Sheet manufacturing method, sheet manufacturing apparatus, and sheet

Abstract

A sheet is stably manufactured even when a liquid material having a low viscosity is used. This sheet manufacturing method comprises: a step (a) in which a liquid material (LM) that contains a starting material and has a viscosity of 100,000 mPa * s or less is adjusted; (b) a step for forming a coated body by applying the liquid material (LM) in the form of a sheet by means of a coater (13); (c) a step in which the coated body is cured to produce a sheet (50); and (d) a step in which the sheet (50) is wound.

Description

TECHNICAL FIELD

[0001] The present application relates to a sheet manufacturing method, a sheet manufacturing apparatus, and a sheet. BACKGROUND

[0002] As a sheet manufacturing method, a method of melting a raw material using an extruder, and extruding the obtained molten resin in a sheet shape from an extrusion molding die (T-die) to manufacture the sheet is known (for example, see Patent Literature 1 (Japanese Patent Application Publication No. 2020-146853)).

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent Application Publication No. 2020-146853 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] However, the extruded molten resin is provided with a prescribed distance (air gap) from the extrusion molding die (T-die) to the cooling roll, and therefore, in the air gap, a phenomenon of so-called neck-in, in which the manufactured film width is narrower than the die width, occurs due to the weight, tension, speed, and the like of the molten resin.

[0008] At this time, in the case where the viscosity of the molten resin is low, there is a tendency for the neck-in amount to increase, and sometimes it is difficult to manufacture a sheet of a desired shape.

[0009] Thus, an object of the present application is to provide a sheet manufacturing method and a sheet manufacturing apparatus that enable a sheet of a desired shape to be manufactured even in the case where the viscosity of a liquid material containing a raw material is low when manufacturing a sheet containing a resin material.

[0010] Other problems and novel features will be apparent from the description and drawings of the present specification.

[0011] MEANS FOR SOLVING THE PROBLEMS

[0012] The sheet manufacturing method of one embodiment has the following steps: (a) a step of adjusting a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less; (b) a step of forming a coated body by coating the liquid material in a sheet shape using a coater; (c) a step of curing the coated body to manufacture a sheet; and (d) a step of winding up the sheet.

[0013] The manufacturing apparatus of the sheet as one embodiment has: a raw material container that adjusts and stores a liquid material containing a raw material and having a prescribed viscosity; an applicator that applies the liquid material; a solidification area that solidifies the applied material to become a sheet; and a sheet winding section that winds the sheet.

[0014] In the manufacturing method of the sheet and the manufacturing apparatus of the sheet described above, the adjustment of the liquid material is such that the viscosity thereof is 100,000 mPa s or less.

[0015] Effects of the Invention

[0016] According to one embodiment, in the manufacturing of the sheet, even in the case of using a liquid material of a viscosity in which the amount of necking becomes large when a mold for extrusion molding (T-die) is used, the sheet can be stably manufactured. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a view showing the schematic configuration of a manufacturing apparatus of a sheet of Embodiment 1.

[0018] Figure 2 is a view explaining the case in which a gravure roll is applied as the applicator in Figure 1 .

[0019] Figure 3 is a view showing the schematic configuration of a manufacturing apparatus of a sheet of Embodiment 2.

[0020] Figure 4 is a view showing the schematic configuration of a manufacturing apparatus of a sheet of Embodiment 3.

[0021] Figure 5 is a view showing a modification example of the manufacturing apparatus of a sheet of Figure 4 .

[0022] Figure 6 is a view showing the chemical structural formula of glucomannan.

[0023] Figure 7 is a view showing the chemical structural formula of cellulose.

[0024] Figure 8 is a view showing the schematic configuration of a moisture recovery apparatus using a nonwoven fabric sheet.

[0025] Figure 9 is a view showing the schematic configuration of a moisture recovery apparatus using a nonwoven fabric sheet. DETAILED DESCRIPTION

[0026] Hereinafter, the present embodiment will be explained in detail with reference to the drawings. Note that in all the drawings used to explain the embodiments, the same reference signs are attached to the components having the same functions, and repeated explanation thereof will be omitted.

[0027] (Embodiment 1)

[0028] <Manufacturing device of sheet>

[0029] Figure 1 is a view schematically showing the configuration of a manufacturing device of a sheet of the present embodiment.

[0030] This Figure 1 The manufacturing device 10 of a sheet shown in Fig. 1 has a raw material container 11 that adjusts and stores a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less, a base material carrying-out section 12 that carries out a base material BM, an applicator 13 that applies the liquid material to the base material BM carried out from the base material carrying-out section 12, a solidification region 14 that solidifies the liquid material applied to the base material BM to become a sheet, a peeling member 15 that peels the sheet 50 from the base material BM at a rear stage of the solidification region 14, and a sheet winding section 16 that winds the sheet 50 peeled from the base material BM. Further, there is a base material winding section 17 that winds the base material BM after the sheet is peeled.

[0031] The raw material container 11 is a container that adjusts and stores a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less. The liquid material stored in the raw material container 11 can also be said to be an application liquid applied to the base material BM by the applicator 13 described later.

[0032] In the raw material container 11, a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less is adjusted. For example, in a case where the above-described viscosity is satisfied by melting the raw material by heating, it is possible to store only the raw material in the raw material container 11. In this case, as the viscosity adjustment, there is only a heating section that heats the raw material to become the above-described viscosity. As the heating section, for example, a heating source such as a heater can be cited, and it is sufficient that the raw material is heated by the heating source and the temperature is maintained in the raw material container 11.

[0033] In addition, it is also possible to mix the raw material with a solvent and adjust to a liquid material having a viscosity of 100,000 mPa-s or less. For example, in a case where it is necessary to heat to a very high temperature in order to melt the raw material by heating in the above-described manner, or even if the viscosity is difficult to become 100,000 mPa-s even if it is melted by heating, etc., it is possible to use a solvent to dissolve the raw material and adjust the viscosity to 100,000 mPa-s or less. In addition, even if the raw material becomes 100,000 mPa-s or less by heating and melting, it is possible to adjust the viscosity using a solvent.

[0034] In this way, in the case where the raw material is mixed with the solvent to become a raw material solution, for example, a solvent supply portion for supplying the solvent is provided in the raw material container 11, and the amount of the supplied solvent is adjusted so that the raw material solution (liquid material) becomes the above-mentioned viscosity range.

[0035] Note that, here, the viscosity of the liquid material is the viscosity of the coating liquid for coating by the coater 13, and is preferably 10 to 80,000 mPa-s, and more preferably 100 to 10,000 mPa-s.

[0036] The substrate carrying-out portion 12 is a portion configured to send out the substrate BM. Here, the substrate BM is a substrate for coating the above-mentioned liquid material. In the substrate carrying-out portion, the substrate BM is wound in a roll shape, and it is possible to continuously send out the substrate BM to the coater 13 and coat the liquid material on the surface thereof.

[0037] The coater 13 is a device that coats the liquid material sent from the raw material container 11 with a pump or the like on the substrate BM. The coater 13 can use a publicly known coater used in sheet formation, and for example, a coater of a mode that performs contact coating processing such as a die coater, a gravure coater, a rod coater, and the like can be cited. It is possible to coat the liquid material on the substrate BM with a uniform width by the coater 13. These coaters can be selected, for example, in accordance with the viscosity of the liquid material.

[0038] As the coater 13, in Figure 1 a die coater is exemplified. In this case, a die coater of a slot die mode that coats the liquid material on the substrate BM while extruding it from a die is preferable. At this time, a back roll 18 is provided at a position opposite to a slit that extrudes the liquid material from the coater 13 with the substrate interposed therebetween.

[0039] In addition, as the coater 13, in Figure 2 a gravure coater is exemplified. Figure 2 is a view that explains the configuration of the coater 13 that coats the liquid material LM on the substrate BM in the sheet manufacturing device 10. Here, the gravure coater is shown in a cross-sectional configuration in order to understand the internal configuration.

[0040] The Figure 2 gravure coater shown in FIG. 13 is a longitudinal coater, and a chamber (tank) 13a is arranged in the vertical direction (a direction parallel to the direction of gravity). The coater has: the chamber (tank) 13a for storing the liquid material LM; a roll (gravure roll) CR that enters a portion of the chamber (tank) 13a for coating; a doctor 13b for preventing splashing of the liquid material LM and adjusting the amount of liquid on the roll surface; and a second doctor 13c for preventing leakage of the coating liquid from the gap between the liquid material in the chamber (tank) and the roll (gravure roll) CR.

[0041] The first doctor blade 13b is disposed on the side of the rotation direction of the coating roller CR in a manner that the angle and the pressing force of the first doctor blade 13b can be adjusted, so as to adjust the liquid amount of the liquid material LM adhered to the surface of the coating roller CR. Further, the liquid material SLM in a sheet shape is formed by the liquid material LM adhered to the surface of the coating roller CR being transferred to the surface of the substrate BM.

[0042] Note that the chamber (tank) 13a of the gravure coater can be either longitudinal or transverse, and in the case of the transverse type, the second doctor blade 13c for preventing leakage of the coating liquid is not required, and the first doctor blade 13b for preventing splashing of the liquid material LM and adjusting the liquid amount on the roller surface can be provided.

[0043] The curing area 14 is an area in which the liquid material in a sheet shape coated on the substrate BM is cured to a sheet material. In this curing area 14, in the case where the liquid material contains only a raw material, the temperature of the liquid material in a sheet shape coated on the substrate BM is lowered to cure it. At this time, for example, a cooling mechanism does not need to be provided in particular, and the temperature of the liquid material in a sheet shape can be naturally lowered to cure it at normal temperature or the like of about 25°C. Alternatively, a cooling mechanism can be provided, and the temperature of the liquid material in a sheet shape can be actively lowered to cure it.

[0044] Further, in the case where the liquid material is a raw material solution obtained by mixing a raw material with a solvent, the solvent is volatilized from the liquid material in a sheet shape coated on the substrate BM by heating or the like to cure it. At this time, a heating mechanism does not need to be provided in particular, and the solvent can be naturally volatilized to cure it at normal temperature or the like. Alternatively, a heating mechanism such as a heater can be provided, and the temperature of the liquid material in a sheet shape can be actively heated to promote volatilization of the solvent to cure it.

[0045] The peeling member 15 is disposed at the rear stage of the above-described curing area 14, and is a member for peeling the sheet material 50 obtained by curing in the curing area 14 from the substrate BM. As the peeling member 15, it is only necessary to separate the sheet material 50 from the substrate BM, and a publicly known peeling member can be used. As the peeling member 15, for example, a doctor blade or the like in which a front end portion thereof is provided as an acute angle, is inserted between the substrate BM and the sheet material 50, and can peel the sheet material 50 from the substrate BM can be cited.

[0046] The sheet material winding portion 16 is a member that winds the sheet material 50 peeled from the substrate BM by the peeling member 15, and can accommodate it as a wound sheet material. Here, the wound sheet material 50 can be a product as a wound sheet material. Alternatively, the sheet material can be further processed as necessary to be a sheet material product.

[0047] The substrate take-up section 17 is a section that takes up the substrate BM after the sheet 50 is peeled by the peeling section 15 and can accommodate it as a roll-shaped substrate. Here, the taken-up substrate BM can be used again as the substrate BM for the manufacture of the sheet 50. At this time, as needed, it is particularly preferable to clean or the like the surface after the sheet 50 is formed so that the raw material does not remain.

[0048] In addition, it is preferable to provide a feed roller 19 between the substrate carrying-out section 12 and the substrate take-up section 17 so that the substrate BM can be stably fed out. This feed roller 19 has a function of feeding the substrate BM (the substrate BM on which the coated body or the sheet 50 is formed after the liquid material is coated) to the rear section. In addition, at this time, pressure can be applied so that the coated body or the sheet 50 is tightly attached to the substrate BM.

[0049] <Method for manufacturing sheet>

[0050] Next, the method for manufacturing the sheet in Embodiment 1 will be described. In the method for manufacturing the sheet, the following processes are included: a process of adjusting a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less ((a) process); a process of forming the liquid material into a sheet shape after the (a) process ((b) process); a process of solidifying the liquid material formed into a sheet shape to produce a sheet ((c) process) after the (b) process; and a process of taking up the sheet ((d) process) after the (c) process.

[0051] Hereinafter, as a specific device configuration, the method for manufacturing a sheet using the sheet manufacturing device 10 described in Embodiment 1 will be described. Figure 1

[0052] First, the process of adjusting a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less ((a) process) is performed.

[0053] In this process of adjusting the viscosity, as described above, in the raw material container 11, a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less is adjusted. For example, in a case where the above-described viscosity is satisfied by melting the raw material by heating, only the raw material is stored in the raw material container 11, and the raw material is heated to become the above-described viscosity to adjust the viscosity.

[0054] In addition, in a case where the raw material is mixed with a solvent and the viscosity thereof is adjusted to 100,000 mPa-s or less, the amount of the solvent to be supplied is adjusted so that the raw material solution (liquid material) obtained by mixing the solvent in the raw material becomes the above-described viscosity range. In this case, temperature adjustment such as heating can also be combined as needed.

[0055] ​The viscosity of the liquid material in the (a) process is, as described above, the viscosity of the coating liquid for coating by the coater 13, and is preferably 10 to 80,000 mPa-s, and more preferably 100 to 10,000 mPa-s.

[0056] Next, after the (a) process, a process of coating the liquid material in a sheet shape by a coater ((b) process) is performed.

[0057] In the present embodiment, the substrate carrying-out section 12 is provided, and the liquid material is coated in a sheet shape by the coater 13 on the substrate BM carried out from the substrate carrying-out section 12, whereby a sheet-shaped liquid material SLM (coated body) is produced.

[0058] The substrate BM used here is preferably a release substrate. The substrate BM is, for example, preferably a substrate including a resin material such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), or the like.

[0059] In addition, in order to easily peel the sheet 50 from the substrate BM, a release agent layer can also be provided on the surface of the substrate BM. As the release agent used at this time, a publicly known release agent can be used, and for example, a silicone-based release agent, a non-silicone-based release agent, or the like can be mentioned.

[0060] In addition, it is also preferable that the substrate BM be subjected to a treatment of increasing the surface tension by corona discharge or the like before the coating of the next liquid material. In the case where such a treatment is performed, it is preferable to perform a corona discharge treatment, and for example, in the case of polyethylene terephthalate (PET), the surface tension is made to be in the range of 50 to 70 dyn / cm, and in the case of polyphenylene sulfide (PPS), the surface tension is made to be in the range of 60 to 80 dyn / cm.

[0061] At this time, the coating amount of the liquid material LM is adjusted in correspondence with the thickness of the sheet 50 finally formed, and the thickness of the sheet-shaped liquid material SLM is determined. That is, in the case where the liquid material LM includes only a raw material, the thickness of the sheet-shaped liquid material SLM immediately after coating does not greatly change to become the sheet 50, and thus can be coated to the same thickness as the target thickness. In addition, in the case where a raw material solution obtained by mixing a raw material and a solvent is the liquid material LM, the thickness of the sheet-shaped liquid material SLM immediately after coating changes from the sheet 50 produced. This is because, in the process of forming the sheet 50, the solvent is volatilized, and the raw material solution (liquid material) is coated in consideration of the amount of volatilization so that the sheet 50 becomes the target thickness.

[0062] In the coating of the liquid material LM, the thickness of the sheet-shaped liquid material SLM to be coated varies for various reasons such as the conveyance speed of the substrate, the viscosity of the liquid material LM used, the amount of the liquid material LM ejected in the coater 13, and the like, and thus the coating conditions are adjusted to be the above-mentioned target thickness.

[0063] The viscosity of the liquid material LM is set to be 100,000 mPa-s or less as described above. The conveyance speed of the substrate BM is preferably, for example, 1 to 500 m / min, more preferably 5 to 300 m / min.

[0064] Note that the coater 13 is preferably selected in accordance with the viscosity of the liquid material LM. For example, in the case where the viscosity of the liquid material LM is 1,000 mPa-s or more, a die coater is preferably used as the coater 13, and in the case where the viscosity of the liquid material LM is less than 1,000 mPa-s, a gravure coater is preferably used as the coater 13. In addition, in the case where the viscosity of the liquid material LM is 10,000 mPa-s or more, a device having a screw shape such as a single-screw extruder, a twin-screw extruder, or the like is preferably used instead of a pump.

[0065] Further, after the (b) step, a step of curing the liquid material molded into a sheet to produce the sheet 50 is performed ((c) step).

[0066] In the present embodiment, the liquid material coated on the substrate BM is cured to produce a sheet in which the substrate BM and the sheet 50 are laminated. Here, the curing of the liquid material is performed in the curing region 14.

[0067] In the case where the liquid material contains only a raw material, the temperature of the sheet-shaped raw material coated on the substrate BM is lowered to cure it. At this time, for example, a cooling mechanism does not need to be provided in particular, and the temperature of the sheet-shaped raw material can be naturally lowered to cure it at normal temperature or the like. Alternatively, a cooling mechanism can be provided, and the temperature of the sheet-shaped raw material can be actively lowered to cure it.

[0068] The temperature at which the sheet-shaped raw material is cured at this time is a temperature inherent to the raw material used, and is a temperature lower than the melting point or the glass transition temperature of the raw material. By setting the temperature to be such a temperature, the raw material in a liquid state is cured to produce a sheet.

[0069] In the case where the liquid material is a raw material solution in which a raw material and a solvent are mixed, the solvent is volatilized from the sheet-shaped liquid material coated on the substrate BM by heating or the like to cure it. At this time, the volatilization of the solvent can be naturally performed at normal temperature or the like, but in order to improve the production efficiency, it is preferable to provide a heating mechanism such as a heater to heat the sheet-shaped liquid material, promote the volatilization of the solvent, and cure it. In this way, the sheet 50 can be formed.

[0070] At this time, in the sheet manufacturing apparatus 10 of the embodiment, the sheet 50 is manufactured by layering the sheet 50 on the base material BM, and the sheet 50 can be peeled from the base material BM using a peeling member 15 such as a doctor blade. By this peeling operation, the sheet 50 physically independent from the base material BM is manufactured. Figure 1

[0071] Then, after this peeling, a process of winding the sheet 50 ((d) process) is performed. Here, the sheet 50 peeled from the base material BM is wound in a roll shape by a sheet winding section 16. In this way, the sheet as a product can be continuously manufactured.

[0072] In addition, at the same time as the winding of the sheet, the base material BM after the peeling of the sheet is wound in a roll shape by a base material winding section 17. Here, the wound base material BM can be used again as the base material BM for the manufacture of the sheet 50. At this time, as necessary, it is particularly preferable to clean the surface on which the sheet 50 was formed or the like so as not to leave the raw material.

[0073] By being configured as the above embodiment, even in the case where a liquid material having a low viscosity is used as the raw material, a sheet largely different from the desired shape such as necking can be suppressed, the restriction of the usable raw material can be greatly relaxed, and a sheet manufacturing technique having a wide range of applications can be provided.

[0074] (Embodiment 2)

[0075] <Sheet Manufacturing Apparatus>

[0076] Figure 3 is a view schematically showing the configuration of a sheet manufacturing apparatus of another embodiment.

[0077] This Figure 3 The sheet manufacturing apparatus 20 shown in FIG. 8 is similar to the sheet manufacturing apparatus 10 described above, and has a raw material container 11 that adjusts and stores a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less, a base material carrying-out section 12 that carries out the base material BM, a coater 13 that coats the liquid material on the base material BM carried out from the base material carrying-out section 12, a solidification section 14 that solidifies the liquid material coated on the base material BM into a sheet, a peeling member 15 that peels the sheet 50 from the base material BM at a rear stage of the solidification section 14, and a sheet winding section 16 that winds the sheet 50 peeled from the base material BM. In addition, the sheet manufacturing apparatus 20 has a base material winding section 17 that winds the base material BM after the peeling of the sheet.

[0078] Further, the sheet manufacturing apparatus 20 has a drying treatment section 21, which is different from the sheet manufacturing apparatus 10. Hereinafter, the description of the same configuration will be omitted, and the different configuration will be described in detail.

[0079] ​This sheet material manufacturing apparatus 20, as described above, includes a drying unit 21 in addition to the configuration of the sheet material manufacturing apparatus 10. The drying unit 21 is located in the curing area 14 and is a component that dries the solvent contained in the liquid material formed into a sheet on the substrate BM. Specifically, this second embodiment uses a raw material solution (liquid material) that is a mixture of a raw material and a solvent as the liquid material.

[0080] The drying process section 21 is provided to efficiently volatilize the solvent contained in the liquid material sprayed onto the substrate BM in step (c). Typically, a heated atmosphere is created within the drying process section 21 to promote solvent volatilization. To create a heated atmosphere, for example, a gas (such as air) heated to a set temperature by a heat source such as a heater can be introduced into the drying process section 21. In this case, it is preferable to continuously introduce the heated gas so that the temperature within the drying process section 21 can be maintained near the set temperature.

[0081] The optimal heating temperature can be set depending on the solvent used. For example, when using water or a lower alcohol as the solvent, the heating temperature is preferably between 50°C and 90°C. However, the upper limit is set below the boiling point of the solvent. This temperature range can intentionally improve the solvent's volatilization efficiency and prevent the formation of bubbles within the sheet due to boiling of the solvent. Furthermore, to promote volatilization and drying, a blower capable of blowing air toward the sheet-like liquid material may be provided.

[0082] Furthermore, if a drying unit 21 is provided, a solvent recovery mechanism may be provided to cool and liquefy the volatilized solvent generated within the drying unit 21 and then recover it. This solvent recovery mechanism allows the solvent to be reused. Furthermore, the recovered solvent can be recycled and reused as a solvent for dissolving raw materials. This reuse allows for cost reduction and efficient sheet material production in the sheet material manufacturing process of this embodiment.

[0083] <Method for producing sheet>

[0084] In this embodiment, the sheet manufacturing apparatus 20 used differs from the sheet manufacturing apparatus 10 in terms of whether or not it includes the drying process section 21, as described above. Therefore, the basic operation in the sheet manufacturing method is the same as that in the first embodiment.

[0085] In this second embodiment, in addition to the operation in the first embodiment, the liquid material applied to the base material BM is heated by the drying unit 21 to volatilize the solvent contained in the liquid material and dry it, thereby efficiently converting the sheet-like liquid material SLM into a sheet 50. This drying process is performed in the curing area 14.

[0086] The drying process is preferably heated to a temperature that promotes volatilization of the solvent used, and the optimum temperature is set according to the solvent used. As the heating temperature, for example, in the case where water, a lower alcohol is used as the solvent, 50 to 90°C is preferable. However, the upper limit is set to a temperature lower than the boiling point of the solvent. By setting to such a temperature range, it is possible to intentionally increase the volatilization efficiency of the solvent, and it is possible to avoid the occurrence of bubbles in the sheet due to boiling of the solvent. In addition, in order to promote volatilization and drying, it is also possible to be configured to be provided with a blower that can blow air to the sheet-shaped liquid material SLM.

[0087] In addition, a solvent recovery mechanism can be provided in the above-described manner to cool and liquefy the solvent volatilized in the drying process section 21 to recover the solvent. The solvent thus recovered can be recycled as the raw material solvent.

[0088] (Embodiment 3)

[0089] <Sheet manufacturing apparatus>

[0090] Figure 4 is a view schematically showing the configuration of the sheet manufacturing apparatus of the present embodiment.

[0091] The Figure 4 The sheet manufacturing apparatus 30 shown in FIG. 1 has a raw material container 11 that adjusts and stores a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less, a heating roller 31 (31a, 31b, 31c), an applicator 13 that applies the liquid material to the heating roller 31 (31a), a curing area 32 that cures the liquid material applied to the heating roller 31 (31a) to become a sheet, a peeling member 33 that peels the sheet 50 from the heating roller 31 (31c), and a sheet winding section 16 that winds the sheet 50 peeled from the heating roller 31 (31c).

[0092] The raw material container 11, the applicator 13, the sheet winding section 16, and the feed roller 19 of the sheet manufacturing apparatus 30 can be configured the same as in Embodiment 1, and the description thereof is omitted. In addition, the sheet manufacturing apparatus 30 does not have a base material carrying-out section 12, a peeling member 15 that peels the sheet 50 from the base material, and a base material winding section 17 because it does not use a base material.

[0093] In the present embodiment, unlike Embodiment 1, the heating roller 31 is provided. Furthermore, it is configured to apply the liquid material directly to the heating roller 31 (31a) using the applicator 13. The heating roller 31 is a member that is heated to a temperature that promotes volatilization of the solvent contained in the raw material solution (liquid material) applied from the applicator 13 and cures it.

[0094] The heating roller 31 can also be provided in plural. By providing the heating roller 31 in plural, it is possible to ensure the time for volatilizing and drying the solvent from the coated liquid material, and it is possible to further promote the degree of solidification. In Figure 4 In the present embodiment, an example is shown in which three heating rollers 31a, 31b, 31c are provided as the heating roller 31.

[0095] The solidification region 32 is provided in the sheet manufacturing apparatus 30 between the portion at which the raw material solution (liquid material) is coated from the coater 13 to the heating roller 31 and the portion at which the sheet is wound. In the solidification region 32, the portion in which the solvent is mainly volatilized and dried and solidified is the region in which the heating roller 31 is provided.

[0096] The peeling member 33 is a member that peels the sheet from which the solvent has been volatilized (also including the sheet in the middle of drying) from the heating roller 31 (31c). Thereby, only the sheet is separated, and then the sheet is carried by the feed roller 19 and manufactured as the sheet 50 that is the final product, and is wound in a roll shape by the sheet winding portion 16.

[0097] <Sheet manufacturing method>

[0098] Next, the sheet manufacturing method in Embodiment 3 will be described. In the sheet manufacturing method, as in Embodiment 1, the following processes are provided: a process of adjusting a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less ((a) process); a process of forming the liquid material into a sheet shape after the (a) process ((b) process); a process of solidifying the liquid material formed into a sheet shape to produce a sheet ((c) process); and a process of winding the sheet after the (c) process ((d) process).

[0099] Hereinafter, as a specific apparatus configuration, the sheet manufacturing method using the sheet manufacturing apparatus 30 described in Embodiment 1 will be described. Figure 4 Hereinafter, as a specific apparatus configuration, the sheet manufacturing method using the sheet manufacturing apparatus 30 described in Embodiment 1 will be described.

[0100] First, the process of adjusting a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less ((a) process) is performed.

[0101] The process of adjusting the viscosity is performed as described above, and a liquid material containing a raw material and having a viscosity of 100,000 mPa-s or less is adjusted in the raw material container 11. For example, in a case where the raw material is mixed with a solvent and the viscosity thereof is adjusted to 100,000 mPa-s or less, adjustment of the amount of the solvent to be supplied is performed so that the raw material solution (liquid material) obtained by mixing the solvent with the raw material becomes in the above-described viscosity range.

[0102] Here, the viscosity of the raw material solution is the viscosity of the coating liquid for coating by the coater 13, and is preferably 10 to 80,000 mPa-s, more preferably 100 to 10,000 mPa-s.

[0103] Next, after the (a) step, a step of molding the liquid material into a sheet shape is performed ((b) step).

[0104] In the present embodiment, a heating roller 31 is provided, and the liquid material is molded into a sheet shape by coating the liquid material onto the heating roller 31 using the coater 13.

[0105] At this time, the thickness of the sheet-shaped liquid material SLM is determined by adjusting the coating amount of the liquid material corresponding to the thickness of the finally formed sheet 50. That is, in the case of the raw material solution in which the raw material is mixed with a solvent, the thickness of the sheet-shaped liquid material SLM immediately after coating is different from the thickness of the manufactured sheet 50. This is because the solvent is volatilized in the process of forming the sheet 50, and the raw material solution (liquid material) is coated taking into account the amount of volatilization so that the sheet 50 becomes the target thickness.

[0106] In the coating of the liquid material, the thickness of the coated sheet-shaped liquid material SLM varies due to various reasons such as the conveyance speed (rotation speed) of the heating roller 31, the viscosity of the liquid material used, the amount of liquid material ejected from the coater 13, and the like, and thus the coating conditions are adjusted to become the above-described target thickness.

[0107] The viscosity of the liquid material is set to 100,000 mPa-s or less as described above. The conveyance speed of the heating roller 31 is, for example, preferably 1 to 500 m / min, more preferably 5 to 300 m / min.

[0108] Further, after the (b) step, a step of solidifying the liquid material molded into a sheet shape to manufacture the sheet 50 is performed ((c) step).

[0109] In the present embodiment, the sheet 50 is manufactured by solidifying the liquid material coated on the heating roller 31. Here, the solidification of the liquid material is performed in a solidification region 32.

[0110] In the case where the liquid material is a raw material solution in which a raw material is mixed with a solvent, the solvent is volatilized from the sheet-shaped liquid material SLM coated on the heating roller 31 by heating or the like to solidify the same. At this time, in order to promote the volatilization of the solvent, a heating mechanism such as a heater is provided inside the roller, and the sheet-shaped liquid material SLM is heated to promote the volatilization of the solvent and solidify the same.

[0111] In Figure 4In this embodiment, as the heating roller 31, three heating rollers 31a, 31b, and 31c are provided, and first, the sheet-shaped liquid material SLM is ejected from the coater 13 to the heating roller 31a, and the liquid material is heated by directly contacting the heating roller 31a. Thus, the configuration is such that the solvent contained in the liquid material immediately after being ejected is actively volatilized.

[0112] The sheet-shaped liquid material SLM passes through the heating roller 31b and the heating roller 31c in this order from the heating roller 31a, and is dried by volatilizing the solvent using each heating roller while becoming a sheet. By passing through a plurality of heating rollers 31 like this, the drying time can be ensured.

[0113] As the heating temperature in the heating roller 31, the optimum temperature can be set in correspondence with the solvent used, and for example, in the case where water or a lower alcohol is used as the solvent, 50 to 90°C is preferable. However, the upper limit value is set to a temperature lower than the boiling point of the solvent. By setting to such a temperature range, the volatilization efficiency of the solvent can be intentionally increased, and the occurrence of bubbles in the sheet due to boiling of the solvent can be avoided. In addition, in order to promote volatilization and drying, a configuration in which a blower that blows air to the sheet-shaped liquid material SLM can be provided.

[0114] At this time, in the sheet manufacturing apparatus 30, Figure 4 In the sheet manufacturing apparatus 30, the sheet 50 after being cured is provided on the heating roller 31 (31c), and the sheet 50 can be peeled from the heating roller 31 (31c) using a peeling member 33 such as a doctor blade. By this peeling operation, the sheet 50 can be provided physically independent of the heating roller 31 (31c).

[0115] Further, after this peeling, the sheet 50 is carried by the feeding roller 19, and then a process of winding the sheet 50 ((d) process) is performed. Here, the sheet 50 is wound into a roll shape by the sheet winding unit 16. In this way, the sheet as a product can be continuously manufactured.

[0116] By providing the configuration of the above embodiment, even in the case where a liquid material having a low viscosity is used as a raw material, a sheet largely different from the desired shape such as necking can be suppressed, the restriction on the raw material that can be used can be greatly relaxed, and a sheet manufacturing technique with a wide range of applications can be provided.

[0117] [Modified example]

[0118] <Sheet manufacturing apparatus>

[0119] In Embodiment 3, it can be provided that Figure 5The sheet manufacturing apparatus 40 is configured as shown. The sheet manufacturing apparatus 40 has the same configuration as the sheet manufacturing apparatus 30, and further has a drying treatment section 41 in which the heating roller 31 is disposed, and a drying treatment section 42 disposed at a position at which the sheet is carried by the feeding roller 19. That is, the sheet manufacturing apparatus 40 differs from the sheet manufacturing apparatus 30 in that the drying treatment sections 41 and 42 are additionally provided.

[0120] The drying treatment section 41 is disposed in the curing region 32, and is a member in which the heating roller 31 is disposed. The drying treatment section 41 has a function of efficiently volatilizing and drying the solvent contained in the liquid material applied to the heating roller 31.

[0121] It is preferable that the drying treatment section 41 heat the temperature inside thereof to a temperature at which volatilization of the solvent is promoted. The temperature can be the same as the temperature described with respect to the heating roller 31 described above, and can be appropriately adjusted in correspondence with the solvent used. For example, in the case in which water or a lower alcohol is used as the solvent, 50 to 90°C is preferable. However, the upper limit value is set to a temperature lower than the boiling point of the solvent. By setting to such a temperature range, it is possible to intentionally increase the volatilization efficiency of the solvent, and it is possible to avoid the generation of bubbles in the sheet due to boiling of the solvent. In addition, in order to promote volatilization and drying, it is also possible to be configured to have a blower that blows air to the sheet-shaped liquid material SLM.

[0122] In addition, in the case in which the drying treatment section 41 is provided, it is also possible to provide a solvent recovery mechanism that cools and liquefies the volatilized solvent generated in the drying treatment section 41 and recovers it. It is possible to provide the solvent recovery mechanism, and further recycle and reuse the solvent recovered here as a raw material solvent. By reusing like this, it is possible to reduce costs and efficiently perform sheet manufacturing with respect to the sheet manufacturing operation of the present embodiment.

[0123] The drying treatment section 42 is disposed in the curing region 32, and is a member that further dries the solvent remaining in the sheet peeled from the heating roller 31. The drying treatment section 42 can be configured in the same manner as the drying treatment section 21 described in Embodiment 2. Note that, in the present embodiment, since the drying treatment section 41 mainly volatilizes the solvent, the drying treatment section 42 is a portion that performs an operation of further drying the remaining solvent, and functions as an auxiliary. Therefore, as the drying treatment section, it is also possible to omit the drying treatment section 42 and configure only the drying treatment section 41.

[0124] <Sheet Manufacturing Method>

[0125] In this modification, the manufacturing apparatus 40 of the sheet used is as described above, and is different from the manufacturing apparatus 30 of the sheet only in whether or not the drying treatment sections 41, 42 are provided. Therefore, the basic operation in the manufacturing method of the sheet is the same as in Embodiment 3.

[0126] In this modification, on the basis of the operation in Embodiment 3, the solvent contained in the liquid material is volatilized and dried by the drying treatment section 41 with respect to the liquid material applied to the heating roller 31, and the sheet-shaped liquid material SLM is efficiently formed into the sheet 50. This drying operation is performed in the solidification region 32.

[0127] In addition, the solvent recovery mechanism can be provided in the above-described manner, and the solvent volatilized in the drying treatment section 41 is cooled to be liquefied and recovered. The solvent thus recovered can be recycled as the solvent of the raw material.

[0128] <Raw Material>

[0129] Next, the raw material used in Embodiments 1 to 3 will be described. Here, the raw material is not particularly limited, and as described above, as the liquid material for application by the applicator 13, only a liquid material having a viscosity of 100,000 mPa-s or less is necessary. This liquid material can be adjusted by melting the raw material or by mixing and dissolving the raw material with a solvent.

[0130] As this raw material, for example, in molding of resins and the like, a resin in which a so-called injection grade, a spinning grade, or the like, a low-viscosity liquid resin is ejected from a mold can be exemplified.

[0131] In addition, as the raw material, a biodegradable material or the like can also be used. As the biodegradable material in the present application, a water-soluble material is suitable, and since it is easy to use water as a solvent to dissolve it to obtain a low-viscosity liquid material, not only is the moldability excellent, but also this is excellent in terms of low environmental load.

[0132] As the raw material that can be used in the present embodiment, for example, polysaccharides, gelatin, and the like can be exemplified, and as the polysaccharides, for example, glucomannan, a cellulose-based material, pectin, starch, isomaltulose, agar, and the like can be exemplified, and these raw materials can be used alone or two or more can be used in combination. In particular, it is preferable to contain at least one selected from the group consisting of glucomannan, a cellulose-based material, gelatin, and agar.

[0133] Glucomannan is a water-soluble polysaccharide contained in about 10% of the tuber of konjac, and can be extracted by alcohol purification of konjac powder. Glucomannan has Figure 6The chemical structure shown is a polysaccharide in which D-glucose and D-mannose are β-1, 4-bonded in a ratio of 1:1.6 (n represents the number of repeating units of the constitutional unit). It has a branched chain in a ratio of 1 per 50 to 60 sugars, has a large molecular weight, and sometimes exceeds 1 million.

[0134] The glucomannan used here is preferably in the range of 20 to 2 million in molecular weight. The glucomannan having such a molecular weight has a viscosity of 1000 to 20000 mPa-s when 1 mass% is added to water and melted.

[0135] In addition, the glucomannan has a large number of hydroxyl groups, and by using an alcohol as a solvent to dissolve it, low viscosity can be easily achieved.

[0136] The cellulose-based material is a material that contains cellulose or contains cellulose in part. Cellulose is a naturally occurring high molecule in which a large number of β-glucose molecules are polymerized into a straight chain by glycosidic bonds, has a molecular weight of 2000 to 20 million, and has a viscosity of 10 to 5000 mPa-s when 1 mass% is added to water and melted. Figure 7 The chemical structure shown is a carbohydrate (polysaccharide) represented by the formula (C6H 10 O5) n As the cellulose-based material, for example, carboxymethyl cellulose, cellulose nanofiber, and the like can be given.

[0137] The cellulose-based material used here is preferably in the range of 2000 to 20 million in molecular weight. The cellulose-based material having such a molecular weight has a viscosity of 10 to 5000 mPa-s when 1 mass% is added to water and melted.

[0138] In addition, the cellulose-based material has a large number of hydroxyl groups, and by using an alcohol as a solvent to dissolve it, low viscosity can be easily achieved.

[0139] Gelatin is a fibrous protein collagen, and agar is a substance obtained by freezing / drying a mucilage of a red algae, is itself insoluble in water, but can be melted by heating to achieve low viscosity.

[0140] In addition, the above-mentioned liquid material can also contain a filler. As the filler, for example, inorganic substances such as alumina, silica, aluminum hydroxide, boehmite, cellulose (including cellulose nanofiber), carbon fiber, carbon nanotube, carbon nanofiber, graphene, fullerene, aramid fiber, and the like can be used. As the cellulose, a substance in which the hydrophilic group of cellulose is replaced with a hydrophobic group can also be used.

[0141] (Embodiment 4)

[0142] <Sheet>

[0143] The sheet material of this embodiment comprises a sheet-like molded body formed using the low-viscosity liquid material described above. As described above, the low-viscosity liquid material is a material obtained by melting a raw material or dissolving a raw material in a solvent. The raw material preferably contains at least one selected from glucomannan, a cellulose-based material, gelatin, and agar.

[0144] The sheet material may be a sheet-shaped molded body itself or a sheet-shaped molded body with its surface subjected to various treatments. The thickness of the sheet material can be set to any thickness, but is preferably 10 μm to 5 mm, more preferably 20 μm to 3 mm.

[0145] In addition, the sheet-like molded body can be a sheet of a multilayer structure formed by stacking two or more layers. In this case, all layers can be the sheet of this embodiment, or some layers can be the sheet of this embodiment and the other layers can be the sheet of a layer other than this embodiment. That is, it is sufficient to have one or more layers of the sheet-like molded body used in this embodiment.

[0146] The following describes a specific example of a sheet material using glucomannan as a raw material. First, glucomannan manufactured by Now Foods was prepared. This glucomannan was added to water at a concentration of 0.5 wt% and melted to create a liquid material with a viscosity of 10,000 mPa·s. Since this liquid material achieved this viscosity without the use of a solvent, the liquid material can be prepared using glucomannan alone.

[0147] The liquid material obtained by heating in this way is used, for example, Figure 1 Sheet 50 was manufactured using the sheet manufacturing apparatus 10 shown. A 40 cm wide, 0.5 mm thick polyethylene (PE) sheet with a silicone release layer on its surface was used as the substrate BM. The substrate BM was fed at a conveying speed of 0.1 m / s. Furthermore, the liquid material LM was applied to the substrate from a coater 13 (die coater) with a 1 mm slit width at a rate of 3000 mL / min.

[0148] The sheet-like liquid material SLM is solidified by natural cooling at room temperature and conveyed by the feed roller 19 to produce a laminate of the sheet 50 and the base material BM. The sheet 50 is then peeled from the base material BM by the peeling member 15. The peeled sheet 50 having a thickness of 0.5 μm can be wound up by the sheet winding unit 16 to produce a roll of the sheet 50.

[0149] The glucomannan sheet thus prepared can be used as a water-absorbent sheet utilizing the hygroscopicity of the raw material. Figure 8 and 9Examples of use of the water-absorbing sheet are described. In these figures, arrows indicate movement of thermal energy.

[0150] Figure 8 and Figure 9 is an example of a case where the sheet 50 made of glucomannan is used as a water-absorbing sheet in a case where solar light is used. The moisture recovery device 100 shown here is composed of a heat collector 101, a heat storage tank 102, an inclined plate 103, and a moisture recovery container 104.

[0151] The heat collector 101 is, for example, a device that is able to obtain thermal energy from solar light and move it to the heat storage tank 102. The heat storage tank 102 is a portion that stores heat collected by the heat collector 101, and the stored heat can be used to heat the sheet 50 at a desired timing. The inclined plate 103 is a plate-shaped body that is arranged inclined above the sheet 50. This inclined plate 103 is a configuration that causes water vapor emitted from the sheet 50 to cool and liquefy and be guided to the moisture recovery container 104. The moisture recovery container 104 is a container that stores the liquefied water guided by the inclined plate 103.

[0152] This moisture recovery device 100 is used, for example, as follows. First, as shown in Figure 8 , the heat energy of solar light is collected by the heat collector 101 during the day, and the heat energy collected here is stored in the heat storage tank 102. Here, the sheet 50 is exposed to the outside atmosphere and absorbs moisture (water vapor) contained in the air. As described above, the sheet 50 made of glucomannan has excellent moisture absorption properties and is able to hold a large amount of moisture.

[0153] Next, at night when the sun sets, as shown in Figure 9 , the sheet 50 is heated using the heat energy stored in the heat storage tank 102. This heating is set to a temperature at which the sheet 50 emits (dehumidifies) moisture absorbed by the sheet 50, and is, for example, preferably 80 to 100°C. Here, the moisture emitted from the sheet 50 spreads upward above the sheet 50, comes into contact with the inclined plate 103, and liquefies on the surface of the inclined plate 103. The liquefied moisture flows along the inclination of the inclined plate 103 toward the lower side of the inclined plate 103, is guided to the moisture recovery container 104, and is finally contained in the moisture recovery container 104.

[0154] The present application has been specifically described above by means of embodiments and examples, but the present application is not limited in interpretation to these embodiments and examples, and of course various modifications can be made within the scope of the gist thereof.

[0155] Explanation of Reference Signs

[0156] 10, 20, 30, 40 sheet manufacturing device

[0157] 11 raw material container

[0158] 12 base material carrying-out portion

[0159] 13 coater

[0160] 14, 32 curing area

[0161] 15, 33 peeling member

[0162] 16 sheet take-up section

[0163] 17 base material take-up section

[0164] 18 back roll

[0165] 19 feed roll

[0166] 21, 41, 42 drying treatment section

[0167] 31, 31a, 31b, 31c heating roll

[0168] 50 sheet

[0169] BM base material

[0170] LM liquid material

[0171] SLM sheet-like liquid material

Claims

1. A method for producing a sheet material, comprising the following steps: (a) step, adjusting the liquid material containing the raw material to have a viscosity of 100,000 mPa·s or less; (b) step, after the step (a), applying the liquid material in a sheet form by a coating machine to form a coated body; (c) a step of curing the coated body to obtain a sheet after the step (b); and (d) step: after the step (c), the sheet is wound up.

2. The method for producing a sheet according to claim 1, wherein: In the step (b), the liquid material is applied to a substrate in a sheet form.

3. The method for producing a sheet according to claim 2, wherein: After the step (c) and before the step (d), the sheet is peeled from the substrate.

4. The method for producing a sheet according to claim 3, wherein: A silicone or non-silicone release agent is applied to the surface of the substrate.

5. The method for producing a sheet according to claim 1, wherein: In the step (b), the liquid material is applied to a heating roller in a sheet form.

6. The method for producing a sheet material according to claim 5, wherein: The coated body applied on the heating roller is dried while passing through another heating roller.

7. The method for producing a sheet according to claim 1, wherein: As the raw material, a powdered filler containing at least one selected from glucomannan, a cellulose-based material, gelatin, and agar is used.

8. The method for producing a sheet according to claim 1, wherein: The liquid material comprises the raw material and a solvent, The step (c) includes a drying step of volatilizing the solvent by heating.

9. The method for producing a sheet material according to claim 8, wherein: The solvent is water or alcohol.

10. A sheet material manufacturing device, comprising: A raw material container for adjusting and storing a liquid material containing a raw material and having a viscosity of 100,000 mPa·s or less; a substrate carrying-out unit for delivering the substrate; a coating machine for coating the liquid material in a sheet form on the substrate delivered from the substrate delivery portion; a curing region for curing the coating body coated on the substrate to form a sheet; a peeling member that peels the sheet from the substrate in a subsequent section of the curing zone; as well as A sheet winding section winds up the sheet peeled from the base material.

11. A sheet material manufacturing device, comprising: A raw material container for adjusting and storing a liquid material containing a raw material and having a viscosity of 100,000 mPa·s or less; a coating machine for coating the liquid material in a sheet form on a heated roller; a curing area for curing the coating body applied on the heating roller to form a sheet; a peeling member that peels the sheet from the heated roller in the curing area; and A sheet winding section winds up the sheet peeled from the heating roller.

12. The sheet material manufacturing apparatus according to claim 10 or 11, wherein: The curing area includes a drying treatment section for volatilizing the solvent in the sheet by heating.

13. The sheet material manufacturing apparatus according to claim 10 or 11, wherein: The liquid material comprises the raw material and a solvent, The solidification area includes a recovery unit for recovering the volatilized solvent.

14. A sheet material, wherein The invention comprises a sheet-like molded body containing at least one selected from glucomannan, a cellulose-based material, gelatin and agar.

15. The sheet material according to claim 14, wherein The sheet has a multilayer structure in which two or more layers are stacked, and has one or more layers of the sheet-like molded body.

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