JP5462482B2 - Method for producing solid material containing layered inorganic compound, solid material and formed body formed using the same - Google Patents

Description

  The present invention relates to a method for producing a solid material containing a layered inorganic compound and having excellent heat resistance, gas barrier properties and transparency. Furthermore, the present invention relates to a molded body such as a sealing material, a packaging material, a protective material, a gas barrier layer forming material, a circuit board, and a display material, at least partly formed using such a solid material.

  The function of gas barrier is widely used in industry. For example, electronic materials such as displays, packaging materials for pharmaceutical-related products such as retort foods and drugs, and the like are required to have high gas barrier performance against oxygen and water vapor. These gas barrier functions are often achieved by using glass, aluminum foil, an inorganic thin film by vapor deposition, or the like. However, glass is generally very transparent but is not flexible and easily broken. Moreover, the weight is heavy and the difficulty of handling is a problem. Since aluminum foil is a metal, there is a problem that light does not transmit and the contents cannot be seen. Inorganic thin films and the like are vulnerable to external forces such as bending, and gas barrier performance is likely to deteriorate due to cracking.

  On the other hand, studies have been made to improve gas barrier properties by using layered inorganic compounds such as smectite group clay and clay minerals typified by mica. Layered inorganic compounds are suitably used for various applications in that they are inexpensive and have many species that are excellent in water dispersibility (see, for example, Non-Patent Document 1).

  The layered inorganic compound is composed of a plate-like inorganic crystal called a nanosheet as a unit structure. The size, shape, and composition of nanosheets vary depending on the type of layered inorganic compound, but typical clay minerals have a thickness of about 1 nm, and other layered inorganic compounds have a thickness of about 0.2 nm to several nm. Most of the things. On the other hand, the average length in the longitudinal direction of the nanosheet is generally 40 to 50 nm for smectite synthesized by the hydrothermal method, 200 to 400 nm for natural montmorillonite, and 0.1 for mica or hectorite synthesized by the melting method. 10 μm, a synthetic product of natural mica and hydrotalcite, especially large ones of several tens of μm, which varies depending on the production area and synthesis method.

  Many of the nanosheets have a permanent charge, and in order to compensate for the charge, inorganic ions are often present between the layers of the nanosheet to maintain electrical neutrality. Hereinafter, in this specification, ions that play a role of compensating the permanent charge of the nanosheet are referred to as interlayer ions, and unless otherwise specified, the interlayer ions are ions existing between the nanosheet layers in a solid state. Shall mean.

  Extensive research has been conducted on materials obtained by adding a small amount (generally about 5% by mass or less) of layered inorganic compounds such as clay minerals to the resin, and some of them have been put into practical use as gas barrier films formed into films. (For example, see Non-Patent Document 2).

  However, many of these conventional materials are used by modifying the surface of the nanosheet with a small average length of 40 to 50 nm in order to improve dispersibility in hydrophobic resins and organic solvents, The gap between the layers of nanosheets stacked (hereinafter referred to as interlayer distance) is widened, and the average length of the nanosheets in the longitudinal direction is small, so the gas movement path is not sufficiently long, resulting in gas permeation. Since the route is expanded, high gas barrier properties are hardly exhibited (see Patent Document 1). In addition, in order to suppress the expansion of the interlayer distance, when inorganic ions having a small size are used as interlayer ions, the layered inorganic compound is usually dispersed only in an aqueous solvent, so that the obtained material itself is hydrophilic. Therefore, even if a high gas barrier property is exhibited against dry gas, the barrier performance of water vapor is often inferior (see, for example, Non-Patent Document 3).

  In order to improve the gas barrier property by extending the gas movement path when the gas permeates, studies have been made on using layered inorganic compounds such as natural montmorillonite and synthetic mica having a large average length in the longitudinal direction of the nanosheet. However, when natural montmorillonite is used, yellowish brown coloration occurs. In addition, a layered inorganic compound having a large average length in the longitudinal direction of the nanosheet usually tends to cause cleavage and insufficient dispersion, and the remaining of a lump of particles and further light scattering due to disorder of the oriented laminated structure. As a result, it is difficult to obtain a transparent material having no light and high light transmittance and a film made of them. In particular, when the film thickness is increased to several microns or more in order to improve mechanical strength and gas barrier characteristics, the increase in haze due to coloring and scattering as described above becomes significant.

Conventionally, when a transparent material is obtained using a layered inorganic compound having a large average length in the longitudinal direction of a nanosheet, it has been necessary to perform a strong mechanical dispersion treatment for a long time. In addition, it is necessary to separate only nanosheets that are very slightly contained in the dispersion obtained by such mechanical dispersion and that have been sufficiently cleaved and dispersed by applying a very strong gravitational acceleration. For this reason, the utilization efficiency of material was bad and it was a manufacturing method which was difficult to use cost-effectively.
That is, conventional materials containing a layered inorganic compound often have a trade-off relationship between transparency and gas barrier performance, particularly water vapor barrier performance, and in particular, the layered inorganic compound having a large average length in the longitudinal direction of the nanosheet. It was difficult to achieve both transparency and gas barrier performance at a high level using a compound.

JP 2006-37079 A Edited by Sudo Kodankai, “Invitation to Clay Science: Clay's Face and Charm”, Sankyo Publishing, p. 6 (2000) Nakasumi, edited by “Development of Polymer Nanocomposites”, Frontier Publishing, p. 25-90 (2004) “Overview of Flexible Display”, eExpress, p. 223-224 (2005)

  An object of the present invention is to provide a method for producing a solid material containing a layered inorganic compound, which has transparency, a gas barrier property against oxygen and water vapor, and heat resistance, at a high raw material usage rate and with high efficiency. And

As a result of intensive studies in order to solve the above problems, the present inventors have completed the following invention. That is, the present invention comprises the following steps:
(1) a step of phase-separating at least a liquid crystal phase and a non-liquid crystal phase with a dispersion of a layered inorganic compound dispersed in a dispersion medium, which may contain impurities;
(2) separating the liquid crystal phase from the dispersion; and (3) drying the separated liquid crystal phase to obtain a solid material;
A method for producing a solid material containing a layered inorganic compound is provided.

In addition, the present invention provides the following steps before the above step (1):
(4) A method for producing a solid material further comprising the step of cleaving the layered inorganic compound by mechanical treatment and / or chemical treatment.

The present invention also includes the following steps:
(5) The layered inorganic compound in the dispersion liquid to be treated with respect to the dispersion liquid in the step (1) or the liquid dispersion phase separated in the step (2) or the liquid dispersion to be treated. A step of performing cation exchange for exchanging 50% or more of interlayer cations possessed by inorganic cation with inorganic cation other than sodium ion, and anion exchange for exchanging anion species in the dispersion to be treated with hydroxide ions A method for producing a solid material further comprising:

The present invention also includes the following steps:
(6) Provided is a method for producing a solid material, which further includes a step of replacing 65% by mass or more of water contained in the dispersion subjected to the above step (5) with an organic solvent.

The present invention also includes the following steps:
(7) Provided is a method for producing a solid material, further comprising a step of adding a hydrophobic additive to the dispersion liquid obtained through the step (6).

  Moreover, this invention provides the manufacturing method of the solid material whose average aspect-ratio of the layered inorganic compound which exists in the liquid crystal phase immediately after the said step (2) when measured by the dynamic scattering method is 200 or more. .

  Moreover, this invention provides the manufacturing method of the solid material containing the nanosheet which the said layered inorganic compound consists of the composition of the hectorite synthesized by the melting method.

  Moreover, this invention provides the manufacturing method of the solid material containing the nanosheet which the said layered inorganic compound consists of the composition of the synthetic mica synthesized by the melting method.

  Moreover, this invention provides the solid material manufactured by the said manufacturing method.

  Moreover, this invention provides the said solid material whose content rate of the said layered inorganic compound is 10 mass% or more.

  The present invention also provides a formed article comprising the solid material as at least one of the constituent elements and having a total light transmittance of 80% or more when measured at an optical path length of 3 μm according to JIS-K7361.

  According to the present invention, in the production of a solid material containing a layered inorganic compound, a layered inorganic compound having a large average length in the longitudinal direction of the nanosheet is used to improve gas barrier properties and the like, and the solid material has excellent transparency. Can be granted.

  The method for producing a solid material containing a layered inorganic compound according to the present invention comprises the following steps: (1) a dispersion of a layered inorganic compound dispersed in a dispersion medium, which may contain impurities, at least a liquid crystal phase and a non-liquid crystal phase. (2) separating the liquid crystal phase from the dispersion; and (3) drying the separated liquid crystal phase to obtain a solid material. The layered inorganic compound used in the present invention is one in which at least a part exhibits a liquid crystal transition phenomenon in the state of a colloid dispersed in a dispersion medium typified by water to form a liquid crystal phase, and is typically a single layer. Up to several tens of layers can be cleaved (peeled) in the dispersion medium. Layered inorganic compounds include layered transition metal oxygenates such as clay minerals, layered polysilicates, layered silicates, layered double hydroxides, layered phosphates, titanium / niobates, hexaniobates or molybdates , Layered manganese oxide, layered cobalt oxide, and the like. Of these, clay minerals, layered niobates and the like are preferable because they easily form a liquid crystal phase. Ease of availability, ease of synthesis, and ability to disperse the nanosheets constituting the layered inorganic compound into a single layer or a state in which several to several tens of layers are laminated to disperse water in a typical dispersion medium Is particularly preferred from clay minerals.

  The clay mineral may be natural clay or synthetic clay, and for example, mica, vermiculite, montmorillonite, beidellite, saponite, hectorite, stevensite, or magadiaite, hydrotalcite, caryonite, halloysite can also be used. However, in order to improve the transparency of the solid material according to the present invention, it is preferable to use synthetic clay, and synthetic saponite, synthetic hectorite, synthetic stevensite, synthetic mica, synthetic karionite, synthetic hydrotalcite and the like are preferable.

  In terms of ease of development of liquid crystal transition, the layered inorganic compound preferably has an average aspect ratio of 200 or more in the liquid crystal phase immediately after fractionation, as measured by a dynamic scattering method, for example, a smectite group. Hectorite or synthetic mica synthesized by the melting method or clay belonging to the above is preferable. Moreover, the clay mineral in which the edge part of a nanosheet becomes things other than hydroxyl groups, such as a fluorine, is preferable. Examples of such layered inorganic compounds include fluorinated hectorite synthesized by the melting method (for example, NHT Sol B2, manufactured by Topy Industries, Ltd.), and fluorinated mica synthesized by the melting method (for example, NTS-5, Topy). Kogyo Co., Ltd.), swellable mica obtained by heat-treating high-purity talc with sodium silicofluoride or lithium silicofluoride (for example, ME-100 or MEB-3, manufactured by Corp Chemical Co., Ltd.), etc. Can be mentioned. In particular, fluorinated hectorite synthesized by the melting method or fluorinated mica synthesized by the melting method is preferable from the viewpoint of easy separation of the liquid crystal phase and the non-liquid crystal phase and ease of delamination.

  The larger the average aspect ratio of the layered inorganic compound, the more generally gas barrier properties are generally achieved in the obtained solid material. However, in the present invention, the average aspect ratio measured in the liquid crystal phase is 200 or more. It is not essential, and is a representative value of the average aspect ratio at which the liquid crystal phase is easily developed in the above-described suitable layered inorganic compound (the layered inorganic compound in the liquid crystal phase is easily extracted).

  In addition, although the composition of these layered inorganic compounds (nanosheet and interlayer ion) is represented by a composition formula described in publicly known literatures, they show an ideal composition and are included in the present invention. The composition of the various layered inorganic compounds used need not exactly match the composition formula in the literature.

  The liquid crystal phase in the present invention is a group in which the orientation of the nanosheet in which the layered inorganic compound is dispersed is aligned to some extent in the dispersion medium by aligning the surface of the nanosheet by the liquid crystal transition of the layered inorganic compound in the dispersion. A phase that behaves as a collection of Since the layered inorganic compound generally has refractive index anisotropy in the in-plane direction and the thickness direction of the nanosheet, birefringence is expressed in a group of groups in which the surfaces of the nanosheet are aligned to some extent. For this reason, in the liquid crystal phase, various textures and interference colors characteristic of the liquid crystal are confirmed by observation with a polarizing microscope having a magnification of 100 times or less. On the other hand, in the non-liquid crystal phase in which the nanosheets are not aligned and each nanosheet is dispersed or aggregated in a discrete direction, the anisotropy of the refractive index is canceled and the whole is cancelled. As a result, the refractive index is also isotropic. Therefore, the determination of whether the dispersion is a liquid crystal phase or a non-liquid crystal phase can be made based on whether various textures and interference colors characteristic of the liquid crystal are confirmed by observation with a polarizing microscope with a magnification of 100 times or less. .

  Here, the average particle diameter X of the layered inorganic compound used in the present invention and the aforementioned average aspect ratio Z will be described.

  The average aspect ratio Z is a layered inorganic when the average particle diameter obtained by measuring a dispersion obtained by dispersing the layered inorganic compound used in the present invention in a desired dispersion medium by a dynamic light scattering method is X. The unit thickness d of the nanosheet of the compound is defined as being represented by the relationship of Z = X / d.

  The unit thickness d is a powder containing only the layered inorganic compound or a dispersion containing only the layered inorganic compound as a solid content on a base material (for example, a smooth resin substrate or a silicon wafer) that can sufficiently eliminate the influence of the base material upon measurement. Is a value obtained by a known measurement method such as an X-ray diffraction method with respect to the thin film obtained after being sufficiently dried, and if it is a smectite group or mica group clay, usually 0. It is known to be about 93 nm to 1.04 nm. In certain types of clays (montmorillonite, hectorite, stevensite) that have been dehydrated by exchanging interlayer ions from sodium ions to lithium ions, the nanosheets seem to be close to the theoretical limit. However, since the unit thickness d obtained by the measurement method at that time is 0.95 nm, in such a layered inorganic compound, the unit thickness d of the nanosheet may be considered to be 0.95 nm.

  The above-mentioned average particle diameter X obtained by the dynamic light scattering method will be described. Measurement of the average particle size of layered inorganic compounds in a dispersion medium is very difficult to define and measure because the shape is plate-like particles. It is considered that the average particle size and the particle size distribution data calculated by a conventional particle size distribution calculation algorithm using the dynamic light scattering method after sufficiently considering the influence of the distance are relatively highly valid.

  However, if the concentration of the dispersion is too high or the particle density in the dispersion is too high, the macroscopic properties of the dispersion will increase the viscosity or thixotropic behavior compared to the dispersion medium. In this case, the average particle diameter calculated by the dynamic light scattering method is likely to be estimated larger than the actual size of the plate-like particles in the longitudinal direction.

  Similarly, particles must be present in close proximity in the dispersion liquid, and dynamic light is applied to the dispersion liquid whose concentration is close to or closer to the wavelength region of the light used for measurement. In the measurement by the scattering method, two or more particles close to each other may be recognized as one large particle, and as a result, the average particle diameter may be greatly estimated.

  Therefore, in order to obtain a highly valid average particle size by dynamic light scattering measurement, measurement is performed with multiple concentrations of dispersion, including the lowest possible concentration, for each concentration of dispersion. It is considered that one of the preferable methods is to perform measurement in a state where the obtained average particle diameter value hardly depends on the concentration. Therefore, the average particle diameter X in the present specification is a measurement result at a concentration twice as high as the measurement result at a certain concentration corresponding to the above state (preferably an average measured three times or more) (similarly 3 It is assumed that the difference is preferably within ± 20%, preferably within ± 10%, more preferably within ± 5%.

  It is difficult to uniquely determine the concentration of the preferred dispersion when performing such a measurement because it varies depending on the type of layered inorganic compound, the state of dispersion, the sensitivity of the device, etc., but the measuring device can measure with sufficient accuracy. On the premise that it is a concentration range, the solid content concentration of the dispersion containing only the layered inorganic compound as the solid content is preferably in the range of 0.001% by mass or more and 1.0% by mass or less, and the more preferable range is 0.01 mass% or more and 0.7 mass% or less, and the most preferable range is 0.02 mass% or more and 0.5 mass% or less. It should be noted that since the scattering intensity generally increases as the aspect ratio increases, it is generally necessary to measure with a dispersion having a lower concentration.

  With such meticulous care, a reasonable average particle diameter X and average aspect ratio Z can be obtained. The average aspect ratio Z uses the average particle diameter X as defined in this specification. Therefore, it is not necessarily a true value corresponding to the actual dispersion state of the layered inorganic compound in the dispersion.

  In the present invention, a layered inorganic compound that causes liquid crystal transition is dispersed in a dispersion medium, or a dispersion prepared in advance as a dispersion is used to separate them into a liquid crystal phase and a non-liquid crystal phase. Is separated from the dispersion. The dispersion medium in which the layered inorganic compound is dispersed is typically water alone or water as a main component, but may be an organic solvent as a main component. The liquid crystal phase has a higher density than the non-liquid crystal phase and exists in the liquid crystal phase because it exists as a collection of groups in which the orientation of the dispersed nanosheets is aligned to some extent in the dispersion medium. The compound has a larger average aspect ratio than the layered inorganic compound present in the following non-liquid crystal phase. On the other hand, the non-liquid crystal phase is not aligned in the direction of the dispersed nanosheets, and it is considered that each nanosheet is oriented in a disjoint direction, and the density is lower than the liquid crystal phase and exists in the non-liquid crystal phase. The average aspect ratio of the layered inorganic compound is relatively small. Therefore, if the layered inorganic compound present in the liquid crystal phase is selectively extracted in a state of being separated into a liquid crystal phase and a non-liquid crystal phase, a layered inorganic compound having a large average aspect ratio and excellent alignment characteristics can be selected. Can be obtained. As a result, a solid material having excellent transparency can be obtained in spite of using a layered inorganic compound having a larger average length in the longitudinal direction (that is, a larger average particle diameter).

  Although not bound by theory, nanosheets in the liquid crystal phase are easy to align with a certain amount of plane in the dispersion medium, so even when removing the dispersion medium to obtain a solid material, the nanosheets face each other. As a result, it is considered that the orientation of the material is highly facilitated, and as a result, the generation of internal defects due to orientation failure is suppressed, and the transparency of the material is improved. Furthermore, since nanosheets in the liquid crystal phase have relatively large average aspect ratios, it is considered that physical properties such as gas barrier properties, mechanical strength, and heat resistance are improved based on the knowledge of known layered inorganic compounds.

  Since the liquid crystal phase has a higher density than the non-liquid crystal phase, the liquid crystal phase is often obtained by being separated into lower layers in the direction of gravitational acceleration. Therefore, it can be phase-separated into a liquid crystal phase and a non-liquid crystal phase by standing in an environment where gravity is applied. The time required for separation varies depending on the type, concentration, average aspect ratio, viscosity, and the like of the layered inorganic compound, but in some cases it can be sufficiently separated, and when it is allowed to stand for several days, it generally separates satisfactorily.

  When a known cleavage (fine dispersion) treatment described later is performed, the separation between the liquid crystal phase and the non-liquid crystal phase is improved. Moreover, the speed | rate which isolate | separates a dispersion into a liquid crystal phase and a non-liquid crystal phase can be raised using the well-known separation method using a density difference, such as a centrifugation method. The volume separation ratio of each of the liquid crystal phase and the non-liquid crystal phase varies greatly depending on various factors. However, in the present invention, it is possible to separate into a liquid crystal phase and a non-liquid crystal phase even if very little, and a layered inorganic compound in the liquid crystal phase can be selectively extracted. Good.

  When the concentration of the dispersion is high, the dispersion may not be separated into a liquid crystal phase and a non-liquid crystal phase, and the whole may be a liquid crystal phase. In this case, if the conditions can be separated into a liquid crystal phase and a non-liquid crystal phase, the aspect ratio is small and the nanosheet component to be transferred to the non-liquid crystal phase is mixed in the liquid crystal phase, so the average aspect ratio is relatively large, In addition, a layered inorganic compound having excellent orientation characteristics cannot be selectively obtained.

  In such a case, it is preferable to reduce the solid content concentration of the dispersion by, for example, further adding water to the dispersion. A preferable solid content concentration for separating the dispersion into a liquid crystal phase and a non-liquid crystal phase varies depending on the type, concentration, average aspect ratio, viscosity, and the like of the layered inorganic compound, but generally more than 1.5 mass% and 6 mass. %, Preferably more than 1.5 mass% and less than 5 mass%, more preferably more than 2 mass% and less than 4.5 mass%. However, even if it is outside the above range, this is not limited to the case where the separability is improved by applying a large gravitational acceleration by a centrifugal method or the like. It can be separated into a non-liquid crystal phase.

  In order to improve the transparency of the solid material according to the present invention and to change the colloidal state dispersed in a dispersion medium typified by water into a liquid crystal transition state, the nanosheet constituting the layered inorganic compound is as close to a single layer as possible. It is preferable to provide a step of separating to cleaved and forming a dispersed state. For this purpose, known fine dispersion devices such as shaking devices, ultrasonic dispersion, bead mills, ball mills, roll mills, homomixers, ultra mixers, disper mixers, penetrating high pressure dispersion devices, collision type high pressure dispersion devices, porous high pressure dispersion devices Promoting peeling and cleaving through mechanical treatment that applies mechanical force with a device, debris type high pressure dispersion device, (collision + penetration) type high pressure dispersion device, ultra high pressure homogenizer, etc., promotes dispersion of layered inorganic compounds It is preferable in the sense that the nanosheet as a unit layer is cleaved to approach a dispersed state.

  Among these, as a fine dispersion device, ultrasonic dispersion, homomixer, ultramixer, dispermixer, penetration type high pressure dispersion device, collision type high pressure dispersion device, porous type high pressure dispersion device, deduction type high pressure dispersion device, (collision + penetration) It is more preferable to use a high-pressure disperser and an ultrahigh-pressure homogenizer.

Examples of the high-pressure dispersing device include an ultra-high pressure homogenizer (trade name: Microfluidizer) manufactured by Microfluidics Corporation or a nanomizer manufactured by Nanomizer. Can be mentioned. A preferable pressure includes a dispersion treatment under a high pressure, particularly 100 kgf / cm ² or more. When the pressure is increased, the layered inorganic compound is crushed and refined, and the average aspect ratio is reduced. As a result, the gas barrier property of the solid material may be reduced. When the solid material is formed into a film, the film formation characteristics and mechanical strength are reduced. In some cases, it may be preferable to perform dispersion treatment under a pressure of 100 kgf / cm ² or less.

  In contrast, the layered inorganic compound, which is difficult to cleave and disperse because the average aspect ratio is too large, can be dispersed at high pressure by utilizing the feature that the layered inorganic compound is crushed and refined by dispersing under high pressure or ultrasonic waves. By carrying out treatment or ultrasonic treatment, it may be dispersed while being crushed to an average aspect ratio that is easy to disperse and does not cause a significant decrease in physical properties such as gas barrier properties.

  In particular, hectorite and synthetic mica synthesized by the melting method, and synthetic mica modified from talc have a large average aspect ratio, and therefore, the above-mentioned fine processing by crushing may be performed in order to promote further cleavage. Often preferred. However, too much refinement treatment increases the viscosity of the dispersion mainly due to the increase in the number of particles, and as a result, it may be difficult to separate the liquid crystal phase from the non-liquid crystal phase. is there. Such a phenomenon tends to occur particularly in a mica-based layered inorganic compound having a large amount of permanent charge in the nanosheet.

  In order to cleave the layered inorganic compound, a chemical treatment may be used in place of or in combination with the above mechanical treatment. As the chemical treatment, for example, a dispersant represented by a known anionic system such as sodium polyacrylate having a relatively low molecular weight or polyacrylic acid is used in an extremely small amount, specifically 0.5 mass relative to the layered inorganic compound. A method of advancing dispersion by adding it to the dispersion at a level of less than about%, preferably about 0.15% by mass, is suitable for the present invention. However, if too much of these dispersants are added, after removing the solvent, they intercalate between the layers of the layered inorganic compound, increasing the interlayer distance and reducing the gas barrier property of the solid material or reducing the heat resistance. Therefore, attention is necessary.

  The liquid crystal transition in the dispersion and the accompanying phase separation phenomenon between the liquid crystal phase and the non-liquid crystal phase appear at a certain solid content concentration above a certain level. However, if the average aspect ratio is reduced by the above-mentioned fine processing, the liquid crystal transition occurs. The minimum solid content concentration of the dispersion for expression may increase. As a result, the dispersion liquid did not separate into a liquid crystal phase and a non-liquid crystal phase before crushing, but the whole liquid crystal phase was separated into a liquid crystal phase and a non-liquid crystal phase at the same solid content concentration. It becomes possible to separate into a liquid crystal phase and a non-liquid crystal phase at a low dilution ratio (that is, without reducing the solid content concentration so much).

  In the present invention, the dispersion may contain impurities. In this case, the liquid crystal phase may be separated from the non-liquid crystal phase and the impurities that may be contained. Impurities are impurities that settle in the dispersion, typically contained in the layered inorganic compound or dispersion thereof at the time of acquisition, and are removed by a technique that applies a large gravitational acceleration, such as a centrifugal separation method. Is preferred. In particular, hectorite and mica synthesized by the melting method contain glassy components, and mica obtained by modifying natural talc contains a small amount of impurities derived from natural products. This gives good results in improving transparency and developing liquid crystal transition. In addition, gelation of excess impurity ions (ions contained other than interlayer ions) in the dispersion, especially the card house structure, etc., is promoted by techniques using ion exchange resins and ion exchange membranes described later. The anions (particularly fluorine ions and sulfate ions that are likely to be contained) that are a major factor in forming the associated structure to be removed may be removed before separation into a liquid crystal phase and a non-liquid crystal phase.

  The above-described impurity removal operation such as centrifugation and ion exchange may be performed before or after the separation of the dispersion into a liquid crystal phase and a non-liquid crystal phase. However, it is generally preferable that the operation of removing impurities by applying a large gravitational acceleration is performed before the dispersion is separated into a liquid crystal phase and a non-liquid crystal phase. In general, if the impurities are settled and removed by applying a large gravitational acceleration by a centrifugal separation method or the like, the dispersion can be easily separated into a liquid crystal phase and a non-liquid crystal phase, so that impurity removal and phase separation can be promoted simultaneously. Therefore, it is convenient.

  In addition, the above-described micronization treatment and the addition of a dispersant may be performed before the dispersion is separated into a liquid crystal phase and a non-liquid crystal phase, or may be performed after the separation. When the separation between the liquid crystal phase and the non-liquid crystal phase is improved (when it is easy to separate even at the same concentration), it is preferable to perform the separation before the separation. However, it is necessary to fully consider the influence of a decrease in physical properties such as gas barrier properties due to the reduction of the average aspect ratio due to the miniaturization treatment.

  In the present invention, exchangeable ions present in the dispersion may be exchanged for desired inorganic ions, and a solid material containing a layered inorganic compound obtained from the dispersion may be produced. The exchangeable ions present in the dispersion include, in addition to exchangeable interlayer ions that compensate for the charge of the nanosheet, other ions contained in the layered inorganic compound in the form of impurities and surplus ions. is there. In particular, it is preferable to exchange or remove ions having a charge opposite to that of interlayer ions with desired ions.

  In the production method of the present invention, when a layered inorganic compound having a negative nanosheet permanent charge is used, at least 50% or more of the exchangeable interlayer ions (cations) are inorganic ions other than sodium ions, particularly lithium ions and potassium ions. , Barium ion, cesium ion, lead ion, calcium ion, magnesium ion, ammonium ion, hydrogen ion and preferably at least one selected from metal ions having an atomic number of 19 or more, and exchange with lithium ion or ammonium ion It is particularly preferred to do this. In addition, there exists a cation as a surplus ion that can be regarded as one of the impurities that exists beyond the amount to compensate for the charge of the nanosheet (in fact, such a surplus ion and the interlayer ion necessary for charge compensation of the nanosheet are dispersed. It is preferable to exchange with the above cations.

If there is a cation as the surplus ion, the charge is guaranteed, and the anion also exists as a surplus ion that can be regarded as one of the impurities. The main ones are sulfate ion, hydroxide ion, fluorine ion, chlorine ion and the like. In particular, sulfates having sulfate ions (SO ₄ ²⁻ ) are also included in natural clay minerals and synthesized clay minerals. Especially, synthetic smectites synthesized by hydrothermal method include sodium sulfate and magnesium sulfate. In many cases, 0.05 to 4% by mass of sulfate is contained in terms of sodium sulfate. Moreover, in the layered inorganic compound in which the hydroxyl group of the octahedral layer of the nanosheet is fluorinated, the fluorine raw material used in the synthesis often remains as fluorine ions. In the present invention, it is preferable to exchange or remove the anions as the surplus ions to the desired ions as much as possible.

  Excess anions are preferably exchanged for monovalent anions, but most preferred are exchange for hydroxide ions. In this case, it is preferable to replace the surplus cation with ammonium ion or hydrogen ion. In that case, surplus ammonium ions or hydrogen ions generated by the above exchange react with surplus hydroxide ions to produce water, which is actually surplus from the dispersion mainly composed of water. Ions will be removed.

  When the cations in the dispersion are exchanged with hydrogen ions, usually, the ions corresponding to the interlayer ions are also exchanged with hydrogen ions. In this case, if the interlayer ions are kept as hydrogen ions, the liquidity is acidic. When the interlayer ion is a hydrogen ion, this state is sufficient, but by adding an alkali cation in this state, the interlayer ion can be exchanged for a desired ion other than the hydrogen ion.

  For example, when it is desired to use potassium ions as interlayer ions, potassium hydroxide (KOH) is added as neutral ions by adding potassium hydroxide (KOH) until the liquidity becomes neutral while the interlayer ions are hydrogen ions. The hydrogen ions that have been added and the added hydroxide ions cause a neutralization reaction to become water, and the remaining potassium ions are replaced with interlayer ions, whereby the interlayer ions can be converted to potassium ions. Similarly, lithium hydroxide (LiOH) may be added in the case where lithium ions are used as interlayer ions, and ammonia water may be added in the same manner as described above so that the dispersion is neutral.

When the interlayer ions are exchanged for hydrogen ions, depending on the type of layered inorganic compound, the layered inorganic compound may be decomposed by hydrogen ions and replaced with other ions generated by the decomposition of the interlayer ions. This reaction is likely to occur with small synthetic saponite and synthetic hectorite. In this case, in order to suppress decomposition by hydrogen ions, it is necessary to devise such as exchanging with hydrogen ions and performing the neutralization reaction while cooling. Further, after the above neutralization reaction, the ionic species generated by decomposition of the layered inorganic compound by hydrogen ions may be removed by further exchanging the ionic species to the target ionic species.
By exchanging or removing surplus ions that can be regarded as one of the aforementioned impurities as much as possible as described above, the effect of the present invention is greatly enhanced. Specifically, by the ion exchange or removal described above, cleavage of the layered inorganic compound proceeds, aggregation is suppressed, the viscosity of the dispersion decreases, and the layered inorganic compound is not only contained in the water-containing solvent but also in the organic solvent. Effects such as high dispersion can be obtained. In particular, it does not cause aggregation or gelation in an organic solvent (especially an organic solvent having a low water content) without modifying (modifying) part of the layered inorganic compound with an organic cation or silane treatment. The effect of dispersing in is obtained. Therefore, addition of water-insoluble resin, etc. that cannot be easily mixed uniformly by precipitation, etc., if there is moisture, without treatment such as the above modification that can reduce heat resistance such as conventional organic treatment As a result, it is a solid material that has a low moisture absorption rate and excellent water resistance, and is provided with heat resistance and dimensional stability derived from a layered inorganic compound, gas barrier properties, particularly water vapor barrier properties, etc. Can be obtained. Further, since such a solid material is formed via a highly dispersed dispersion (removing the dispersion medium) as described above, light scattering by the aggregated particles is suppressed, and the above-described effects are achieved. It becomes possible to combine transparency.

  The total ratio of preferred sulfate ions and fluorine ions after removal of surplus ions is preferably 0.001 k% by mass or less, more preferably 0.001% by mass or less when the ratio of the layered inorganic compound in the solid material is k% by mass. It is 0008 k% by mass or less, particularly preferably 0.0005 k% by mass or less, and most preferably 0.0003 k% by mass or less. Among them, the ratio of sulfate ions is particularly preferably 0.0001 k% by mass or less, and most preferably 0.00005 k% by mass or less.

  As a method for performing ion exchange, a method using a known ion exchange resin, ion exchange membrane, or semipermeable membrane is suitable. Either order of exchange of the cation and the anion may be first, but from the viewpoint of suppressing the aggregation of the particles, it is often better to exchange the cation after exchanging the anion first.

  When ion exchange is performed, the viscosity of the dispersion to be treated for ion exchange may be any concentration as long as the dispersion flows. However, when the solid content concentration of the dispersion is too high, viscosity may increase and ion exchange efficiency may decrease, or the dispersion may not pass through a column packed with an ion exchange resin. In some cases, the ion exchange efficiency is improved by reducing the solid content concentration of the dispersion to such an extent that the liquid crystallinity in the dispersion disappears. However, if the solid content concentration of the dispersion liquid is too low, the amount of removal of the dispersion medium when removing the dispersion medium increases and it takes time to remove, and when removing by drying etc., a large amount of energy is required for drying. You may need it.

  Therefore, a preferable range of the solid content concentration of the dispersion liquid to be treated at the time of ion exchange is generally 0.05% by mass or more and 20% by mass or less, and more preferably 0.1% by mass or more and 15% by mass or less. In the range of 0.2% by mass or more and 12% by mass or less, more preferably in the range of 0.3% by mass or more and 10% by mass or less, and most preferably 0.4% by mass. The range is 8% by mass or less.

  The ion exchange in the present invention can be carried out typically at a temperature higher than the freezing point of the dispersion medium used and lower than the boiling point.

  It should be noted that the dispersion before separating the liquid crystal phase and the non-liquid crystal phase, the separated liquid crystal phase, or the liquid crystal phase within the range that does not hinder ion exchange and separation between the liquid crystal phase and the non-liquid crystal phase. Polymers, polymer precursors, compatibilizers can be obtained by diluting the liquid phase or at least part of the dispersion medium (typically water) contained in the liquid crystal phase or diluting liquid with an organic solvent. Agents, dispersants, surfactants, stabilizers, heat stabilizers, antioxidants, weathering agents, UV absorbers, crosslinking agents, chemical modifiers, lubricants, crystal nucleating agents, colorants, birefringence control agents, etc. One or more kinds of products may be added. The additive may be added as a solid, may be added in a melted state by heating or the like, or may be added in a solution state dissolved or dispersed in an arbitrary solvent. When the additive is hydrophobic, the dispersion medium (typically 65% by mass or more of the dispersion medium) in the separated liquid crystal phase or in the diluted liquid is replaced with an organic solvent, and then the above-mentioned additive is hydrophobic. It is preferable to add an additive. For example, after fractionation of the liquid crystal phase, cation exchange and anion exchange after dilution or without dilution, solvent replacement with an organic solvent, and addition of a hydrophobic additive can be performed in this order. The hydrophobic additive means an additive that cannot be dissolved or dispersed in water at the addition temperature and concentration among the above-described additives. Hereinafter, in the present specification, a dispersion in which at least the layered inorganic compound contained in the separated liquid crystal phase is dispersed, typically the above-described diluent, the dispersion obtained by the above substitution with an organic solvent, and the liquid crystal phase directly. Alternatively, the dispersion obtained by adding the above-mentioned additives together with the dilution and / or substitution is also collectively referred to as “liquid crystal phase-derived dispersion”. The liquid crystal phase-derived dispersion may be in a liquid crystal state or a non-liquid crystal state.

  Moreover, instead of converting the interlayer ions into inorganic ions as described above, ion exchange may be performed by known methods to organic cations such as ammonium salts, phosphonium salts, and imidazolium salts. Moreover, you may silane-treat the edge part of a nanosheet mainly with a silane coupling agent. However, in this case, since the surface of the layered inorganic compound is organically modified with an organic substance as described above, there is a concern that the gas barrier property and heat resistance may be lowered.

  When exchanging exchangeable interlayer ions by the method as described above, the exchange rate to a desired inorganic ion is preferably 50% or more, more preferably 85% or more, still more preferably 90% or more, and still more preferably It is desired to be 95% or more, particularly preferably 97% or more, and as close as possible to 100%.

  In the present invention, the dispersion medium in the dispersion when separating into a liquid crystal phase and a non-liquid crystal phase and performing ion exchange as necessary contains at least water, and usually preferably contains water or water as a main component. The reason for this is that water can be cited as a solvent that easily causes liquid crystal transition, that it is easy to prepare a dispersion in which a water-swellable layered inorganic compound is highly dispersed, and the ion exchange rate to inorganic ions is high. There are few problems of elution from an ion exchange resin, an ion exchange membrane or a semipermeable membrane.

  A layered inorganic compound contained in the dispersion is obtained by further mixing a polymer, a polymer precursor, other optional additives, and the like with this dispersion as necessary, and then removing the dispersion medium by heating and drying. It is possible to obtain a solid material that makes use of the features of a large average aspect ratio and high transparency. Such a material in the present invention has preferable characteristics such as high gas barrier properties of oxygen and water vapor, good dimensional stability, and high heat resistance even in a high water vapor concentration environment.

  In the present invention, the separated liquid crystal phase is dried directly or by removing the dispersion medium after making the liquid crystal phase-derived dispersion liquid, thereby forming a solid material containing a layered inorganic compound present in the liquid crystal phase. it can. In the production method of the present invention, in particular, after the liquid crystal phase or the liquid crystal phase-derived dispersion liquid is set in a stationary state such as a liquid film, the nanosheet layer can be highly oriented and laminated by removing the dispersion medium. Is possible. As a method for confirming the oriented laminated state, analysis of an X-ray diffraction spectrum by an X-ray diffractometer and direct observation of the laminated state by TEM are effective. Conventionally, various studies and evaluations have been conducted by X-ray diffraction measurement, such as the orientation lamination state of a film formed on a support such as a glass substrate, and the dispersion and peeling state of nanosheets in a nanocomposite containing clay. In general, the intensity and position of the main peak (bottom reflection peak on the lowest 2θ side) generated in the X-ray diffraction spectrum by the first-order diffraction of the 001 plane of the layered inorganic compound, and the X-ray diffraction spectrum in the low 2θ region By raising the background or the like, it is possible to know the lamination state (average interval of layers) and the dispersion state of the nanosheets.

  In the solid material according to the present invention, particularly when the content ratio of the layered inorganic compound is 10% by mass or more and 100% by mass or less, it is obtained by spreading the dispersion to form a liquid film and then removing the dispersion medium, and the nanosheet The average interlaminar distance in the film-like material with well-aligned orientation was measured in an environment in the range of 20 to 28 ° C. and 25 to 80% relative humidity, preferably 25 ° C. and 50% relative humidity. The value converted from the 2θ position of the primary diffraction peak of the 001 plane in the X-ray diffraction spectrum is preferably 10 nm or less, more preferably 7 nm or less, still more preferably 4 nm or less, and most preferably 2 nm or less. Further, suitable gas barrier properties are developed at 1.8 nm or less, and even higher gas barrier performance is developed at 1.6 nm or less.

  When the above average average interlayer distance is converted into the top position (value of 2θ) of the first-order diffraction peak described above, a single layer of nanosheets is used when a wavelength of 1.54Å which is a general Kα ray of copper is used. In a film made of smectite group clay or synthetic mica group clay having a thickness of about 1 nm, 2θ usually corresponds to a region of 0.8 to 9.5.

  Note that whether or not the average interlayer distance of the nanosheets in the film is in the above preferable range can also be confirmed by directly measuring the interlayer distance by observation with a TEM.

  In the production method of the present invention, in addition to the layered inorganic compound, additives such as a polymer, a polymer precursor, and optional additives may be further mixed as necessary, but the inclusion of the layered inorganic compound in the solid material The ratio is preferably 1% by mass or more, more preferably 3% by mass or more, further preferably 5% by mass or more, further preferably 7% by mass or more, and more preferably 10% by mass or more. It is very preferable because the characteristics derived from the layered inorganic compound are strongly expressed. In particular, in order to dramatically improve the gas barrier properties, the content ratio of the layered inorganic compound in the solid material is preferably 10% by mass or more, more preferably 30% by mass or more, and further preferably 50% by mass. It is above, More preferably, it is 70 mass% or more. On the other hand, the content ratio of the layered inorganic compound may be more than 95% by mass and 100% by mass or less, but in that case, flexibility and mechanical strength may be reduced and cracks may occur, and gas may leak from there. Therefore, when the content ratio of the layered inorganic compound is more than 95% by mass and 100% by mass or less, it is desirable to use a device having a particularly large average aspect ratio effective for improving the strength.

  In the present invention, separation of the liquid crystal phase and the non-liquid crystal phase in the colloidal state is typically performed with water or a dispersion mainly composed of water, and exchange of interlayer ions and surplus ions with desired ions is performed. In some cases, it is usually carried out using a dispersion mainly composed of water. Therefore, the main component of the dispersion medium of the dispersion obtained through the above process is water, and in a solid material obtained by removing the dispersion medium after adding some additive to the dispersion, water resistance and high water vapor concentration Gas barrier properties in the environment may be reduced.

  In the above case, by any method such as heating, light irradiation, etc., the chemistry such as addition reaction, condensation reaction, polymerization reaction, etc. in the added additive, within the molecule, between the molecules, or between the additive and the layered inorganic compound. The reaction may be performed to generate a new chemical bond, thereby improving the water resistance of the solid material and the gas barrier property in a high water vapor concentration environment. However, since it is generally difficult to completely hydrophobize an additive that is inherently water-soluble by the above-mentioned treatment, the additive is hydrophobic from the viewpoint of water resistance and gas barrier properties in a high water vapor concentration environment. It is more preferable to use those having low solubility in water.

  In order to use an additive that is hydrophobic and has low solubility in water, it is desirable to mix the additive after converting the dispersion medium (especially water) in the dispersion into one mainly composed of an organic solvent. For example, the liquid crystal phase after separation of the liquid crystal phase and the non-liquid crystal phase (after ion exchange when ion exchange is performed) or a diluted liquid thereof has high affinity with water, specifically, high compatibility with water. A method of mixing an organic solvent can be used.

  Examples of the organic solvent highly compatible with water include organic solvents having high polarity, such as methanol, ethanol, 2-methoxyethanol, 2-ethoxyethanol, 2-isopropoxyethanol, 2- (methoxyethoxy). Ethanol, 2-butoxyethanol, 1-propanol, 2-propanol, 2-butanol, t-butanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 2-methoxyethyl acetate, diacetone alcohol, free Alcohol, ethyl acetoacetate, tetrahydrofurfuryl alcohol, ethylene glycol, diethylene glycol, dipropylene glycol, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, diethylene glycol Monoethyl ether, dipropylene glycol monoethyl ether, triethylene glycol, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, acetone, acetonyl acetone, acetonitrile, ethylene carbonate, propylene carbonate, acetic acid, formamide, N-methylformamide, N, N-dimethyl Formamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, N, N, N, N-tetramethylurea, 2-pyrrolidone, N-methylpyrrolidone, methyl carbamate, γ-butyllactone, triacetin, isopropyl formate, Triethylamine, tetrahydrofuran, 1,2-dimethoxyethane, 1,4-dioxane, dimethyl sulfoxide, trimethyl phosphate, triethyl phosphate, lithium A tributyl acid etc. can be mentioned. Among these, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone and the like are suitable solvents.

  One kind of the organic solvent may be used, or a plurality of different kinds may be mixed. When mixing a plurality of different types of organic solvents, the organic solvent may be added sequentially to the dispersion mainly composed of water, or the organic solvent mixed in advance at a predetermined ratio may be added, Both methods may be used in combination. Further, an organic solvent may be added while stirring the separated liquid crystal phase or a diluted solution thereof or performing the fine dispersion treatment described above.

  In particular, a method of sequentially adding an organic solvent to the dispersion, for example, polar activators represented by low molecular weight alcohols such as methanol, and osmotic swelling such as formamide and N-methylformamide having a large number of donors and acceptors. A method of adding another solvent after adding a solvent or the like having a large action may be useful because it can exhibit an action of maintaining and improving the dispersibility of the layered inorganic compound or suppressing aggregation.

  When mixing the organic solvent as described above, in order to obtain a dispersion mainly composed of the organic solvent, the amount of water in the dispersion is reduced in advance to increase the solid content concentration of the dispersion. You may keep it. Examples of such a method include a method of evaporating water by heating the dispersion under normal pressure or reduced pressure.

  In the present invention, the most preferable method for forming a solid material in which an additive having hydrophobicity and low solubility in water and a layered inorganic compound having liquid crystal transition properties is fused is a dispersion in a liquid crystal phase state. After diluting as necessary to eliminate the liquid crystal transition state, the above-described ion exchange is performed, and after mixing with a desired organic solvent, the ratio of water in the dispersion is reduced to form a dispersion medium in the dispersion. This is a method of increasing the proportion of the organic solvent occupied. By this method, most of the water can be removed from the dispersion medium to make most of the dispersion medium an organic solvent, and high dispersibility can be exhibited even in such a state. As such a method, for example, there is a method of evaporating water by heating the dispersion under normal pressure or reduced pressure. To reduce the proportion of water in the dispersion after mixing with an organic solvent, It is preferable that the added organic solvent has a boiling point higher than that of water.

  In addition, the amount of water in the dispersion medium may be reduced using a water adsorbent such as molecular sieve, silica gel, activated alumina, zeolite, soda lime, magnesium sulfate, and certain ion exchange resins. Alternatively, water may be removed by a hydrolysis reaction using a silane compound such as tetraethoxysilane or tetramethoxysilane, magnesium ethylate, or the like. Further, a plurality of methods as described above may be used in combination. For example, after removing most of the water by heating under reduced pressure, the water may be further removed by molecular sieves.

  In the present invention, the dispersion medium may be removed from the dispersion containing both water and the organic solvent at the same time, for example, by heating and drying. However, the dispersion medium containing water and the organic solvent having different boiling points and vapor pressures may be simultaneously used. When removing and obtaining a solid material, the uniformity of the mixed state of a layered inorganic compound and an additive tends to become low. On the other hand, for example, by heating with stirring in a sufficiently reduced pressure, most of the water can be removed, and a dispersion in which the layered inorganic compound is substantially dispersed in the organic solvent can be obtained. In this case, the residual ratio of water in the dispersion medium can be preferably 35% by mass or less (that is, 65% by mass or more of the dispersion medium is replaced with an organic solvent), more preferably 20% by mass or less, and still more preferably The amount can be 15% by mass or less, more preferably 10% by mass or less, and particularly preferably 7% by mass or less. Thus, by reducing the residual ratio of water in the dispersion medium, even when using an additive such as a hydrophobic resin that cannot be dissolved and precipitates when water is present, the additive and the layered inorganic It becomes possible to prepare a dispersion liquid in which the compound is uniformly mixed and dispersed, and as a result, various physical properties such as hydrophobicity of the solid material can be greatly improved.

  Furthermore, depending on the type of layered inorganic compound, the type of interlayer ions to be exchanged, and the type of organic solvent to be dispersed, the dispersibility of the layered inorganic compound is further improved by sufficiently removing water as described above. Specifically, the transparency of the dispersion may be improved, or an increase in viscosity, which may be caused by an increase in the number of particles accompanying the progress of cleavage of the layered inorganic compound, may be observed.

  In the present invention, many of the layered inorganic compounds in a liquid crystal phase state in an aqueous dispersion may form a dispersion form in a non-liquid crystal state in the organic solvent by the dispersion treatment in the organic solvent as described above. is there. In that case, the transparency of the dispersion is further improved and the viscosity often increases. And since the dispersion state in the non-liquid crystal state in such an organic solvent corresponds to the nanosheet being uniformly dispersed in the dispersion liquid, even when an additive such as a hydrophobic resin is introduced. These and the nanosheet are uniformly mixed and dispersed. As a result, it is possible to obtain a solid material in which the additive and the nanosheet are uniformly dispersed even in the solid material when the dispersion medium is removed from the dispersion. This effect can greatly improve the gas barrier property, transparency, heat resistance, and the like of the solid material according to the present invention. Since the above effect greatly varies depending on the residual amount of surplus ions of the layered inorganic compound, generally, a better dispersion state can be obtained in the organic solvent by sufficiently removing surplus ions.

  Furthermore, an organic solvent having higher hydrophobicity, that is, less compatible with water, may be added to the liquid crystal phase-derived dispersion obtained by the above-described method using an organic solvent as a main dispersion medium. Examples of such organic solvents include aromatic hydrocarbons (benzene, toluene, ethylbenzene, xylene, etc.), ethers (ethyl ether, diethyl ether, dibutyl ether, diphenyl ether, etc.), ketones (dimethyl ketone, diethyl ketone, methyl isobutyl). Ketone, methyl ethyl ketone, methyl isobutyl ketone, etc.), aliphatic hydrocarbons (n-pentane, n-hexane, n-octane, cyclohexane, etc.), halogenated hydrocarbons (chlorobenzene, carbon tetrachloride, methylene chloride, chloroform, dichloromethane) 1,2-dichloroethane, perchloroethylene, etc.), nitriles (propionitrile, butyronitrile, benzonitrile, etc.), esters (ethyl formate, butyl formate, ethyl acetate, methyl acetate, propyl acetate, isoacetic acid Chill, ethyl butyrate, butyl butyrate, methyl propionate, methyl methacrylate, dioctyl phthalate, methyl salicylate, etc.), acetophenone, benzophenone, methyl cellosolve, benzyl alcohol, and silicone oil. As a result, the types of additives that can be added to the dispersion can be further expanded, and the physical properties and functions of the formed body after removal of the dispersion medium can be further enhanced.

  The polymer as an additive directly or with dilution and / or solvent substitution or the like for the dispersion or fractionated liquid crystal phase obtained before separating into a liquid crystal phase and a non-liquid crystal phase, or When a polymer precursor additive is added, such a polymer or polymer precursor is dissolved or finely dispersed in water, a mixed solvent of water and an organic solvent, and an organic solvent according to the type of the dispersion medium. Any known polymer or polymer precursor as shown below can be used as long as it is dispersed. Preferably, it is highly hydrophobic. Further, a solid material may be formed by mixing one or more kinds of polymers or polymer precursor additives heated and melted with the dispersion obtained as described above. .

  For example, polyvinyl alcohol resin and derivatives thereof, modified polyvinyl alcohol resin, polyvinyl acetal resin, polyvinyl butyral resin, ethylene-vinyl alcohol copolymer, epsilon caprolactam, dextrin, oxidized starch, starch such as etherified starch, carboxymethyl cellulose, Cellulosic resins such as hydroxyethyl cellulose and triacetyl cellulose, cellulose fiber, gelatin, agar, flour, gluten, polyacrylic acid, sodium polyacrylate, polyethylene glycol, polyacrylamide, polyethylene oxide, protein, deoxyribonucleic acid, ribonuclein Acid, polyamino acid, polyphenol, benzoic acid compound, polyurethane resin, fluororesin, alkyd resin, meta Ryl resin, epoxy resin, phenol resin, polyester resin, aromatic polyester resin, aliphatic polyester resin, polyamide resin, polyimide resin, transparent polyimide resin, styrene resin, acrylic resin, aromatic polycarbonate resin, Aliphatic polycarbonate resin, aliphatic polyolefin resin, cyclic olefin resin, polyacetal resin, polysulfone resin, polyethersulfone resin, amorphous fluorine resin, polyphenylene ether resin, urea resin, allyl resin, silicon resin, Thermosetting and thermoplastic resins such as silicone resin, benzoxazine resin, phenol resin, unsaturated polyester resin, bismaleimide triazine resin, alkyd resin, furan resin, melamine resin, polyurethane resin, aniline resin Or it can be used a photocurable resin.

  Examples of the photocurable resin include an epoxy resin containing a latent photocationic polymerization initiator and a silicone resin. In addition, when hardening the said photocurable resin, you may apply heat simultaneously with light irradiation.

  In the present invention, a curing agent, a curing catalyst or the like may be used in combination with the thermosetting resin and the photocurable resin, but they are generally used for curing the thermosetting resin and the photocurable resin. If it is a thing, it will not specifically limit. Specific examples of the curing agent include polyfunctional amines, polyamides, acid anhydrides, and phenol resins, and specific examples of the curing catalyst include imidazole. These curing agents and curing catalysts can be used alone or in combination. Further, an aqueous dispersion material such as latex or emulsion may be used.

  Among the aforementioned resins, polyethersulfone (polyethersulfone) -based resins are preferable from the viewpoint of heat resistance. Since hardly soluble resins such as polyethersulfone are likely to precipitate when water is present in the dispersion, it is necessary to mix with a dispersion using an organic solvent from which water has been sufficiently removed. From the viewpoint of gas barrier properties, polyvinyl alcohol resins and ethylene-vinyl alcohol copolymers (Eval), or resins having a curing reactivity with heat or light such as epoxy resins are also suitable. From the viewpoints of optical properties, water resistance and water vapor gas barrier properties, cyclic olefin resins are also suitable. Furthermore, the resin mentioned above may be used independently and may use 2 or more types together. In order to improve the transparency of the solid material according to the present invention, the above polymer or polymer precursor is also preferably transparent or less colored. Further, when the solid material is required to have heat resistance, for example, a high coloring temperature, the polymer or polymer precursor preferably has such heat resistance.

  Examples of the dispersant include amide compounds such as lauric acid amide and ethylenebisstearic acid amide, amine compounds such as polylaurylamine, polyvinylamine, and stearylamine, ethylene-vinyl acetate copolymer resins, acid-modified resins, and amide resins. Examples thereof include polar resins and aminosilanes.

  Antioxidants that suppress oxidative degradation during heating include, for example, hindered phenols, hindered amines, phosphorus-based or sulfur-based antioxidants, etc., and flame retardants that make it difficult to burn are inorganic flame retardants such as antimony trioxide. Can be mentioned.

  Examples of the chemical modifier include, as an organic reactive group, a vinyl group, an epoxy group, a styryl group, a methacryloxy group, an acryloxy group, an amino group, a ureido group, a chloropropyl group, a mercapto group, a sulfide group, an isocyanate group, and the like. Silane coupling agents, in particular organoalkoxysilanes, can be mentioned, especially in view of cross-linking with polymers or precursors thereof, which have an epoxy group, amino group or vinyl group, for example vinyltrimethoxysilane, 3-glycol. Sidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane N-phenyl-3-a Roh trimethoxysilane can be preferably exemplified.

  The birefringence control agent is a molecule that adjusts the birefringence of the formed body, and includes, for example, a molecule containing a rigid mesogen group in the molecule, such as fluorene, naphthalene, carbazole, biphenyl, 4-biphenylcarboxylic acid, 4- Hydroxybiphenyl, 2-hydroxybiphenyl, diphenyl ether, benzophenone, stilbene, diphenylacetone, 1,4-diphenyl-1,3-butadiene, benzaldehyde azine, 4-benzoylbiphenyl, chalcone, 1,3-diphenoxybenzene, phenanthrene, tolan Etc.

  The various additives described above may be used alone or in combination of two or more. In addition, the additive can be present in the material after removal of the dispersion medium as it is or changed into some form by chemical reaction, etc., by heating or light irradiation, etc. at the time of removal of the dispersion medium or after formation of the formed body. It may be removed from the formed body.

  The timing of mixing the additive with the dispersion may be arbitrary, and after the additive is mixed with the dispersion, another solvent (for example, an organic solvent) as described above may be added, or the dispersion may be separated from the dispersion. After adding the solvent, the additives may be mixed with the dispersion, or another organic solvent is added to the dispersion containing water to remove most of the water, and then the additives are mixed. May be. The additive may be added as a solid, may be added in a melted state by heating, or may be added in a solution state dissolved or finely dispersed in an arbitrary solvent.

  Furthermore, it is preferable to perform a stirring or the above-mentioned fine dispersion treatment at the time of mixing or after mixing the above-mentioned additives to obtain a dispersion in which the layered inorganic compound and the above-mentioned additives are more uniformly mixed.

  In addition, in the case where a gas component is mixed in the dispersion liquid by performing such stirring or the fine dispersion treatment described above, the gas component is obtained by a process such as vacuum defoaming, ultrasonic irradiation, or centrifugation. Is preferably degassed. These treatments may be carried out after stirring or the fine dispersion treatment described above, or may be carried out simultaneously during these treatments. In particular, when forming a gas barrier material or optical material, bubbles and voids derived from mixed gas components are generated, which causes a reduction in gas barrier properties and transparency. It is very important to do.

  A desired solid material can be produced by drying the liquid crystal phase produced through the above-described process directly or by removing the dispersion medium after making the liquid crystal phase-derived dispersion liquid. The solid content concentration of the liquid crystal phase or the liquid crystal phase-derived dispersion produced through the above process is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and 1.0% by mass or more. More preferably, 5.0% by mass or more is more preferable, and 10% by mass or more is very preferable because the drying time is further shortened or the drying temperature can be lowered. The solid content concentration of the liquid crystal phase or the liquid crystal phase-derived dispersion is not limited as long as mixing, defoaming, and the like are possible, and may be a paste with a very high viscosity. As the method for removing the dispersion medium, centrifugation, filtration, vacuum drying, freeze vacuum drying, standing in an inert gas atmosphere, and heat evaporation are preferable. Alternatively, a plurality of these methods may be combined.

  In the case of the heating evaporation method, specific examples of removing the dispersion medium include, for example, a temperature of 30 ° C. to 250 ° C., preferably 40 ° C. to 200 ° C., more preferably 50 ° C. to 150 ° C. in a forced air oven. A method for obtaining a desired material by drying under conditions of 10 seconds to 24 hours, preferably 1 minute to 10 hours, more preferably 3 minutes to 5 hours, and even more preferably 5 minutes to 3 hours. Can be mentioned. However, the optimum drying time varies depending on the shape of the material, the solid content concentration of the liquid crystal phase or liquid crystal phase-derived dispersion, the solvent used, the liquid amount of the liquid crystal phase or liquid crystal phase-derived dispersion, and the like.

  When the above-mentioned additives are added, any reaction such as heating, light irradiation, electron beam irradiation, etc. can be performed within the additive molecule, between the additive molecules, and between the additive and the layered inorganic compound. The water resistance of the formed body and the gas barrier property against water vapor may be improved by causing a chemical reaction such as a polymerization reaction to generate a new chemical bond. They may be performed before the dispersion medium is removed, may be performed in parallel when the dispersion medium is removed, or may be performed after the dispersion medium is removed.

  When there is no strong convection phenomenon due to heat, boiling of the dispersion medium, or mechanical stirring during the removal of the dispersion medium, the nanosheets tend to be regularly aligned in the resulting formed body due to the plate shape of the nanosheet. In particular, in a film-like solid material formed by allowing the dispersion to stand and dry on a planar support, the nanosheet of the layered inorganic compound is as parallel as possible to the support surface, that is, the film surface. In general, a structure in which the nanosheets are stacked so as to be stacked can be formed. Such a film is based on a known production method of a film containing a layered inorganic compound using a dispersion liquid in which the layered inorganic compound is dispersed (for example, JP-A Nos. 2003-276124 and 2007-63118). Can be produced.

  For example, when forming a film-shaped formed body using the solid material according to the present invention, in addition to the advantages of high transparency, high gas barrier properties, and high heat resistance, dimensional stability is good and storage at high temperatures. Effects such as a small decrease in elastic modulus can be obtained.

  The dimensional stability against temperature change can be evaluated by the linear expansion coefficient. The linear expansion coefficient of the film which is an example of the formed body according to the present invention is an average from 50 ° C. to at least about 160 ° C., preferably from 50 ° C. to about 200 ° C., more preferably from 50 ° C. to about 260 ° C. The absolute value of the linear expansion coefficient is preferably 30 ppm or less, more preferably 20 ppm or less, further preferably 10 ppm or less, further preferably 7 ppm or less, further preferably 5 ppm or less, and most preferably 3 ppm or less. Is also possible.

  In addition, the above-mentioned support used at the time of drying may be a flat surface or a curved surface, and the material is not particularly limited. Further, such a film-like material may be used while being fixed on the above-described support, or may be used after being peeled off from the support.

  When used while being fixed (attached) on the support, an anchor coat layer may be provided on the surface of the support in order to make it difficult to peel the film from the support. As the anchor coat agent used for forming the anchor coat layer, known ones can be used without any particular limitation. Examples thereof include anchor coating agents such as isocyanate, polyurethane, polyester, polyether, polyethyleneimine, polybutadiene, polyolefin, and alkyl titanate. Known suitable anchors described in, for example, Japanese Patent No. 3984791 A coating agent can be appropriately selected and used. Alternatively, a good result may be obtained by subjecting the surface of the support to corona treatment, flame plasma treatment, ozone treatment, electron beam treatment, or the like.

  When the film is peeled off from the support and used, the surface of the support may be easily peeled off. As the easy peeling process, for example, ultraviolet irradiation process, electron beam irradiation process, ion beam irradiation process, corona discharge process, plasma process (for example, remote plasma process, flame plasma process), physical process (for example, contact area is reduced) Machine processing for processing the surface). Also, by applying a resin that reduces adhesiveness such as silicone resin, softness or Young's modulus is changed by receiving physical stimuli such as light and heat, or peelability is imparted by foaming. An easy release layer may be provided by applying an agent or the like. A plurality of these processes may be combined.

  In addition, in order to peel the formed body based on this invention from a support body and to utilize as a self-supporting film | membrane, it is necessary to have a certain level or more mechanical strength. For this purpose, a film thickness of a certain level or more is required for handling. The film thickness is generally preferably 5 μm or more, more preferably 10 μm or more, still more preferably 20 μm or more, and particularly preferably 40 μm or more. Although there are not many factors that define the upper limit of the film thickness, it is preferably 20000 μm or less, more preferably 1000 μm or less, and even more preferably 500 μm or less from the viewpoint of transparency and cost.

  When the formed body according to the present invention is used as a film adhered on a support, there is no element that defines the film thickness. However, when the function as a gas barrier layer is expressed, the film has good gas barrier properties. Furthermore, it is preferably 0.1 μm or more, more preferably 0.3 μm or more, further preferably 0.5 μm or more, further preferably 0.8 μm or more, and 1 μm or more. Is particularly preferable, and most preferably 2 μm or more. However, if it is too thick, the film may be warped due to the generation of stress or the interface may be peeled off. Therefore, the film thickness is preferably 500 μm or less, more preferably 100 μm or less, More preferably, it is less than 50 micrometers, More preferably, it is less than 10 micrometers.

  In addition, since the film-like formed body according to the present invention can be formed by applying the dispersion liquid as described above, it has a high coverage with respect to unevenness and foreign matter on the support, and several thousand to several hundred thousand sheets of nanosheets are laminated. Because of its structure, pinhole defects do not occur in principle, so the gas barrier film with a uniform performance over a large area is more stable than a gas barrier film made by depositing an inorganic thin film on a conventional resin film by vapor deposition. It has the effect that it can form.

  The use of the synthesized layered inorganic compound as the layered inorganic compound is preferable in that the transparency of the resulting formed body can be improved. In the present invention, being transparent means that the total light transmittance is 80% or more even when the optical path length of light passing through the material is more than 3 μm, preferably even when the optical path length is more than 20 μm. Satisfying at least one of the characteristics that the total light transmittance is 80% or more, or that the transmittance of linear light at a wavelength of 400 nm is 70% or more even when the optical path length exceeds 3 μm. Means what

  The total light transmittance is preferably 85% or more, more preferably 88% or more, and most preferably 90% or more when the optical path length exceeds 20 μm. Further, the transmittance of linear light at the wavelength of 400 nm is preferably 75% or more, more preferably 80% or more, and most preferably 85% or more when the optical path length exceeds 3 μm.

  If the layered inorganic compound is not colored or the degree of coloring is slight, a material without coloring can be obtained, which is also preferable from the viewpoint of improving transparency. In the present invention, an uncolored material means a light transmittance of a material in a wavelength range of 380 nm to 780 nm measured with an ultraviolet-visible spectrophotometer even when the optical path length of light passing through the material is more than 3 μm. Is 10% or more in the entire wavelength region, and the difference between the maximum value and the minimum value of the light transmittance is within 30%, preferably within 25%, more preferably within 20%, still more preferably within 15%, most preferably Those within 10% are shown.

  Furthermore, a smaller haze (cloudiness) value is a more transparent material, which is generally preferred in many cases. Since the haze is caused by two factors, the internal structure of the material and the unevenness of the material surface, when the material is processed and formed into an arbitrary shape, the formation process has a great influence. Generally preferred haze is not more than 15%, more preferably not more than 10%, even more preferably not more than 5%, even more preferably even when the optical path length of light passing through the material is more than 3 μm. Is 3% or less, and particularly 1% or less can be said to be very good transparency. However, for applications that require light to be transmitted and diffused, a higher haze may be better.

  In the formed body according to the present invention, in which at least one of the components is formed using the solid material according to the present invention, typically, when the optical path length of the light passing through the solid material is more than 3 μm The total light transmittance is 80% or more. Or, typically, the transmittance of linear light at a wavelength of 400 nm when the optical path length of light passing through the solid material exceeds 3 μm is 70% or more. The formed body can be, for example, a composite made of the solid material according to the present invention and another material, and examples of the composite include a multilayer film.

  In the present invention, when the interlayer cation of the layered inorganic compound is exchanged with a desired inorganic ion other than sodium ion, the alkali metal, particularly sodium is hardly contained, or the alkali metal is strongly fixed between the nanosheet layers. Materials that are difficult to move are obtained. Such a material is an electronic device that dislikes alkali metals, such as a liquid crystal display, an organic EL display, a substrate of electronic paper, especially when used in the form of a film such as a film or sheet, or in the form of a seal at a joint, etc. It is considered suitable for applications such as sealing films and optical films.

  The solid material according to the present invention can simultaneously satisfy a plurality of required physical properties required for display applications such as high heat resistance, low linear expansion, high gas barrier, high transparency, and flexibility by selecting the kind and ratio of additives. Therefore, for example, an active matrix driving circuit serving as a backplane can be directly formed on a film-like solid material at a high temperature. The above process eliminates the need to use a conventional method such as forming a drive circuit on a heat-resistant support such as a glass substrate and then transferring it to a resin film, thereby reducing the number of display manufacturing steps. In addition to being suitable as a next-generation flexible display material, it is advantageous in terms of weight and cost.

  The above drive circuit may be constituted by a conventional silicon-based semiconductor technology, but an organic semiconductor or an amorphous inorganic semiconductor typified by pentacene or thiophenes may be used. In that case, a photolithography method may be used for circuit formation, or a printing method such as an inkjet method or a nanoimprint method may be used. Note that transparency is generally unnecessary if it is in a direction opposite to the backplane of the organic EL display or electronic paper, that is, the direction from which light is extracted. It is preferable to use it as a base material, particularly a gas barrier film, on the side of the front plane.

  Examples of liquid crystal display systems to which the solid material according to the present invention can be applied include TN, STN, VA, and IPS types. By using a birefringence control agent, birefringence in the film thickness direction can be freely set. Since it can be adjusted, it is not particularly limited. By adjusting the birefringence by the thickness and the birefringence control agent, it is also possible to apply to the retardation plate. Further, the organic EL display can be applied to both a top emission type and a bottom emission type. Furthermore, as electronic paper, for example, an electrophoretic drive system, an electronic powder fluid system, a system using liquid crystal, and the like can be used without any particular limitation.

  The circuit for driving the display can be used for both a passive matrix system and an active matrix system. As a usage form, it can be used as a substrate for forming a circuit or as a gas barrier layer for blocking oxygen and water vapor from the outside.

  In addition, the film made of the solid material of the present invention can be widely used as a flexible substrate of an electric circuit by taking advantage of the insulating property. Even when used as a substrate for an electric circuit, image processing is often used for alignment when mounting electronic components, and in that case, transparency is required. Is preferred. In particular, in a flexible printed circuit board in which a conductive portion on a substrate is formed by applying or printing a conductive ink, the conductive ink can be baked at a higher temperature by taking advantage of the heat resistance of the film and a low linear expansion coefficient. The resistivity of the conductor portion formed by coating or printing can be further reduced. Suitable applications of such flexible substrates and flexible printed substrates include RFID tag substrates and copper clad laminates.

  Furthermore, a material having a high total light transmittance can be applied to a device that needs to pass light, such as a solar cell. Since a high gas barrier performance is also required for a substrate, a protective layer, a sealing layer, and a back sheet for a solar cell, a material obtained by processing the solid material of the present invention into a film is suitable for a solar cell application. Furthermore, it is also promising as a protective film for protecting information recording sites of electronic recording media such as CD-R and DVD from oxygen and water vapor.

  When applying the film or film made of the solid material according to the present invention to the display, flexible substrate, flexible printed substrate, solar cell, electronic device having an organic semiconductor or amorphous inorganic semiconductor, etc. May be applied as it is, or if necessary, a formed body having another function (for example, a gas barrier film made mainly of an inorganic material, a reinforcing material made of a resin material, a protective layer for preventing scratches, a smooth surface, etc. Or the like) may be used. In particular, in order to further improve the gas barrier performance, it is effective to laminate a known inorganic thin film and a film or film made of the solid material of the present invention and a film mainly made of a resin material for protecting them.

  For example, on the solid material of the present invention formed in the form of a film on an arbitrary resin film, a film or a material made of a resin or an inorganic material, for example, may be laminated. You may laminate. Further, such a multi-layered film may be peeled off from the resin film. For example, a combination of resin film-anchor coat layer- {film-like solid material of the present invention-film made of resin or inorganic material-} smoothing layer-protective layer is preferable, and the film shown in parentheses above. The laminated part of the film made of a solid material and a resin or an inorganic material is not layered one by one, but may be laminated in any combination, such as a film made of a resin or an inorganic material, an anchor coat layer, a smoothing layer, The protective layer may or may not be present, and each may be a single layer or a plurality of layers.

When laminating films made of inorganic materials, the inorganic materials are known as gas barrier materials such as silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon oxide carbide, aluminum oxide, aluminum nitride, and mixtures thereof. Any thin film layer is suitable.
Further, a laminate comprising a gas barrier layer containing a layered inorganic compound having water swellability (hygroscopicity) as disclosed in Japanese Patent Application Laid-Open No. 2007-63118 and a film made of the solid material of the present invention as described above. Further laminating inside is suitable for developing a high gas barrier property against oxygen and water vapor even when water vapor is present, as disclosed in Japanese Patent Application Laid-Open No. 2007-22075. A gas barrier film comprising a gas barrier layer containing a layered inorganic compound having water swellability (hygroscopicity) and the film-like solid material of the present invention is transparent and retains high gas barrier properties even in an environment with a lot of water vapor. It is possible to absorb the moisture generated from the organic EL element or the like as disclosed in JP 2007-42616, for example, as disclosed in JP 2007-42616. Particularly suitable for organic EL elements that require gas barrier properties, particularly top emission type organic EL elements that cannot use colored desiccants, and completely solid organic EL elements that are difficult to put in a desiccant. is there. However, in this case, the above-described gas barrier layer is mounted on the organic EL element after the contained moisture is sufficiently removed by heating or the like.

  When mounting the gas barrier film having the solid material of the present invention as one of the constituent elements, including when mounting the sealing film of the organic EL element, on the substrate or the like, from the peripheral end where the bonding surface is present. Gas ingress is often a problem. Conventionally, invasion of oxygen and water vapor from the bonded portion at the peripheral edge has been suppressed by, for example, sufficiently removing the “gap” on the bonding surface and reducing the thickness of the adhesive necessary for bonding as much as possible.

  On the other hand, when the dispersion liquid used in the present invention is filled and coated so as to cover the end portion (the intrusion portion of oxygen or water vapor), the solid material according to the present invention can be formed into a curved surface. Due to a certain point and a gas barrier property, it is possible to form a seal at the end portion that suppresses intrusion of oxygen and water vapor. In particular, a gas barrier seal containing a layered inorganic compound having water swellability (hygroscopicity) and a gas barrier seal excellent in water vapor barrier properties are laminated at the end in the same manner as the organic EL element sealing mode described above. Thus, it is possible to efficiently prevent oxygen and water vapor from entering from the peripheral edge.

The gas permeation amount of the solid material as described above in the present invention is preferably less than 0.1 cc · mm / (m ² · day · atm) in the case of typical oxygen gas, more preferably 0.01 cc. Less than mm / (m ² · day · atm), more preferably less than 0.001 cc · mm / (m ² · day · atm), more preferably 0.0001 cc · mm / (m ² · day). · atm) is less than, more preferably less than ^{0.00001cc · mm / (m 2 ·} day · atm), very preferable when less than ^{0.000001cc · mm / (m 2 ·} day · atm) . The above gas permeation amount is preferably the same in an environment containing a lot of water vapor as well as dry oxygen gas. In particular, the above permeation amount is preferable even in an environment where the relative humidity is 90% at 40 ° C.

Similarly, the permeation amount of saturated water vapor is a permeability coefficient converted to 1 mm thickness of saturated water vapor at 40 ° C. and 90% relative humidity at 1 atm, and is preferably less than 0.1 g / (m ² · day). More preferably, it is less than 0.01 g / (m ² · day), more preferably less than 0.001 g / (m ² · day), and further preferably less than 0.0001 g / (m ² · day). There, more preferably less than ^{0.00001g / (m 2 · day)} , very preferable when less than ^{0.000001g / (m 2 · day)} .

  Hereinafter, the present invention will be described more specifically with reference to examples. The physical properties of the formed bodies in the following examples and comparative examples were evaluated by the following methods.

(1) Transparency of material Under conditions where the optical path length of light passing through the material exceeds 3 μm, the total light transmittance and haze were measured to estimate the transparency. The total light transmittance and haze were measured with a turbidimeter “NDH2000” manufactured by Nippon Denshoku Industries Co., Ltd. The total light transmittance and haze referred to here are the total light transmittance test method JIS K 7361, the plastic optical test method JIS K 7105, and the plastic transparent material defined in Japanese Industrial Standards. How to determine haze The haze is determined in accordance with JIS K 7136, and the total light transmittance is measured by “Measurement Method 1 in NDH2000” in which JIS K 7361 is obtained with respect to the total light transmittance and JIS K 7105 is obtained with respect to the haze. It is a thing.

(2) Average particle diameter The average particle diameter of the dispersed phase in the dispersion was determined by a dynamic light scattering method. As an apparatus, a zeta potential / particle size measurement system ELSZ-2 manufactured by Otsuka Electronics Co., Ltd. was used, and the concentration of the dispersion was changed at a liquid temperature of 25 ° C. (diluted with water). The pinhole diameter was 50 μm and ND In a state where the value is 100%, a concentration in which the average scattering intensity is in the range of 10,000 to 15000 cps is selected, measurement is performed three times at the concentration, and the average value of the average particle diameter based on the cumulant analysis result is determined in the dispersion. The average particle size of the dispersed phase was determined. In addition, the same measurement (range in which the average scattering intensity is 20000 to 35000 cps) is carried out even at a concentration twice the above measurement concentration, and the difference in the average particle diameter values obtained in the measurement of the two concentration dispersions is It was confirmed that it was within ± 5%.

(3) XRD spectrum measurement An analysis by X-ray diffraction was performed and measured by an X-ray diffractometer “RINT-2500” manufactured by Rigaku Corporation. The X-ray wavelength used is 1.54056 mm of Cu / Kα. The measurement environment was a temperature of 25 ° C. and a relative humidity of 50%.

[Example 1]
As the layered inorganic compound, a dispersion of synthetic hectorite (trade name: NHT Sol B2, manufactured by Topy Industries, Ltd.) synthesized by a melting method in which interlayer ions are mainly sodium ions was used.

  Using an ultrasonic homogenizer US-600T (manufactured by Nippon Seiki Seisakusho Co., Ltd.), 400 g of an NHT sol B2 aqueous dispersion having a solid content of 4.6% by mass is ultrasonicated for 30 minutes with a tip diameter of 36 mmφ and V-LEVEL of about 3. After irradiation, centrifugal separation was performed using a centrifuge hima CR20 (manufactured by Hitachi, Ltd.) and using a rotor number 13 and a 500 ml centrifuge tube at 8000 rpm for 10 minutes. The components of the upper dispersion other than a small amount of solids (mainly impurities) precipitated in the lower part are transferred to another container and allowed to stand for about 1 day. An aqueous dispersion in which the non-liquid crystal phase was separated was obtained.

  Using a dropper, only the aqueous dispersion in the lower liquid crystal phase state was carefully sucked out and extracted into a separate container so that the upper non-liquid crystal phase and the precipitated solid component were not mixed as much as possible. Similarly, the upper non-liquid crystal phase was also extracted into a separate container. The obtained liquid crystal phase had a solid content concentration of about 5.5% by mass, and the non-liquid crystal phase had a solid content concentration of about 3.0% by mass. The average particle size of the liquid crystal phase was 249 nm (255 nm when measured at twice the concentration), and that of the non-liquid crystal phase was 135 nm (132 nm when measured at twice the concentration).

  The aqueous dispersion in the liquid crystal phase obtained as described above is spread on a glass substrate having a thickness of 1.1 mm, dried on a hot plate at 60 ° C., and the layered inorganic compound is almost 100%. A thin-film solid material having a thickness of 16 μm was obtained.

  The total light transmittance of the thin film measured with a glass substrate was 83.0%, and haze was 7.8%. The total light transmittance of the glass substrate was 91.9% and the haze was 0.15%, indicating that the thin film has high light transmittance.

  When the X-ray diffraction spectrum was measured, the top of a very clear peak derived from the 001 plane was observed at a position of 2θ = 6.80 (1.30 nm in terms of interlayer distance). When the half width (FWHM) of this peak was measured, 2θ was 0.43 (0.082 nm distribution width in terms of interlayer distance), indicating that the layers of the layered inorganic compound nanosheets were densely stacked. It was done.

[Comparative Example 1]
The aqueous dispersion in the non-liquid crystal phase obtained in Example 1 is spread on the same glass substrate as in Example 1 and similarly dried at 60 ° C. on a hot plate, so that the layered inorganic compound is almost 100%. A film-like solid material having a thickness of 15 μm was obtained.

  When the film was measured together with the glass substrate, the total light transmittance was 69.9% and the haze was 51.2%, indicating that the film had low transparency.

  When an X-ray diffraction spectrum was measured, a clear peak top derived from the 001 plane was observed at a position 2θ = 6.89 (1.28 nm in terms of interlayer distance). When the half-value width of this peak was measured, it was 0.61 at 2θ (distribution width of 0.114 nm in terms of interlayer distance), and the variation in the alignment laminated structure was larger than in Example 1. It was suggested.

[Comparative Example 2]
The NHT sol B2 aqueous dispersion having a solid content concentration of 4.6% by mass used in Example 1 was spread on a glass substrate as it was, and similarly dried at 60 ° C. on a hot plate, so that the layered inorganic compound was almost 100%. %, A film-like solid material having a thickness of 16 μm was obtained.

  The total light transmittance measured with the glass substrate was 56.8%, and the haze was 79.1%, indicating that the transparency of the film was low.

  When an X-ray diffraction spectrum was measured, a clear peak top derived from the 001 plane was observed at a position 2θ = 6.89 (1.28 nm in terms of interlayer distance). When the half-value width of this peak was measured, it was 1.14 at 2θ (distribution width of 0.233 nm in terms of interlayer distance), and the variation in the alignment laminated structure was larger than in Example 1. It was suggested.

Claims (8)

The following steps:
(1) A dispersion of a layered inorganic compound dispersed in a dispersion medium, which may contain impurities and has a solid content concentration of more than 1.5% by mass and less than 6% by mass , is allowed to stand in a gravitational environment or gravity acceleration. the by to引加 step of phase separation into at least a liquid crystal phase and a non-liquid crystal phase;
(2) separating the liquid crystal phase from the dispersion; and (3) drying the separated liquid crystal phase to obtain a solid material;
A method for producing a solid material containing a layered inorganic compound. Prior to step (1) the following steps:
(4) The method for producing a solid material according to claim 1, further comprising a step of cleaving the layered inorganic compound by mechanical treatment and / or chemical treatment. The following steps:
(5) The layered inorganic compound in the dispersion to be treated with respect to the dispersion to be treated which is the dispersion in step (1) or the liquid crystal phase fractionated in step (2) or the diluted liquid of the liquid crystal phase. A step of performing cation exchange for exchanging 50% or more of interlayer cations possessed by inorganic cation with inorganic cation other than sodium ion, and anion exchange for exchanging anion species in the dispersion to be treated with hydroxide ions The method for producing a solid material according to claim 1, further comprising: The following steps:
(6) The method for producing a solid material according to claim 3, further comprising the step of replacing 65% by mass or more of water contained in the dispersion liquid obtained through the step (5) with an organic solvent. The following steps:
(7) The manufacturing method of the solid material of Claim 4 which further includes the step of adding a hydrophobic additive to the dispersion liquid which passed through the said step (6).   The average aspect ratio of the layered inorganic compound present in the liquid crystal phase immediately after the step (2) when measured by a dynamic scattering method is 200 or more, according to any one of claims 1 to 5. A method for producing a solid material.   The method for producing a solid material according to any one of claims 1 to 6, wherein the layered inorganic compound includes a nanosheet having a composition of hectorite synthesized by a melting method.   The method for producing a solid material according to any one of claims 1 to 6, wherein the layered inorganic compound includes a nanosheet having a composition of synthetic mica synthesized by a melting method.