the porous body gel forming the sol), in the coating film (sol-coated film containing the pulverized product of the aforementioned porous body gel), The open foam structure can be easily formed by the settlement and accumulation of the aforementioned dendritic particles. In addition, it is preferable that the interstitial layer of the present invention forms a monolithic structure with an open foam structure and a plurality of pores distributed therein. The aforementioned monolithic structure refers to, for example, a structure with nanometer-sized fine voids and a hierarchical structure in which an open foam structure formed by gathering the same nanoscale voids exists. When forming the above-mentioned monolithic structure, for example, fine voids provide film strength and coarse open foam voids provide high porosity, so that both film strength and high porosity can be achieved. To form these monolithic structures, it is important, for example, to firstly control the pore distribution of the generated void structure in the aforementioned porous body gel in the stage before pulverization into the aforementioned pulverized product. Also, for example, when pulverizing the porous gel, the monolithic structure can be formed by controlling the particle size distribution of the pulverized product to a desired size.

In the void layer of the present invention, the elongation at crack formation showing flexibility is not particularly limited, and its lower limit is, for example, 0.1%, 0.5%, or 1%, and its upper limit is, for example, 3% or less. The range of elongation at the formation of cracks above is, for example, 0.1-3%, 0.5-3%, 1-3%.

The aforementioned elongation at crack formation can be measured, for example, by the following method.

(Evaluation of crack formation elongation) After forming a void layer (void layer of the present invention) on the acrylic film, a short stick shape of 5 mm x 140 mm was sampled. Next, the sample was clamped by a tensile testing machine (manufactured by Shimadzu Corporation: AG-Xplus) so that the distance between grips was 100 mm, and then a tensile test was performed at a tensile speed of 0.1 mm/s. Carefully observe the aforementioned samples in the test, and end the test at the time point when cracks are formed on the part of the aforementioned sample, and use the elongation (%) at the time point when the cracks are formed as the crack formation elongation rate.

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

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

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

Generally speaking, the aforementioned refractive index is the ratio of the transmission speed of light on the wave front in vacuum to the propagation speed in the medium, which is called the refractive index of the medium. The refractive index of the polysiloxane porous body 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, and 1.15 or less, and its lower limit is, for example, 1.05 or more, 1.06 or more, and 1.07 or more. For example, it is 1.05 to 1.3, 1.05 to 1.3, 1.05 to 1.25, 1.06 to 1.2, 1.07 to 1.15.

In the present invention, the above-mentioned refractive index refers to the refractive index measured at a wavelength of 550 nm unless otherwise specified. Moreover, the measuring method of a refractive index is not specifically limited, For example, it can measure by the following method.

(Evaluation of Refractive Index) After forming a void layer (the void layer of the present invention) on the acrylic film, it was cut into a size of 50mm×50mm and attached to the surface of a glass plate (thickness: 3mm) with an adhesive layer. A sample that does not reflect on the back surface of the glass plate was prepared by blackening the center portion of the back surface of the glass plate (about 20 mm in diameter) with a black marker. The aforementioned sample was mounted on an ellipsometer (manufactured by J.A. Woollam Japan: VASE), and the refractive index was measured at a wavelength of 500 nm and an incident angle of 50 to 80 degrees, and the average value was used as the refractive index.

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

The form of the void layer in the present invention is not particularly limited, for example, it may be in the form of a thin film or a bulk.

The manufacturing method of the air gap layer of the present invention is not particularly limited, for example, it can be manufactured by using the above-mentioned manufacturing method of the aforementioned air gap layer. Example

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

[Reference Example 1] First, the gelation of the silicon compound (step (1) below) and the aging step (step (2) below) were performed to produce a gel (polysiloxane porous body) having a porous structure. Next, the following (3) morphology control step, (4) solvent replacement step, (5) concentration measurement (concentration management) and concentration adjustment step, (6) gel pulverization step are performed to obtain a low refractive index layer Coating liquid for formation (liquid containing pulverized gel). In addition, in this reference example, as described below, the following (3) form control step is performed in a different step from the following step (1). However, the present invention is not limited thereto. For example, the following (3) morphology control step can also be performed in the following step (1).

(1) Gelation of silicon compound Dissolve 9.5kg of MTMS which is the precursor of silicon compound in 22kg of DMSO. After adding 5 kg of 0.01 mol/L oxalic acid aqueous solution to the aforementioned mixture, it was stirred at room temperature for 120 minutes to hydrolyze MTMS to generate para(hydroxy)methylsilane.

After adding 3.8 kg of 28% ammonia water and 2 kg of pure water to 55 kg of DMSO, the aforementioned mixed solution subjected to hydrolysis treatment was further added, and stirred at room temperature for 60 minutes. Pour the liquid after stirring for 60 minutes into a stainless steel container of length 30cm×width 30cm×height 5cm and let it stand at room temperature, so as to gel the ginseng (hydroxy)methylsilane to obtain a gel-like silicon compound .

(2) Aging step The gel-like silicon compound obtained by the above-mentioned gelation treatment was incubated at 40°C for 20 hours to perform an aging treatment to obtain the aforementioned cuboid-shaped lump gel. Since the amount of DMSO (a high boiling point solvent with a boiling point of 130° C. or higher) used in the raw material accounts for about 83% by weight of the entire raw material, it can be seen that the gel contains more than 50% by weight of a high boiling point solvent with a boiling point of 130° C. or higher. Also, since the amount of MTMS (a monomer that is a gel constituting unit) used in the raw material accounts for about 8% by weight of the whole raw material, it can be seen that the hydrolysis of the gel constituting monomer (MTMS) in the gel The content of the generated solvent having a boiling point lower than 130° C. (methanol in this case) is 20% by weight or less.

(3) Morphological control step On the gel synthesized by the aforementioned steps (1) and (2) in the aforementioned 30cm x 30cm x 5cm stainless steel container, pour water to replace the solvent. Next, slowly insert the cutting knife of the jig for cutting into the gel in the aforementioned stainless steel container from above, and cut the gel into cuboids with a size of 1.5 cm x 2 cm x 5 cm.

(4) Solvent replacement step Next, the solvent replacement step was performed as described in (4-1) to (4-3) below.

(4-1) After the aforementioned "(3) Morphology Controlling Step", immerse the aforementioned gel-like silicon compound in water that is 8 times the weight of the aforementioned gel-like silicon compound, and slowly Stir for 1h. After 1h, exchange the water with the same amount of water, and stir for another 3h. Thereafter, the water was further exchanged again, and then stirred slowly at 60° C. while heating for 3 h.

(4-2) After (4-1), exchange the water with isopropanol which is 4 times the weight of the aforementioned gel-like silicon compound, and also stir and heat at 60°C for 6 hours.

(4-3) After (4-2), exchange isopropanol with isobutanol of the same weight, and heat at 60°C for 6 hours to replace the solvent contained in the aforementioned gel-like silicon compound with isobutanol alcohol. The gel for forming a void layer of the present invention was produced as described above.

(5) Concentration measurement (concentration management) and concentration adjustment steps After the solvent replacement step in (4) above, take out the bulk gel, and remove the solvent attached to the periphery of the gel. Then the concentration of solid components in a gel block is determined by gravimetric drying method. At this time, in order to obtain the reproducibility of the measured value, the measurement was performed with 6 blocks taken out at random, and the average value and the variation of the value were calculated. At this time, the average value of the concentration of the solid content in the gel (gel concentration) was 5.20% by weight, and the variation of the value of the aforementioned gel concentration among the 6 gels was within ±0.1%. Based on this measured value, an isobutanol solvent was added and adjusted so that the concentration of the gel solid content (gel concentration) would be about 3.0% by weight.

(6) Gel pulverization step For the aforementioned gel (gel-like silicon compound) after the concentration measurement (concentration management) and concentration adjustment steps of (5) above, the first pulverization step uses continuous emulsification and dispersion (Pacific Machine Works) Company-made, Milder MDN304 type), and the second pulverization stage was pulverized by two stages of high-pressure medialess pulverization (SUGINO MACHINE Ltd., Star Burst HJP-25005 type). The pulverization treatment is for 43.4 kg of the gel containing the above-mentioned gel-like silicon compound replaced by the solvent. After weighing and adding 26.6 kg of isobutanol, the first pulverization stage is carried out in a circular pulverization for 20 minutes, and the second pulverization stage is carried out. The crushing pressure is 100MPa. In this way, an isobutanol dispersion (liquid containing the ground gel) in which nano-sized particles (the ground gel) were dispersed was prepared.

Also, the solid content concentration (gel concentration) of the liquid (high-viscosity gel pulverization liquid) was measured after the first pulverization step (coarse pulverization step) and before the second pulverization step (nano pulverization step), and the result was 3.01% by weight was obtained. After the aforementioned first crushing stage (coarse crushing step) and before the aforementioned second crushing stage (nano crushing step), the volume average particle diameter of the crushed product of the aforementioned gel is 3-5 μm, and the shear viscosity of the aforementioned liquid is 4,000 mPa·s. At this time, the high-viscosity gel pulverization liquid has a high viscosity, so it can be processed into a uniform liquid without solid-liquid separation, so the measured value after the first pulverization stage (coarse pulverization step) can be directly used. In addition, after the second pulverization stage (nano pulverization step), the volume average particle diameter of the pulverized product of the gel is 250-350 nm, and the shear viscosity of the liquid is 5 m-10 mPa·s. Furthermore, after the second pulverization step (nano pulverization step), the solid content concentration (gel concentration) of the aforementioned liquid (liquid containing pulverized gel) was measured again. No change after the stage (coarse crushing step).

In addition, in this reference example, the average particle diameter of the pulverized product (sol particles) of the aforementioned gel after the aforementioned first pulverizing stage and after the aforementioned second pulverizing stage was determined by a dynamic light scattering Nanotrac particle size analyzer (Nikkiso Company system, brand name UPA-EX150 type)I confirm it. Also, in this example, the shear viscosity of the liquid after the first pulverization stage and after the second pulverization stage was confirmed with a vibrating viscometer (manufactured by Sekonic Co., trade name FEM-1000V). The same applies to the following Examples and Comparative Examples.

In addition, after the first pulverization step (coarse pulverization step), in the solid content (gel) of the liquid containing the pulverized gel, it is measured (calculated) that there are no functional groups (silanol groups) in the constituent unit monomers. The proportion of functional groups (residual silanol groups) contributing to the crosslinking structure in the gel resulted in a measured value of 11 mol%. In addition, the ratio of the functional groups (residual silanol groups) that do not contribute to the crosslinking structure in the gel is measured by the following method: after drying the gel, measure the solid state NMR (Si-NMR), and from the peak value of the NMR Calculate the ratio of residual silanol groups that do not contribute to the crosslinked structure.

The coating liquid (liquid containing pulverized gel) of this reference example (Reference Example 1) for forming a void layer was produced by the method described above. Also, the peak pore diameter of the ground gel (micropore particles) in the coating solution for forming a void layer (liquid containing the ground gel) was measured by the method described above, and found to be 12 nm.

[Example 1] A photobase generator (WPBG266 [trade name of Wako Pure Chemical Industries, Ltd.]: 1.5% concentration MIBK solution) was added to 3 g of the coating solution for forming a low-refractive index layer prepared in Reference Example 1. 0.36 g, bis(trimethoxysilyl)ethane (TCI) (5% concentration MIBK solution) 0.11g, and the gained liquid is coated on the resin film containing the alicyclic structure of 100 μm (Japan ZEON Co., Ltd., commodity Name "ZEONOR: ZF16 film") on the substrate (substrate film) and dried to form a low refractive index layer (refractive index: 1.18, porosity: 59% by volume) with a film thickness of about 800nm. Next, after UV irradiation (300 mJ) was performed from the low-refractive-index layer side, an adhesive (first adhesive layer) with a separator (75 μm) having a thickness of 12 μm was attached to the low-refractive-index layer. Then, the aforesaid alicyclic structure-containing resin film (substrate film) is peeled off from the integrated article of the aforesaid adhesive (adhesive layer) and low refractive index layer. Thereafter, another adhesive with a thickness of 5 μm (the second adhesive layer) is further pasted on the surface of the peeled base film to obtain a low-density film with a total thickness (overall thickness) of about 18 μm. Adhesive sheet for refractive index layer. In addition, the total thickness (overall thickness) refers to the total thickness of the laminate [excluding separators] of the aforementioned first adhesive layer, aforementioned low-refractive index layer, and aforementioned second adhesive layer. In each of the following examples and comparative examples Same. In the adhesive sheet containing the low refractive index layer, the ratio of the thickness of the adhesive (adhesive layer) (the total thickness of the aforementioned first adhesive layer and the aforementioned second adhesive layer) to the total thickness (overall thickness) The ratio is about 95%. Next, peel off the separator from the adhesive sheet containing the low-refractive index layer, and use the laminate of the first adhesive layer, the low-refractive index layer, and the second adhesive layer to place the backlight LED side-light type The light guide plate and the reflection plate of the liquid crystal display (light guide plate type LCD) were laminated and integrated to obtain the optical sheet for the light guide plate type liquid crystal display of this embodiment. Table 1 lists the evaluation results of the brightness characteristics of the optical sheet for liquid crystal displays of the light guide plate type.

[Example 2] Except that the aforementioned low-refractive index layer was formed by directly coating on the aforementioned reflective plate, the light guide plate of the backlight LED side-light liquid crystal display (light guide plate type LCD) was combined with the reflector in the same manner as in Example 1. Plates were integrated to produce an optical sheet for a light guide plate type liquid crystal display. That is, in the optical sheet for a light guide plate type liquid crystal display of this embodiment, there is no adhesive (adhesive layer) between the reflective plate and the low refractive index layer, and the reflective plate and the low refractive index layer are directly laminated. , other than that are the same as in Example 1. Table 1 lists the evaluation results of the brightness characteristics of the optical sheet for liquid crystal displays of the light guide plate type.

[Example 3] The aforementioned low-refractive index layer coating solution was replaced by adding a mixed photobase generator (WPBG266 [Wako Pure Chemical Industries, Ltd. trade name]: 1.5% to 3 g of the low-refractive index layer-forming coating solution) Concentration MIBK solution) 0.18g, bis(trimethoxysilyl) ethane (TCI) (5% concentration MIBK solution) 0.05g liquid, and form it to a refractive index of 1.14 (porosity: 61%), except Other than that, in the same manner as in Example 1, the light guide plate and the reflection plate of the backlight LED side-light liquid crystal display (light guide plate type LCD) were integrated to obtain an optical sheet for a light guide plate type liquid crystal display. Table 1 lists the evaluation results of the brightness characteristics of the optical sheet for liquid crystal displays of the light guide plate type.

[Example 4] The light guide plate of the light guide plate type optical sheet for liquid crystal displays of Example 1 was further separated by the first adhesive layer, the aforementioned low refractive index layer, and the aforementioned second adhesive layer in the same manner as in Example 1. The laminated body of the adhesive layer was bonded to the diffusion plate to obtain the optical sheet for the light guide plate type liquid crystal display (integrated sheet of reflective plate/light guide plate/diffusion plate) of this embodiment. Table 1 lists the evaluation results of the brightness characteristics of the optical sheet for liquid crystal displays of the light guide plate type.

[Example 5] An acrylic film with a thickness of 40 μm was used as the base film instead of the base film used in Example 1, and the base film was not peeled off, that is, on the side opposite to the aforementioned low refractive index layer of the base film. The above-mentioned adhesive (second adhesive layer) with a separator with a thickness of 5 μm was pasted on it, and in the same manner as in Example 1, the light guide plate of the backlight LED side-light liquid crystal display (light guide plate type LCD) was combined with the An optical sheet for a light guide plate type liquid crystal display was produced by integrating the reflecting plate. That is, the optical sheet for a light guide plate type liquid crystal display of this example has the aforementioned 40 μm thick acrylic film (substrate film) between the aforementioned low refractive index layer and the aforementioned second adhesive layer, and is similar to that of the embodiment except that Example 1 is the same. Table 1 lists the evaluation results of the brightness characteristics of the optical sheet for liquid crystal displays of the light guide plate type.

[Comparative Example 1] The light guide plate and the reflector plate of the backlight LED side-light liquid crystal display (light guide plate type LCD) are not sandwiched between the low refractive index layer and are only bonded with an adhesive with a thickness of 12 μm to integrate. An optical sheet for a liquid crystal display in the form of a light guide plate was prepared in the same manner as in Example 1. Table 1 lists the evaluation results of the brightness characteristics of the optical sheet for liquid crystal displays of the light guide plate type.

[Comparative Example 2] In the same manner as in Example 1, the light guide plate and the reflection plate of the backlight LED side-light liquid crystal display (light guide plate type LCD) were not integrated, and layers were laminated through air. That is, in this comparative example, no layers other than the air layer were disposed between the light guide plate and the reflection plate, and the low refractive index layer and the adhesive layer (adhesive) were not used. Table 1 shows the evaluation results of brightness characteristics and the like at this time.

[Table 1]

In addition, in Table 1, the luminance characteristics (uniformity of luminance) were measured as follows.

(Measurement method of luminance characteristics) For a TV set with an LED side-light backlight, use any one of the aforementioned embodiments or comparative examples to integrate the light guide plate and the sapphire sheet (however, in comparative example 2, it is separated Optical sheets for light guide plate type liquid crystal displays that are laminated with an air layer and not integrated) are used to make white displays on TVs, and then use the spectroradiometer SR-UL2 (product of TOPCON TECHNOHOUSE Co. Name) Each luminance of each coordinate is measured from the LED incident side of the light guide plate toward the terminal side.

As shown in Table 1, when the light guide plate and the reflection plate are integrated using the optical sheet for liquid crystal display of the light guide plate method of Examples 1 to 5, the light from the LED will propagate from the incident side of the light guide plate to the terminal side, and the luminance characteristics Good (uniform brightness). In addition, when the light guide plate and the reflector are integrated, foreign matter does not get mixed in, and the yield rate during the assembly process is also good.

On the other hand, in the comparative example, the light leaked before propagating to the terminal side of the light guide plate, and the result was that the light could not penetrate to the terminal side. That is, in Comparative Example 1, the light guide plate and the reflection plate were integrated only with an adhesive (adhesive layer) without using a low-refractive index layer, and the luminance was lower than that of Examples. In addition, in Comparative Example 2, the light guide plate and the reflection plate were not integrated, but the layers were laminated through the air. As a result, not only brightness unevenness (brightness unevenness) occurred, but also foreign matter was mixed in, and the yield during the assembly process was reduced.

In addition, in Example 5, the base film was assembled into the optical sheet for the light guide plate type liquid crystal display, but in other embodiments, the base film was not incorporated into the optical sheet for the light guide plate type liquid crystal display ( The base material) was manufactured, and the thickness of the optical sheet for light guide plate type liquid crystal displays was reduced. Industrial availability

As explained above, according to the present invention, an optical sheet for a light guide plate type liquid crystal display, a backlight unit for a light guide plate type liquid crystal display, and a light guide plate type liquid crystal display having a low refractive index layer having an extremely low refractive index can be provided.

10‧‧‧substrate 20‧‧‧low refractive index layer 20'‧‧‧coating film (precursor layer) 20''‧‧‧liquid containing ground gel 30‧‧‧adhesive layer (adhesive) 40 ‧‧‧optical film (first optical film or second optical film) 101‧‧‧delivery roller 102‧‧‧coating roller 105‧‧‧winding roller 110‧‧‧oven area 111‧‧‧heater (heating Mechanism) 120‧‧‧chemical treatment area 121‧‧‧lamp (light irradiation mechanism) or heater (heating mechanism) 201‧‧‧delivery roller 202‧‧‧liquid storage area 203‧‧‧scraper (doctor knife) 204‧ ‧‧Microgravure 210‧‧‧Oven area 211‧‧‧Heating mechanism 220‧‧‧Chemical treatment area 221‧‧‧Lamp (light irradiation mechanism) or heater (heating mechanism) 251‧‧‧Take-up roller 1000, 2000 , 6000‧‧‧Light guide plate method liquid crystal display (light guide plate method LCD) A1~A6, A12, A123‧‧‧Unit 1010‧‧‧Light guide plate (1st or 2nd optical film) 1020‧‧‧reflector plate (No. 1 or 2nd optical film) 1030‧‧‧稜菡 1040‧‧‧diffusion sheet (with diffuser) 1050‧‧‧brightness enhancement film 1060‧‧‧lower plate polarizer 1070‧‧‧adhesive (adhesive layer) 1080‧‧‧LCD panel 1090‧‧‧diffusion plate (1st or 2nd optical film)

1 is a cross-sectional view showing an example of the configuration of an optical sheet for a light guide plate type liquid crystal display, a backlight unit for a light guide plate type liquid crystal display, and a light guide plate type liquid crystal display of the present invention. 2 is a cross-sectional view showing another example of the configuration of the optical sheet for a light guide plate type liquid crystal display, the backlight unit for a light guide plate type liquid crystal display, and the light guide plate type liquid crystal display of the present invention. Fig. 3 is a cross-sectional view schematically showing an example of a method of manufacturing an optical sheet for a light guide plate type liquid crystal display of the present invention. Fig. 4 is a diagram schematically showing some steps of the method for producing an optical sheet for a light guide plate type liquid crystal display according to the present invention and an example of an apparatus used therefor. Fig. 5 is a diagram schematically showing some steps of the manufacturing method of the optical sheet for liquid crystal display of the light guide plate type according to the present invention and another example of the device used therefor. Fig. 6 is a cross-sectional view showing an example of a configuration of a light guide plate type liquid crystal display not having the optical sheet for a light guide plate type liquid crystal display of the present invention.

20‧‧‧Low refractive index layer

30‧‧‧adhesive layer (adhesive)

1000‧‧‧Light guide plate liquid crystal display (Light guide plate LCD)

Units A3~A6, A12‧‧‧

1010‧‧‧Light guide plate (1st or 2nd optical film)

1020‧‧‧reflector (1st or 2nd optical film)

1030‧‧‧稜珡

1040‧‧‧diffusion sheet (with diffuser sheet)

1050‧‧‧Brightness enhancement film

1060‧‧‧Lower plate polarizer

1070‧‧‧Adhesive (adhesive layer)

1080‧‧‧LCD panel

1090‧‧‧diffusion plate (1st or 2nd optical film)

Claims (7)

An optical sheet for a light guide plate type liquid crystal display, characterized in that: the first optical film, the first adhesive layer, the low refractive index layer, the second adhesive layer, and the second optical film are laminated in the aforementioned order, and the aforementioned low refractive index The refractive index of the layer is 1.25 or less, and at least one of the first optical film and the second optical film is a light guide plate, compared to the total of the first adhesive layer, the low refractive index layer, and the second adhesive layer Thickness, the total thickness of the first adhesive layer and the second adhesive layer is 85% or more. The optical sheet for a liquid crystal display in the form of a light guide plate according to claim 1, wherein the first optical film and the second optical film are respectively a polarizing plate for the lower plate, a brightening film, an embossed sheet, a diffuser plate, a light guide plate or a reflective plate, However, at least one of the first optical film and the second optical film is a light guide plate. The optical sheet for a light guide plate type liquid crystal display according to claim 1 or 2, wherein one of the first optical film and the second optical film is a light guide plate, and the other is an optical member other than the light guide plate. The optical sheet for a light guide plate type liquid crystal display according to claim 1 or 2, wherein the low refractive index layer is a void layer with a porosity of 35% by volume or more. A backlight unit for a light guide plate type liquid crystal display, comprising the light guide plate type liquid crystal display according to any one of claims 1 to 4 Academic sheet, side light and light guide plate. According to claim 5, the backlight unit for a light guide plate type liquid crystal display, wherein the side light is an LED side light. A liquid crystal display with a light guide plate, comprising the backlight unit for a liquid crystal display with a light guide plate according to claim 5 or 6.

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