WO2020261901A1

WO2020261901A1 - Gel producing method and gel producing apparatus

Info

Publication number: WO2020261901A1
Application number: PCT/JP2020/021844
Authority: WO
Inventors: 室伏　英伸
Original assignee: Ａｇｃ株式会社
Priority date: 2019-06-28
Filing date: 2020-06-02
Publication date: 2020-12-30
Also published as: JP2022123156A

Abstract

Provided is a gel producing method in which a gel raw material solution is continuously supplied from above a flexible conveyance sheet which is moving, and the raw material solution is formed into a ribbon shape and gelled on the conveyance sheet.

Description

Gel manufacturing method and gel manufacturing equipment

The present disclosure relates to a gel manufacturing method and a gel manufacturing apparatus.

Patent Document 1 discloses a method for continuously producing a wet gel. According to this method, while continuously pouring the second liquid material onto the first liquid layer, the second liquid material formed on the first liquid layer is formed with the second liquid material. It is continuously moved on the first liquid layer so as to move away from the pouring position. The second liquid layer is continuously gelled while the second liquid layer is continuously moved on the first liquid layer, and the formed wet gel is continuously transferred from above the first liquid layer. Extract.

International Publication No. 2019/0464669

When the raw material liquid A of the gel is supplied onto the liquid layer B having a higher density than the raw material liquid A, a layer of the raw material liquid A is formed on the liquid layer B. If the liquid layer B is sufficiently wider than the layer of the raw material liquid A, the thickness of the layer of the raw material liquid A naturally tends to be constant. The thickness is also called the equilibrium thickness. The equilibrium thickness _HA0 is obtained from the following equation (1).

Equilibrium thickness _H A0 (m), as shown in the equation (1), and the density of the raw material solution A [rho _A (kg / ^{m 3),} the density [rho _B of the liquid layer B and (kg / ^{m 3),} the raw material a liquid surface tension of _{a σ a (N / m)} , and the surface tension of the liquid layer _{B σ B (N / m)} , and the surface tension of the raw material liquid a and liquid layer _{B σ a-B (N /} m) Is required from. In the above equation (1), "g" is the gravitational acceleration, which is 9.8 (m / s ² ).

The equilibrium thickness _HA0 is determined by the combination of the material of the raw material liquid A and the material of the liquid layer B. The thickness of the raw material liquid A can be changed by applying a force to the layer of the raw material liquid A on the liquid layer B, but the control of the applied force is complicated.

On the other hand, in the case of the batch type, the raw material liquid A is put into the inside of the container, and the raw material liquid A is gelled inside the container. After that, when the gelled gel was taken out from the container, the gel sometimes cracked.

One aspect of the present disclosure provides a technique for easily adjusting the thickness of the gel and suppressing the gel from cracking.

[1] In the method for producing a gel according to one aspect of the present disclosure, a raw material liquid for gel is continuously supplied from above to a moving flexible transport sheet, and the raw material liquid is spread on the transport sheet. It is molded into a ribbon and gels.

[2] In the method according to the above [1], the transport sheet has a cross section orthogonal to the moving direction of the transport sheet, and has a flat portion and an upper surface of the flat portion in a moving direction of the transport sheet. It has a pair of bank portions formed at intervals in the width direction orthogonal to.

[3] In the method according to the above [1], the transport sheet has a cross section orthogonal to the moving direction of the transport sheet, and has a flat portion and an upper surface of the flat portion on the moving direction of the transport sheet. It has a pair of surface-modified portions having a surface tension smaller than that of the flat portion, which are formed at intervals in the width direction orthogonal to the above.

[4] The method according to any one of [1] to [3] above, in which the transport sheet is bent at a position downstream of the position where the raw material liquid is supplied in the transport direction of the raw material liquid. , The transport sheet is continuously peeled from the ribbon-shaped gel.

[5] The method according to the above [4], further, the ribbon-shaped gel continuously peeled from the transport sheet and the support sheet that supports the ribbon-shaped gel from below are merged. , The ribbon-shaped gel and the support sheet are continuously conveyed.

[6] The method according to any one of [1] to [5] above, and further, while the ribbon-shaped gel passes through the enclosed region, the ribbon-shaped gel. The solvent contained inside the ribbon is replaced with another solvent.

[7] The method according to any one of [1] to [6] above, and further, while the ribbon-shaped gel passes through the enclosed region, the ribbon-shaped gel. Remove the solvent contained inside the ribbon.

[8] The ribbon-shaped gel that has passed through the region for removing the solvent according to the method according to the above [7] is wound into a roll.

[9] The method according to any one of the above [1] to [8], wherein the transport sheet is floated on a liquid layer, and the raw material liquid is floated on the transport sheet floated on the liquid layer. It is molded into the ribbon shape and gelled.

[10] The gel manufacturing apparatus according to one aspect of the present disclosure is a flexible transfer sheet that supports and moves the raw material solution of the gel from below, and the raw material solution is continuously provided from above with respect to the transfer sheet. It has a raw material liquid supply unit for supplying to.

[11] In the apparatus according to the above [10], the transport sheet has a cross section orthogonal to the moving direction of the transport sheet, and has a flat portion and an upper surface of the flat portion on the moving direction of the transport sheet. It has a pair of bank portions formed at intervals in the width direction orthogonal to.

[12] In the apparatus according to the above [10], the transport sheet has a cross section orthogonal to the moving direction of the transport sheet, and has a flat portion and an upper surface of the flat portion on the moving direction of the transport sheet. It has a pair of surface-modified portions having a surface tension smaller than that of the flat portion, which are formed at intervals in the width direction orthogonal to the above.

[13] The apparatus according to any one of the above [10] to [12], and further gels the raw material liquid at a position downstream of the raw material liquid supply unit in the transport direction of the raw material liquid. It has a sheet peeling portion that continuously peels the conveyed sheet from the formed ribbon-shaped gel.

[14] The device according to the above [13], the transport sheet is an endless belt circulated between the sheet peeling portion and the raw material liquid supply portion.

[15] The apparatus according to the above [13] or [14], further, the ribbon-shaped gel continuously peeled from the transport sheet, and a support sheet for supporting the ribbon-shaped gel from below. It has a delivery unit that sends out the support sheet toward the confluence point with.

[16] The apparatus according to any one of the above [10] to [15], further comprising a winding portion for winding a ribbon-shaped gel obtained by gelling the raw material liquid into a roll shape.

[17] The device according to any one of the above [10] to [16], further comprising a storage portion for the liquid layer for accommodating the liquid layer for floating the transport sheet.

According to one aspect of the present disclosure, the thickness of the gel can be easily adjusted and the gel can be prevented from cracking.

FIG. 1 is a cross-sectional view showing a gel manufacturing apparatus according to an embodiment. FIG. 2 is a cross-sectional view showing a first modification of the molded portion shown in FIG. FIG. 3A is a cross-sectional view showing a first example of the transport sheet. FIG. 3B is a cross-sectional view showing a second example of the transport sheet. FIG. 3C is a cross-sectional view showing a third example of the transport sheet. FIG. 3D is a cross-sectional view showing a fourth example of the transport sheet. FIG. 4 is a flowchart showing a method for producing a gel according to an embodiment. FIG. 5 is a cross-sectional view showing a second modification of the molded portion shown in FIG. FIG. 6 is a plan view showing the accommodating portion shown in FIG. FIG. 7 is a cross-sectional view showing a manufacturing apparatus according to a modified example.

First, the terms used in the present specification and the claims will be described. "Gel" includes both "wet gel" and "xerogel".

"Wet gel" means a gel in which the three-dimensional network is swollen by a swelling agent. It includes hydrogels in which the swelling agent is water, alcohol gels in which the swelling agent is alcohol, and organogels in which the swelling agent is an organic solvent.

"Xerogel" is a technical term for the structure and process of sol, gel, mesh, and inorganic-organic composite materials of the "International Union of Pure and Applied Chemistry (IUPAC) Inorganic Chemistry Subcommittee and Polymer Subcommittee, Polymer Terminology Subcommittee". According to the definition (IUPAC Recommendation 2007), it means "a gel consisting of an open network formed by removing a swelling agent from a gel." There is also a classification method in which the swelling agent is removed by supercritical drying as airgel, the swelling agent removed by normal evaporation drying as xerogel, and the swelling agent removed by freeze-drying as cryogel. In the scope of claims, these are collectively referred to as xerogel.

"Surface tension" is the force acting on the boundary between a liquid or solid and a gas (for example, air).

“～” Indicates a numerical range means that the numerical values before and after it are included as the lower limit value and the upper limit value.

The X-axis direction, Y-axis direction, and Z-axis direction are perpendicular to each other. The X-axis direction and the Y-axis direction are horizontal directions, and the Z-axis direction is a vertical direction.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each drawing, the same or corresponding configurations may be designated by the same reference numerals and description thereof may be omitted.

(Gel manufacturing equipment)
FIG. 1 is a cross-sectional view showing a gel manufacturing apparatus according to an embodiment. As shown in FIG. 1, the gel manufacturing apparatus 1 includes a molding section 2, a take-out section 3, a solvent replacement section 4, a relay section 5, a drying section 6, and a winding section 7. The molding unit 2 molds the raw material liquid A of the gel C into a ribbon shape and gels it. The ribbon shape is a sheet shape. The take-out part 3 takes out the ribbon-shaped gel C from the molding part 2. The solvent replacement unit 4 replaces the solvent contained inside the gel C with another solvent. The relay unit 5 conveys the gel C from the solvent replacement unit 4 to the drying unit 6. The drying unit 6 removes the solvent contained inside the gel C. The winding unit 7 winds the gel C that has passed through the drying unit 6 in a roll shape.

Since the manufacturing apparatus 1 is in-lined and a series of processes are carried out all at once, the ribbon-shaped gel C can be efficiently manufactured. The molding section 2, the taking-out section 3, the solvent replacing section 4, the relay section 5, the drying section 6, and the winding section 7 are arranged in this order along the passage of the ribbon-shaped gel C. The ribbon-shaped gel C continuously continues from the molding portion 2 to the winding portion 7. Since the gel C continues uninterrupted, there is no need to move the gel C extra between steps, and no extra operation or work is required. Therefore, it is possible to prevent unintended deformation when the gel C is moved excessively between steps, and it is possible to prevent the gel C from cracking.
The gel C of the present embodiment continuously continues from the molding portion 2 to the winding portion 7, but the technique of the present disclosure is not limited to this. For example, the gel C does not have to reach the winding section 7 by continuing from the molding section 2 to the drying section 6. Further, the gel C does not have to reach the drying portion 6 by continuing from the molding portion 2 to the solvent substitution portion 4. In any case, if it is a continuous type, it is possible to suppress the gel C from cracking.

The manufacturing apparatus 1 may be installed in a clean room in order to suppress the mixing of foreign substances into the gel C.

(Molding part)
The molding unit 2 has a transport sheet 11 that supports the raw material liquid A of the gel C from below and moves, and a raw material liquid supply section 22 that continuously supplies the raw material liquid A to the transport sheet 11 from above. The raw material liquid supply unit 22 is arranged above the transport path of the transport sheet 11, and supplies the raw material liquid A over the entire width direction orthogonal to the transport direction, which is the movement direction of the transport sheet 11. The raw material liquid A is supplied from above to the transport sheet 11 that moves in the horizontal direction or the oblique direction.

The transport sheet 11 has a strip shape and is transported in the longitudinal direction thereof. The raw material liquid A is supplied onto, for example, a horizontal transport sheet 11, is formed in a ribbon shape on the horizontal transport sheet 11, and is gelled. The raw material liquid A may be supplied onto the transport sheet 11 inclined with respect to the horizontal plane, formed in a ribbon shape on the inclined transport sheet 11, and may be gelled.

The transport sheet 11 is bent at a position downstream of the position where the raw material liquid A is supplied in the transport direction of the raw material liquid A, and is continuously peeled from the gel C. Since the gel C and the transport sheet 11 can be opened in a wedge shape while supporting the gel C flatly, the stress acting on the gel C can be reduced and the gel C can be suppressed from cracking.

The peeling of the transport sheet 11 and the gel C may be performed after the transport sheet 11 is wound together with the gel C in a roll shape, that is, may be performed when the transport sheet 11 is unwound from the roll shape. Good. The gel C can be prevented from cracking by performing the same peeling operation regardless of the time when the peeling is performed.

Further, the molding unit 2 has a sheet supply unit 12 that supplies the transport sheet 11 toward the raw material liquid supply unit 22. The sheet supply unit 12 has a supply roller 121, and the supply roller 121 rotates to feed out a transport sheet 11 previously wound around the outer periphery thereof. The sheet supply unit 12 may further have a direction changing roller 122 that changes the moving direction of the conveying sheet 11 along the outer periphery thereof by rotating. The number and position of the direction changing rollers are not particularly limited.

The supply core 123 may be detachably attached to the outer circumference of the supply roller 121. If a plurality of supply cores 123 are prepared, the transfer sheet 11 can be wound around another supply core 123 while the transfer sheet 11 is fed out from one supply core 123. Therefore, the roll-shaped transport sheet 11 can be prepared in advance, and the waiting time can be shortened. Further, the transport sheet 11 can be transported in a state of being wound around the supply core 123, and the shape can be prevented from being lost during the transport.

The outer circumference of the supply roller 121 may be provided with irregularities. Due to the unevenness, slippage of the supply core 123 (however, the transport sheet 11 when the supply core 123 is not provided) can be suppressed. Similarly, the outer circumference of the supply core 123 may be provided with irregularities. The unevenness can suppress the slip of the transport sheet 11.

The material of the supply roller 121 is not particularly limited, but is, for example, metal or resin. The resin is excellent in light weight and excellent transportability. Non-slip rubber may be attached to the outer circumference of the supply roller 121.

Similarly, the material of the supply core 123 is not particularly limited, but is, for example, metal or resin. The resin is excellent in light weight and excellent transportability. Non-slip rubber may be attached to the outer periphery of the supply core 123.

Further, the molding unit 2 has a sheet peeling portion 13 that bends the transport sheet 11 and peels the transport sheet 11 from the gel C at a position downstream of the position where the raw material liquid A is supplied in the transport direction of the raw material liquid A. The transport sheet 11 peeled off from the gel C can be reused. As described above, the transport sheet 11 may be sent to the winding unit 7 together with the gel C and wound in a roll shape together with the gel C without being peeled off from the gel C.

The sheet peeling portion 13 has, for example, a peeling roller 131 around which the transport sheet 11 is wound so as to peel off from the gel C, and a recovery roller 132 for collecting the transport sheet 11 from the peel roller 131. The transport sheet 11 is curved along the outer circumference of the release roller 131 to change the moving direction. The peeling roller 131 is a direction changing roller that changes the moving direction of the transport sheet 11 along the outer circumference thereof by rotating. On the other hand, the recovery roller 132 winds the transport sheet 11 around its outer circumference by rotating.

A recovery core 133 may be detachably attached to the outer circumference of the recovery roller 132. The transport sheet 11 is wound around the outer circumference of the recovery core 133. The roll-shaped transport sheet 11 is removed from the recovery roller 132 together with the recovery core 133. Therefore, it is possible to prevent the shape from being lost during removal and subsequent transportation.

The outer circumference of the recovery roller 132 may be provided with irregularities. Due to the unevenness, slippage of the recovery core 133 (however, if the recovery core 133 is not provided, the transport sheet 11) can be suppressed. Similarly, the outer circumference of the recovery core 133 may be provided with irregularities. The unevenness can suppress the slip of the transport sheet 11.

The material of the recovery roller 132 is not particularly limited, but is, for example, metal or resin. The resin is excellent in light weight and excellent transportability. Non-slip rubber may be attached to the outer circumference of the recovery roller 132.

Similarly, the material of the recovery core 133 is not particularly limited, but is, for example, metal or resin. The resin is excellent in light weight and excellent transportability. Non-slip rubber may be attached to the outer periphery of the recovery core 133.

The recovery core 133 may be removed from the recovery roller 132 with the transport sheet 11 wound around the outer circumference thereof, and then attached to the supply roller 121 as the supply core 123. Similarly, the supply core 123 may be removed from the supply roller 121 after feeding out the transport sheet 11, and then attached to the recovery roller 132 as the recovery core 133.

The sheet peeling portion 13 may have only the peeling roller 131, and the peeling roller 131 may also serve as the recovery roller 132. That is, the transport sheet 11 may be wound around the outer circumference of the release roller 131. In this case, the peeling roller 131 is actively rotated by the rotary motor.

When the peeling roller 131 and the recovery roller 132 are provided separately, the recovery roller 132 is actively rotated by the rotary motor. The peeling roller 131 may rotate actively, but in the present embodiment, it rotates passively. Further, the supply roller 121 and the direction change roller 122 may also be actively rotated, but in the present embodiment, they are passively rotated.

FIG. 2 is a cross-sectional view showing a modified example of the manufacturing apparatus shown in FIG. In this modification, the transport sheet 11 is an endless belt and is hung around the supply roller 121, the direction change roller 122, the release roller 131, and the recovery roller 132. In this modification, not only the direction changing roller 122 and the peeling roller 131 but also the supply roller 121 and the recovery roller 132 are direction change rollers. The number of the direction changing rollers may be two or more, and the transport sheet 11 may be hung only on the direction changing rollers 122 and the peeling rollers 131 shown in FIG. At least one of the plurality of direction changing rollers (for example, the peeling roller 131) is actively rotated by a rotary motor. All of the plurality of directional rollers may rotate actively, but some of the directional rollers may rotate passively.

The transport sheet 11 is circulated between the sheet peeling section 13 and the sheet supply section 12, and is circulated between the sheet peeling section 13 and the raw material liquid supply section 22. It is possible to save the trouble of attaching the roll-shaped transport sheet 11 to the supply roller 121 and removing the roll-shaped transport sheet 11 from the collection roller 132. Further, the supply core 123 and the recovery core 133 shown in FIG. 1 are unnecessary.

The transport sheet 11 may have a single-layer structure or a multi-layer structure. If the transport sheet 11 has a multi-layer structure, damage to the gel C can be prevented and the durability of the transport sheet 11 can be improved. For example, the layer in contact with the gel C may be, for example, a flexible, smooth, seamless resin film to prevent damage to the gel C. Further, the layer in contact with various rollers may be a rubber belt or a resin belt usually used in a belt conveyor or the like in order to improve the durability of the transport sheet 11.

By the way, the molding and gelation of the raw material liquid A is carried out on the transport sheet 11 as described above. Since the transport sheet 11 is a solid, the raw material liquid A naturally becomes thin and easily spreads. Further, since the transport sheet 11 is a solid, the width of the raw material liquid A can be determined by the shape and the like.

Once the width of the raw material liquid A is determined, the thickness of the raw material liquid A is determined by the moving speed of the transport sheet 11 and the supply speed of the raw material liquid A. Since the moving speed of the transport sheet 11 and the supply speed of the raw material liquid A can be easily changed, the thickness of the raw material liquid A and thus the thickness of the gel C can be easily changed.

FIG. 3A is a cross-sectional view showing a first example of the transport sheet. The transport sheet 11 according to the first example has a cross section orthogonal to the moving direction (X-axis direction) of the transport sheet 11, and has a width orthogonal to the moving direction of the transport sheet 11 on the flat portion 111 and the upper surface of the flat portion 111. It has a pair of bank portions 112 formed at intervals in the direction (Y-axis direction).

The raw material liquid A is supplied to the groove formed by the flat portion 111 and the pair of bank portions 112. The pair of bank portions 112 prevent the raw material liquid A from spreading in the width direction, and determine the width of the raw material liquid A. The height of the bank portion 112 may be smaller than the thickness of the raw material liquid A, but may be larger than the thickness of the raw material liquid A in order to surely prevent the raw material liquid A from spreading in the width direction.

The greater the surface tension of the flat portion 111, the thinner the raw material liquid A gets wet and spreads, and the thinner the gel C can be produced. Of course, it is also possible to produce a thick gel C. The surface tension of the flat portion 111 is preferably larger than the surface tension of the raw material liquid A. Specific examples of the material of such a flat portion 111 include polyester and nylon.

The material of the bank portion 112 may be the same as the material of the flat portion 111. If the bank portion 112 and the flat portion 111 are made of the same material, the bank portion 112 and the flat portion 111 can be integrally formed, and the manufacturing cost of the transport sheet 11 can be reduced. Therefore, the surface tension of the bank portion 112 may be larger than the surface tension of the raw material liquid A.

When the surface tension of the bank portion 112 is larger than the surface tension of the raw material liquid A, a concave Meniscus is formed on the liquid surface of the raw material liquid A as shown in FIG. 3A. When the raw material liquid A is gelled in this state, sharp burrs are generated at the corners of the gel C. Since the burrs are small and the thickness of the gel C is uniform as a whole, the burrs may be left as they are, or may be cut off and removed. However, if burrs are chipped or cracks occur when the gel C and the transport sheet 11 are peeled off, the gel C may be cracked at that point.

Therefore, the transport sheet 11 according to the second example shown in FIG. 3B has a surface modification portion 113 on the side wall surface on the inner side in the width direction of the bank portion 112. The surface tension of the surface modification portion 113 is smaller than the surface tension of the bank portion 112 and the flat portion 111, preferably less than or equal to the surface tension of the raw material liquid A, and more preferably smaller than the surface tension of the raw material liquid A.

When the surface tension of the surface modifying portion 113 is smaller than the surface tension of the raw material liquid A, the surface modifying portion 113 repels the raw material liquid A as shown in FIG. 3B, so that the upwardly convex meniscus is the liquid of the raw material liquid A. Formed on the surface. When the raw material liquid A is gelled in this state, an obtuse chamfered portion is formed at the corner portion of the gel C. Therefore, it is possible to prevent the corners of the gel C from being chipped when the gel C and the transport sheet 11 are peeled off.

However, the effect of suppressing the corners of the gel C from being chipped can be obtained if the surface tension of the surface modification portion 113 is smaller than the surface tension of the bank portion 112 and the flat portion 111. By making a difference in surface tension between the flat portion 111 and the surface modification portion 113, a thin gel C can be produced, and chipping of the corners of the gel C can be suppressed.

The surface modification portion 113 may be a solid film or a liquid film. Specific examples of the solid film include a coating film made of a fluororesin. Specific examples of the liquid film include a fluorine-based oil coating film and a silicone oil coating film. The surface modification portion 113 is preferably a solid film from the viewpoint of durability and stability. Since the surface modification section 113 repels the raw material liquid A, it also serves as a release agent for the gel C.

In the second example shown in FIG. 3B, the flat portion 111 and the bank portion 112 are formed of the same material, and the surface modification portion 113 is formed on the side wall surface on the inner side in the width direction of the bank portion 112. The flat portion 111 and the bank portion 112 may be formed of different materials, and the surface tension of the bank portion 112 may be smaller than the surface tension of the flat portion 111. Also in this case, a thin gel C can be produced, and chipping of the corners of the gel C can be suppressed.

By the way, in the first example shown in FIG. 3A and the second example shown in FIG. 3B, the side wall surface on the inner side in the width direction of the bank portion 112 is perpendicular to the upper surface of the flat portion 111. On the other hand, in the third example shown in FIG. 3C, the side wall surface on the inner side in the width direction of the bank portion 112 is inclined with respect to the upper surface of the flat portion 111, and specifically, the lateral side in the width direction is directed upward. Tilt to. Due to this inclination, the gel C and the transport sheet 11 can be easily peeled off. The contents of the first example shown in FIG. 3A and the second example shown in FIG. 3B can also be applied to the third example shown in FIG. 3C.

FIG. 3D is a cross-sectional view showing a fourth example of the transport sheet. The transport sheet 11 of the fourth example has a surface modification portion 115 shown in FIG. 3D instead of the bank portion 112 shown in FIGS. 3A to 3C. A pair of surface modification portions 115 are formed on the upper surface of the flat portion 111 at intervals in the width direction (Y-axis direction).

The raw material liquid A is supplied between the pair of surface modification portions 115 on the upper surface of the flat portion 111. The surface tension of the surface modification portion 115 is smaller than the surface tension of the flat portion 111, preferably smaller than the surface tension of the raw material liquid A. The pair of surface modification portions 115 prevent the raw material liquid A from spreading in the width direction, and determine the width of the raw material liquid A.

The surface modification portion 115 may be a solid film or a liquid film. Specific examples of the solid film include a coating film made of a fluororesin. Specific examples of the liquid film include a fluorine-based oil coating film and a silicone oil coating film. The surface modification portion 115 is preferably a solid film from the viewpoint of durability and stability.

The thickness of the surface modification portion 115 may be thicker than the thickness of the raw material liquid A, but may be thinner. Even if the thickness of the surface modification portion 115 is about 1 nm, leakage of the raw material liquid A having a thickness of about 1 mm can be prevented.

The thickness of the surface modification portion 115 may be thicker than the thickness of the gel C, but may be thinner. If the thickness of the surface modification portion 115 is thinner than the thickness of the gel C, the transport sheet 11 can be easily wound together with the gel C in a roll shape. This is because the gel C and the flat portion 111 are repeatedly laminated without a gap at the time of winding.

Further, if the thickness of the surface modification portion 115 is thinner than the thickness of the gel C, the thickness of the surface modification portion 115 is thin and the variation in the thickness of the transfer sheet 11 is small, so that the transfer sheet after peeling from the gel C is small. It is easy to wind 11 by itself into a roll.

The material of the transport sheet 11 is appropriately selected according to the solvent of the raw material liquid A. The material of the transport sheet 11 is not particularly limited, but a resin is preferable from the viewpoint of flexibility. Specific examples of the transport sheet 11 include a polyester film and a nylon film. It is preferable to use a transport sheet 11 which does not deteriorate or swell due to the raw material liquid A and does not react with each other so that the layer of the raw material liquid A is stably present on the transport sheet 11.

The gel C obtained in the molding unit 2 is a wet gel containing a solvent as a swelling agent. The thickness of the wet gel is, for example, 0.1 mm to 20 mm, preferably 0.5 mm to 10 mm. The wet gel is dried in the drying section 6 to become a xerogel. The thickness of the xerogel is, for example, 0.1 mm to 20 mm, preferably 0.5 mm to 10 mm. The xerogel may be a porous monolith that is transparent and heat insulating. Xerogel having transparency and heat insulating property is used as a transparent heat insulating material in, for example, window glass for automobiles and window glass for buildings.

When the use of xerogel is a transparent heat insulating material, the transmittance of xerogel at a wavelength of 500 nm is preferably 70% or more, preferably 80% or more, and preferably 90% or more in terms of thickness of 1 mm. The transmittance is measured in accordance with the Japanese Industrial Standards (JIS R 3106: 1998).

Examples of applications of xerogel include filters, adsorbents, sound absorbing materials, moisture absorbing materials, oil absorbing materials, and separation membranes, in addition to heat insulating materials. Xerogel may not be transparent or may be opaque depending on the application.

The type of xerogel is (1) polysiloxane xerogel in the present embodiment, but may be (2) polymer xerogel or (3) polysaccharide xerogel such as cellulose xerogel.

The raw material liquid A contains, for example, a raw material for gel C (hereinafter, also referred to as “gel raw material”) and a solvent for dissolving the gel raw material. The gel raw material is appropriately selected according to the type of xerogel finally obtained. The solvent is, for example, water or an organic solvent. Examples of the organic solvent include alcohols (methanol, ethanol, isopropyl alcohol, tert-butyl alcohol, benzyl alcohol, etc.), aprotic polar organic solvents (N, N-dimethylformamide, dimethylsulfoxide, N, N-dimethylacetamide, etc.), Examples thereof include ketones (cyclopentanone, cyclohexanone, methylethylketone, methylisobutylketone, acetone, etc.), hydrocarbons (n-hexane, heptane, etc.) and the like.

When the xerogel is (1) polysiloxane xerogel, examples of the gel raw material include those containing (1A) a silane compound and (1B) a catalyst. (1B) The catalyst is for uniformly promoting gelation. The gel raw material may further contain (1C) a surfactant.

Examples of the silane compound include alkoxysilane, a 6-membered ring-containing silane compound having a 6-membered ring-containing skeleton and a hydrolyzable silyl group, and a silyl group-containing polymer having an organic polymer skeleton and a hydrolyzable silyl group. Can be mentioned.

Examples of the alkoxysilane include tetraalkoxysilane (tetramethoxysilane, tetraethoxysilane, etc.), monoalkyltrialkoxysilane (methyltrimethoxysilane, methyltriethoxysilane, etc.), and dialkyldialkoxysilane (dimethyldimethoxysilane, dimethyldiethoxysilane, etc.). Etc.), trimethoxyphenylsilane, compounds having alkoxysilyl groups at both ends of the alkylene group (1,6-bis (trimethoxysilyl) hexane, 1,6-bis (methyldimethoxysilyl) hexane, 1,6-bis (Methyldiethoxysilyl) hexane, 1,2-bis (trimethoxysilyl) ethane, 1,2-bis (methyldimethoxysilyl) ethane, 1,2-bis (methyldiethoxysilyl) ethane, etc.), perfluoropolyether Alkoxysilane having a group (perfluoropolyether triethoxysilane, perfluoropolyether methyldiethoxysilane, etc.), alkoxysilane having a perfluoroalkyl group (perfluoroethyltriethoxysilane, etc.), pentafluorophenylethoxydimethylsilane, trimethoxy (3, 3,3-Trifluoropropyl) Alkoxy, Alkoxysilane with Vinyl Group (Vinyltrimethoxysilane, Vinyltriethoxysilane, Dimethoxymethylvinylsilane, Diethoxymethylvinylsilane, etc.), Alkoxysilane with Allyl Group (Allyltrimethoxysilane, etc.) Allyldimethoxymethylsilane, allyldiethoxymethylsilane, etc.), alkoxysilane with an epoxy group (2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxy) (Propylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, etc.), alkoxysilane having an acryloyloxy group (3-acryloyloxypropyltrimethoxysilane, 3-acryloyloxypropylmethyldimethoxysilane, etc.), methacryloyloxy group Examples thereof include an alkoxysilane (3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, etc.) and the above-mentioned alkoxysilane oligomer.

The 6-membered ring-containing skeleton in the 6-membered ring-containing silane compound is an organic skeleton having at least one 6-membered ring selected from the group consisting of an isocyanul ring, a triazine ring and a benzene ring.

The organic polymer skeleton of the silyl group-containing polymer is an organic skeleton having at least one chain selected from the group consisting of polyethylene chains, polyether chains, polyester chains and polycarbonate chains.

Examples of the (1B) catalyst include a base catalyst and an acid catalyst, and an aqueous solution thereof may be used. Examples of the base catalyst include amines (triethylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, etc.), urea, ammonia, sodium hydroxide, potassium hydroxide and the like. Examples of the acid catalyst include inorganic acids (nitric acid, sulfuric acid, hydrochloric acid, etc.) and organic acids (girate, oxalic acid, acetic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monofluoroacetic acid, trifluoroacetic acid, etc.).

Examples of the (1C) surfactant include hexadecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, Pluronic F127 (trade name of BASF), EH-208 (trade name of NOF Corporation) and the like.

When the xerogel is (2) polymer xerogel, the gel raw material includes a thermoplastic resin, a curable resin, and the like.

Examples of the thermoplastic resin include those capable of dissolving in a solvent when heated and forming a monolith (porous body) when cooled, and specific examples thereof include polymethylmethacrylate and polystyrene.

Examples of the curable resin include a photocurable resin and a thermosetting resin. Examples of the photocurable resin include those containing either one or both of acrylate and methacrylate and a photopolymerization initiator. Examples of the thermosetting resin include those containing either one or both of acrylate and methacrylate and a thermal polymerization initiator, an addition condensate of resorcinol and formaldehyde, and an addition condensate of melamine and formaldehyde. Be done.

When the xerogel is (3) polysaccharide xerogel, examples of the gel raw material include those containing (3A) polysaccharide nanofibers and (3B) acid. Examples of polysaccharides include chitin, chitosan, and gellan gum in addition to cellulose.

Examples of the (3A) polysaccharide nanofiber include 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) oxidized cellulose nanofiber. Examples of the (3A) polysaccharide nanofiber include chitin nanofiber and chitosan nanofiber in addition to cellulose nanofiber.

Examples of the (3B) acid include the inorganic acid and the organic acid. Bases can be used instead of acids.

By the way, when the gel raw material contains (1A) a silane compound and (1B) a catalyst, gelation of the raw material liquid A is performed by heating. The silane compound is hydrolyzed by an acid catalyst or the like to form a sol having a silanol group (Si—OH). When the sol is heated, the silanol groups undergo a dehydration condensation reaction between the molecules to form a Si—O—Si bond, and the raw material liquid A is gelled.

The raw material liquid supply unit 22 includes, for example, a mixing tank for mixing a silane compound and a catalyst. The mixing tank may include a cooling device for cooling the raw material liquid A in order to suppress the progress of gelation. The temperature of the mixing tank is preferably lower from the viewpoint of suppressing the progress of gelation, but may be set higher than the freezing point of the raw material liquid A from the viewpoint of preventing freezing, and is set to, for example, 0 ° C to 20 ° C.

The mixing tank may include a stirring device that stirs the raw material liquid A. The silane compound and the catalyst can be mixed in a short time, and the raw material liquid A can be homogenized in a short time.

Although not shown, the mixing tank is connected to the silane compound supply source via the first pipe, and is connected to the catalyst supply source via the second pipe. The first pipe is provided with a first flow rate controller that controls the flow rate of the silane compound, and the second pipe is provided with a second flow rate controller that controls the flow rate of the catalyst. Since the flow rate of the silane compound and the flow rate of the catalyst can be controlled, the residence time in the mixing tank can be shortened. The flow rate of the silane compound and the flow rate of the catalyst are appropriately determined according to the flow rate of the raw material liquid A supplied on the transport sheet 11.

The molding unit 2 has a first heater 23 and a second heater 24 in order to gel the raw material liquid A on the transport sheet 11. The first heater 23 is arranged above the transport sheet 11 and heats the raw material liquid A from above. The second heater 24 is arranged below the transport sheet 11, and by heating the transport sheet 11, the raw material liquid A is heated from below. By heating the raw material liquid A from both the upper and lower sides, gelation can proceed from both the upper and lower sides.

A plurality of first heaters 23 may be arranged at intervals along the transport direction (X-axis direction) of the transport sheet 11. By independently controlling the plurality of first heaters 23, the temperature distribution in the transport direction of the raw material liquid A can be controlled. The temperature distribution may be uniform over the entire transport direction, may be higher toward the downstream, or may be lower toward the downstream. The second heater 24 may also be arranged and controlled in the same manner as the first heater 23.

The heating method of the first heater 23 and the second heater 24 is not particularly limited, but is appropriately selected from, for example, a resistance heating type, an infrared heating type, an arc heating type, and the like according to the installation location. ..

The molding unit 2 may have at least one of the first heater 23 and the second heater 24. Further, although not shown, the heater may be installed so as to heat from the side surface of the transport sheet 11. Further, the means for gelling the raw material liquid A is not limited to the heater, and is appropriately selected according to the type of the gel raw material.

For example, when the gel raw material is a thermoplastic resin, the means for gelling the raw material liquid A is a cooler. The cooler cools the raw material liquid A on the transport sheet 11 and gels the raw material liquid A. The cooler may be arranged and controlled in the same manner as the heater. Natural cooling may be performed instead of forced cooling by the cooler.

When the gel raw material is a photocurable resin, the means for gelling the raw material liquid A is a light source. The light source irradiates the raw material liquid A existing on the transport sheet 11 with light such as ultraviolet rays to cure the photocurable monomer and gel the raw material liquid A. The light source may be arranged and controlled in the same manner as the heater.

When the gel raw material is a thermosetting resin, the means for gelling the raw material liquid A is a heater.

Further, when the gel raw material is a polysaccharide nanofiber, the polysaccharide nanofiber gels in a short time when it comes into contact with an acid catalyst or a base catalyst. Therefore, the raw material liquid A may contain polysaccharide nanofibers and may not contain an acid catalyst or a base catalyst. The acid catalyst or the base catalyst may be supplied in a shower shape from above to the layer of the raw material liquid A formed on the transport sheet 11. In this case, the means for gelling the raw material liquid A is a feeder that supplies an acid catalyst or a base catalyst to the layer of the raw material liquid A from above.

(Ejection section)
The take-out part 3 continuously takes out the ribbon-shaped gel C from the molding part 2. The take-out portion 3 is arranged on the downstream side of the molding portion 2 and pulls the ribbon-shaped gel C. As shown in FIG. 1, since the take-out portion 3 supports the gel C, the transport sheet 11 can be bent and deformed below the gel C, and the gel C can be continuously fed.

The take-out portion 3 includes, for example, a tension roller 31. For example, the tension roller 31 sandwiches the ribbon-shaped gel C from both the upper and lower sides and rotates the gel C to send the gel C to the downstream side. An upper tension roller 31, the distance between the tension roller 31 of the lower, so that the thickness H _C gel C is not excessively compressed, that is, are set to gel C is not cracked. The thickness _{H C} of the gel C is equal to the final thickness _{H A} raw material liquid A.

Further, the gel C only conveying sheet 11 rather than be passed between the pair of tension rollers 31, and, when the thickness of the bank portion 112 of the transfer sheet 11 is thicker than the thickness H _C of the gel C is a pair tensile rollers 31 sandwiches the transport sheet 11 and sends it out. In this case, the distance between the upper tension roller 31 and the lower tension roller 31 may be slightly smaller than the sum of the thickness of the bank portion 112 and the thickness of the flat portion 111.

Further, gel C only conveying sheet 11 rather than be passed between the pair of tension rollers 31, and the thickness of the surface modification portion 115 of the transfer sheet 11 when thinner than the thickness H _C of the gel C is a pair The tension roller 31 sandwiches the gel C and the transport sheet 11 and feeds them out. In this case, the distance between the upper tension roller 31 and the lower tension roller 31 may be slightly smaller than the sum of the thickness of the gel C and the thickness of the flat portion 111.

The tension roller 31 may not be arranged on both the upper and lower sides of the ribbon-shaped gel C, and may be arranged only on the lower side, for example. The tension roller 31 arranged on the lower side rotates while carrying the ribbon-shaped gel C, and sends the gel C to the downstream side.

The tension roller 31 is made of a metal such as stainless steel, rubber, or a material such as resin. The tension roller 31 may be a metal surface coated with rubber, resin, or the like.

The tension roller 31 may have irregularities on its outer circumference. Due to the unevenness, the slip of the gel C can be suppressed, and the gel C can be reliably sent to the downstream side.

(Solvent replacement part)
The solvent replacement unit 4 replaces the solvent contained inside the ribbon-shaped gel C with another solvent. Gel C is a fine porous body and contains a solvent inside. The solvent substitution is carried out before drying for the purpose of suppressing the shrinkage of the gel C due to the surface tension of the solvent during drying and suppressing the damage of the fine structure of the gel C.

The solvent replacement unit 4 replaces the solvent contained inside the gel C with a solvent suitable for gelation (that is, the solvent of the raw material liquid A) with a solvent suitable for drying. The solvent after the replacement is appropriately selected depending on the drying method. As the drying method, supercritical drying, freeze drying, or atmospheric drying is used.

In supercritical drying, the solvent contained inside the gel C is replaced with a supercritical fluid. As a solvent suitable for supercritical drying, for example, methanol, ethanol, isopropyl alcohol and the like are used. As the supercritical fluid, carbon dioxide gas in a supercritical state is generally used. Supercritical drying is carried out inside a closed high-pressure container.

In freeze-drying, the solvent contained inside the gel C is frozen and then evaporated in a vacuum. This is usually called sublimation. As a solvent suitable for freeze-drying, water, tert-butyl alcohol, cyclohexane, 1,4-dioxane, a fluorine-based solvent and the like are used. Freeze-drying is carried out inside a closed vacuum vessel.

Normal pressure drying evaporates the solvent contained inside the gel C under normal pressure. Since it is important to reduce the contraction force of the fine skeleton of gel C due to the capillary force accompanying solvent evaporation, a solvent suitable for atmospheric drying is a solvent having a small surface tension, for example, a low molecular weight aliphatic such as hexane or heptane. A hydrocarbon solvent or a fluorine solvent is used. Since normal pressure drying is performed at normal pressure, a closed container is not required. Therefore, when the ribbon-shaped gel C continues from the molding portion 2 to the drying portion 6, atmospheric drying is adopted.

The solvent replacement unit 4 forms a passage through which the ribbon-shaped gel C continuously taken out from the molding unit 2 passes, and replaces the solvent contained inside the gel C with a solvent suitable for atmospheric drying. .. Specifically, the solvent replacement unit 4 replaces the solvent contained inside the gel C with a solvent having a surface tension smaller than that of the raw material liquid A from the solvent of the raw material liquid A.

Solvent substitution is carried out at a temperature below the boiling point of the solvent in order to prevent the microstructure of the gel from being damaged by boiling of the solvent. However, in order to increase the solvent replacement efficiency, the solvent may be heated at a temperature below the boiling point. The heating temperature is, for example, 40 ° C to 100 ° C.

The number of times the solvent is replaced is once in this embodiment, but it may be a plurality of times. That is, the solvent contained inside the gel C is replaced with a first solvent different from the solvent of the raw material liquid A from the solvent of the raw material liquid A, and further, a solvent of the raw material liquid A and a second solvent different from the first solvent. May be replaced with.

When the compatibility between the solvent of the raw material liquid A and the second solvent is low, the substitution efficiency becomes poor. Therefore, by temporarily introducing the substitution with the first solvent in the meantime, the solvent of the raw material liquid A can be seconded. The time required for replacement with a solvent can be shortened. As the first solvent, a solvent having high compatibility with both the solvent of the raw material liquid A and the second solvent is used.

The solvent replacement unit 4 has, for example, a storage tank 41 for storing a solvent in which the ribbon-shaped gel C is immersed. When the gel C passes through the inside of the solvent stored in the storage tank 41, the solvent contained in the gel C is replaced with the solvent stored in the storage tank 41 from the solvent of the raw material liquid A according to the natural law of diffusion. Will be done.

A support roller 42 that supports the gel C may be arranged inside the storage tank 41. The number of support rollers 42 may be one or more, and in the case of a plurality of support rollers 42, they are arranged at intervals along the passage of the gel C. The support roller 42 may be actively rotated by a rotation motor or the like, or may be passively rotated.

The passage of the gel C does not have a U-shaped folded portion inside the storage tank 41 in the present embodiment, but may have a U-shaped folded portion. A support roller 42 is arranged at the folded-back portion, the gel C is curved along the outer circumference of the support roller 42, and the moving direction of the gel C is reversed. When the length of the storage tank 41 is the same, the residence time of the gel C inside the storage tank 41 can be lengthened. Further, when the residence time of the gel C inside the storage tank 41 is the same, the length of the storage tank 41 can be shortened and the storage tank 41 can be miniaturized.

The liquid overflowing from the storage tank 41 may be collected and recycled. Since the liquid overflowing from the storage tank 41 contains the solvent of the raw material liquid A and the like, it may be purified by means such as distillation before being recycled. By purification, the solvent, catalyst, surfactant and the like of the raw material liquid A can be removed.

The solvent replacement unit 4 may have a solvent supply unit 43 that supplies a shower-like solvent to the ribbon-shaped gel C from above. Since the shower-like solvent is supplied from above, the immersion depth of the gel C can be made shallow. Since the radius of curvature of the passage of the gel C is large and the bending stress of the gel C is small, it is possible to suppress the gel C from cracking.

When the solvent replacement unit 4 has the solvent supply unit 43, it does not have to have the storage tank 41. Without the storage tank 41, the passage of gel C can be straightened. Since the bending stress of the gel C becomes zero, it is possible to further suppress the gel C from cracking.

When the solvent of the raw material liquid A is suitable for drying, the solvent replacement is not necessary, so that the manufacturing apparatus 1 does not have to have the solvent replacement part 4.

(Relay part)
The relay unit 5 conveys the ribbon-shaped gel C from the solvent replacement unit 4 to the drying unit 6. The speed at which the gel C is conveyed by the relay unit 5 is set so that the gel C passes through the inside of the solvent stored in the storage tank 41, and the gel C flexes downward convexly inside the storage tank 41. Will be done.

The relay unit 5 includes, for example, a relay roller 51. The relay roller 51 is actively rotated by a rotary motor or the like to send the gel C to the downstream side. Since the relay roller 51 is configured in the same manner as the tension roller 31, the description thereof will be omitted.

(Dry part)
The drying unit 6 removes the solvent contained inside the gel C. As the method for drying the gel C, as described above, supercritical drying, freeze drying, or atmospheric drying is used, but in the present embodiment, atmospheric drying suitable for in-line is used.

The drying portion 6 forms a passage through which the ribbon-shaped gel C continuously taken out from the molding portion 2 passes, and removes the solvent contained in the gel C by atmospheric pressure drying. The drying unit 6 has, for example, a drying furnace 61 that forms a passage through which the gel C passes.

A support roller 62 for supporting the gel C may be arranged inside the drying furnace 61. The number of support rollers 62 may be one or more, and in the case of a plurality of support rollers 62, the support rollers 62 are arranged at intervals along the passage of the gel C. The support roller 62 may be actively rotated by a rotation motor or the like, or may be passively rotated.

The passage of the gel C does not have a U-shaped folded portion inside the drying oven 61 in the present embodiment, but may have a U-shaped folded portion. A support roller 62 is arranged at the folded-back portion, the gel C is curved along the outer circumference of the support roller 62, and the moving direction of the gel C is reversed. When the length of the drying oven 61 is the same, the residence time of the gel C inside the drying oven 61 can be lengthened. Further, when the residence time of the gel C inside the drying furnace 61 is the same, the length of the drying furnace 61 can be shortened and the drying furnace 61 can be miniaturized.

Drying of gel C is carried out at a temperature below the boiling point of the solvent in order to prevent the fine structure of the gel from being damaged by boiling of the solvent. However, in order to increase the solvent removal efficiency, the gel C may be heated at a temperature below the boiling point. The drying temperature of gel C is, for example, room temperature to 100 ° C.

The drying unit 6 may have a heater 63 for heating the gel C. A plurality of heaters 63 may be arranged on both the upper and lower sides of the gel C passage, and may be arranged at intervals along the gel C passage. The heater 63 is arranged inside the drying furnace 61.

The heating method of the heater 63 is not particularly limited, but is appropriately selected from, for example, a resistance heating type and an infrared heating type, depending on the installation location.

The drying unit 6 may have a blower (not shown) that blows air to the gel C. By sending wind to the gel C, the evaporation of the solvent contained inside the gel C can be promoted. The solvent evaporated in the drying unit 6 is recovered and discarded or recycled as needed.

The gel C obtained in the dry portion 6 is a xerogel, which is a porous monolith.

(Winding section)
The winding unit 7 winds the ribbon-shaped gel C that has passed through the drying unit 6 into a roll shape. The take-up portion 7 has a take-up roller 71, and the take-up roller 71 is actively rotated by a rotary motor or the like, and a ribbon-shaped gel C is taken up on the outer periphery thereof. The outer diameter of the winding roller 71 is set appropriately according to the thickness H _C and the material of the gel C, it is set to a gel C is not cracked.

A take-up core 72 may be detachably attached to the outer circumference of the take-up roller 71, and a ribbon-shaped gel C may be taken up on the outer circumference of the take-up core 72. If the take-up core 72 is used, the roll-shaped gel C can be removed without losing its shape, and the handleability is good.

The outer circumference of the take-up roller 71 may be provided with irregularities. Due to the unevenness, slippage of the winding core 72 (however, gel C when there is no winding core 72) can be suppressed. Similarly, the outer circumference of the winding core 72 may be provided with irregularities. The unevenness can suppress the slip of the gel C.

The material of the take-up roller 71 is not particularly limited, but is, for example, metal or resin. The resin is excellent in light weight and excellent transportability. Non-slip rubber may be attached to the outer circumference of the take-up roller 71.

Similarly, the material of the winding core 72 is not particularly limited, but is, for example, metal or resin. The resin is excellent in light weight and excellent transportability. Non-slip rubber may be attached to the outer circumference of the take-up core 72.

(Gel manufacturing method)
FIG. 4 is a flowchart showing a method for producing a gel according to an embodiment. As shown in FIG. 4, the method for producing a gel includes molding (S1), solvent substitution (S2), drying (S3), and winding (S4). The molding unit 2 performs molding (S1), the solvent replacement unit 4 performs solvent substitution (S2), the drying unit 6 performs drying (S3), and the winding unit 7 performs winding (S4). To do.

The gel production method does not have to include all the treatments shown in FIG. 4, for example, when the solvent of the raw material liquid A is suitable for drying (S3), even if solvent substitution (S2) is not performed. Good. Further, the method for producing the gel may include a treatment different from the treatment shown in FIG. 4, for example, packaging may be included instead of winding (S4). In packing, the ribbon-shaped gel C is cut, and the cut gels are stacked in a packing container.

(Accommodation)
FIG. 5 is a cross-sectional view showing a second modification of the molded portion shown in FIG. As shown in FIG. 5, the molding unit 2 may further have an accommodating portion 21 accommodating the liquid layer B. If the transport sheet 11 floats on the liquid layer B, the density of the liquid layer B may be higher or lower than the density of the liquid layer B, but is preferably higher. The density of the raw material liquid A may be higher or lower than the density of the liquid layer B as long as the gel C can be formed on the transport sheet 11, but it is preferably low.

The transport sheet 11 slides on the liquid surface of the liquid layer B. The raw material liquid A is formed into a ribbon shape and gelled on the transport sheet 11 floating on the liquid layer B.

Since the liquid level of the liquid layer B naturally becomes horizontal due to gravity, the transport sheet 11 also becomes horizontal, and a flat and uniform gel C can be easily obtained by using the horizontal liquid level. Further, since the entire lower surface of the transport sheet 11 is horizontally supported, the area of the transport sheet 11 can be increased, and the area of the gel C can be increased. Further, since the transport sheet 11 prevents the liquid layer B from coming into contact with the raw material liquid A, the options for the combination of the liquid layer B and the raw material liquid A can be expanded. For example, even if the liquid layer B and the raw material liquid A are compatible with each other, since the transport sheet 11 exists between the liquid layer B and the raw material liquid A, the liquid layer B and the raw material liquid A are mixed. There is no such thing. Further, if water can be selected as the material of the liquid layer B, the cost can be reduced.

The liquid layer B preferably has a large density difference between the transport sheet 11 and the raw material liquid A so that the transport sheet 11 and the raw material liquid A layer can stably exist on the liquid layer B. The density difference is preferably 0.1 g / cm ³ or more, and more preferably 0.5 g / cm ³ or more. From the viewpoint of weight reduction, the density difference is preferably 3.0 g / cm ³ or less, and more preferably 2.0 g / cm ³ or less.

Further, as the liquid layer B, it is preferable to use a liquid layer B that does not deteriorate or swell the transport sheet 11 and does not react with each other so that the transport sheet 11 can stably exist on the liquid layer B.

The material of the liquid layer B is appropriately selected according to the transport sheet 11. Examples of the material of the liquid layer B include a liquid compound having a fluorine atom, a liquid compound having a chlorine atom, a liquid compound having a silicon atom, water, mercury and the like, and if there is a density difference from the raw material liquid A, fluorine. , Chlorine, bromine, or halogen atoms such as iodine, silicon atoms, etc. need not be contained. The water may contain water-soluble salts to adjust the density of the liquid layer B. Examples of the water-soluble salt include sodium chloride and the like.

Examples of the liquid compound having a fluorine atom include a fluorine-based solvent and a fluorine-based oil.

Fluorine-based solvents include hydrofluoroalkanes, chlorofluorocarbons, hydrochlorofluorocarbons, hydrofluoromonoethers, perfluoromonoethers, perfluoroalkanes, perfluoropolyethers, perfluoroamines, fluorine atom-containing alkanes, fluorine atom-containing aromatic compounds, and fluorine. Examples thereof include atom-containing ketones and fluorine atom-containing esters. Commercially available products of fluorine-based solvents include Asahi Clean AK-225 (CF ₃ CF ₂ CHCl ₂ ), AC-2000 (CF ₃ CF ₂ CF ₂ CF ₂ CF ₂ CHF ₂ ), AC-6000 (C F ₂ CF ₂ CHF ₂ ), which are registered trademarks of Asahi Glass Co., Ltd. CF ₃ CF ₂ CF ₂ CF ₂ CF ₂ CF ₂ CH ₂ CH ₃ ), AE-3000 (CF ₃ CH ₂ OCF ₂ CHF ₂ ); 3M company brand name Fluorinert and Novell 7100 (C ₄ F ₉ OCH ₃ ), _{_{_{_{7200 (C 4 F 9 OC 2}}}} H 5), 7300 (C 2 F 5 CF (OCH 3) CF (CF 3) 2); Du Pont-Mitsui Fluorochemicals Co., Ltd. trade name Vertrel _{_{_{XF (CF 3 CHFCHFC 2 F 5}}} ) , MCA, XH; Zeolora H (Heptafluorocyclopentane), which is a trade name of Nippon Zeon Co., Ltd., and the like.

Examples of commercially available fluorine-based oils include Solvay's brand name Fomblin and Daikin Industries' brand name Demnum and Daikin Industries.

Examples of the liquid compound having a chlorine atom include chlorine-based solvents and chlorine-based oils. Examples of the chlorine-based solvent include carbon tetrachloride, chloroform, methylene chloride and the like.

Examples of the liquid compound having a silicon atom include silicone oil and the like. Examples of the silicone oil include dimethyl silicone oil and methyl phenyl silicone oil. Examples of commercially available silicone oil products include KF-96, which is a trade name of Shin-Etsu Chemical Co., Ltd.

The molding unit 2 has a first heater 23, a second heater 24, and a third heater 25 in order to gel the raw material liquid A on the liquid layer B. The first heater 23 is arranged above the accommodating portion 21, the second heater 24 is arranged inside the liquid layer B, and the third heater 25 is arranged below the accommodating portion 21. The operation of these heaters is the same as in the first embodiment.

FIG. 6 is a plan view showing the accommodating portion shown in FIG. As shown in FIG. 6, the accommodating portion 21 is, for example, a rectangular container in a plan view, and has an upstream wall 211, a downstream wall 212, a pair of

side walls

213 and 214, and a bottom wall 215 (see FIG. 5). ..

The length L1 of the accommodating portion 21, that is, the length L1 from the upstream wall 211 to the downstream wall 212 is not particularly limited, but is, for example, 1 m to 100 m from the viewpoint of residence time and productivity. A length L1 of the housing portion 21 is constant, if the thickness H _C gel C is the same, as the progress of gelation of the raw material liquid A is high, and the retrieval speed of the feed rate and the gel C raw material liquid is greater Therefore, the production volume per unit time is improved.

The region from the upstream wall 211 to the downstream wall 212 can be distinguished in the transport direction of the raw material liquid A, for example, the first region A1, the second region A2, and the third region A3. The first region A1, the second region A2, and the third region A3 are arranged in this order from the upstream side to the downstream side.

The first region A1 is a region where gelation of the raw material liquid A starts, and is a region where cross-linking starts in a part of the raw material liquid A. The raw material liquid A is supplied onto the transport sheet 11 floating on the liquid layer B in the vicinity of the upstream wall 211 of the first region A1 and moves toward the downstream wall 212 together with the transport sheet 11. When cross-linking starts with a part of the raw material liquid A, the viscosity increases.

The second region A2 is a region in which gelation of the raw material liquid A progresses, cross-linking proceeds in the entire raw material liquid A, and a three-dimensional skeleton structure of a polymer is formed. At the downstream end of the second region A2, the viscous flow of the raw material liquid A is lost.

The third region A3 is a region in which the gelation of the raw material liquid A further progresses and a finer three-dimensional skeleton structure is formed. The third region A3 is a region where the gel C is aged. For example, when the gel raw material contains (1A) a silane compound and (1B) a catalyst, the third region A3 is a region where dehydration condensation is completed. The gel C is lifted from the liquid surface of the liquid layer B in the vicinity of the downstream wall 212 of the third region A3, and is taken out to the downstream side of the accommodating portion 21. The gel C may be slid out by an oblique plate-like body (not shown) provided on the downstream wall 212 of the accommodating portion 21 so that the gel C does not hit the downstream wall 212 of the accommodating portion 21. Since the gel C may be taken out from the accommodating portion 21, the taking-out portion 3 may be inside the accommodating portion 21 or may be outside the accommodating portion 21.

The first region A1, the second region A2, and the third region A3 may have the same temperature or different temperatures, but may be lower than the boiling point of the solvent in order to suppress boiling of the solvent. .. It is possible to prevent the three-dimensional skeleton structure of the polymer from being damaged by boiling the solvent.

The third region A3 may have a higher temperature than the first region A1 and the second region A2. Gelation can proceed slowly until most of the three-dimensional skeletal structure is formed, and then gelation can proceed rapidly. Therefore, the length L1 of the accommodating portion 21 can be shortened.

When the third region A3 has a higher temperature than the first region A1 and the second region A2, the temperature difference is, for example, 10 ° C to 50 ° C, preferably about 20 ° C.

The width W1 of the accommodating portion 21, that is, the width W1 of the pair of

side walls

213 and 214 is not particularly limited, but is, for example, 1 cm to 10 m.

(Support sheet)
FIG. 7 is a cross-sectional view showing a manufacturing apparatus according to a modified example. Hereinafter, the differences between the manufacturing apparatus 1 of the above embodiment and the manufacturing apparatus 1 of the present modification will be mainly described. The manufacturing apparatus 1 of this modification has a molding unit 2, a take-out unit 3, a solvent replacement unit 4, a relay unit 5, a drying unit 6, a winding unit 7, and a delivery unit 8. ..

The delivery unit 8 sends out the support sheet 100 toward the confluence of the ribbon-shaped gel C peeled off from the transport sheet 11 and the support sheet 100 that supports the ribbon-shaped gel C from below. After merging with the gel C, the support sheet 100 is continuously conveyed together with the gel C. Since the support sheet 100 supports the gel C from below during the transfer of the gel C, unintended deformation due to the weight of the gel C can be suppressed, and the gel C can be suppressed from cracking.

The support sheet 100 preferably merges with the gel C on the upstream side as much as possible so that the gel C can be protected for as long as possible, and may merge with the gel C between the accommodating portion 21 and the solvent replacement portion 4. For example, the support sheet 100 is curved along the outer circumference of the tension roller 31 below the gel C, then merges with the gel C, and then is sent out from the tension roller 31 to the downstream side. Since the distance between the gel C and the support sheet 100 is gradually shortened on the upstream side of the confluence point, air can be expelled and the biting of air bubbles can be suppressed.

The support sheet 100 may be sent to the winding unit 7 together with the gel C and wound in a roll together with the gel C so that the gel C can be protected for as long as possible. Since the gel C and the support sheet 100 are alternately laminated on the outer circumference of the take-up roller 71, it is possible to prevent the gel C from adhering to each other.

The support sheet 100 does not deteriorate or swell with the solvent of the gel C or the solvent of the solvent substitution, withstands the drying temperature of the gel C, and is slippery with respect to the gel C so as not to hinder the shrinkage and expansion of the gel C during drying. Anything is not particularly limited, but may be, for example, a resin sheet. In general, gel C shrinks once and then expands when it dries.

The support sheet 100 may be dense, but is preferably porous. Since the solvent can evaporate on both the upper and lower sides during drying, the drying can proceed evenly from both the upper and lower sides. It is also possible to proceed with solvent substitution evenly from both the upper and lower sides. As the porous support sheet 100, for example, a porous film of polyethylene terephthalate is used.

The support sheet 100 comes into contact with the gel C. Since the gel C has been solidified, even if the surface of the support sheet 100 is rough, the surface shape of the gel C is not transferred to the gel C.

The thickness of the support sheet 100 is, for example, 0.01 mm to 1 mm.

The width of the support sheet 100 may be narrower than the width of the gel C, but may be equal to or larger than the width of the gel C. If the width of the support sheet 100 is equal to or greater than the width of the gel C, the support sheet 100 can support the entire width direction of the gel C.

The delivery unit 8 has a delivery roller 81, and the delivery roller 81 rotates with the movement of the support sheet 100 pulled by the tension roller 31, and feeds out the support sheet 100 wound around the outer circumference.

A delivery core 82 may be detachably attached to the outer circumference of the delivery roller 81. If a plurality of delivery cores 82 are prepared, the support sheet 100 can be wound around another delivery core 82 while the support sheet 100 is fed out from one delivery core 82. Therefore, the roll-shaped support sheet 100 can be prepared in advance, and the waiting time can be shortened. Further, the support sheet 100 can be transported in a state of being wound around the delivery core 82, and the shape of the support sheet 100 can be prevented from being lost during transportation.

The outer circumference of the delivery roller 81 may be provided with irregularities. Due to the unevenness, slippage of the delivery core 82 (however, the support sheet 100 when the delivery core 82 is not provided) can be suppressed. Similarly, the outer circumference of the delivery core 82 may be provided with irregularities. The unevenness can suppress the slip of the support sheet 100.

The material of the delivery roller 81 is not particularly limited, but is, for example, metal or resin. The resin is excellent in light weight and excellent transportability. Non-slip rubber may be attached to the outer circumference of the delivery roller 81.

Similarly, the material of the delivery core 82 is not particularly limited, but is, for example, metal or resin. The resin is excellent in light weight and excellent transportability. Non-slip rubber may be attached to the outer circumference of the delivery core 82.

In this modification, the support sheet 100 merges with the gel C between the accommodating portion 21 and the solvent replacement portion 4, but merges with the gel C between the solvent replacement portion 4 and the drying portion 6. May be good. For example, the support sheet 100 may be curved along the outer circumference of the relay roller 51 below the gel C, subsequently merge with the gel C, and then sent out from the relay roller 51 to the downstream side. Since the distance between the gel C and the support sheet 100 is gradually shortened on the upstream side of the confluence point, air can be expelled and the biting of air bubbles can be suppressed.

The gel manufacturing method and the gel manufacturing apparatus according to the present disclosure have been described above, but the present disclosure is not limited to the above embodiment. Various changes, modifications, replacements, additions, deletions, and combinations are possible within the scope of the claims. These also naturally belong to the technical scope of the present disclosure.

This application claims priority based on Japanese Patent Application No. 2019-122347 filed with the Japan Patent Office on June 28, 2019, and the entire contents of Japanese Patent Application No. 2019-122347 are incorporated into this application. To do.

1 Manufacturing equipment 11 Conveying sheet 111 Flat part 112 Bank part 115 Surface modification part 12 Sheet supply part 13 Sheet peeling part 2 Molding part 21 Storage part 22 Raw material liquid supply part 3 Extraction part 4 Solvent replacement part 6 Drying part 7 Winding part A Raw material liquid B Liquid layer C Gel

Claims

The gel raw material liquid is continuously supplied from above to the moving flexible transport sheet,
The raw material liquid is formed into a ribbon shape and gelled on the transport sheet.
How to make a gel.
The transport sheet has a cross section orthogonal to the moving direction of the transport sheet, and is formed on a flat portion and an upper surface of the flat portion at intervals in a width direction orthogonal to the moving direction of the transport sheet. The method according to claim 1, which has a bank portion.
The transport sheet has a cross section orthogonal to the moving direction of the transport sheet, and is formed on a flat portion and an upper surface of the flat portion at intervals in a width direction orthogonal to the moving direction of the transport sheet. The method according to claim 1, further comprising a surface modification portion having a surface tension smaller than that of the flat portion.
Claims 1 to 1, wherein the transport sheet is bent at a position downstream of the position where the raw material liquid is supplied in the transport direction of the raw material liquid, and the transport sheet is continuously peeled off from the ribbon-shaped gel. The method according to any one of 3.
Further, the ribbon-shaped gel continuously peeled from the transport sheet and the support sheet that supports the ribbon-shaped gel from below are merged, and the ribbon-shaped gel and the support sheet are continuously connected. The method according to claim 4, wherein the product is transported.
Further, any one of claims 1 to 5, wherein the solvent contained inside the ribbon-shaped gel is replaced with another solvent while the ribbon-shaped gel passes through the enclosed region. The method described in.
The method according to any one of claims 1 to 6, further comprising removing the solvent contained inside the ribbon-shaped gel while passing through the enclosed region of the ribbon-shaped gel. ..
The method according to claim 7, wherein the ribbon-shaped gel that has passed through the region from which the solvent is removed is wound into a roll.
The method according to any one of claims 1 to 8, wherein the transport sheet is floated on a liquid layer, and the raw material liquid is formed into a ribbon shape and gelled on the transport sheet floated on the liquid layer. Method.
A flexible transfer sheet that supports and moves the gel raw material liquid from below,
A raw material liquid supply unit that continuously supplies the raw material liquid from above to the transport sheet,
A gel manufacturing device having.
The transport sheet has a cross section orthogonal to the moving direction of the transport sheet, and is formed on a flat portion and an upper surface of the flat portion at intervals in a width direction orthogonal to the moving direction of the transport sheet. The device according to claim 10, further comprising a bank portion.
The transport sheet has a cross section orthogonal to the moving direction of the transport sheet, and is formed on a flat portion and an upper surface of the flat portion at intervals in a width direction orthogonal to the moving direction of the transport sheet. The apparatus according to claim 10, further comprising a surface modification portion having a surface tension smaller than that of the flat portion.
Further, the claim has a sheet peeling portion for continuously peeling the transport sheet from the ribbon-shaped gel obtained by gelling the raw material liquid at a position downstream of the raw material liquid supply unit in the transport direction of the raw material liquid. The apparatus according to any one of 10 to 12.
The device according to claim 13, wherein the transport sheet is an endless belt circulated between the sheet peeling section and the raw material liquid supply section.
Further, a claim having a delivery unit that feeds out the support sheet toward a confluence point between the ribbon-shaped gel continuously peeled from the transport sheet and the support sheet that supports the ribbon-shaped gel from below. Item 13. The apparatus according to item 13.
The apparatus according to any one of claims 10 to 15, further comprising a winding portion for winding a ribbon-shaped gel obtained by gelling the raw material liquid into a roll shape.
The device according to any one of claims 10 to 16, further comprising an accommodating portion for accommodating a liquid layer that floats the transport sheet.