TW201944147A - Optical sheet for liquid crystal display featuring light guide plate, backlight unit for liquid crystal display featuring light guide plate and liquid crystal display featuring light guide plate including a first optical film (light guide plate), a low refractive index layer and a second optical film (reflecting plate) - Google Patents

Abstract

The present invention provides an optical sheet for a liquid crystal display featuring a light guide plate having a low refractive index layer having an extremely low refractive index. The optical sheet for a liquid crystal display featuring a light guide plate of the present invention is characterized by having a first optical film (light guide plate), a low refractive index layer and a second optical film (reflecting plate) that are laminated in the above-described order. The refractive index of the low refractive index layer 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 with air therebetween. However, as devices become thinner, the integration of various components is expected. Therefore, the method of integrating each member with an adhesive without interposing an air layer is performed mostly (for example, patent document 1). However, once the air layer that does not have a total reflection function is used, oblique incident light will not be totally reflected and retroreflection cannot be used, which may reduce the light utilization efficiency.

Therefore, some literatures have proposed using 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 Literature Patent Literature Patent Literature 1: Japanese Patent Application Laid-Open No. 2012-156082 Patent Literature 2: Japanese Patent Application Laid-Open No. 10-62626

SUMMARY OF THE INVENTION Problems to be Solved by the Invention However, since the refractive index of the low-refractive index layer is much higher than that of the air layer, it is not possible to fully play the role of replacement of the air layer, and it is still impossible to avoid degradation of optical characteristics.

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

In order to achieve the foregoing 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 low refractive index layer is Below 1.25.

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

Advantageous Effects of Invention According to the present invention, it is possible 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.

Modes for Carrying Out the Invention The present invention will be described in more detail by way of examples. However, this invention is not limited at all 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 enhancing film, a cymbal, a diffusion plate, a light guide plate, or a reflecting 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 light guide plate may be, for example, a reflection plate, a diffusion plate, or a cymbal or a cymbal with a diffusion function.

The optical sheet for a light guide plate type liquid crystal display of the present invention may contain, for example, one or more of the first optical film and the second optical film other than the 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 through an adhesive layer. In addition, when the low refractive index layer and the first optical film are laminated with an adhesive layer interposed therebetween, the adhesive layer may be referred to as a "first adhesive layer" in some cases. In addition, when the low refractive index layer and the second optical film are laminated with an adhesive layer interposed therebetween, the adhesive layer may be referred to as a "second 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. In addition, for example, the 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 first adhesive layer and the second adhesive layer are thicker than 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 a laminate of the first adhesive layer, the low refractive index layer, and the second adhesive layer may be 80% or more. For example, the haze of the laminated body of the first adhesive layer, the low refractive index layer, and the second adhesive layer may be 3% or less. The light transmittance may be, for example, 82% or more, 84% or more, 86% or more, or 88% or more, and the upper limit is not particularly limited, and is preferably 100%, for example, 95% or less, 92% or less, 91% or less 90% or less. The haze measurement of the laminated body can be performed, for example, by the same method as the haze measurement of the low refractive index layer described later. The light transmittance is a light transmittance at a wavelength of 550 nm, and can be measured by, for example, the following measurement method.

(Measurement method of light transmittance) Using a spectrophotometer U-4100 (trade name of Hitachi, Ltd.), the adhesive sheet containing a low refractive index layer is not attached with a separator (the first adhesive layer, A laminate of the low refractive index layer and the second adhesive layer) was used as a sample to be measured. Next, the total light transmittance (light transmittance) of the aforementioned sample when the total light transmittance of air was 100% was measured. The value of the 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, the manufacturing method may include the following steps: a low-refractive-index layer forming step to form the aforementioned low-refractive index on a resin film substrate for transfer Rate layer; and a transfer step, transferring the aforementioned low refractive index layer onto the aforementioned adhesive layer. In addition, this manufacturing method may be called "the manufacturing method of the optical sheet for 1st light-guide plate-type liquid crystal display" hereafter. In addition, a thing with a small thickness is sometimes referred to as a "film" and a thing with a large thickness is sometimes referred to as a "sheet", but in the present invention, the "film" and the "sheet" are not particularly distinguished.

The method for manufacturing an optical sheet for a liquid crystal display device of the first light guide plate method of the present invention may further include a step of attaching a separator, for example, adding the foregoing to the side of the adhesive layer opposite to the low refractive index layer. Separate pieces.

The first method for producing an optical sheet for a liquid crystal display of the light guide plate method of the present invention may further include a step of peeling off a resin film substrate for transfer, which is a step of attaching the resin for transfer after the step of attaching the separator The film substrate is peeled. In this case, the peeling force between the separator and the adhesive layer should be greater than the peeling force between the transfer resin film substrate and the low refractive index layer. For another example, it is possible to further include a step of peeling off the separator and a step of attaching an optical film, the former is to peel the separator from the adhesive layer, and the latter is to attach the first optical film or the second optical film to The aforementioned adhesive layer. 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 method for producing an optical sheet for a liquid crystal display device of the first light guide plate method of the present invention, for example, the resin film substrate for transfer may be formed of an alicyclic structure resin or an aliphatic structure resin. From the viewpoint of durability such as heat drying when the low refractive index layer is formed, an alicyclic structure resin having excellent heat resistance is particularly expected. The aforementioned aliphatic structure-containing resin is not particularly limited, and examples thereof include polyolefin, polypropylene, and polymethylpentene. The aforementioned alicyclic structure-containing resin is not particularly limited, and examples thereof include polynorbornene and a cyclic olefin copolymer.

In addition, the method for manufacturing an optical sheet for a light guide plate type liquid crystal display of the present invention may also be a manufacturing method including the following steps: a coating step of directly coating the raw material of the low refractive index layer on the adhesive layer; And a drying step of drying the coating liquid. In addition, this manufacturing method may be called "the manufacturing method of the optical sheet for 2nd light-guide plate-type liquid crystal display" hereafter.

In addition, the method for manufacturing an optical sheet for a light guide plate type liquid crystal display of the present invention may also be a manufacturing method including the following steps: a coating step in which the aforementioned low optical layer is directly coated on the first optical film or the second optical film. A coating liquid for the raw material of the refractive index layer; and a drying step of drying the coating liquid. In addition, this manufacturing method may be called "the manufacturing method of the optical sheet for 3rd light guide plate type liquid crystal display" hereafter. In addition, below, the manufacturing method of the optical sheet for 1st, 2nd, and 3rd light guide plate type liquid crystal displays of this invention may be collectively called "the manufacturing method of the optical sheet for light guide plate type liquid crystal displays of this invention."

In a light guide plate type liquid crystal display (hereinafter sometimes referred to as a “light guide plate type LCD”), for example, an LED light guide plate type LCD using an LED (light emitting diode) as a backlight (side light) is used. For example, each optical film closer to the backlight side than the polarizer of the lower plate of the light guide plate LCD can be laminated with air through the air layer. The air layer will be incident at an angle above a certain degree optically. The effect of light reflection. In the LED light guide plate type LCD, for example, a reflective plate, a light guide plate (including LED), a diffusion plate, a cymbal, a diffuser with a diffuser, a brightness enhancement film (reflective polarizing film), and a lower polarizer can be sequentially laminated.

However, when the above-mentioned air layer is present, for example, the optical film may be deflected due to the enlargement of the LCD, which may cause degradation of optical characteristics. In addition, for example, foreign matter may enter the air layer, thereby reducing the yield of the light guide plate type LCD during the assembly step. Therefore, in order to solve these problems, it is conceivable to attempt to integrate the optical films without using an air layer and reduce the number of optical films required for the lamination during the assembly step. However, if the adhesive is used for integration at that time, there may not be an air layer that exerts the function of total reflection, and as described above, the incident light that becomes oblique angle cannot be totally reflected and the retroreflection cannot be used. Furthermore, this may reduce the efficiency of light utilization.

On the other hand, in order to solve the aforementioned problems, it is also conceivable to insert a low refractive index layer instead of the air layer. However, as mentioned above, the refractive index of the conventional low-refractive-index layer is much higher than that of the air layer, so the substitute function of the air layer cannot be fully exerted, and the degradation of optical characteristics cannot be avoided. In contrast, the low-refractive index layer of the optical sheet for a light guide plate type liquid crystal display of the present invention has an extremely low refractive index of 1.25 or less, and thus can exhibit good optical characteristics.

According to the optical sheet for a light guide plate type liquid crystal display of the present invention, for example, the optical film on the backlight side can be integrated more than the polarizer plate on the lower plate of the LED light guide plate type LCD. For another example, by using the present invention to integrate the optical films of the LED light guide plate type LCD (such as the light guide plate and the reflection plate or the light guide plate, the reflection plate and the diffusion plate), the number of components during the LCD assembly step can be reduced, so Reduce the chance of foreign matter mixing into components, and improve assembly yield. For another example, it is possible to eliminate the decrease in optical characteristics (such as uneven brightness) caused by the deflection when an optical film (such as a reflective plate) is installed on a member as the LCD is enlarged.

In addition, if you want to use the low refractive index layer directly on the substrate, 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 LCD for use The thickness of the light guide plate LCD itself will also increase. On the other hand, for example, since the optical sheet for a light guide plate type liquid crystal display of the present invention does not include a substrate, it can be made thin. Specifically, for example, there is almost no increase in thickness other than the thickness of the adhesive layer itself without the base material, 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 to this. For example, the optical sheet for a light guide plate type liquid crystal display of the present invention may include a substrate.

As mentioned above, the optical sheet for a light guide plate type liquid crystal display of the present invention may be, for example, a laminate of the low refractive index layer, the first optical film, and the second optical film via an adhesive layer. Thereby, the adhesive layer can substantially enhance the strength of the low refractive index layer and protect it from physical damage. Therefore, it is possible to prevent the brittleness of the low refractive index layer from becoming a fatal problem. Specifically, the physical damage described above, for example, when the optical films are integrated by using a low refractive index layer, the strength of the low refractive index layer may be insufficient, and the low refractive index may be caused by the difference in the thermal expansion coefficients of the optical films. The rate layer cannot withstand the strain between the optical films. By using the adhesive layer, the low refractive index layer can be protected from the strain between the optical films. For another example, the abrasion resistance of the low-refractive index layer can be compensated by the adhesive layer, and the low-refractive index layer can be protected from abrasion. In addition, the optical sheet for a light guide plate type liquid crystal display of the present invention can be attached to other members by the aforementioned adhesive layer, so it is easy to introduce the 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, a thin layer and a low refractive index layer can be physically protected while maintaining a low refractive index layer having a high porosity. While maintaining high transparency, it is easy to introduce the function of a low-refractive-index layer into other light guide plate LCDs.

[1. Light guide plate type liquid crystal display optical sheet, light guide plate type liquid crystal display backlight unit and light guide plate type liquid crystal display] The following uses FIGS. 1, 2 and 6 to illustrate the light guide plate type liquid crystal display optical sheet of the present invention by way of example. Material, the structure of a light guide plate type liquid crystal display backlight unit and a light guide plate type liquid crystal display. In addition, although FIGS. 1, 2 and 6 are sectional views, hatching is omitted for the sake of simplicity.

First, an example of the configuration of a light guide plate type liquid crystal display (light guide plate type LCD) without using a low refractive index layer is shown in the cross-sectional view of FIG. 6. As shown in the figure, the LCD6000 series units A1 to A6 of the light guide plate method are formed by laminating in the above order. The unit A1 is composed of a reflection plate 1020. The unit A2 is composed of a light guide plate 1010. The light guide plate 1010 has side light. The unit A3 is composed of a diffusion plate 1090. The unit A4 series cymbal 1030 and the diffusion sheet (the cymbal with a diffusion sheet) 1040 are composed of laminated layers in the aforementioned order. The unit A5 is composed of a brightness enhancement film 1050. The unit A6 series lower plate polarizing plate 1060, the adhesive (adhesive layer) 1070, and the liquid crystal panel 1080 are formed by laminating layers in the aforementioned order. In addition, air layers are arranged between the units A1 and A2 and between the units A2 and A3, respectively.

An 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 in FIG. 1. As shown in the figure, the light guide plate type LCD1000 series unit A1 and unit A2 are integrated through the adhesive layer and the low refractive index layer to form a unit A12, except that it is the same as the light guide plate type LCD6000 in FIG. 6. More specifically, the light guide plate type LCD 1000 has a laminated body of the low refractive index layer 20 and the adhesive layer 30 between the units A1 and A2 instead of the air layer. The laminated body is directly laminated with an adhesive layer 30 on both sides of the low refractive index layer 20 respectively. The reflective plate 1020 of the unit A1 and the light guide plate 1010 of the unit A2 respectively pass through the adhesive layer 30 and are then (adhered) to the low refractive index layer 20. As described above, unit A1 and unit A2 are thereby integrated to form unit A12. The refractive index of the low refractive index layer 20 is 1.25 or less. The unit A12 corresponds to an optical sheet for a light guide plate type liquid crystal display of the present invention. One of the light guide plate 1010 and the reflection plate 1020 can be regarded as the aforementioned first optical film and the other as the aforementioned second optical film. 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, the unit A12 also corresponds to the backlight unit for a light guide plate type liquid crystal display of the present invention.

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

In addition, since the light guide plate type LCD 1000 of FIG. 1 does not have a base material for fixing the low refractive index layer 20, the low refractive index layer 20 can be introduced without increasing the thickness from the base material. This makes it possible to reduce the thickness of the light guide plate type LCD.

In addition, the LCD 1000 of the light guide plate method of FIG. 1 has an adhesive layer 30 on both areas 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 strain due to the difference in thermal expansion coefficients of the light guide plate 1010 and the reflective plate 1020. In addition, during the operation 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 of FIG. 1 does not have an air layer between the light guide plate 1010 and the reflection plate 1020, so the chance of foreign objects being mixed between the light guide plate 1010 and the reflection plate 1020 can be reduced, and the assembly yield can be improved.

In addition, the sectional view of FIG. 2 shows another example of the configuration of the light guide plate type liquid crystal display (light guide plate type LCD) of the present invention. As shown in the figure, the unit A12 and unit A3 of the light guide plate method LCD2000 are integrated through the adhesive layer and the low refractive index layer to form unit A123, except that the unit A123 is the same as the light guide plate type LCD1000 of FIG. 1. More specifically, the light guide plate LCD2000 has a laminated body of the low refractive index layer 20 and the adhesive layer 30 between the units A12 and A3 instead of the air layer. The laminated body is directly laminated with an adhesive layer 30 on both sides of the low refractive index layer 20 respectively. The light guide plate 1010 of the unit A12 and the diffusion plate 1090 of the unit A3 respectively pass through the adhesive layer 30 and are then (adhered) on the low refractive index layer 20. As described above, the unit A12 and the unit A3 are integrated to form the unit A123. The refractive index of the low refractive index layer 20 is 1.25 or less. The unit A123 corresponds to an optical sheet for a light guide plate type liquid crystal display of the present invention. One of the light guide plate 1010 and the diffusion plate 1090 may be regarded as the aforementioned first optical film, and the other as the aforementioned second optical film. In addition, similarly to the light guide plate type LCD 1000 in FIG. 1, either of the light guide plate 1010 and the reflection plate 1020 can be regarded as the aforementioned first optical film and the other as the aforementioned second optical film. The unit A123 is an optical sheet for a light guide plate type liquid crystal display, includes a light guide plate 1010, and the light guide plate 1010 has side light as described above. Therefore, the unit A123 also corresponds to the backlight unit for a light guide plate type liquid crystal display of the present invention.

The light guide plate method LCD2000 of FIG. 2 can exert the same advantages as the light guide plate method LCD1000 of FIG. 1 through the light guide plate 1010 and the reflection plate 1020 respectively through the adhesive layer 30 and then (adhesive) to the low refractive index layer 20 effect. In the light guide plate LCD2000 of FIG. 2, the light guide plate 1010 and the diffuser plate 1090 pass through the adhesive layer 30 and are then adhered (adhered) to the low-refractive index layer 20 to further exert the same advantageous effects as described above.

[2. Optical sheet for light guide plate type liquid crystal display and manufacturing method thereof] The manufacturing method of the optical sheet for light guide plate type liquid crystal display of the present invention is not particularly limited, and it can be performed by, for example, the following method: Method for producing optical sheet for first light guide plate type liquid crystal display, method for producing optical sheet for second light guide plate type liquid crystal display of the present invention, or optical sheet for third light guide plate type liquid crystal display of the present invention (A method for producing an optical sheet for a light guide plate type liquid crystal display of the present invention). Here are some examples. In addition, 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" hereafter. 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 manufacturing method thereof] The low-refractive index layer of the present invention may be formed of, for example, a silicon compound. The low-refractive index layer of the present invention may be, for example, a low-refractive index layer formed by chemically bonding fine-pored particles to each other. For example, the fine-pored particles may be a pulverized product of a gel.

In the method for producing a low-refractive index layer according to the present invention, for example, the gel pulverization step for pulverizing the gel of the porous body may be one step, but it is preferably performed by dividing into a plurality of pulverization steps. The number of the pulverization stages is not particularly limited, and may be, for example, two stages or 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 pulverizing the gel. A stage in which particles having a volume average particle diameter of 0.5 to 100 μm are made, and the second pulverization stage is a stage in which the particles are further pulverized into particles having a volume average particle diameter of 10 to 1000 nm after the first pulverization stage. 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 the "particles" (such as particles of the pulverized product of the gel) is not particularly limited, and may be, for example, a spherical or non-spherical system. Furthermore, in the present invention, the particles of the pulverized material may be, for example, sol-gel beaded particles, nano particles (hollow nano silica, nano ball particles), nano fibers, and the like.

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

In the present invention, the pulverized gel may have a structure having at least one of a granular shape, a fibrous shape, and a flat shape. The granular and flat structural units may be made of, for example, an inorganic substance. The constituent elements of the granular constituent unit may include, for example, at least one element selected from the group consisting of Si, Mg, Al, Ti, Zn, and Zr. The granular structure (constituting unit) can be solid particles or hollow particles. Specific examples include polysilicon particles or polysilicon particles with fine pores, hollow silica particles, or hollow silica particles. Nano ball and so on. The fibrous structural unit is, for example, a nanofiber having a nanometer diameter, and specific examples thereof include a cellulose nanofiber and an alumina nanofiber. Examples of the flat-shaped constituent unit are nanoclay, and specifically, nano-sized bentonite (for example, Kunipia F [trade name]) and the like are mentioned. The aforementioned fibrous constituent unit is not particularly limited, and may be, for example, at least one fibrous substance selected from the group consisting of carbon nanofiber, cellulose nanofiber, alumina nanofiber, and chitin. Quality nanofiber, chitosan nanofiber, polymer nanofiber, glass nanofiber and silicon dioxide nanofiber.

In the method for manufacturing a low-refractive index layer of the present invention, the gel pulverization step (for example, the plurality of pulverization stages, such as the first pulverization stage and the second pulverization stage) may be included in the "other solvent", for example. get on. In addition, the details of the aforementioned "other solvents" will be described later.

In the present invention, the "solvent" (for example, a solvent for producing a gel, a solvent for producing a low-refractive index layer, a solvent for replacement, etc.) may be used without dissolving the gel or its pulverized matter. For example, the aforementioned gel or The pulverized material and the like are dispersed or precipitated in the aforementioned solvent.

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

In addition, the shear viscosity of the liquid at the present time after the first pulverization step may be 50 mPa / s or higher, 1000 mPa · s or higher, 2000 mPa · s or higher, or 3000 mPa · s or higher at a shear rate of 10001 / s, and may 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 pulverization 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. . The method for measuring the shear viscosity is not particularly limited. For example, it can be measured using a vibration viscosity measuring machine (manufactured by Sekonic Co., trade name: FEM-1000V) as described in Examples described later.

After the first pulverization step, 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 manufacturing method of the low-refractive-index layer of the present invention includes, for example, a concentration adjustment step after the aforementioned solvent replacement step and before the beginning of the initial pulverization phase, but it does not need to include the concentration adjustment step. concentration. When the concentration adjustment step is included, it is not appropriate to adjust the concentration of the liquid containing the gel, for example, after the start of the first pulverization stage.

In the foregoing concentration adjustment step, the gel concentration of the liquid containing the porous body gel may 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 2.8% by weight or more, and It can be adjusted to, for example, 5 wt% or less, 4.5 wt% or less, 4.0 wt% or less, 3.8 wt% or less, or 3.4 wt% or less. In the foregoing concentration adjustment step, the gel concentration of the liquid containing the gel can be adjusted to, for example, 1 to 5 wt%, 1.5 to 4.0 wt%, 2.0 to 3.8 wt%, or 2.8 to 3.4 wt%. From the viewpoint of easy handling in the gel pulverization step, in order not to make the viscosity too high, the aforementioned gel concentration should not be too high. In addition, from the viewpoint of use as a coating solution to be described later, in order to prevent the viscosity from becoming too low, the gel concentration should not be 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 component (gel) after removing the solvent of the liquid, and then dividing the measured value of the latter by the measured value of the former.

In addition, the concentration adjustment step may, for example, appropriately adjust the gel concentration of the liquid containing the gel, or may increase the concentration by adding a solvent to reduce the concentration or evaporating the solvent. Or, for example, in the aforementioned concentration adjustment step, if the gel concentration of the liquid containing the aforementioned gel is measured, the gel concentration is appropriate, and the liquid containing the aforementioned gel can be directly used 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 gel is clearly known to be appropriate without measurement, and the liquid containing the gel may be directly supplied to the liquid without the measurement and concentration adjustment. The next step.

In the aforementioned gel pulverization step, the weight% concentration change of the liquid containing the gel may be, for example, within ± 3%, ± 2.8, from the time before the initial pulverization phase begins to immediately after the end of the final pulverization phase. Within%, within ± 2.6%, within ± 2.4%, or within ± 2.2%.

In the method for manufacturing a low-refractive index layer of the present invention, it is preferable that a gel morphology control step is further included before the solvent replacement step, which controls the shape and size of the gel. In the aforementioned gel morphology controlling step, it is desirable to control 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, it is possible to easily prevent the measured value of the solvent concentration from being lower than the actual concentration and the solvent remaining by attaching a large amount of solvent around the finely pulverized gel. Problems such as high actual concentration or further variation in measurement. It is also because the solvent replacement efficiency is good as long as the size of the gel is not too large before the aforementioned solvent replacement step. In addition, after the gel morphology control step, it is desirable to perform control so that the sizes of the gels are almost uniform. This is because as long as the size of each gel is almost uniform, it is possible to suppress variations in the particle size and gel concentration of the pulverized gel between the lots containing the pulverized gel liquid, and to easily obtain uniformity. Best gel-containing liquid.

In the gel shape control step, the short diameter of the 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 be controlled to be 15 cm or less, 13 cm or less, and 10 cm or less. Or below 8cm. In the gel shape control step, the length of the gel may be controlled to be, for example, 30 cm or less, less than 30 cm, 28 cm or less, 25 cm or less, or 20 cm or less, and may be controlled to be 1 cm or more, 2 cm or more, and 3 cm, for example. Above, above 4cm or above 5cm. In the present invention, the "short diameter" of a three-dimensional body (three-dimensional body) refers to a length measured at a portion where the length of the three-dimensional body can be measured and where the length becomes the shortest. Further, in the present invention, the "long diameter" of a three-dimensional body (three-dimensional body) refers to a length measured at a portion where the length of the three-dimensional body can be measured and where the length becomes the longest.

The shape of the gel after the gel shape control step is not particularly limited, such as controlling a growing cube (including a cube), a cylinder, a polygonal cube (such as a polygonal column such as a triangular column, a hexagonal column), a spherical shape, or an oval ball (Such as the shape of a football). After the gel morphology control step, controlling the shape of the gel to a rectangular parallelepiped or an almost rectangular parallelepiped is simple and desirable. In the gel shape control step, when the gel is controlled to grow into a rectangular parallelepiped, 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 15 cm or less 13 cm or less, 10 cm or less, or 8 cm or less. In the gel shape control step, when the gel is controlled into a rectangular parallelepiped, the long side may be controlled to be, for example, 30 cm or less, less than 30 cm, 28 cm or less, 25 cm or less, or 20 cm or less, and may be controlled to be 1 cm or more. , 2cm or more, 3cm or more, 4cm or more, or 5cm or more. In the present invention, the "short side" of the cuboid refers to the shortest side, and the "long side" refers to the longest side.

The gel morphology controlling step may be performed, for example, after the gel producing step for producing the gel, or may be performed during the gel producing step (same time as the gel producing step). More specifically, it is as follows.

In the gel shape control step, for example, the gel can be cut in a state where the gel is fixed, so as to control the gel into the solid. In the case where the brittleness of the gel is extremely high, there is a possibility that the gel may be unevenly cracked regardless of the cutting direction when the gel is cut. Therefore, by fixing the gel around, the pressure in the compression direction applied during cutting can be uniformly applied to the gel itself, so the gel can be uniformly cut along the cutting direction. For example, the shape of the gel before the solvent replacement step is almost a rectangular parallelepiped. In the gel shape control step, 5 of the 6 faces of the almost rectangular parallelepiped gel surface may be in phase with other substances. The gel was fixed by contact, and a cutting jig was inserted from the exposed surface to the gel with the other surface exposed to cut the gel. The cutting jig is not particularly limited, and examples thereof include a cutter, a wire-like thin strip-shaped jig, and a thin and sharp plate-like jig. The cutting of the gel may be performed in the other solvent, for example.

For another example, in the gel manufacturing step, the raw material of the gel may be cured in a template (container) corresponding to the shape and size of the three-dimensional body, thereby controlling the gel to the three-dimensional body. With this, even if the gel is extremely brittle, the gel can be controlled to a predetermined shape and size without cutting the gel. Therefore, when the gel is cut, the gel can be prevented from occurring regardless of the cutting direction. Case of uneven collapse.

In the method for producing a low-refractive index layer of the present invention, for example, the gel concentration of the gel-containing liquid (gel-containing liquid) may be measured after the end of the first pulverization stage and before the end of the final pulverization stage. And only the aforementioned liquid having the aforementioned gel concentration within a predetermined numerical range is supplied to the subsequent pulverization stage. In addition, it is necessary to be a homogeneous liquid when measuring the gel concentration. Therefore, after the above-mentioned pulverization stage is completed, it should be a liquid with a certain degree of high viscosity and less prone to solid-liquid separation. As mentioned above, if from the viewpoint of easy handling of the gel-containing liquid, the gel concentration should not be too high in order not to make the viscosity too high; from the viewpoint 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 consistently supply only the liquid having the aforementioned gel concentration within a predetermined numerical range until the end of the final pulverization stage. The predetermined numerical range of the aforementioned gel concentration is as described above, for example, it may be 2.8% by weight or more and 3.4% by weight or less, but is not limited thereto. As described above, the gel concentration measurement (concentration management) may be performed after the end of the first pulverization stage and before the end of the last pulverization stage, but may also be performed after the solvent replacement step and before the gel pulverization step and the final One or both of the pulverization stages (for example, the aforementioned second pulverization stage) are performed, or they may be simply replaced. After the gel concentration is measured, for example, only the liquid having the gel concentration within a predetermined numerical range is supplied to a subsequent pulverization stage, or a gel-containing pulverized product-containing liquid is provided as a finished product. 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, since the concentration management after the solvent replacement step and before the gel pulverization step is not stable due to the amount of the solvent attached to the gel, there may be a large variation in each measurement of the concentration measurement value. Therefore, it is preferable to control the shape and size of the gel to be almost uniform by the aforementioned gel morphology control step after the solvent replacement step and before the concentration management before the gel pulverization step. Thereby, the concentration can be measured stably. In addition, for example, the gel concentration of the gel-containing liquid can be managed individually and accurately.

In the method for manufacturing a low-refractive index layer of the present invention, it is preferred that at least one of the plurality of pulverization stages is different from at least one other pulverization stage in a pulverization manner. The pulverization methods of the plurality of pulverization steps may all be different from each other, or may be pulverization steps performed by the same pulverization method. For example, when the above-mentioned multiple crushing stages are three stages, all three stages can be performed in different ways (that is, using three crushing ways), or any two of the crushing stages can be performed in the same crushing way, and only other One crushing stage is performed in different crushing methods. The pulverization method is not particularly limited, and examples thereof include a cavitation method and a medialess method described later.

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

In the method for manufacturing a low-refractive index layer of the present invention, the plurality of pulverization stages may include a coarse pulverization stage and a formal pulverization stage. After obtaining massive sol particles through the coarse pulverization stage, the formal pulverization stage is used to obtain and maintain porosity. Sol particles in the gel-like network.

The method for producing a low-refractive index layer of the present invention includes, for example, after at least one of the pulverization stages of the plurality of stages (for example, at least one of the first pulverization stage and the second pulverization stage), further comprising: The particles are subjected to a classification step.

The method for producing a low-refractive index layer of the present invention includes, for example, a gelation step, which is performed by gelatinizing a bulk porous body in a solvent to form the aforementioned gel. At this time, for example, in the first pulverization stage (for example, the first pulverization stage) among the pulverization stages of the plurality of stages, the gel that is gelled by the gelation step is used.

The method for producing a low-refractive index layer according to the present invention includes, for example, a aging step, in which the gelatinized gel is cured in a solvent. At this time, for example, in the first pulverization stage (for example, the first pulverization stage) among the pulverization stages of the plurality of stages, the gel after the maturation step is used.

For example, in the method for producing a low-refractive index layer of the present invention, the solvent replacement step is performed after the gelation step, that is, the solvent is replaced with another solvent. At this time, for example, in the first pulverization stage (for example, the first pulverization stage) among the pulverization stages of the plurality of stages, the gel in the other solvent is used.

In the method for producing a low-refractive index layer of the present invention, at least one of the aforementioned multi-stage pulverization stages (for example, at least one of the aforementioned first pulverization stage and the aforementioned second pulverization stage), for example, the The shear viscosity is controlled while the pulverization of the porous body is controlled.

For example, at least one of the aforementioned multi-stage pulverizing stages (for example, at least one of the first pulverizing stage and the second pulverizing stage) in the method for manufacturing a low-refractive index layer of the present invention is performed by high-pressure non-media pulverization ).

In the method for producing a low-refractive index layer according to the present invention, the gel is, for example, a gel of a silicon compound containing a saturated bond functional group having at least three functions.

In addition, in the method for producing a low-refractive index layer of the present invention, the gel-containing pulverized substance-containing liquid prepared by the step including the gel pulverization step may be referred to as "gel-containing pulverized substance-containing liquid of the present invention" ".

According to the gel-containing pulverized material liquid of the present invention, for example, by forming a coating film thereof, the pulverized materials in the coating film can be chemically bonded to each other to form the low refractive index of the present invention as a functional porous body. Rate layer. According to the gel-containing pulverized material 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-containing pulverized material-containing liquid of the present invention and a method for producing the same are useful, for example, when manufacturing the low-refractive index layer of the present invention.

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

For example, the gel-containing pulverized material-containing liquid of the present invention may be used to coat (coat) the aforementioned gel-containing pulverized material-containing liquid on a substrate and further dry to obtain a layer (low refractive index layer) having a high porosity. ) Liquid containing pulverized gel. Further, the gel-containing pulverized material-containing liquid of the present invention may be, for example, a gel-containing pulverized material-containing liquid used to obtain a porous body having a high porosity (a thick body or a bulk body). The batch can be produced, for example, by batch-forming a film using the gel-containing pulverized material-containing liquid.

As mentioned above, the low refractive index layer of the present invention may 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 "a void layer of the present invention". For example, the void layer of the present invention having a high porosity can be manufactured by a manufacturing method including the following steps: a step of manufacturing the gel-containing pulverized substance liquid of the present invention, and coating the gel-containing pulverized substance liquid on a substrate Forming a coating film thereon, and drying the coating film.

In addition, for example, a laminated film roll can be manufactured by a manufacturing method including the following steps: manufacturing the gel-containing pulverized liquid of the present invention; unrolling the aforementioned resin film in a roll form; and coating the uncoated resin film. Covering the gel-containing pulverized material liquid to form a coating film; drying the coating film; and, after the drying step, rolling up the laminated film having the low refractive index layer of the present invention formed on the resin film, take. This manufacturing method is hereinafter sometimes referred to as "the manufacturing method of the laminated film roll of this invention." In addition, the laminated film roll manufactured by the manufacturing method of the laminated film roll of this invention below may be called "the laminated film roll of this invention."

[2-2. Gel-containing pulverized material-containing liquid and method for producing the same] The gel-containing pulverized material-containing liquid of the present invention contains, Ground rubber and other solvents mentioned above.

The manufacturing method of the low-refractive index layer of the present invention may include a gel pulverizing step for pulverizing the gel (for example, a porous body gel) in multiple stages, such as the foregoing, and may include the first pulverizing stage and the second pulverizing, for example. stage. Hereinafter, the case where the manufacturing method of the gel-containing pulverized material liquid of this invention contains the said 1st pulverization stage and the said 2nd pulverization stage is mainly demonstrated. The case where the gel is a porous body (porous body gel) will be mainly described below. However, the present invention is not limited to this, and the description of the case where the gel is a porous body (porous body gel) can be similarly applied to the case where the gel is a porous body. The plurality of pulverization stages (for example, the first pulverization stage and the second pulverization stage) in the method for producing a low-refractive index layer of the present invention may be collectively referred to as a "gel pulverization step".

The gel-containing pulverized material-containing liquid of the present invention can be used for producing a functional porous body capable of exhibiting the same function as the air layer (for example, low refraction) as described later. The functional porous body may be, for example, the low refractive index layer of the present invention. Specifically, the gel-containing pulverized material liquid prepared by the production method of the present invention contains the pulverized material of the porous body gel, and the three-dimensional structure of the pulverized material is not pulverized, and the three-dimensional structure of the porous body gel is destroyed. The new three-dimensional structure of unpulverized porous gels is quite different. Therefore, for example, a coating film (precursor of a functional porous body) formed by using the gel-containing pulverized material liquid becomes a new pore structure that cannot be obtained by forming a layer formed by using the gel of the non-pulverized porous body. (New type of void structure). Thereby, the said layer can exhibit the same function (for example, the same low refractive index) as an air layer. The gel-containing pulverized material liquid of the present invention may, for example, form a new three-dimensional structure as the coating film (functional porous body precursor) after the pulverized material contains a residual silanol group, and then pulverize the pulverized material. The substances are chemically bonded to each other. Thereby, although the formed functional porous body has a structure having voids, it can maintain sufficient strength and flexibility. Therefore, according to the present invention, a functional porous body can be easily and simply provided to various objects. The gel-containing pulverized material-containing liquid produced by the production method of the present invention is very useful, for example, in the production of the aforementioned porous structure which can be used as a substitute for the air layer. In addition, the air layer must be laminated by providing a gap between the member and the member with a spacer or the like therebetween, so as to form an air layer between the members. However, the functional porous body formed using the gel-containing pulverized material-containing liquid of the present invention can exhibit the same function as the air layer as long as the functional porous body is disposed at the target portion. Therefore, as described above, it is easier and simpler to provide the same functions as the air layer to various objects than to form the air layer.

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

In the gel-containing pulverized substance-containing liquid of the present invention, the volume average particle diameter range of the pulverized substance (particles of the porous body gel) is, for example, 10 to 1000 nm, or 100 to 500 nm, or 200 to 300 nm. The volume average particle size indicates that the particle size of the pulverized material in the gel-containing pulverized material liquid of the present invention varies. The volume average particle diameter is as described above, and 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 the gel-containing pulverized material liquid of the present invention, the gel concentration of the pulverized material is not particularly limited. For example, particles having a particle size of 10 to 1000 nm are 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-containing pulverized material liquid of the present invention, the aforementioned gel (for example, a porous body gel) is not particularly limited, and examples thereof include a silicon compound.

The silicon compound is not particularly limited, and examples thereof include a silicon compound containing a saturated bond functional group having at least three functions. The aforementioned "functional group containing a saturated bond having 3 or less functional groups" means a state in which the silicon compound has 3 or less functional groups and the functional groups are saturated with silicon (Si).

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

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

The X and R ^{1 are, for} example, the same as X and R ¹ in the formula (1). The aforementioned R ² may be exemplified by, for example, R ¹ in the formula (1) described later.

Specific examples of the silicon compound represented by the formula (2) include compounds represented by the following formula (2 ′) in which X is 3. In the following formula (2 '), R ¹ and R ² are respectively the same as the aforementioned formula (2). When R ¹ and R ² are methyl, the silicon compound is trimethoxy (methyl) silane (hereinafter also referred to as "MTMS"). [Chemical Formula 2]

In the gel-containing pulverized material liquid of the present invention, the pulverized material concentration of the porous body gel in the solvent is not particularly limited, and is, for example, 0.3 to 50% (v / v), 0.5 to 30% (v / v). ), 1.0 ~ 10% (v / v). If the concentration of the pulverized material is too high, for example, the fluidity of the gel-containing pulverized material liquid may significantly decrease, and condensate or coating marks may occur during coating. On the other hand, if the concentration of the above-mentioned pulverized material is too low, not only a considerable amount of time will be spent on drying the solvent, but also the residual solvent after drying will be increased, and thus the porosity may be reduced.

The physical properties of the pulverized gel-containing liquid of the present invention are not particularly limited. The shear viscosity of the gel-containing pulverized material liquid is, for example, at the shearing speed of 10001 / s, for example, the following ranges: 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, a coating mark may be generated and a transfer rate of gravure coating may be reduced, and other undesirable conditions may occur. Conversely, 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-containing pulverized material-containing liquid of the present invention, the solvent may be, for example, a dispersion medium. The dispersion medium (hereinafter also referred to as "solvent for coating") is not particularly limited, and examples thereof include a gelling solvent and a solvent for pulverization as described later, and the solvent for pulverization is preferable. The coating solvent includes an organic solvent having a boiling point of 70 ° C. or higher and lower than 180 ° C. and a saturated vapor pressure at 20 ° C. of 15 kPa or less.

Examples of the aforementioned organic solvent include 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 ether Ether, xylene, cresol, chlorobenzene, isobutyl acetate, isopropyl acetate, isoamyl acetate, ethyl acetate, n-butyl acetate, n-propyl acetate, n-pentyl acetate, cyclohexanol, Cyclohexanone, 1,4-bis Alkane, 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, and the like. In addition, the dispersion medium may contain a suitable amount of a perfluoro-based surfactant, a silicon-based surfactant, or the like which can reduce the surface tension.

The gel-containing pulverized material-containing liquid of the present invention may be, for example, a sol-like particle liquid of the pulverized material in a sol form dispersed in the dispersion medium. For example, the gel-containing pulverized material-containing liquid of the present invention is coated on a substrate and dried, and then chemically cross-linked by a bonding step described later to continuously form a void layer having a film strength of a certain degree or more. In addition, the "sol" of the present invention means that the three-dimensional structure of the gel is pulverized, and the pulverized material (that is, the porous three-dimensional structured porous body sol particles having a partially voided structure) is dispersed in a solvent to show flow. Sexual status.

The gel-containing pulverized material liquid of the present invention may contain, for example, a catalyst for chemically bonding the pulverized materials of the gel to each other. The content ratio of the catalyst is not particularly limited, and it is, for example, 0.01 to 20% by weight, 0.05 to 10% by weight, or 0.1 to 5% by weight with respect to the weight of the ground material of the gel.

The gel-containing pulverized material-containing liquid of the present invention may further contain, for example, a crosslinking auxiliary agent for indirectly bonding the pulverized materials of the gel. The content of the cross-linking adjuvant is not particularly limited, and for example, it is 0.01 to 20% by weight, 0.05 to 15% by weight, or 0.1 to 10% by weight based on the weight of the pulverized material of the gel.

In the gel-containing pulverized material-containing liquid of the present invention, the functional group ratio of the functional unit monomers of the gel may not contribute to the cross-linking structure in the gel. For example, the functional group ratio may be 30 mol% or less and 25 mol. % Or less, 20 mol% or less, 15 mol% or less, and may be, for example, 1 mol% or more, 2 mol% or more, 3 mol% or more, and 4 mol% or more. The ratio of the functional groups not contributing to the cross-linked structure in the gel can be measured, for example, in the following manner.

(Method for measuring the ratio of functional groups that does not contribute to the cross-linked structure in the gel) After drying the gel, the solid NMR (Si-NMR) is measured, and the residual silanol groups that do not contribute to the cross-linked structure are calculated from the peak ratio of NMR. (Functional groups that do not contribute to the cross-linked structure in the gel) ratio. Moreover, even if the said functional group is other than a silanol group, the ratio of the functional group which does not contribute to the crosslinking structure in a gel can be calculated from the peak ratio of NMR based on this.

The following is an example to illustrate the method for producing the gel-containing pulverized product liquid of the present invention. The gel-containing pulverized material-containing liquid of the present invention is referred to the following description unless specifically described.

In the method for producing a gel-containing pulverized material liquid of the present invention, the mixing step is a step of mixing the particles (pulverized material) of the porous body gel with the solvent, and it is optional. Specific examples of the mixing step include a step of mixing a pulverized substance of a gel-like silicon compound (silicon compound gel) with a dispersing medium. The gel-like silicon compound is composed of Manufactured from silicon compounds. In the present invention, the pulverized material of the porous body gel can be obtained from the porous body gel by a gel pulverization step described later. The pulverized material of the porous body gel can be produced, for example, from the porous body gel that has been subjected to a ripening process described later.

In the method for producing a gel-containing pulverized product liquid of the present invention, the gelation step is, for example, a step of gelling a porous porous body in a solvent to form the aforementioned porous body gel, and the details of the aforementioned gelation step For example, it is a step of forming a silicon compound gel by gelling a silicon compound containing a saturated bond functional group having at least three functions described above in a solvent.

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

The gelation step is, for example, a step of gelling the silicon compound of the monomer by a dehydration condensation reaction in the presence of a dehydration condensation catalyst, thereby preparing a silicon compound gel. The silicon compound gel has, for example, a residual silanol group, and the residual silanol group should be appropriately adjusted in accordance with the chemical bonding between the ground particles of the silicon compound gel described later.

In the aforementioned gelation step, the aforementioned silicon compound is not particularly limited as long as it is a substance that is gelled by a dehydration condensation reaction. For example, the silicon compounds are bonded to each other by the dehydration condensation. The bonding between the aforementioned silicon compounds is, for example, hydrogen bonding or intermolecular bonding.

Examples of the silicon compound include a silicon compound represented by the following formula (1). Since the silicon compound of the following formula (1) has a hydroxyl group, the silicon compound of the following formula (1) can achieve 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 linear alkyl group or a branched alkyl group. The carbon number of the R ^{1 is} , for example, 1 to 6, 1 to 4, or 1 to 2. Examples of the linear alkyl group include methyl, ethyl, propyl, butyl, pentyl, and hexyl, and examples of the branched alkyl group include isopropyl and isobutyl. The X is, for example, 3 or 4.

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 formula (1), and is, for example, a methyl group. When R ¹ is a methyl group, the silicon compound is ginsyl (hydroxy) methyl silane. When X is 3, the silicon compound is, for example, a trifunctional silane having three functional groups.

[Chemical Formula 4]

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

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

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

The aforementioned hydrolysis method is not particularly limited, and may be carried out by a chemical reaction in the presence of a catalyst, for example. Examples of the catalyst include acids such as oxalic acid and acetic acid. The hydrolysis reaction can be performed, for example, by slowly dropping and mixing the oxalic acid aqueous solution into the dimethylarsin solution of the silicon compound precursor at room temperature, followed by directly stirring 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 in order to more effectively visualize subsequent gelation, maturation, and heating and immobilization after formation of a void structure.

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

The silicon compound of the aforementioned monomer is not particularly limited, and can be appropriately selected, for example, according to the application of the functional porous body to be produced. In the production of the above-mentioned functional porous body, for example, when low-refractive index properties are valued, from the viewpoint of excellent low-refractive index properties, the silicon compound is preferably the trifunctional silane; and strength (such as scratch resistance) is also important. In the case of the above-mentioned properties, the silicon compound is preferably the aforementioned tetrafunctional silane from the viewpoint of excellent scratch resistance. The silicon compound is a raw material of the silicon compound gel. For example, only one kind may be used, or two or more kinds may be used in combination. As a specific example, the silicon compound may contain, for example, only the aforementioned trifunctional silane, only the aforementioned tetrafunctional silane, or both the aforementioned trifunctional silane and the aforementioned tetrafunctional silane, and may further include other silicon compounds. . When two or more 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 silicon compound can be performed, for example, by a dehydration condensation reaction between the porous bodies. The dehydration condensation reaction is preferably performed in the presence of a catalyst. The catalyst may be, for example, an acid catalyst and an alkaline catalyst, such as hydrochloric acid, oxalic acid, sulfuric acid, etc., and the alkaline catalyst. There are ammonia, potassium hydroxide, sodium hydroxide, and ammonium hydroxide. The dehydration condensation catalyst may be an acid catalyst or an alkaline catalyst, and an alkaline catalyst is preferred. In the dehydration condensation reaction, the amount of the catalyst added to the porous body is not particularly limited. For example, the catalyst is 0.01 to 10 moles, 0.05 to 7 moles, 0.1 to 1 mole of the porous body. ~ 5 moles.

The gelation of the porous body such as the silicon compound is preferably performed in a solvent, for example. The proportion of the porous body in the solvent is not particularly limited. Examples of the aforementioned solvent include dimethylsulfinium (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 1 type, and 2 or more types may be used together, for example. The solvent used for the above-mentioned gelation is hereinafter also referred to as a "solvent for gelation".

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

There is no particular limitation on the gel form of the porous body obtained in the gelation step. Generally speaking, "gel" refers to a structure in which a solute has agglomerates due to the loss of independent motility due to interaction, and has a solidified state. In general, in a gel, a wet gel refers to a person that contains a dispersing medium and has the same structure as a solute in the dispersing medium, and a xerogel refers to a solvent that removes the solvent and has a network structure with voids. In the present invention, the aforementioned silicon compound gel is preferably a wet gel, for example. When the porous body gel is a silicon compound gel, there is no particular limitation on the residual silanol groups of the silicon compound gel, and for example, the ranges described below can be similarly cited.

For example, the porous body 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. The maturing step is a step of maturing the gelled porous body (porous body gel) in a solvent. In the maturing step, the conditions for the maturing treatment are not particularly limited, and for example, the porous body gel may be grown at a predetermined temperature in a solvent. According to the aforementioned aging treatment, for example, the porous body gel having a three-dimensional structure prepared by gelation can be used to further grow the primary particles, thereby increasing the size of the particles themselves. Furthermore, as a result, the contact state of the neck portion where the particles contact each other can be increased from point contact to surface contact. The porous body gel subjected to the above-mentioned aging treatment, for example, can increase the strength of the gel itself, and as a result, the strength of the three-dimensional basic structure of the pulverized material can be further improved. Thus, when the coating film is formed by using the gel-containing pulverized material liquid of the present invention, for example, even in the drying step after coating, the pore size of the void structure formed by stacking the three-dimensional basic structure can be suppressed. In the drying step, the solvent in the coating film is evaporated and shrinks.

The lower limit of the temperature for the ripening treatment is, for example, 30 ° C or higher, 35 ° C or higher, or 40 ° C or higher. The upper limit is, for example, 80 ° C or lower, 75 ° C or lower, or 70 ° C or lower, and the ranges are, for example, 30 to 80 ° C, 35 to 75 °. ℃, 40 ~ 70 ℃. The predetermined time is not particularly limited, and its lower limit is, for example, 5 hours or more, 10 hours or more, 15 hours or more, and its upper limit is, for example, 50 hours or less, 40 hours or less, and 30 hours or less, and its range is, for example, 5 to 50 hours, 10 to 40 hours, 15-30 hours. In addition, as for the optimal conditions for ripening, for example, the conditions for increasing the size of the primary particles in the porous body gel and increasing the contact area of the neck are preferably set as described above. Moreover, in the said aging process, the temperature of the said aging process should consider the boiling point of the solvent to be used, for example. For example, when the ripening temperature is too high, the solvent may be excessively volatilized, and due to the concentration of the coating solution, a disadvantage such as pores with a three-dimensional void structure may occur. On the other hand, when the ripening process is too low, for example, when the ripening temperature is too low, not only the effect obtained by the ripening cannot be fully obtained, but also the temperature deviation of the mass production process may increase, and a product of poor quality may be produced.

The said aging process can use the same solvent as the said gelatinization process, and, specifically, it is suitable to perform directly on the reactant after the said gel processing (namely, the said solvent containing the said porous body gel). For example, when the porous body gel is the silicon compound gel, the number of moles of the residual silanol groups contained in the silicon compound gel after the gelation and maturation treatment is completed is used for gelation. The lower limit of the ratio of residual silanol groups when the alkoxy mole number of the raw material (such as the aforementioned silicon compound or its precursor) is 100, for example, the lower limit is 50% or more, 40%, or 30% or more, and the upper limit is 1 % Or less, 3% or less, and 5% or less. The ranges are, for example, 1 to 50%, 3 to 40%, and 5 to 30%. For the purpose of increasing the hardness of the aforementioned silicon compound gel, for example, the lower the mole number of the residual silanol group, the better. If the molar number of the residual silanol group is too high, for example, when the functional porous body is formed, the void structure may not be maintained to crosslink the precursor of the functional porous body. On the other hand, if the molar number of the residual silanol groups is too low, for example, in the aforementioned bonding step, the precursor of the functional porous body may not be crosslinked, and thus sufficient film strength may not be imparted. In addition, the above is an example of a residual silanol group. For example, when the silicon compound that has been modified with various reactive functional groups is used as a raw material of the silicon compound gel, the same phenomenon can be applied to each functional group.

For example, the porous body gel obtained by the gelation is subjected to a ripening process in the ripening step, for example, a solvent replacement step is performed, and is then supplied to the gel pulverizing step. The solvent replacement step may replace the solvent with another solvent.

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

As described above, the gel shape control step for controlling the shape and size of the gel may be performed before the solvent replacement step (for example, after the ripening step). The shape and size of the gel controlled in the gel shape control step are not particularly limited, as described above. The gel shape control step may be performed by dividing (eg, cutting) the gel into a three-dimensional (three-dimensional body) having an appropriate size and shape, for example.

In addition, as described above, after the solvent replacement step is performed on the gel, the gel pulverization step is performed. The solvent replacement step may replace the solvent with another solvent. This is because if the aforementioned solvent is not replaced with the aforementioned other solvent, for example, the catalyst and solvent used in the gelation step continue to remain after the aforementioned maturation step, it may affect the gel containing the gel which is finally produced over time. The useful life of the pulverized material liquid may reduce the drying efficiency of the coating film formed by using the gel-containing pulverized material liquid during drying. The other solvents in the gel pulverization step are hereinafter also referred to as "solvents for pulverization".

The pulverizing solvent (other solvents) is not particularly limited, and for example, an organic solvent can be used. Examples of the organic solvent 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 isopropyl alcohol (IPA), ethanol, methanol, n-butanol, 2-butanol, isobutanol, pentanol, propylene glycol monomethyl ether (PGME), methylcellulose, and acetone. The above-mentioned pulverizing solvent may be, for example, one kind or a combination of two or more kinds.

In the case where the polarity of the solvent for pulverization is very low, for example, the solvent replacement step may be divided into a plurality of steps of the solvent replacement step, and in the solvent replacement step, the hydrophilicity of the other solvents is later. The running phase is lower than the preceding phase. With this setting, for example, the solvent replacement efficiency can be improved, and the residual amount of the gel-producing solvent (for example, DMSO) in the gel can be extremely reduced. For a specific example, for example, the aforementioned solvent replacement step can be divided into three steps for the solvent replacement step. In the first solvent replacement step, DMSO in the gel is first replaced with water, and then the coagulation is performed in the second solvent replacement step. The aforementioned water in the gel was replaced with IPA, and the aforementioned IPA in the gel was replaced with isobutanol in the third replacement stage.

The combination of the gelling solvent and the pulverizing solvent is not particularly limited, and examples thereof include a combination of DMSO and IPA, a combination of DMSO and ethanol, a combination of DMSO and isobutanol, and a combination of DMSO and n-butanol. In this way, by changing the solvent for gelation to the solvent for pulverization, for example, a more uniform coating film can be formed in the coating film formation described later.

The said solvent replacement process is not specifically limited, For example, it can perform it as follows. That is, first, the gel produced by the gel manufacturing step (such as the gel after the aging process) is immersed or contacted with the other solvent, and the gel manufacturing catalyst in the gel is generated by a condensation reaction. The alcohol component, water, and the like are dissolved in the other solvents. Thereafter, the solvent which has been impregnated or contacted with the gel is discarded, and the gel is impregnated or contacted with a new solvent again. This procedure is repeated until the remaining amount of the gel-producing solvent in the gel becomes a desired amount. The immersion time per time is, for example, 0.5 hours or more, 1 hour or more, or 1.5 hours or more. The upper limit value is not particularly limited, and is, for example, 10 hours or less. In addition, the impregnation of the solvent may be adapted so that the solvent continuously contacts the gel. The temperature during the dipping is not particularly limited, and may be, for example, 20 to 70 ° C, 25 to 65 ° C, or 30 to 60 ° C. Heating can make the solvent replacement progress rapidly, and the amount of necessary solvent required for the replacement can be small, but the solvent replacement can be easily performed at room temperature. In addition, for example, when the solvent replacement step is divided into a plurality of stages of the solvent replacement stage and executed, each stage of the multi-stage solvent replacement stage may be performed as described above.

In addition, for example, the solvent replacement step may be divided into a plurality of stages of the solvent replacement stage and the hydrophilicity of the other solvents may be lower in the later stage than in the preceding stage. In this way, the solvent for replacement (the other solvents mentioned above) can be gradually changed from a solvent having a high hydrophilicity to a solvent having a low hydrophilicity (high hydrophobicity), thereby enabling a solvent for producing a gel in a gel. The amount of residuals has become extremely small. According to the above method, for example, a void layer having a high porosity (and therefore, a low refractive index) can be further produced, for example.

After the solvent replacement step is performed, the residual amount of the solvent for producing a gel in the gel is preferably 0.005 g / ml or less, more preferably 0.001 g / ml or less, and particularly preferably 0.0005 g / ml or less. The lower limit of the remaining amount of the remaining amount of the solvent for producing a gel in the gel is not particularly limited, and may be, for example, zero, less than or less than a detection limit.

After the solvent replacement step is performed, the residual amount of the solvent for producing a gel in the gel can be measured, for example, by the following method.

(Method for measuring the remaining amount of the gel-producing solvent in the gel) 0.2 g of the gel was added, 10 ml of acetone was added, and extraction was performed by shaking at 120 rpm with a shaker at room temperature for 3 days. 1 μl of the extract was injected into a gas chromatography analyzer (manufactured by Aglent, trade name 7890A) and analyzed. In addition, in order to confirm the reproducibility of the measurement, for example, the measurement may be performed by sampling at a measurement number of n = 2 (two measurement times) or more. Further, a test line was prepared from the sample, and the amount of each component per 1 g of the gel was determined, and the remaining amount of the gel-producing solvent per 1 g of the gel was calculated.

When the solvent replacement step is divided into a plurality of steps of the solvent replacement step and the hydrophilicity of the other solvent is lower in the later stage than in the preceding stage, the other solvent (the solvent for replacement) is not particularly limited. However, in the solvent replacement stage performed last, the other solvent (solvent for replacement) is preferably a solvent for producing a void layer. Examples of the solvent for producing the void layer include solvents having a boiling point of 140 ° C or lower. Examples of the solvent for producing the void layer include alcohols, ethers, ketones, ester solvents, aliphatic hydrocarbon solvents, and aromatic solvents. Specific examples of the alcohol having a boiling point of 140 ° C or lower include isopropyl alcohol (IPA), ethanol, methanol, n-butanol, 2-butanol, isobutanol (IBA), 1-pentanol, and 2-pentanol. Specific examples of the ether having a boiling point of 140 ° C or lower include propylene glycol monomethyl ether (PGME), methylcellulose, and ethylcellulose. Specific examples of the ketone having a boiling point of 140 ° C. or lower include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclopentanone. Specific examples of the ester-based solvent having a boiling point of 140 ° C or lower include ethyl acetate, butyl acetate, isopropyl acetate, and n-propyl acetate. Specific examples of the aliphatic hydrocarbon-based solvent having a boiling point of 140 ° C or lower include hexane, cyclohexane, heptane, and octane. Specific examples of the aromatic solvent having a boiling point of 140 ° C or lower include toluene, benzene, xylene, and anisole. From the viewpoint of preventing the substrate (for example, a resin film) from being easily eroded during coating, the solvent for producing the void layer is preferably an alcohol, an ether, or an aliphatic hydrocarbon-based solvent. The pulverizing solvent may be, for example, one kind or a combination of two or more kinds. In particular, from the viewpoint of low volatility at room temperature, isopropyl alcohol (IPA), ethanol, n-butanol, 2-butanol, isobutanol (IBA), pentanol, propylene glycol monomethyl ether ( PGME), methylcellulose, heptane, and octane are preferred. In particular, in order to suppress the scattering of particles of a gel material (such as a silicon dioxide compound), the saturation vapor pressure of the aforementioned solvent for producing a void layer should not be too high (the volatility is not too high). Such a solvent is preferably a solvent having an aliphatic group having 3 or more carbon atoms, and a solvent having an aliphatic group of 4 or more carbon atoms is preferred. The solvent having an aliphatic group having 3 or 4 or more carbon atoms may be, for example, an alcohol. Examples of such solvents include isopropyl alcohol (IPA), isobutanol (IBA), n-butanol, 2-butanol, 1-pentanol, and 2-pentanol, and isobutanol (IBA) It's better.

The other solvents (solvent for replacement) other than the solvent replacement step performed last are not particularly limited, and examples thereof include alcohols, ethers, and ketones. Specific examples of the alcohol include isopropyl alcohol (IPA), ethanol, methanol, n-butanol, 2-butanol, isobutanol (IBA), and pentanol. Specific examples of the ether include propylene glycol monomethyl ether (PGME), methylcellulose, and ethylcellulose. Specific examples of the ketone include acetone. The other solvent (solvent for replacement) may be substituted for the solvent for gel production or the other solvent (replacement solvent) at a previous stage. In addition, it is preferable that the other solvents (replacement solvents) other than the aforementioned solvent replacement stage are solvents that will not remain in the gel eventually or that will not easily attack the substrate (such as a resin film) during coating. . From the viewpoint of not easily attacking the substrate (such as a resin film) during coating, it is preferable that the other solvent (replacement solvent) other than the solvent replacement stage performed last is an alcohol. As such, it is preferred that the other solvent in at least one of the multi-stage solvent replacement stages is an alcohol.

In the aforementioned solvent replacement stage, the other solvents may be, for example, water or a mixed solvent containing water in an arbitrary ratio. As long as it is water or a mixed solvent containing water, it has high compatibility with a highly hydrophilic gel-producing solvent (for example, DMSO), so it is easy to replace the aforementioned gel-producing solvent, and it is also excellent in terms of cost.

The aforementioned multi-stage solvent replacement stage may also include the following stages: the stage where the other solvent is water; the stage where the aforementioned other solvent is a solvent having an aliphatic group having a carbon number of 3 or less; and the aforementioned stage which is performed thereafter The other solvent is a step of a solvent having an aliphatic group having 4 or more carbon atoms. In addition, at least one of the solvent having an aliphatic group with a carbon number of 3 or less and the solvent having an aliphatic group with a carbon number of 4 or more may be an alcohol. The alcohol having an aliphatic group having a carbon number of 3 or less is not particularly limited, and examples thereof include isopropyl alcohol (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 a carbon number of 3 or less may be isopropanol, and the solvent having an aliphatic group having a carbon number of 4 or more may be isobutanol.

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

In this way, the reason (mechanism) for producing a low-refractive void layer by reducing the remaining amount of the gel-producing solvent in the gel is not clear, but it can be estimated as follows, for example. That is, as described above, in order to perform the gelation reaction, the solvent for gel production is preferably a high-boiling-point solvent (such as DMSO). In addition, when a sol solution prepared from the gel is applied and dried to produce a void layer, it is difficult to use a normal drying temperature and drying time (not particularly limited, but for example, performed at 100 ° C for 1 minute). The aforementioned high-boiling solvents are completely removed. This is because if the drying temperature is too high or the drying time is too long, problems such as deterioration of the substrate may occur. In addition, the high-boiling-point solvent remaining during the coating and drying will enter between the pulverized materials of the gel, cause the pulverized materials to slide with each other, and cause the pulverized materials to closely accumulate, thereby reducing the void ratio. It is difficult to develop a low refractive index. That is, if the remaining amount of the high-boiling-point solvent is reduced on the contrary, this phenomenon can be suppressed and a low refractive index can be exhibited. However, these are only examples of the speculative mechanism and do not limit the present invention in any way.

In addition, in the present invention, the "solvent" (for example, a solvent for producing a gel, a solvent for producing a void layer, a solvent for replacement, etc.) can be used without dissolving the gel or its pulverized substance. The substance or the like is dispersed or precipitated in the aforementioned solvent.

As mentioned above, the said gel manufacturing solvent may have a boiling point of 140 degreeC or more, for example.

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

When the solvent replacement step is divided into a plurality of steps of the solvent replacement step, the method is not particularly limited. For example, the solvent replacement step of each step can be performed in the following manner. That is, first, the gel is immersed or contacted with the other solvent, and the gel-making catalyst in the gel, the alcohol component produced by the condensation reaction, water, and the like are dissolved in the other solvent. Thereafter, the solvent which has been impregnated or contacted with the gel is discarded, and the gel is impregnated or contacted with a new solvent again. This procedure is repeated until the remaining amount of the gel-producing solvent in the gel becomes a desired amount. The immersion time per time is, for example, 0.5 hours or more, 1 hour or more, or 1.5 hours or more. The upper limit value is not particularly limited, and is, for example, 10 hours or less. In addition, the impregnation of the solvent may be adapted so that the solvent continuously contacts the gel. The temperature during the dipping is not particularly limited, and may be, for example, 20 to 70 ° C, 25 to 65 ° C, or 30 to 60 ° C. Heating can make the solvent replacement progress rapidly, and the amount of necessary solvent required for the replacement can be small, but the solvent replacement can be easily performed at room temperature. This solvent replacement step was performed several times, and the other solvent (the solvent for replacement) was gradually changed from a solvent with high hydrophilicity to a solvent with low hydrophilicity (high hydrophobicity). In order to remove a highly hydrophilic gel-producing solvent (for example, DMSO), as described above, it is simple and efficient to use water as a solvent for replacement at the beginning. Next, after removing DMSO and the like with water, the water in the gel is replaced in the order of isopropyl alcohol ⇒ isobutanol (solvent for coating), for example. That is, the compatibility between water and isobutanol is low. Therefore, the solvent can be efficiently replaced by isopropyl alcohol and then isobutanol as a coating solvent. However, this is an example. As mentioned above, the other solvents (solvent for replacement) are not particularly limited.

In the present invention, the method for producing a gel is, for example, as described above, and the solvent replacement stage may be performed several times, and the other solvent (the solvent for replacement) may be slowly changed from a solvent with high hydrophilicity to a solvent with low hydrophilicity ( Highly hydrophobic) solvents. Thereby, as described above, the residual amount of the gel-producing solvent in the gel can be extremely reduced. In addition, for example, it is possible to reduce the amount of solvent used to reduce the amount of solvent used more than the solvent replacement in one stage by using only the coating solvent, thereby reducing the cost.

Then, a gel pulverization step is performed after the solvent replacement step, that is, the gel is pulverized in the pulverization solvent. For another example, as described 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 thereafter. The gel concentration measurement after the solvent replacement step and before the gel pulverization step can be performed, for example, in the following manner. That is, first, after the solvent replacement step, the gel is taken out of the other solvents (solvent for pulverization). The gel is, for example, agglomerates having an appropriate shape and size (for example, lumps) that have been controlled by the aforementioned gel morphology controlling step. Next, the solvent adhering to the agglomerates of the gel was removed, and then the concentration of solid components in one agglomerate of the gel was measured by a weight drying method. At this time, in order to obtain the reproducibility of the measured value, a plurality of (for example, 6) clumps taken out at random are measured, and the difference between the average value and the value is calculated. The concentration adjustment step may, for example, further reduce the gel concentration of the gel-containing liquid by further adding the other solvent (solvent for pulverization). In addition, the concentration adjustment step may conversely increase the gel concentration of the gel-containing liquid by evaporating the other solvent (solvent for pulverization).

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

The first crushing stage and the second crushing stage will be described below.

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

The volume average particle diameter of the particles of the porous body gel obtained in the first pulverization step and the volume average particle diameter of the particles of the porous body gel obtained in the second pulverization step are as described above. The measurement method of the said volume average particle diameter is also the same as the above.

The shear viscosity of the gel-containing pulverized material-containing liquid after the first pulverization step and the shear viscosity of the liquid after the second pulverization step are as described above. The method for measuring the aforementioned shear viscosity is similar to that described above.

In addition, for example, as described above, the gel concentration of the gel-containing liquid may be measured immediately after the first pulverization stage, and only the liquid having the gel concentration within a predetermined numerical range may be supplied to the second pulverization stage. Thereby, the concentration control of the aforementioned gel-containing liquid is performed.

There is no particular limitation on the pulverization method of the aforementioned porous body gel. For example, it can be performed by the following devices: high-pressure medium-free pulverizer, ultrasonic homogenizer, high-speed rotary homogenizer, high-pressure extrusion pulverizer, and other wet methods that use cavitation No media pulverizer, etc. The first pulverization stage and the second pulverization stage may be performed with the same pulverization method or with a pulverization method that is different from each other.

As for the pulverization method, it is preferable to perform at least one of the first pulverization step and the second pulverization step by a method of pulverizing the porous body gel by controlling energy. The method for pulverizing the porous body gel by controlling energy may be a method using a high-pressure medium-free pulverizer or the like.

In the method for pulverizing the porous body gel by ultrasonic waves, although the pulverization strength is strong, it is difficult to control (adjust) the pulverization. In contrast, if the porous body gel is pulverized by controlling energy, the pulverization can be performed while controlling (adjusting) the pulverization. Thereby, a uniform gel-containing pulverized product liquid can be produced with a limited operation amount. Therefore, for example, the above-mentioned gel-containing pulverized material liquid can be produced at a step of mass production.

A device such as a bead mill for pulverizing a medium physically breaks the void structure of the gel during pulverization. In contrast, a cavitation-type pulverizing device such as a homogenizer is a medium-free method, so it uses high-speed shearing. Shear force peels off the weakly-associated porous particle junction that is already contained in the three-dimensional structure of the gel. In this way, a new sol three-dimensional structure can be obtained by pulverizing the porous body gel. The three-dimensional structure can maintain a void structure with a certain range of particle size distribution, for example, when forming a coating film. The accumulation during drying again forms a void structure. The aforementioned pulverization conditions are not particularly limited, and for example, it is preferable to pulverize the gel in such a manner that the solvent is not volatilized by instantaneously imparting a high-speed flow. For example, it is preferable to grind | pulverize so that it may become the grind | pulverized material of the particle size dispersion | variation as mentioned above (for example, a volume average particle diameter or a particle size distribution). It is assumed that when the amount of work such as pulverization time and strength is insufficient, for example, coarse particles remain, not only dense pores cannot be formed, but also appearance defects may be increased, so that high quality cannot be obtained. On the other hand, when the aforementioned amount of work is excessive, for example, sol particles having a finer particle size distribution than a desired particle size distribution may be formed, and the void size formed by coating and drying may become fine, and the desired void ratio may not be achieved.

In at least one of the first pulverization stage and the second pulverization stage, it is desirable to control the pulverization of the porous body while measuring the shear viscosity of the liquid. The specific method may be, for example, a method of adjusting a sol liquid having both desired shear viscosity and extremely excellent uniformity in the middle stage of the aforementioned pulverization stage, monitoring the shear viscosity of the aforementioned liquid in-line, and Feedback to the method of the aforementioned crushing stage. This makes it possible to produce a gel-containing pulverized material-containing liquid that has both the desired shear viscosity and extremely excellent uniformity. Therefore, for example, the above-mentioned gel-containing pulverized material-containing liquid can be controlled in accordance with its use.

After the pulverization stage, when the porous body gel is the silicon compound gel, the ratio of the residual silanol groups contained in the pulverized material is not particularly limited. For example, as shown with the silicon compound gel after the aging treatment, The range is the same.

In the manufacturing method of the present invention, the classification step may be further performed after at least one of the gel pulverization step (the first pulverization step and the second pulverization step). The classification step is to classify particles of the porous body gel. The "classification" refers to, for example, separating the particles of the porous body gel according to the particle size. The classification method is not particularly limited, and can be carried out with a sieve. In this way, by performing the pulverization treatment in a plurality of stages, as described above, the pulverized material of the aforementioned porous body gel becomes a material having extremely excellent uniformity. Therefore, when the pulverized material of the porous body gel is applied to an application such as an optical member, the optical member or the like can have a good appearance. In addition, by classifying the pulverized material of the porous body gel, the optical member and the like can have a good appearance.

After the gel pulverization step and any of the classification steps, the ratio of the pulverized material in the solvent containing the pulverized material is not particularly limited. For example, the conditions in the gel-containing pulverized liquid of the present invention may be exemplified. . The ratio may be, for example, a condition including a solvent of the pulverized material after the gel pulverization step, or a condition that is adjusted after the gel pulverization step and before being used as the gel-containing pulverized material-containing liquid.

In the manner described above, a liquid (for example, a suspension) containing the fine pores (a pulverized product of a gel-like compound) can be prepared. In addition, by producing a liquid containing the fine pore particles or adding a catalyst for chemically bonding the fine pore particles to each other after the liquid containing the fine pore particles is produced, a containing liquid containing the fine pore particles and the catalyst can be manufactured. The addition amount of the catalyst is not particularly limited, and it is, for example, 0.01 to 20% by weight, 0.05 to 10% by weight, or 0.1 to 5% by weight with respect to the weight of the pulverized product of the gelled silicon compound. The catalyst may be, for example, a catalyst that promotes cross-linking and bonding between the fine pore particles. The chemical reaction for chemically bonding the aforementioned fine pore particles to each other is preferably a dehydration condensation reaction of a residual silanol group contained in the silica sol molecule. By using the aforementioned catalyst to promote the reaction between the hydroxyl groups of the silanol group, continuous film formation that hardens the void structure in a short time can be achieved. Examples of the catalyst include a photoactive catalyst and a thermally active catalyst. With the aforementioned 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, it is not easy to cause the entire shrinkage of the void layer in the void layer forming step, so that a high void ratio can be maintained. In addition to the catalyst, a catalyst-generating substance (catalyst generating agent) may be used or simply replaced. For example, in addition to the aforementioned photoactive catalyst, a substance that generates a catalyst by light (photocatalyst generating agent) may be used or simply replaced, and in addition to the aforementioned thermoactive catalyst, a substance that generates a catalyst by heat may also be used (Thermal catalyst generator) or simply replace it. The aforementioned photocatalyst generator is not particularly limited, and examples thereof include a photobase generator (a substance that generates an alkaline catalyst by light irradiation), a photoacid generator (a substance that generates an acidic catalyst by light irradiation), and the like. The generating agent is suitable. Examples of the aforementioned photobase generator include 9-anthrylmethyl N, N-diethylcarbamate (trade name WPBG-018), (E) -1- [3 -(2-hydroxyphenyl) -2-propenyl] piperidine ((E) -1- [3- (2-hydroxyphenyl) -2-propenoyl] piperidine, trade name WPBG-027), 1- (anthracene Quinone-2-yl) ethyl imidazole carboxylate (1- (anthraquinon-2-yl) ethyl imidazole carboxylate, trade name WPBG-140), 2-nitrobenzyl-4-methylpropanyloxypiperidine -1-carboxylic acid ester (trade name WPBG-165), 1,2-diisopropyl-3- [bis (dimethylamino) methylenefluorene] 2- (3-benzylidenephenyl) ) Propionate (trade name WPBG-266), 1,2-dicyclohexyl 4,4,5,5-tetramethyldifluorene n-butyltriphenylborate (trade name WPBG-300), and 2 -(9-oxo dibenzopiperan (xanthene) -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) and the like. In addition, the aforementioned product names containing "WPBG" are the product names of Wako Pure Chemical Industries, Ltd. Examples of the photoacid generator include an aromatic sulfonium salt (trade name SP-170: ADEKA), a triarylsulfonium salt (trade name CPI101A: San-Apro Ltd.), and an aromatic sulfonium salt (trade name Irgacure250: Ciba Japan). Company) and so on. In addition, the catalyst for chemically bonding the fine pore particles to each other is not limited to the photoactive catalyst and the photocatalyst generating agent, and may be, for example, a thermally active catalyst or a thermal catalyst generating agent. Examples of the catalyst for chemically bonding the fine pore particles to each other include basic catalysts such as potassium hydroxide, sodium hydroxide, and ammonium hydroxide, and acid catalysts such as hydrochloric acid, acetic acid, and oxalic acid. Of these, alkaline catalysts are preferred. The catalyst or catalyst generator for chemically bonding the fine pores to each other, for example, can be added to a sol particle liquid (such as a suspension) containing the pulverized material (fine pores) just before coating. It can be used, or it can be used as a mixed liquid in which the aforementioned catalyst or catalyst generator is mixed into a solvent. The mixed solution may be, for example, a dispersion in which a coating solution dissolved in the sol particle liquid is directly added, a solution in which the catalyst or catalyst generator is dissolved in a solvent, or the catalyst or catalyst generator is dispersed in a solvent. liquid. The solvent is not particularly limited, and examples thereof include water and a buffer solution.

[2-3. Manufacturing method of low refractive index layer and manufacturing method of optical sheet for light guide plate type liquid crystal display] Hereinafter, the manufacturing method of the low refractive index layer and optical sheet for light guiding plate type liquid crystal display of the present invention will be exemplified below. Of manufacturing method. Hereinafter, the case where the low-refractive index layer of the present invention is a polysilicon porous body formed of a silicon compound will be described below. However, the low-refractive index layer of the present invention is not limited to a polysilicon porous body. When the low-refractive index layer of the present invention is other than a polysiloxane porous body, the following explanations can be applied without mentioning otherwise.

The manufacturing method of the low-refractive index layer of the present invention includes, for example, the following steps: a precursor forming step, using the gel-containing pulverized substance-containing liquid of the present invention, to form the low-refractive index layer precursor; and a combining step to make the precursor The aforementioned pulverized material containing the aforementioned pulverized gel-containing liquid contained therein is chemically bonded to each other. The precursor may be referred to as a coating film, for example.

According to the method for producing a low-refractive index layer of the present invention, for example, a porous structure capable of exhibiting the same function as the air layer can be formed. The reason is speculated as follows, but the present invention is not limited by this speculation. The case where the low refractive index layer of the present invention is a polysilicon porous body is exemplified below.

The gel-containing pulverized material liquid of the present invention used in the aforementioned method for producing a porous polysiloxane contains the pulverized material of the silicon compound gel, so the three-dimensional structure of the gel-like silicon dioxide compound is dispersed into a three-dimensional basic structure. status. Therefore, in the method for manufacturing a polysilicone porous body, for example, if the precursor (such as a coating film) is formed by using the gel-containing pulverized material liquid, the three-dimensional basic structure is stacked to form the three-dimensional basic structure. The main void structure. That is, by using the method for manufacturing a polysilicon porous body described above, a new three-dimensional structure that is completely different from the three-dimensional structure of the silicon compound gel and is formed by the pulverized product of the three-dimensional basic structure can be formed. In addition, in the method for manufacturing a polysilicon porous body, the pulverized materials are further chemically bonded to each other, so the new three-dimensional structure can be fixed. Therefore, although the aforementioned polysiloxane porous body produced by the method for producing the aforementioned polysiloxane porous body has a structure having voids, it can still maintain sufficient strength and flexibility. The low-refractive index layer (such as a polysilicon porous body) prepared by the present invention can be used as a member using a gap in products in a wide range of fields, such as a heat-insulating material, a sound-absorbing material, an optical member, and a printing ink image receiving layer In addition, laminated films with various functions can also be produced.

The method for producing the low-refractive index layer of the present invention is mentioned before the special description, and the above description of the gel-containing pulverized liquid of the present invention can be cited.

In the step of forming the precursor of the porous body, for example, the gel-containing pulverized material-containing liquid of the present invention is applied to the substrate. The gel-containing pulverized material liquid of the present invention can be continuously formed into a film by, for example, coating the base material and drying the coating film, and then chemically bonding the pulverized materials to each other (for example, cross-linking) through the bonding step. Low-refractive-index layer with a certain degree of film strength.

The coating amount of the gel-containing pulverized material-containing liquid on the substrate is not particularly limited. For example, it can be appropriately set according to the desired thickness of the low-refractive index layer of the present invention. As a specific example, when forming the aforementioned polysilica porous body having a thickness of 0.1 to 1000 μm, the coating amount of the gel-containing pulverized material liquid on the substrate is per 1 m ^{2 of the} area of the substrate. The crushed material is 0.01 to 60,000 μg, 0.1 to 6000 μg, and 1 to 50 μg. The ideal coating amount of the gel-containing pulverized material liquid is related to, for example, the liquid concentration or the coating method, so it is difficult to make a single definition. If productivity is taken into consideration, it should be coated as thin as possible. If the coating amount is too large, for example, the possibility that the solvent is dried in a drying furnace before the solvent is volatilized becomes high. Thereby, before the nano-pulverized sol particles are settled in the solvent and deposited to form a void structure, the drying of the solvent may hinder the formation of voids, thereby greatly reducing the void ratio. On the other hand, if the coating amount is too thin, the risk of coating shrinkage (cissing) may increase due to unevenness of the substrate, variations in hydrophilicity, and the like.

After the gel-containing pulverized material-containing liquid is coated on the substrate, the porous body precursor (coating film) may be dried. The purpose of the drying process is not only to remove the solvent (the solvent contained in the gel-containing pulverized substance-containing liquid) in the porous body precursor, but also to settle and accumulate sol particles to form a void structure during the drying process. . The temperature of the drying process is, for example, 50 to 250 ° C, 60 to 150 ° C, or 70 to 130 ° C. The time of the drying process is, for example, 0.1 to 30 minutes, 0.2 to 10 minutes, or 0.3 to 3 minutes. Regarding the drying process temperature and time, for example, in view of the correlation between continuous productivity and high porosity, a low temperature and a short time are preferred. If the conditions are too severe, for example, when the substrate is a resin film, when the glass transition temperature of the substrate is near, the substrate will stretch in a drying furnace and may form a void structure 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 furnace, there may be appearance defects such as scratches when rubbing against the roller in the next step.

The drying treatment may be, for example, natural drying, heating drying, or drying under reduced pressure. The drying method is not particularly limited, and for example, a general heating mechanism can be used. Examples of the heating means include a hot air heater, a heating roller, and a far-infrared heater. Among them, under the premise of continuous industrial production, heating and drying should be used. In addition, regarding the usable solvents, when the purpose is to suppress the shrinkage stress caused by the solvent volatilization during drying and the subsequent cracking phenomenon of the low refractive index layer (the aforementioned polysiloxane porous body), the solvent having a low surface tension is used. Solvents are preferred. Examples of the aforementioned solvent include lower alcohols such as isopropyl alcohol (IPA), hexane, and perfluorohexane, but are not limited thereto.

The substrate is not particularly limited. For example, it is suitable to use a substrate made of a thermoplastic resin, a substrate made of glass, an inorganic substrate typified by silicon, a plastic such as a thermosetting resin, a semiconductor, and a carbon nanotube. The representative carbon fiber materials and the like are not limited thereto. The form of the aforementioned substrate may be a film, a sheet, or the like. Examples of the thermoplastic resin include polyethylene terephthalate (PET), acrylic acid, cellulose acetate propionate (CAP), cycloolefin polymer (COP), triacetate (TAC), and polynaphthalene dicarboxylic acid. Ethylene glycol (PEN), polyethylene (PE), polypropylene (PP), etc.

In the method for manufacturing a low-refractive index layer according to the present invention, the bonding step is a step of chemically bonding the pulverized materials contained in the precursor (coating film) of the porous body to each other. By the aforementioned bonding step, for example, the three-dimensional structure of the pulverized material of the precursor of the porous body can be fixed. When the conventional sintering is used for immobilization, for example, the dehydration condensation of the silanol group is excited by performing a high temperature treatment of 200 ° C or higher to form a siloxane bond. In the foregoing combining step of the present invention, various additives that catalyze the above-mentioned dehydration condensation reaction are reacted, for example, when the substrate is a resin film, the aforementioned substrate is not damaged, and the temperature can be lowered around 100 ° C. At the drying temperature and a short processing time of only a few minutes, a void structure is continuously formed and fixed.

The method for performing the chemical bonding is not particularly limited. For example, it can be appropriately determined according to the type of the gel (such as a silicon compound gel). As a specific example, the chemical bonding can be performed, for example, by chemical cross-linking of the pulverized materials with each other, and other considerations such as adding inorganic particles such as titanium oxide to the pulverized materials can make the inorganic particles and The pulverized material is chemically cross-linked. In addition, there is a case where a biocatalyst such as an enzyme is carried, or other parts different from the active sites of the catalyst are chemically cross-linked with the crushed material. Therefore, the present invention is not only limited to the low-refractive index layer formed by the aforementioned sol particles, but can also be extended to apply to organic-inorganic mixed low-refractive index layers, host-guest low-refractive index layers, etc.

The aforementioned bonding step can be performed, for example, by a chemical reaction in the presence of a catalyst in accordance with the type of the pulverized material of the aforementioned gel (such as a silicon compound gel). The chemical reaction of the present invention is preferably a dehydration condensation reaction of a residual silanol group contained in the pulverized material of the aforementioned silicon compound gel. By using the aforementioned catalyst to promote the reaction between the hydroxyl groups of the silanol group, continuous film formation that hardens the void structure in a short time can be achieved. The aforementioned catalysts include, but are not limited to, alkaline catalysts such as potassium hydroxide, sodium hydroxide, and ammonium hydroxide, and acid catalysts such as hydrochloric acid, acetic acid, and oxalic acid. The catalyst for the aforementioned dehydration condensation reaction is particularly preferably a basic catalyst. It is also suitable to use a photoacid-generating catalyst or a photobase-generating catalyst that exhibits catalytic activity by irradiating light (for example, ultraviolet rays). The photoacid-generating catalyst and the photobase-generating catalyst are not particularly limited, as described above. The catalyst is the same as described above, and it is suitable to be added to the sol particle liquid containing the pulverized material just before coating, or it may be used as a mixed liquid in which the catalyst is mixed in a solvent. The mixed solution may be, for example, a coating solution dissolved in the sol particle liquid, a solution in which the catalyst is dissolved in a solvent, or a dispersion in which the catalyst is dispersed in a solvent. The solvent is not particularly limited, and examples thereof include water and a buffer solution.

Further, for example, a cross-linking assistant may be further added to the gel-containing liquid of the present invention to indirectly bond the pulverized matter of the gel. The cross-linking auxiliary agent intervenes between the particles (the above-mentioned pulverized material), so that the particles and the cross-linking auxiliary agent interact or combine with each other, so that the particles that are slightly separated from each other can also be bonded to each other, which can effectively improve the strength . The crosslinking assistant is preferably a polycrosslinking silane monomer. The polycrosslinked silane monomer specifically has, for example, an alkoxysilyl group of 2 or more and 3 or less, and the chain length between the alkoxysilyl groups may be 1 or more and 10 or less, and may contain elements other than carbon. The aforementioned cross-linking assistants can be exemplified by: bis (trimethoxysilyl) ethane, bis (triethoxysilyl) ethane, bis (trimethoxysilyl) methane, bis (triethoxysilyl) methane, bis (Triethoxysilyl) propane, bis (trimethoxysilyl) propane, bis (triethoxysilyl) butane, bis (trimethoxysilyl) butane, bis (triethoxysilyl) pentane, Bis (trimethoxysilyl) pentane, bis (triethoxysilyl) hexane, bis (trimethoxysilyl) hexane, bis (trimethoxysilyl) -N-butyl-N-propyl-ethyl Alkane-1,2-diamine, ginseng- (3-trimethoxysilylpropyl) trimeric isocyanate, ginseng- (3-triethoxysilylpropyl) trimeric isocyanate, and the like. The addition amount of the cross-linking auxiliary is not particularly limited, and for example, it is 0.01 to 20% by weight, 0.05 to 15% by weight, or 0.1 to 10% by weight with respect to the weight of the pulverized product of the silicon compound.

The chemical reaction in the presence of the catalyst can be performed, for example, by: irradiating or heating the coating film containing the catalyst or catalyst generator previously added to the gel-containing pulverized material liquid; or Light irradiation or heating is performed after spraying the catalyst onto the coating film; or light irradiation or heating is performed after spraying the catalyst or catalyst generator. For example, when the catalyst is a photoactive catalyst, the microporous particles can be chemically bonded to each other by light irradiation to form the polysilica porous body. When the catalyst is a thermally active catalyst, the microporous particles can be chemically bonded to each other by heating to form the polysilica porous body. The light irradiation amount (energy) of the light irradiation is not particularly limited, and is, for example, 200 to 800 mJ / cm ² , 250 to 600 mJ / cm ^2, or 300 to 400 mJ / cm ² in terms of ＠ 360nm. From the standpoint of preventing the effect of degradation of light absorption by the catalyst generator from progressing due to insufficient irradiation amount, the cumulative light amount of 200 mJ / cm ² or more is preferred. In addition, from the viewpoint of preventing damage to the base material under the low-refractive index layer from generating thermal wrinkles, it is preferable to use a cumulative light amount of 800 mJ / cm ² or less. The wavelength of the light irradiated by the light is not particularly limited, and is, for example, 200 to 500 nm and 300 to 450 nm. The light irradiation time of the light irradiation is not particularly limited, and is, for example, 0.1 to 30 minutes, 0.2 to 10 minutes, and 0.3 to 3 minutes. The conditions for the heat treatment are not particularly limited. The heating temperature is, for example, 50 to 250 ° C., 60 to 150 ° C., or 70 to 130 ° C., and the heating time is, for example, 0.1 to 30 minutes, 0.2 to 10 minutes, or 0.3 to 3 minutes. In addition, the usable solvent is, for example, a solvent having a low surface tension when the purpose is to suppress shrinkage stress caused by solvent volatilization during drying and subsequent cracking of the low refractive index layer. Examples include, but are not limited to, lower alcohols such as isopropyl alcohol (IPA), hexane, and perfluorohexane.

The low-refractive index layer (for example, a polysilicon porous body) of the present invention can be manufactured 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. The low-refractive index layer of the present invention which is a polysilicon porous body may be hereinafter referred to as a "polysilicon porous body of the present invention".

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 applied (coated) on the low refractive index layer of the present invention to form the aforementioned adhesive layer. Alternatively, the side of the adhesive layer such as an adhesive tape laminated with the aforementioned adhesive layer on the substrate may be laminated to the low refractive index layer of the present invention, thereby forming the aforementioned on the low refractive index layer of the present invention. Adhesive layer. At this time, the substrate such as the aforementioned adhesive tape may be maintained in a state of being directly bonded, or may be peeled from the aforementioned adhesive layer. In particular, as described above, by making the base material without a base material (without a base material) by peeling the base material from the low refractive index, the thickness can be significantly reduced, and the increase in thickness of devices and the like can be suppressed. In the present invention, the "adhesive" and "adhesive layer" refer to a solvent or layer premised on the re-peeling of the adherend. In the present invention, the "adhesive" and "adhesive layer" refer to a solvent or a layer that is not premised on the re-peeling of the adherend. However, in the present invention, "adhesive" and "adhesive" are not clearly distinguishable, and "adhesive layer" and "adhesive layer" are not clearly distinguishable. In the present invention, the adhesive or the adhesive forming the adhesive layer is not particularly limited, and for example, a general adhesive or an adhesive can be used. Examples of the adhesive or adhesive include polymer-based adhesives such as acrylic, vinyl alcohol-based, polysiloxane-based, polyester-based, polyurethane-based, and polyether-based adhesives, and rubber-based adhesives. Moreover, the adhesive agent which consists of water-soluble crosslinking agents, such as a vinyl alcohol polymer, such as glutaraldehyde, melamine, and oxalic acid, etc. are mentioned. These adhesives and adhesives may be used singly or in combination (for example, mixing, laminating, etc.). As described above, the low-refractive index layer can be protected from physical damage (especially abrasion) by the adhesive layer. The adhesive layer is preferably an optical sheet for a light guide plate type liquid crystal display without a substrate (without a substrate), which is excellent in pressure resistance and will not crush the low refractive index layer, but it is not particularly limited. . The thickness of the adhesive layer is not particularly limited, and is, for example, 0.1 to 100 μm, 5 to 50 μm, 10 to 30 μm, or 12 to 25 μm.

The low-refractive index layer of the present invention obtained as described above can further be laminated with the first optical film and the second optical film to produce an 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, for example, as described above, with the adhesive layer (adhesive or adhesive) interposed therebetween.

Based on the efficiency, the above-mentioned constituent elements of the optical sheet for a light guide plate type liquid crystal display of the present invention can be laminated by, for example, continuous processing using a long film (so-called roll to roll, etc.), When the base material is a molded article, an element, or the like, it may be laminated after being subjected to batch processing.

The following is a method for manufacturing a low-refractive index layer and a light guide plate-type optical sheet for a liquid crystal display of the present invention using a resin film substrate for transfer (hereinafter sometimes referred to simply as a "substrate"). for example. In addition, the manufacturing method shown is an example, and it is not limited to these.

An example of the process of manufacturing the low-refractive-index layer of this invention and the optical sheet for light-guide-plate-type liquid crystal displays of this invention using the said base material is shown in the sectional view of FIG. In FIG. 3, the method for forming the aforementioned low refractive index layer includes the following steps: a coating step (1), applying the aforementioned gel-containing pulverized material liquid 20 '' of the present invention on a substrate 10; a coating film forming step (drying) Step) (2), drying the gel-containing pulverized material liquid 20 "to form a coating film 20 ', which is a precursor layer of the aforementioned low refractive index layer; and a chemical treatment step (such as a crosslinking treatment) Step) (3): The coating film 20 'is subjected to a chemical treatment (such as a cross-linking treatment) to form a 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 low-refractive index layer may suitably include steps other than the steps (1) to (3) described above, and it is not necessary to have any problem. In addition, as shown in the figure, an optical sheet for a light guide plate type liquid crystal display including a laminated body can be manufactured by performing the following steps, and the laminated body is directly laminated with the adhesive layer 30 on one or both sides of the low refractive index layer 20 : 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 Step (6), peeling and removing the substrate 10 from the low-refractive index layer 20; and adhesive layer coating step (7), applying another adhesive layer on the surface of the low-refractive index layer 20 on the side of the peeled substrate 10 30; and a covering step (8), covering the other adhesive layer 30 with another optical film 40. The two optical films 40 can be regarded as either one corresponding to the first optical film and the other corresponding to the second optical film. The adhesive layer 30 having the first optical film and the low-refractive index layer 20 adhered (adhered) can be regarded as the first adhesive layer. Next (adhesive) the adhesive layer 30 having the second optical film and the low refractive index layer 20 can be regarded as the second adhesive layer. In addition, FIG. 3 shows a method of separately performing the adhesive layer coating step (4) and the covering step (5). However, an adhesive film 30 (such as an optical film) previously provided with an optical film 40 may be used. 40 and the adhesive layer 30 as an integrated adhesive tape) are attached to the low refractive index layer 20, thereby performing the adhesive layer coating step (4) and the covering step (5) simultaneously. The same applies to the adhesive layer coating step (7) and the covering step (8). In addition, the method for forming an optical sheet for a light guide plate-type liquid crystal display may suitably include steps other than the steps (1) to (8), and it is not necessary to include them. For another example, in FIG. 3, a separating member may be attached to replace the optical film 40 to protect the adhesive layer 30. For example, the first optical film or the second optical film may be attached to the adhesive layer 30 after the separation member of the protective adhesive layer 30 is peeled off to manufacture the optical sheet for a light guide plate type liquid crystal display of the present invention. material. For another example, in FIG. 3, the aforementioned steps (1) to (3) may be performed directly on the first optical film or the second optical film 40 without using the substrate 10 and not on the substrate 10, so as to form the aforementioned low refractive index. Rate layer. At this time, the optical film 40 and the low-refractive index layer 20 used for the substrate 10 are replaced without being laminated with the adhesive layer 30 interposed therebetween.

In the aforementioned coating step (1), the coating method for the gel-containing pulverized liquid 20 "is not particularly limited, and a general coating method can be adopted. The aforementioned coating method may be, for example, a slot die method, a reverse gravure coat method, a micro gravure method (micro gravure coat method), Dipping method (dip coating method), spin coating method, brush coating method, roll coating method, flexographic printing method, wire rod coating method, spray coating method, extrusion coating method, curtain coating method, reverse Coating method, etc. Among these, from the viewpoints of productivity and smoothness of the coating film, an extrusion coating method, a curtain coating method, a roll coating method, a micro gravure coating method, and the like are preferred. The coating amount of the gel-pulverized material-containing liquid 20 "is not particularly limited, and it can be appropriately set such that the porous structure (low-refractive index layer) 20 can have an appropriate thickness. 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 gel-containing pulverized material-containing liquid 20 ″ is dried (that is, the dispersion medium contained in the gel-containing pulverized material-containing liquid 20 ″ is removed) to form a coating film (precursor layer) 20 ′. . The conditions for the drying treatment are not particularly limited, as described above.

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

Next, FIG. 4 schematically shows an example of a coating device of a slit die coating method and a method of forming the aforementioned low refractive index layer using the coating device. In addition, FIG. 4 is a cross-sectional view, but hatching is omitted for easy viewing.

As shown in the figure, each step of the method using the apparatus is performed while conveying the substrate 10 in one direction by a roller. 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 output from the sending-out roller 101 and conveyed at the same time. After the coating roller 102 performs the coating step (1) for coating the gel-containing pulverized material-containing liquid 20 "of the present invention on the substrate, then in the oven area Within 110, a transition is made to the drying step (2). In the coating apparatus of FIG. 4, a pre-drying step is performed before the drying step (2) after the coating step (1). The pre-drying step does not require heating and can be performed at room temperature. In the drying step (2), a heating mechanism 111 is used. As described above, the heating mechanism 111 is preferably a hot air heater, a heating roller, a far-infrared heater, or the like. For example, the drying step (2) can be divided into a plurality of steps, and the closer to the subsequent drying step, the higher the drying temperature.

After the drying step (2), a chemical treatment step (3) is performed in the chemical treatment zone 120. In the chemical treatment step (3), for example, when the dried coating film 20 'contains a photoactive catalyst, light is irradiated with a lamp (light irradiation means) 121 disposed above and below the substrate 10. Alternatively, for example, when the dried coating film 20 'contains a thermally active catalyst, a hot air heater (heating mechanism) is used instead of the lamp (light irradiation device) 121, and the hot air heater 121 disposed above and below the base material 10 is used to separate the base material. 10 热。 10 heating. By this cross-linking treatment, chemical bonding of the pulverized materials in the coating film 20 'is initiated, and the low refractive index layer 20 is hardened and strengthened. In addition, although illustration is omitted, the steps (4) to (8) in FIG. 3 can be performed by a roll to roll method to manufacture the optical sheet for a light guide plate type liquid crystal display. Then, the obtained optical sheet for a light guide plate type liquid crystal display is taken up by a take-up roll 105.

An example of a coating apparatus for a micro gravure method (micro gravure coating method) and a method for forming the porous structure using the micro gravure method (micro gravure coating method) is shown schematically in FIG. 5. In addition, although the same figure is a cross-sectional view, hatching has been omitted for easy viewing.

As shown in the figure, each step of the method using the apparatus is performed while conveying the substrate 10 in one direction by a roller member in the same manner 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, the substrate 10 is conveyed while being conveyed from the sending-out roller 201, and the coating step (1) is performed, that is, the gel-containing pulverized material-containing liquid 20 ″ of the present invention is coated on the substrate 10. As shown in the figure, the gel-containing pulverized liquid 20 "is applied using a liquid storage area 202, a doctor knife 203, and a microgravure 204. Specifically, the gel-containing pulverized material liquid 20 "stored in the liquid storage area 202 is attached to the surface of the microgravure 204, and then controlled to a predetermined thickness by a doctor blade 203, and simultaneously coated on the substrate 10 with the microgravure 204 In addition, the micro gravure 204 is an example, and is not limited thereto, and any other coating mechanism may be used.

This is followed by a drying step (2). Specifically, as shown in the figure, the substrate 10 coated with the gel-containing pulverized liquid 20 "is transported in the oven region 210, and is heated and dried by a heating mechanism 211 in the oven region 210. The heating mechanism 211 may be Figure 4 is the same. Also, for example, by dividing the oven area 210 into multiple blocks, the drying step (2) can be divided into multiple steps, so that the drying temperature becomes higher with the subsequent drying step. In the drying step ( 2) Then, a chemical treatment step (3) is performed in the chemical treatment zone 220. In the chemical treatment step (3), for example, when the dried coating film 20 'contains a photoactive catalyst, it is disposed on the substrate 10 upper and lower lamps (light irradiation means) 221 for light irradiation. Or, for example, when the dried coating film 20 'contains a thermally active catalyst, a hot air heater (heating means) is used instead of the lamp (light irradiation means) 221. The substrate 10 is heated by a hot air heater (heating mechanism) 221 disposed below the substrate 10. By this cross-linking treatment, chemical bonding between the aforementioned pulverized materials in the coating film 20 'is initiated, and a low refractive index can be formed. Layer 20.

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

[3. Void layer] The case where the low refractive index layer of the present invention is a void layer (the void layer of the present invention) is exemplified below.

The void layer of the present invention may have, for example, a void ratio of 35 vol% 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 to this.

The 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 void layer of the present invention may be, for example, a high void layer having a void ratio of 60% by volume or more.

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

(Measurement method of porosity) If the layer to be measured for porosity is a single layer and contains only voids, the ratio (volume ratio) of the constituent material of the layer to the air can be measured by conventional methods (such as measuring weight and volume to calculate density). Since it is calculated, the porosity (volume%) can be calculated from this. Since the refractive index has a correlation with the porosity, the porosity can also be calculated from the value of the refractive index as a layer, for example. Specifically, for example, the porosity can be calculated from the value of the refractive index measured by an ellipsometer using Lorentz-Lorenz's formula.

The void layer of the present invention can be produced, for example, as described above, by chemical bonding of pulverized gel (fine-pored particles). At this time, the voids of the void layer can be conveniently divided into the following three types (1) to (3). (1) The voids in the raw gel itself (inside the particles) (2) The voids in the gel pulverized substance unit (3) The voids between the pulverized substances generated by the accumulation of the pulverized gel

The voids in the above (2) may be formed when each particle group generated by pulverizing the gel is regarded as a clump (block) regardless of the size and size of the pulverized gel (fine-pored particles). The voids formed inside each block are different from those described in (1) above during crushing. In addition, the voids in the above (3) are voids generated when the size, size, and the like of the pulverized gel (fine-pored particles) become uneven during pulverization (for example, non-media pulverization, etc.). The void layer of the present invention has an appropriate porosity and peak pore diameter, for example, because it has the voids (1) to (3).

The peak pore diameter may be, for example, 5 nm or more, 10 nm or more, or 20 nm or more, and may be 50 nm or less, 40 nm or less, or 30 nm or less. In the void layer, if the peak pore diameter is too large when the void ratio is high, light will be scattered and become opaque. In the present invention, the lower limit value of the peak pore diameter of the void layer is not particularly limited, but if the peak pore diameter is too small, it is difficult to increase the void ratio, so the peak pore diameter should not be too small. In the present invention, the peak pore diameter can be measured by, for example, the following method.

(Measurement method of peak pore size) Using a pore size distribution / specific surface area measuring device (BELLSORP MINI / Micromeritics Japan), nitrogen adsorption was used to obtain BJH drawings, BET drawings, and isothermal adsorption lines, and the results obtained therefrom Calculate the peak pore diameter.

The thickness of the void layer of 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, and may be 10,000 nm or less, 5000 nm or less, or 2000 nm or less.

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

The void layer of the present invention uses the pulverized product of the porous body gel, so the three-dimensional structure of the porous body gel is destroyed, and a new three-dimensional structure that is different from the porous body gel is formed. As such, the void layer of the present invention can be formed into a layer having a high porosity nanometer grade by forming a layer having a new pore structure (new void structure) that cannot be obtained with the layer formed from the porous body gel described above. Interstitial layer. In addition, in the void layer of the present invention, for example, when the void layer is a polysilicon porous body, for example, the pulverized materials can be chemically bonded to each other while adjusting the number of siloxane bond functional groups of the silicon compound gel. In addition, after a new three-dimensional structure is formed as a precursor of the void layer, chemical bonding (such as cross-linking) is performed in a bonding step. Therefore, when the void layer of the present invention is a functional porous body, for example, Although it has a void structure, it can 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 material containing a porous body gel, and the pulverized materials are in a chemically bonded state. In the void layer of the present invention, the chemical bonding (chemical bond) form of the pulverized materials is not particularly limited, and specific examples of the chemical bonding include cross-linking bonding and the like. The method of chemically bonding the pulverized materials to each other is as described in detail in the method for manufacturing the void layer.

The cross-linking bond is, for example, a siloxane bond. Examples of the siloxane bond include a T2 bond, a T3 bond, and a T4 bond. When the polysiloxane porous body of the present invention has a siloxane bond, for example, it may have any one of the bonds, may have any two of the bonds, or may have all three of the bonds. In the aforementioned siloxane bond, the more the ratio of T2 and T3 is, the more flexible it is, and the more original properties of the gel can be expected, but the film strength becomes weaker. On the other hand, the T4 ratio in the siloxane bond is large, and although the strength of the film is easily developed, the void size is reduced and the flexibility is weakened. Therefore, for example, the T2, T3, and T4 ratio should be adjusted according to the application.

[Chemical Formula 5]

When the void layer of the present invention has the aforementioned siloxane bond, 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].

The void layer of the present invention is preferably, for example, when the silicon atoms contained therein are siloxane bonded. As a specific example, the ratio of unbonded silicon atoms (that is, residual silanols) in the total silicon atoms contained in the aforementioned polysilica porous body is, for example, less than 50%, 30% or less, and 15% or less.

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

(Sectional SEM Observation of the Void Layer) In the present invention, the morphology of the void layer can be observed and analyzed with a SEM (scanning electron microscope). Specifically, for example, the aforementioned void layer can be subjected to FIB processing under cooling (acceleration voltage: 30 kV), and FIB-SEM (made by FEI Corporation: trade name Helios NanoLab600, acceleration voltage: 1 kV) can be used for the obtained cross-sectional sample to observe A cross-section electron 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 a BET test method. Specifically, a 0.1 g sample (a void layer of the present invention) was placed in a capillary tube of a pore distribution / specific surface area measuring device (a brand name of BELLSORP MINI / Micromeritics Japan), and then reduced at room temperature for 24 hours. Pressure drying to degas the gas in the void structure. Then, nitrogen was adsorbed on the sample, and a BET chart, a BJH chart, and an adsorption isotherm were drawn to calculate a pore distribution. This allows the gap size to be evaluated.

The void layer of the present invention has a scratch resistance of 60 to 100%, for example, using BEMCOT (registered trademark), which shows film strength. Because the present invention has such strength, it has excellent scratch resistance in various processes. The present invention has, for example, wound resistance in a production process when a product film is wound up and disposed after the aforementioned void layer is produced. On the other hand, in the void layer of the present invention, for example, instead of reducing the porosity, the catalyst reaction in the heating step described later can be used to increase the particle size of the pulverized material of the silicon compound gel and the pulverized material combined with The binding force of the neck. With this, 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 abrasion resistance is, for example, 60% or more, 80% or more, 90% or more, and the upper limit is, for example, 100% or less, 99% or less, or 98% or less, and the ranges are, for example, 60 to 100%, 80 to 99%, 90 ~ 98%.

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

(Evaluation of abrasion resistance) (1) A space-shaped object having a diameter of about 15 mm was sampled from a space layer (the space layer of the present invention) coated and formed on an acrylic film. (2) Next, the sample was identified by fluorescent X-rays (manufactured by Shimadzu Corporation: ZSX Primus II), and the Si coating amount (Si ₀ ) was measured. Then, with respect to the void layer on the acrylic film, the void layer was cut into a size of 50 mm × 100 mm from the periphery of the sample and fixed to a glass plate (thickness 3 mm), and then a sliding test was performed using BEMCOT (registered trademark). The sliding conditions were set to 10 reciprocating weights of 100 g. (3) Sampling and fluorescent X measurement were performed from the void layer that had finished sliding in the same manner as in (1) above, and the residual amount of Si (Si ₁ ) after the abrasion test was measured. The abrasion resistance is defined by the Si residual ratio (%) before and after the BEMCOT (registered trademark) test, and can be expressed 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, for example, 100 times of folding resistance obtained by the MIT test showing flexibility. Since the present invention has such flexibility, it has good disposability, such as winding and manufacturing.

The lower limit of the number of times of folding resistance is, for example, 100 times or more, 500 times, or 1,000 times or more. The upper limit is not particularly limited. For example, the upper limit is 10,000 times or less. .

The aforementioned flexibility refers to a material's easy deformability. The number of times of folding resistance obtained by the MIT test can be measured, for example, by the following method.

(Folding test evaluation) The above-mentioned void layer (the void layer of the present invention) was cut into a short signature of 20 mm × 80 mm, and then installed on a MIT folding tester (manufactured by TESTER SANGYO CO ,. LTD .: BE-202) And attach a load of 1.0N. The clamping head for enclosing the gap layer uses R2.0mm, and the number of times of folding resistance is 10,000 times at most, and the number of times of breaking the gap layer is regarded as the number of folding resistance.

In the void layer of the present invention, the film density indicating 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, and 15 g / cm ³ or more. 50 g / cm ³ or less, 40 g / cm ³ or less, 30 g / cm ³ or less, 2.1 g / cm ³ or less, and the ranges are, for example, 5 to 50 g / cm ³ , 10 to 40 g / cm ³ , 15 to 30 g / cm ³ , 1 ~ 2.1g / cm ³ .

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

(Evaluation of film density) After forming a void layer (the void layer of the present invention) on an acrylic film, the X-ray reflectance of the total reflection region was measured using an X-ray diffraction device (manufactured by RIGAKU: RINT-2000). After the Intensity and 2θ are adjusted, the porosity (P%) is calculated from the critical angle of the total reflection of the void layer and the substrate. The film density can be expressed 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-cell foam structure having a continuous pore structure. The open foamed structure indicates, for example, a state in which the pore structures are connected in a three-dimensional manner in the void layer, and the internal voids of the pore structure are connected together. When the porous body has an open foam structure, it can increase the porosity in the whole, but when closed-cell particles such as hollow silica are used, the openness cannot be formed. Foam structure. In contrast, the void layer of the present invention has a three-dimensional tree structure because the sol particles (the pulverized porous body gel forming sol) have a three-dimensional tree structure. By the sedimentation and accumulation of the dendritic particles, an open foam structure can be easily formed. In addition, it is preferable that the void layer of the present invention forms a monolithic structure having an open foam structure having a plurality of fine pore distributions. The monolithic structure refers to a hierarchical structure in which, for example, a structure having fine voids having a nanometer size and an open foaming structure formed by aggregating the same nanovoids exists. When the monolithic structure is formed, for example, the film strength is imparted with fine voids and the high open porosity is provided with coarse open foamed voids, so that both film strength and high void fraction can be achieved. In order to form these monolithic structures, it is important, for example, to control the pore distribution of the generated void structure in the porous body gel at a stage before crushing into the crushed material. When the porous body gel is pulverized, for example, the monolithic structure can be formed by controlling the particle size distribution of the pulverized material to a desired size.

In the void layer of the present invention, there is no particular limitation on the elongation rate of the crack formation exhibiting flexibility, and the lower limit thereof is, for example, 0.1% or more, 0.5% or more, and 1% or more, and the upper limit thereof is, for example, 3% or less. The ranges of the crack formation elongation are, for example, 0.1 to 3%, 0.5 to 3%, and 1 to 3%.

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

(Evaluation of the crack formation elongation) After forming a void layer (the void layer of the present invention) on an acrylic film, a 5 mm × 140 mm short signature was sampled. Next, the sample was clamped in a tensile tester (manufactured by Shimadzu Corporation: AG-Xplus) so that the distance between the clamps was 100 mm, and then the tensile test was performed at a tensile speed of 0.1 mm / s. Carefully observe the aforesaid sample in the test, and end the test at the time point when a crack is formed on the part of the sample, and use the elongation (%) at the time point of crack formation as the crack formation elongation.

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

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

(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 Research Institute: HM-150), and the haze was measured. The haze value can be calculated by the following formula. Haze (%) = [diffusive transmittance (%) / total light transmittance (%)] × 100 (%)

Generally, the aforementioned refractive index refers to the ratio of the transmission speed of light in a vacuum to the wavefront to the propagation speed in a medium, and is called the refractive index of the medium. The refractive index of the polysilica 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, 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 or more and 1.3 or less, 1.05 or more and less than 1.3, 1.05 or more and 1.25 or less, 1.06 or more and less than 1.2, and 1.07 or more and 1.15 or less.

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

(Evaluation of refractive index) After forming a void layer (the void layer of the present invention) on an acrylic film, it was cut into a size of 50 mm × 50 mm and bonded to the surface of a glass plate (thickness: 3 mm) with an adhesive layer. A central portion (about 20 mm in diameter) of the back surface of the glass plate was blackened with a black marker to prepare a sample that was not reflected on the back surface of the glass plate. 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 of the present invention is not particularly limited. The lower limit thereof is, for example, 0.05 μm or more and 0.1 μm or more. The upper limit is, for example, 1000 μm or less and 100 μm or less.

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

The method for producing the void layer of the present invention is not particularly limited, and for example, it can be produced by the aforementioned method for producing the void layer. Examples

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

[Reference Example 1] First, gelation of a silicon compound (the following step (1)) and aging step (the following step (2)) 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, and (6) gel pulverization step are performed thereafter to obtain a low refractive index layer. Formation coating liquid (liquid containing pulverized gel). In addition, in this reference example, as described below, the following (3) form control step is performed with steps different from the following step (1). However, the present invention is not limited to this. For example, the following (3) form control step may be performed in the following step (1).

(1) Gelation of silicon compound MTMS of 9.5 kg of precursor of silicon compound was dissolved in 22 kg of DMSO. After adding 5 kg of a 0.01 mol / L oxalic acid aqueous solution to the mixed solution, stirring was performed at room temperature for 120 minutes, and MTMS was hydrolyzed to produce ginsyl (hydroxy) methylsilane.

After adding 3.8 kg of 28% ammonia water and 2 kg of pure water to 55 kg of DMSO, the aforementioned hydrolyzed mixed solution was further added and stirred at room temperature for 60 minutes. The liquid after stirring for 60 minutes was poured into a stainless steel container having a length of 30 cm × width 30 cm × height 5 cm and was left at room temperature to gelate the ginsyl (hydroxy) methylsilane to obtain a gel-like silicon compound. .

(2) Maturation step The gelatinous silicon compound obtained by performing the aforementioned gelation treatment was incubated at 40 ° C for 20 hours, and then subjected to an aging treatment to obtain the aforementioned cuboid-shaped agglomerate gel. Since the amount of DMSO (high boiling point solvent above 130 ° C) used in the raw material accounts for about 83% by weight of the entire raw material, it can be seen that the gel contains 50% by weight or higher boiling point solvent at 130 ° C or higher. In addition, since the amount of MTMS (a monomer constituting the gel constituting unit) in the raw material accounts for about 8% by weight of the entire raw material, it can be seen that the gel is hydrolyzed by the monomer (MTMS) constituting the gel constituting unit. The content of the solvent (in this case, methanol) having a boiling point lower than 130 ° C is 20% by weight or less.

(3) Morphology control step On the gel synthesized in the aforementioned stainless steel container of 30 cm x 30 cm x 5 cm by the above steps (1) and (2), water for replacing the solvent was poured. Next, the gel was slowly inserted from above into the cutting blade of the cutting jig in the stainless steel container, and the gel was cut into a rectangular parallelepiped having a size of 1.5 cm × 2 cm × 5 cm.

(4) Solvent replacement step Next, the solvent replacement step is performed in the following manner (4-1) to (4-3).

(4-1) After the "(3) morphology control step", the gel-like silicon compound is immersed in 8 times the weight of the gel-like silicon compound in water, and slowly with only water convection. Stir for 1h. After 1 h, the water was exchanged with the same amount of water and stirred for another 3 h. After that, water was exchanged again, and then slowly stirred at 60 ° C while heating for 3h.

(4-2) After (4-1), exchange water for 4 times the weight of isopropyl alcohol of the aforementioned gelatinous silicon compound, and also stir at 60 ° C and heat for 6h.

(4-3) After (4-2), isopropyl alcohol is exchanged for isobutanol of the same weight, and the same is heated at 60 ° C for 6 hours to replace the solvent contained in the aforementioned gel-like silicon compound with isobutyl alcohol. alcohol. The void layer manufacturing gel of the present invention is produced by the method described above.

(5) Concentration measurement (concentration management) and concentration adjustment steps After the solvent replacement step of the above (4), the block-shaped gel is taken out, and the solvent attached to the periphery of the gel is removed. Then, the concentration of the solid content in one gel block was determined by the weight drying method. At this time, in order to obtain the reproducibility of the measured value, the six blocks taken out at random were measured, and the average value and the difference between the values were calculated. At this time, the average value of the solid content concentration (gel concentration) in the gel was 5.20% by weight, and the variation in the aforementioned gel concentration values in the six gels was within ± 0.1%. Based on the measured value, an isobutanol solvent was added to adjust so that the concentration of the gel solid content (gel concentration) was about 3.0% by weight.

(6) Gel pulverization step The gel (gel-like silicon compound) after the concentration measurement (concentration management) and the concentration adjustment step (5) is performed by continuous emulsification and dispersion (Pacific Engineering Company, Milder MDN304 type), and the second pulverization stage uses two stages of high-pressure non-media pulverization (SUGINO MACHINE Ltd., Star Burst HJP-25005 type) for pulverization. This pulverization treatment was performed on a gel containing 43.4 kg of the gel containing the gel-like silicon compound substituted with the solvent, and 26.6 kg of isobutanol was weighed, and then circulated in the first pulverization stage for 20 minutes, and the second pulverization stage was performed. The crushing pressure is 100 MPa. In this way, an isobutanol dispersion (a gel-containing pulverized liquid) in which nano-sized particles (the pulverized product of the gel) are dispersed is prepared.

The solid content concentration (gel concentration) of the liquid (high-viscosity gel pulverization solution) was measured after the first pulverization step (coarse pulverization step) and before the second pulverization step (nano pulverization step). 3.01% by weight was obtained. After the first pulverization step (coarse pulverization step) and before the second pulverization step (nano pulverization step), the volume average particle size of the pulverized material of the gel is 3 to 5 μm, and the shear viscosity of the liquid is 4,000. mPa ・ s. At this time, the high-viscosity gel pulverized liquid has a high viscosity, so it can be treated as a homogeneous liquid without solid-liquid separation. Therefore, the measured value after the first pulverization step (coarse pulverization step) can be directly used. In addition, after the second pulverization step (nano pulverization step), the volume average particle diameter of the pulverized material of the gel is 250 to 350 nm, and the shear viscosity of the liquid is 5 m to 10 mPa · s. In addition, after the second pulverization step (nano pulverization step), the solid content concentration (gel concentration) of the liquid (gel-containing pulverized product liquid) was measured again, and as a result, 3.01% by weight was obtained, which was the same as the first pulverization. It does not change after the stage (coarse crushing step).

In this reference example, the average particle size of the pulverized material (sol particles) of the gel after the first pulverization stage and after the second pulverization stage is based on a dynamic light scattering Nanotrac particle size analyzer (Nikkiso equipment Company system, brand name UPA-EX150)). In this embodiment, the shear viscosity of the liquid after the first pulverization stage and after the second pulverization stage are confirmed with a vibration viscosity measuring machine (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 gel-containing pulverized material liquid, the functional group (silanol group) constituting the unit monomer was measured (calculated) for the absence of The ratio of the functional groups (residual silanol groups) contributing to the cross-linking structure in the gel was measured as a result of 11 mol%. The ratio of the functional group (residual silanol group) that does not contribute to the cross-linked structure in the gel is measured by measuring the solid NMR (Si-NMR) after drying the gel, and the peak value of the NMR is measured. The ratio is calculated from the residual silanol groups that do not contribute to the crosslinked structure.

The coating liquid (containing a pulverized gel-containing liquid) for forming a void layer of the present reference example (Reference Example 1) was produced by the above method. The peak pore diameter of the pulverized gel (fine-pored particles) in the coating liquid (gel-containing pulverized liquid) for forming a void layer was measured by the method described above, and it was 12 nm.

[Example 1] 3 g of the coating solution for forming a low refractive index layer prepared in Reference Example 1 was added with a mixed photobase generator (WPBG266 [Wako Pure Chemical Industries, Ltd.]: 1.5% concentration MIBK solution) 0.36 g, 0.11 g of bis (trimethoxysilyl) ethane (TCI) (5% concentration MIBK solution), and apply the obtained liquid to a 100 μm alicyclic structure resin film (Japan Zeon Corporation, product A low refractive index layer (refractive index: 1.18, porosity: 59% by volume) having a film thickness of about 800 nm was formed on a substrate (substrate film) composed of “ZEONOR: ZF16 film”) and dried. Next, UV irradiation (300 mJ) was performed from the low-refractive-index layer side, and then an adhesive (first adhesive layer) with a separator (75 μm) with a thickness of 12 μm was bonded to the low-refractive-index layer. Then, the alicyclic structure-containing resin film (substrate film) is peeled from the integrated article of the adhesive (adhesive layer) and the low refractive index layer. Thereafter, another 5 μm-thick adhesive (second adhesive layer) was further attached to the surface on which the substrate film had been peeled off, and a total thickness (overall thickness) of about 18 μm was obtained. Adhesive sheet of refractive index layer. The total thickness (overall thickness) refers to the total thickness of the laminated body [excluding the separator] of the first adhesive layer, the low-refractive index layer, and the second adhesive layer. In the following Examples and Comparative Examples, The same. The ratio of the thickness of the adhesive (adhesive layer) (total thickness of the first adhesive layer and the second adhesive layer) to the total thickness (overall thickness) in the adhesive sheet with a low refractive index layer The ratio is about 95%. Then, the separation member is peeled from the adhesive sheet containing the low refractive index layer, and the backlight LED side light type is laminated with the laminated body of the first adhesive layer, the low refractive index layer, and the second adhesive layer. The light guide plate of the liquid crystal display (light guide plate type LCD) is integrated with the reflection plate, and an optical sheet for the light guide plate type liquid crystal display of this embodiment is prepared. Table 1 shows the evaluation results of the brightness characteristics and the like of the optical sheet for the light guide plate type liquid crystal display.

[Example 2] A light guide plate and a reflection of a backlight LED edge-lit liquid crystal display (light guide plate type LCD) were reflected in the same manner as in Example 1 except that the low refractive index layer was formed by directly coating the reflection plate. An optical sheet for a light guide plate type liquid crystal display was obtained by integrating the plates. That is, the optical sheet for the light guide plate type liquid crystal display of this embodiment does not have an 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. Otherwise, it is the same as in Example 1. Table 1 shows the evaluation results of the brightness characteristics and the like of the optical sheet for the light guide plate type liquid crystal display.

[Example 3] The foregoing low-refractive index layer coating liquid was replaced with 3 g of the low-refractive index layer-forming coating liquid, and a mixed photobase generator (WPBG266 [Wako Pure Chemical Industries, Ltd.] trade name] was added: 1.5%. MIBK concentration solution) 0.18g, bis (trimethoxysilyl) ethane (TCI) (5% concentration MIBK solution) 0.05g liquid, and formed into a refractive index of 1.14 (void ratio: 61%), except for this Other than in the same manner as in Example 1, the light guide plate of the backlight LED edge-lit liquid crystal display (light guide plate type LCD) and the reflection plate were integrated to obtain an optical sheet for the light guide plate type liquid crystal display. Table 1 shows the evaluation results of the brightness characteristics and the like of the optical sheet for the light guide plate type liquid crystal display.

[Example 4] The light guide plate of the light guide plate type liquid crystal display optical sheet of Example 1 was further subjected to the first adhesive layer, the low-refractive index layer, and the second through the same method as in Example 1. The laminated body of the adhesive layer is bonded to the diffusion plate, and an optical sheet (reflection plate / light guide plate / diffusion plate integrated sheet) for the light guide plate type liquid crystal display of this embodiment is prepared. Table 1 shows the evaluation results of the brightness characteristics and the like of the optical sheet for the light guide plate type liquid crystal display.

[Example 5] An acrylic film with a thickness of 40 μm was used as the substrate film instead of the substrate film used in Example 1, and the substrate film was not peeled off, that is, the surface on the side opposite to the low refractive index layer of the substrate film. A 5 μm-thick adhesive with a separator (second adhesive layer) was attached to the light guide plate and a light guide plate of a backlight LED edge-lit liquid crystal display (light guide plate LCD) in the same manner as in Example 1 except that The reflecting plate is integrated to obtain 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, the aforementioned acrylic film (substrate film) having a thickness of 40 μm is present between the low refractive index layer and the second adhesive layer. Example 1 is the same. Table 1 shows the evaluation results of the brightness characteristics and the like of the optical sheet for the light guide plate type liquid crystal display.

[Comparative Example 1] A light guide plate and a reflective plate of a backlight LED edge-lit liquid crystal display (light guide plate type LCD) are integrated with a 12 μm thick adhesive without interposing a low-refractive index layer and a reflective plate. In the same manner as in Example 1, an optical sheet for a light guide plate type liquid crystal display was obtained. Table 1 shows the evaluation results of the brightness characteristics and the like of the optical sheet for the light guide plate type liquid crystal display.

[Comparative Example 2] As in Example 1, the light guide plate of the backlight LED edge-lit liquid crystal display (light guide plate type LCD) and the reflection plate were not integrated, and were laminated with air therebetween. That is, in this comparative example, no layer other than the air layer is disposed between the light guide plate and the reflection plate, and the low refractive index layer and the adhesive layer (adhesive) are not used. The evaluation results of the brightness characteristics at this time are shown in Table 1.

[Table 1]

In Table 1, the luminance characteristics (luminance uniformity) were measured in the following manner.

(Measurement method of brightness characteristics) For a television having an LED edge-light type backlight, a light guide plate and a cymbal were manufactured by using any one of the foregoing embodiments or comparative examples (however, the comparative example 2 An optical sheet for a light guide plate type liquid crystal display, which is laminated with an air layer and is not integrated), makes the television display a white display, and then uses a spectroradiometer SR-UL2 (TOPCON TECHNOHOUSE Co.'s product) (Name) Each brightness of each coordinate is measured from the incident side of the LED of the light guide plate toward the terminal side.

As shown in Table 1, when the light guide plate and the reflective plate are integrated using the optical sheet for the light guide plate method of Examples 1 to 5, light from the LED will propagate from the incident side of the light guide plate to the terminal side, and the brightness characteristics Good (even brightness). In addition, when the light guide plate and the reflecting plate are integrated, no foreign matter is mixed in, and the yield during the assembly step is also good.

On the other hand, in the comparative example, light leaks before the light propagates to the terminal side of the light guide plate, and a result is obtained that the light cannot penetrate to the terminal side. That is, Comparative Example 1 does not use a low-refractive index layer, but integrates the light guide plate and the reflective plate only with an adhesive (adhesive layer), and the brightness is lower than that of the example. In Comparative Example 2, the light guide plate and the reflective plate were not laminated, but were laminated with air therebetween. As a result, not only brightness unevenness (uniformity in brightness) occurred, but foreign matter was mixed in, and the yield during the assembly step was reduced.

In addition, in Example 5, the base film was assembled into an optical sheet for a light guide plate type liquid crystal display, but in other examples, the base film was not attached to an optical sheet for a light guide plate type liquid crystal display ( The substrate is peeled off, and the optical sheet for a light guide plate type liquid crystal display is reduced in thickness. Industrial availability

As described above, according to the present invention, it is possible 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.

10‧‧‧ Substrate

20‧‧‧ Low refractive index layer

20'‧‧‧ coated film (precursor layer)

20``‧‧‧ Liquid containing gel smash

30‧‧‧ Adhesive layer (adhesive)

40‧‧‧Optical film (first optical film or second optical film)

101‧‧‧feed out roller

102‧‧‧Coating roller

105‧‧‧ take-up roll

110‧‧‧Oven area

111‧‧‧hot air heater (heating mechanism)

120‧‧‧Chemical treatment zone

121‧‧‧ lamp (light irradiation mechanism) or hot air heater (heating mechanism)

201‧‧‧feed out roller

202‧‧‧Liquid storage area

203‧‧‧ doctor knife

204‧‧‧Micro-gravure

210‧‧‧ Oven area

211‧‧‧Heating mechanism

220‧‧‧Chemical treatment zone

221‧‧‧ lamp (light irradiation mechanism) or hot air heater (heating mechanism)

251‧‧‧ take-up roller

1000, 2000, 6000 ‧‧‧ light guide plate type liquid crystal display (light guide plate type LCD)

A1 ~ A6, A12, A123‧‧‧Unit

1010‧‧‧light guide (first or second optical film)

1020‧‧‧Reflector (first or second optical film)

1030‧‧‧ 稜鏡

1040‧‧‧ diffuser (with diffuser diaphragm)

1050‧‧‧brightening film

1060‧‧‧Lower polarizer

1070‧‧‧Adhesive (adhesive layer)

1080‧‧‧ LCD panel

1090‧‧‧ diffuser (first or second 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 configuration of the 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 according to the present invention. 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 a part of the steps of a method for manufacturing an optical sheet for a light guide plate type liquid crystal display of the present invention and an example of an apparatus used therefor. FIG. 5 is a diagram schematically showing some steps of a method for manufacturing an optical sheet for a light guide plate type liquid crystal display according to the present invention and another example of a device used in the method. 6 is a cross-sectional view showing an example of the configuration of a light guide plate type liquid crystal display without the optical sheet for a light guide plate type liquid crystal display of the present invention.

Claims (9)

An optical sheet for a light guide plate type liquid crystal display, wherein 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 low refractive index layer is 1.25 or less. For example, the optical sheet for a light guide plate type liquid crystal display according to claim 1, wherein the first optical film and the second optical film are a lower plate polarizing plate, a brightness enhancing film, a cymbal plate, a diffusion plate, a light guide plate, or a reflecting plate, respectively. The optical sheet for a light guide plate type liquid crystal display according to claim 1 or 2, wherein 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 at least one of the first optical film and the second optical film is an laminated layer with an adhesive layer and the low refractive index layer interposed therebetween. The optical sheet for a light guide plate type liquid crystal display according to claim 1 or 2, wherein the aforementioned low refractive index layer is a void layer having a porosity of 35% by volume or more. A backlight unit for a light guide plate type liquid crystal display includes the optical sheet for a light guide plate type liquid crystal display according to any one of claims 1 to 6, an edge light, and a light guide plate. The backlight unit for a light guide plate type liquid crystal display according to claim 7, wherein the aforementioned side light is an LED side light. A light guide plate type liquid crystal display includes a backlight unit for a light guide plate type liquid crystal display according to claim 7 or 8.