WO2024162246A1 - 断熱シート及びその製造方法、断熱繊維及びその製造方法、並びに断熱シートの製造に用いられる繊維含有懸濁液 - Google Patents

断熱シート及びその製造方法、断熱繊維及びその製造方法、並びに断熱シートの製造に用いられる繊維含有懸濁液 Download PDF

Info

Publication number
WO2024162246A1
WO2024162246A1 PCT/JP2024/002618 JP2024002618W WO2024162246A1 WO 2024162246 A1 WO2024162246 A1 WO 2024162246A1 JP 2024002618 W JP2024002618 W JP 2024002618W WO 2024162246 A1 WO2024162246 A1 WO 2024162246A1
Authority
WO
WIPO (PCT)
Prior art keywords
fibers
heat insulating
fiber
insulating
fine particles
Prior art date
Application number
PCT/JP2024/002618
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
ラダー ウー
官益 李
和夫 小沼
Original Assignee
株式会社Thermalytica
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社Thermalytica filed Critical 株式会社Thermalytica
Priority to JP2024574882A priority Critical patent/JPWO2024162246A1/ja
Publication of WO2024162246A1 publication Critical patent/WO2024162246A1/ja

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
    • D04H1/58—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by applying, incorporating or activating chemical or thermoplastic bonding agents, e.g. adhesives
    • D04H1/587—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by applying, incorporating or activating chemical or thermoplastic bonding agents, e.g. adhesives characterised by the bonding agents used
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
    • D06M11/00—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising
    • D06M11/77—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with silicon or compounds thereof
    • D06M11/79—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with silicon or compounds thereof with silicon dioxide, silicic acids or their salts
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/36—Inorganic fibres or flakes
    • D21H13/38—Inorganic fibres or flakes siliceous
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/20—Macromolecular organic compounds
    • D21H17/33—Synthetic macromolecular compounds
    • D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H17/36—Polyalkenyalcohols; Polyalkenylethers; Polyalkenylesters
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/63—Inorganic compounds
    • D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
    • D21H17/68—Water-insoluble compounds, e.g. fillers, pigments siliceous, e.g. clays
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L59/00—Thermal insulation in general
    • F16L59/02—Shape or form of insulating materials, with or without coverings integral with the insulating materials

Definitions

  • the present invention relates to a heat insulating sheet and a method for producing the same, a heat insulating fiber and a method for producing the same, and a fiber-containing suspension used in the production of a heat insulating sheet.
  • insulating and heat-resistant properties are attracting attention as a measure against global warming.
  • a structure is adopted in which an insulating sheet is sandwiched between adjacent cells to reduce the impact that overheating in some cells has on adjacent cells.
  • the insulating sheet sandwiched between the cells must be heat-resistant to prevent the cells from overheating and causing thermal runaway, and must also be flame-retardant and fire-resistant in case of fire.
  • the insulating sheet must be as thin as possible. In this way, insulating sheets are required to achieve the required insulating and flame-retardant properties while being as thin as possible.
  • Patent Document 1 discloses a resin-coated flame-retardant fiber yarn. It is said that the flame-retardant fiber yarn is coated with two resin coating layers, and the outer layer contains titanium dioxide particles, thereby achieving light transmission, heat insulation, and flame retardancy.
  • the manufacturing method is described as follows: A resin solution containing a titanium dioxide-free adhesive resin is applied to a glass fiber bundle, which is a flame-retardant fiber yarn, and after squeezing out the excess resin solution, the bundle is heated to form an inner resin coating layer.
  • a resin solution containing titanium dioxide is applied to the glass fiber bundle on which the inner resin coating layer has been formed, and after squeezing out the excess resin solution, the bundle is heated to form a resin layer containing titanium dioxide on the outside of the inner resin coating layer (for details, see paragraphs 0026 to 0045 of the same document). It is said that a woven fabric can be made by weaving this resin-coated flame-retardant fiber yarn as the warp and weft (ibid., paragraph 0046).
  • Patent Document 2 discloses a lightweight heat and sound insulation material with excellent heat insulation and sound insulation properties.
  • the basic structure is a cell in which an aggregate of silica aerogel particles is surrounded by a network of organic nanofibers with anionic functional groups, and a solid composite with a three-dimensional continuous structure in which multiple cells are closely spaced is formed inside a nonwoven fabric or open-cell foam, which is said to be lightweight and have excellent sound insulation properties.
  • Patent Document 3 discloses ultrafine aerogel particles, which are made from aerogel having a three-dimensional network structure in which the skeleton is formed by clusters, which are aggregates of primary particles, and which contain fine particles having a three-dimensional network structure in which the skeleton is formed by the primary particles.
  • Patent Document 3 is an invention by the inventors of the present application, and is commercially known as TIISA (a registered trademark of Thermalytica Co., Ltd.).
  • Ultrafine aerogel particles have a thermal conductivity equivalent to that of high-performance aerogel, and a bulk density of 0.01 g/cm 3 or less, which is about one-tenth or less of that of general aerogel. Therefore, they are lightweight and high-performance heat insulating materials.
  • Ultrafine aerogel particles are extremely fine particles because their skeleton is formed mainly by primary particles that constitute the secondary particles, whereas the skeleton of general aerogel is formed by secondary particles, and are characterized in that more than 50% of their volume is dispersed with a particle diameter of 0.1 ⁇ m to 1.0 ⁇ m as a mode value.
  • Patent Document 4 discloses a fiber-reinforced thermoplastic resin sheet and a glass fiber nonwoven fabric carrying silica microparticles.
  • the fiber-reinforced thermoplastic resin sheet is composed of a thermoplastic matrix resin and silica microparticles contained in the glass fibers and having an average primary particle diameter in the range of 1 to 100 nm.
  • Patent Document 5 discloses a heat insulating material that is said to have high strength and excellent heat insulating properties.
  • the heat insulating material is composed of aerogel particles, an adhesive that bonds them, and a composite adhesive in which a heat-fusible adhesive component is coated with a protective film.
  • the primary object of the present invention is to provide an insulating sheet having high insulating performance. Another object of the present invention is to further impart flame retardant performance to the insulating sheet. Yet another object of the present invention is to provide a fiber-containing suspension and insulating fibers suitable for producing such an insulating sheet.
  • the insulating sheet of the present invention is an insulating sheet containing base fibers and insulating microparticles, the base fibers are bonded to each other or woven to form a sheet body, and the insulating microparticles are present inside and/or outside the base fibers.
  • the method for manufacturing the insulating sheet according to the present invention includes the steps of dispersing insulating microparticles to prepare an insulating microparticle-containing suspension, dissolving a binder to prepare a binder solution, mixing the insulating microparticle-containing suspension, the binder solution, base fibers, and binder fibers to prepare a fiber-containing suspension, and removing liquid components from the fiber-containing suspension to form a sheet (papermaking process).
  • Another method for manufacturing a heat insulating sheet according to the present invention includes the steps of: mixing a thermoplastic resin with heat insulating particles to obtain a resin containing microparticles; storing the resin containing microparticles in a container having fine holes arranged in a chamber; rotating the container while heating it to eject the resin containing microparticles from the fine holes to obtain short fibers; and forming the short fibers into a sheet.
  • a further method for producing a heat insulating sheet according to the present invention includes the steps of melting a thermoplastic resin and mixing the melted thermoplastic resin with heat insulating microparticles to prepare a microparticle-containing resin, extruding the melted microparticle-containing resin through pores to obtain fibers, spinning the fibers to obtain yarn, and weaving and knitting the yarn.
  • the fiber-containing suspension for manufacturing the insulating sheet of the present invention is a mixture of an insulating microparticle-containing suspension in which insulating microparticles are dispersed in a solvent, a binder solution, base fibers, and binder fibers.
  • a fiber-containing suspension for manufacturing a heat insulating sheet is a mixture of a heat insulating microparticle-containing suspension in which heat insulating microparticles are dispersed in a solvent, a binder solution, heat insulating fibers, and binder fibers, and the heat insulating fibers are formed by bonding heat insulating microparticles for fibers to the surface of a base fiber with a binder for fibers, and the heat insulating microparticles for fibers are made of aerogel having a three-dimensional mesh structure with a skeleton composed of clusters that are aggregates of primary particles, and are microparticles having a three-dimensional mesh structure with a skeleton composed of the primary particles, with 50% or more of their volume being dispersed with a mode of particle diameter of 0.1 ⁇ m to 1.0 ⁇ m, and the base fiber is silica fiber.
  • the insulating fiber of the present invention has insulating fine particles bonded to the surface of a base fiber by a binder, the insulating fine particles are made of aerogel having a three-dimensional mesh structure with a skeleton made of clusters that are aggregates of primary particles, the insulating fine particles have a three-dimensional mesh structure with a skeleton made of the primary particles, and 50% or more of the volume of the insulating fine particles are fine particles dispersed with a mode of particle diameter of 0.1 ⁇ m to 1.0 ⁇ m, and the base fiber is silica fiber.
  • Another insulating fiber according to the present invention has insulating microparticles present inside a matrix fiber in a state where they are at least partially embedded, the insulating microparticles are made from an aerogel having a three-dimensional mesh structure with a skeleton made up of clusters that are aggregates of primary particles, the insulating microparticles have a three-dimensional mesh structure with a skeleton made up of the primary particles, and 50% or more of the volume of the insulating microparticles are microparticles dispersed with a mode of particle diameters of 0.1 ⁇ m to 1.0 ⁇ m, and the matrix fiber contains a thermoplastic resin.
  • the method for producing the insulating fiber according to the present invention is a method for producing the insulating fiber according to the present invention, and includes the steps of dispersing the insulating microparticles to prepare an insulating microparticle-containing suspension, dissolving a binder to prepare a binder solution, mixing the insulating microparticle-containing suspension and the binder solution to prepare a slurry, and depositing the slurry as an evaporation source onto the base fiber.
  • Another method for producing insulating fibers according to the present invention is the same as the method for producing insulating fibers according to the present invention, and includes the steps of dissolving a binder to prepare a binder solution, depositing the binder solution onto base fibers as an evaporation source, and mechanically coating the base fibers with insulating fine particles on the surfaces of which the binder solution has been attached by the deposition.
  • “dispersing (the fine particles)” means putting the fine particles into a liquid and dispersing them in the liquid, not dissolving them.
  • the “papermaking process (sheet formation process)” includes the process of thinly spreading a suspension containing base fibers, removing excess liquid, and then drying to form a sheet.
  • “polyvinyl alcohol” may be abbreviated to “PVA” (polyvinyl alcohol), “polyvinyl alcohol fiber” to “PVA fiber,” and “polyvinyl alcohol powder” to “PVA powder.”
  • FIG. 1 is a schematic explanatory diagram showing an example of the configuration of a heat insulating sheet according to one embodiment of the present invention.
  • FIG. 2 is an explanatory diagram showing the relationship between the lengths of the base fibers and the binder fibers.
  • FIG. 3 is an explanatory diagram showing an example of the configuration of a flame-retardant fiber formed by adhering heat insulating fine particles to the surface of a base fiber.
  • FIG. 4 is a flow chart showing an example of a method for producing a heat insulating sheet according to an embodiment of the present invention.
  • FIG. 5 is a flow chart illustrating an example of a method for producing a flame-retardant fiber according to one embodiment of the present invention.
  • FIG. 1 is a schematic explanatory diagram showing an example of the configuration of a heat insulating sheet according to one embodiment of the present invention.
  • FIG. 2 is an explanatory diagram showing the relationship between the lengths of the base fibers and the binder fibers.
  • FIG. 6 is a flow chart showing an example of a method for manufacturing a heat insulating sheet having flame retardant properties.
  • FIG. 7 is an explanatory diagram showing the structure of an ultrafine aerogel particle, which is an example of a heat insulating particle.
  • FIG. 8 is an explanatory diagram illustrating the particle size distribution of ultrafine aerogel particles, which are an example of heat insulating particles.
  • FIG. 9 is a photograph showing the results of an experiment in which glass wool coated with a flame-retardant layer containing ultrafine aerogel particles was heated with a flame.
  • FIG. 10 is an optical microscope photograph showing the results of an experiment in which glass wool coated with a flame-retardant layer containing ultrafine aerogel particles was heated with a flame.
  • FIG. 10 is an optical microscope photograph showing the results of an experiment in which glass wool coated with a flame-retardant layer containing ultrafine aerogel particles was heated with a flame.
  • FIG. 11 is an explanatory diagram showing an example of a base fiber formed by mixing a thermoplastic resin and heat insulating particles.
  • FIG. 12 is a flowchart showing an example of a method for producing a heat insulating sheet according to the eighth embodiment.
  • FIG. 13 is an explanatory diagram showing an example of the configuration of an apparatus for producing base fibers of the heat insulating sheet according to the eighth embodiment.
  • FIG. 14 is a flowchart showing an example of a method for producing a heat insulating sheet according to the ninth embodiment.
  • FIG. 15 is a schematic diagram showing an example of a known spinning apparatus.
  • FIG. 16 is a schematic diagram showing the apparatus used in the examples.
  • FIG. 17 is a scanning electron microscope (SEM) photograph showing the experimental results.
  • SEM scanning electron microscope
  • Heat insulating sheet carrying heat insulating particles (Fig. 1, Fig. 11)
  • the insulating sheet shown in this embodiment is an insulating sheet (100) including base fibers (6,300) and insulating microparticles (1, 14), in which the base fibers (6,300) are bonded to each other or woven or knitted to form a sheet body, and the insulating microparticles (1, 14) are present inside and/or outside the base fibers (6,300).
  • the heat insulating microparticles are made from an aerogel having a three-dimensional mesh structure with a skeleton composed of clusters that are aggregates of primary particles, and are microparticles having a three-dimensional mesh structure with a skeleton composed of the primary particles, with 50% or more of the volume being dispersed with a particle diameter of 0.1 ⁇ m or more and 1.0 ⁇ m or less as a mode.
  • a heat insulating sheet in which heat insulating particles are supported in the gaps between the base fibers bonded together by a film formed by dissolving the binder fibers ( Figure 1)
  • the base fiber is a silica fiber
  • the insulating sheet (100) includes a base fiber (6), a binder fiber (7), and a bonding agent (2, not shown in Figure 1), the base fibers are bonded to each other by a film formed by dissolving the binder fiber, and the insulating microparticles (1) are supported in the gaps between the bonded base fibers by the bonding agent.
  • the presence of the insulating microparticles on the surface of the base fiber imparts flame retardancy in addition to insulating properties, making it possible to impart flame retardancy to the entire insulating sheet.
  • “adding flame retardancy” refers to performing some kind of processing on a specific object, making that object less flammable than before the processing.
  • a heat insulating sheet formed by weaving and knitting a base material fiber carrying heat insulating particles embedded in a thermoplastic resin (FIG. 11)
  • the base fiber (300) contains a thermoplastic resin (8)
  • the heat insulating microparticles (14) are present in a state in which at least a portion of them is embedded in the thermoplastic resin (8) in the base fiber (300)
  • the sheet body is formed by weaving and knitting yarns spun from the base fiber (300).
  • the base fiber (300) is spun by a known spinning method, and the spun yarn is woven or knitted by a known method to form a sheet body, which is an insulating sheet.
  • thermoplastic resin a thermoplastic resin (8)
  • the insulating particles (14) are present in a state in which at least a portion of them is embedded in the thermoplastic resin (8) in the base fiber (300)
  • the sheet body is formed by bonding the base fibers to each other with a film formed by melting the thermoplastic resin.
  • a representative embodiment of the present invention is a method for producing a heat insulating sheet, which includes the following steps.
  • S2 A step of dissolving a binder to prepare a binder solution.
  • S3 A step of mixing the heat insulating microparticle-containing suspension, the binder solution, base fibers, and binder fibers to prepare a fiber-containing suspension.
  • Paper making process, S4) A process of removing the liquid component from the fiber-containing suspension to form a sheet body.
  • the base fiber is a silica fiber
  • the insulating microparticles are made from an aerogel having a three-dimensional mesh structure with a skeleton composed of clusters that are aggregates of primary particles, and are microparticles having a three-dimensional mesh structure with a skeleton composed of the primary particles, and 50% or more of the volume of the microparticles are dispersed with a particle diameter of 0.1 ⁇ m or more and 1.0 ⁇ m or less as a mode.
  • a method for producing a heat insulation sheet according to another embodiment of the present invention includes the following steps.
  • thermoplastic resin and insulating microparticles are mixed to obtain a microparticle-containing resin.
  • the process involves placing the microparticle-containing resin in a container with fine holes, and rotating the container while heating it to eject the microparticle-containing resin from the fine holes to obtain short fibers.
  • a method for producing an insulating sheet in which the insulating sheet is produced by weaving or knitting staple fibers includes a step of spinning the staple fibers to obtain yarn, and a step of weaving or knitting the yarn.
  • a method for manufacturing an insulating sheet by molding short fibers In the step of molding the short fibers into a sheet in the method for manufacturing an insulating sheet of [10], the short fibers are spread into a thin film and heated to form the sheet.
  • a method for manufacturing a heat insulating sheet by weaving or knitting a heat insulating sheet from spun yarn includes the following steps.
  • a representative embodiment of the present invention is a method for producing a heat insulating sheet, which includes the following steps.
  • the heat insulating fiber has heat insulating fine particles for fiber bonded to the surface of the base fiber by a binder for fiber
  • the insulating microparticles for the fibers are made from aerogel having a three-dimensional mesh structure with a skeleton made up of clusters that are aggregates of primary particles, and are microparticles having a three-dimensional mesh structure with a skeleton made up of the primary particles, with 50% or more of their volume being dispersed with a particle diameter of 0.1 ⁇ m or more and 1.0 ⁇ m or less as the most frequent value, and the base fiber is silica fiber.
  • This provides a method for producing flame-retardant fibers even when the insulating microparticles are hydrophobic.
  • Fiber-containing suspension A typical embodiment of the present invention is a fiber-containing suspension for producing an insulating sheet, which is a mixture of an insulating microparticle-containing suspension in which insulating microparticles are dispersed in a solvent, a binder solution, base fibers, and binder fibers, used in the method for producing the insulating sheet.
  • a typical embodiment of the present invention is a fiber-containing suspension for producing an insulating sheet, which is used in the method for producing an insulating sheet, and which comprises a mixture of an insulating microparticle-containing suspension in which insulating microparticles are dispersed in a solvent, a binder solution, insulating fibers, and binder fibers, and the insulating fibers are formed by bonding insulating microparticles for the fibers to the surface of a base fiber with a binder for the fibers, the insulating microparticles for the fibers are made from aerogel having a three-dimensional mesh structure with a skeleton composed of clusters that are an aggregate of primary particles, and are microparticles having a three-dimensional mesh structure with a skeleton composed of the primary particles, with 50% or more of their volume being dispersed with a particle diameter of 0.1 ⁇ m or more and 1.0 ⁇ m or less as a mode, and the base fiber is silic
  • This fiber-containing suspension can be provided as a raw material for the papermaking process (S4), etc.
  • a representative embodiment of the present invention is a heat insulating fiber (flame retardant fiber) (200) to which flame retardancy has been added, and is configured as follows.
  • the flame retardant fiber refers to a heat insulating fiber to which flame retardancy has been added as well as heat insulating properties.
  • the insulating particles (1) are bonded to the surface of the base fiber (6) with a binder (2).
  • the insulating microparticles are made from aerogel, which has a three-dimensional mesh structure with a skeleton made up of clusters that are aggregates of primary particles, and are microparticles with a three-dimensional mesh structure with a skeleton made up of the primary particles, with 50% or more of their volume being dispersed with a particle diameter of 0.1 ⁇ m to 1.0 ⁇ m as the mode.
  • the matrix fiber is silica fiber.
  • FIG. 1 An exemplary embodiment of the present invention is an insulating fiber (300) constructed as follows.
  • the heat insulating particles (14) are present in a state where they are at least partially embedded inside the base fiber (300),
  • the heat insulating fine particles (14) are made from an aerogel having a three-dimensional network structure with a skeleton formed of clusters that are aggregates of primary particles, and are fine particles having a three-dimensional network structure with a skeleton formed of the primary particles, with 50% or more of the volume of the fine particles being dispersed with a mode of particle diameter of 0.1 ⁇ m or more and 1.0 ⁇ m or less
  • the matrix fiber (300) comprises a thermoplastic resin (8).
  • a manufacturing method for imparting high flame retardancy to base fibers by depositing insulating fine particles (ultrafine aerogel particles) contained in the slurry onto the surface of the base fibers.
  • This provides another manufacturing method for imparting flame retardancy to matrix fibers.
  • insulating particles (ultrafine aerogel particles) to be more efficiently bonded to the surface of the silica fiber, which is the base fiber.
  • This provides a method for producing flame-retardant fibers even when the insulating microparticles are hydrophobic.
  • Fig. 1 is a schematic explanatory diagram showing an example of the structure of the heat insulating sheet of the present invention.
  • the heat insulating sheet 100 of the present invention contains base material fibers 6, binder fibers 7, and a binder (2, not shown in Fig. 1), the base material fibers 6 are bonded to each other by a film (not shown in Fig. 1) formed by dissolving the binder fibers 7, and heat insulating particles 1 are carried in the gaps between the bonded base material fibers 6.
  • the reference numeral 3 will be described later and in more detail in embodiments 4 and 5.
  • binder fiber 7 for example, polyvinyl alcohol (PVA) fiber, polyester fiber, polyester composite fiber, acrylic fiber, acrylic fiber, nylon, polyurethane fiber, polycarbonate fiber, etc. can be used.
  • PVA polyvinyl alcohol
  • the binding agent polyvinyl alcohol (PVA) powder, methyl cellulose, starch paste, gum arabic paste, etc. can be used.
  • the length of the binder fiber 7 is preferably several tens of micrometers.
  • the matrix fiber 6 is, for example, silica fiber, and is several tens of millimeters longer than the binder fiber 7. While the matrix fiber 6 extends in a plane (horizontal direction in FIG. 1), the binder fiber 7 plays a role in connecting the matrix fiber 6 vertically (thickness direction of the heat insulating sheet 100).
  • the matrix fiber 6 and the binder fiber 7 are bonded to each other by a film (not shown in FIG. 1) formed by melting, and gaps are formed in the bonded matrix fiber 6, in which the heat insulating particles 1 are supported.
  • PVA fiber which is an example of the binder fiber 7, melts and becomes a film when heated to 65°C to 85°C in a water-wet state.
  • Melt refers to dissolving in water, not melting due to heat.
  • Matrix fibers 6 such as silica fiber have mechanical strength, but heat is conducted along the fibers, so heat insulating performance cannot be expected.
  • the base material fibers 6 are long and extend in a direction parallel to the front and back surfaces of the sheet, providing the heat insulating sheet 100 with mechanical strength in the planar direction.
  • the heat insulating particles 1 are supported in the gaps between the base material fibers 6 as shown in FIG. 1, thereby providing the heat insulating sheet 100 with heat insulating performance in the thickness direction.
  • binder fiber 7 In general, insulation sheets are required to have better insulation performance in the thickness direction than in the in-plane direction. For this reason, binder fibers that reach from one surface of the insulation sheet to the other surface are not preferred.
  • the thermal conductivity of binder fibers is higher than that of silica fibers, which are often used as base fibers, so if binder fibers reach from one surface to the other surface of the insulation sheet in the thickness direction, heat will be conducted through the binder fibers, which will act to reduce the insulation performance in the thickness direction.
  • the length of the binder fibers should preferably be at most a few mm, which is approximately the same as the thickness of the insulation sheet.
  • the appropriate minimum length of the binder fiber 7 is 10 ⁇ m to several tens of ⁇ m.
  • Figure 2 is an explanatory diagram showing the relationship between the lengths of the base material fibers 6 and the binder fibers 7. When the base material fibers 6 are adjacent to each other so as to be in contact with each other (a), the binder fibers 7 are required to have a length equal to or greater than the diameter of the base material fibers 6 in order to bond the adjacent base material fibers 6.
  • the minimum length of the binder fibers 7 required is one to several times the distance between the base material fibers 6 to be connected. That is, when two fibers are connected (b), it is about the same as the distance between the base material fibers 6, when three fibers are connected in a straight line (c), it is about twice the distance between the base material fibers 6, and when three fibers are connected in a stitching manner (d), it is about three to four times the distance between the base material fibers 6.
  • the diameter of silica fibers which are generally used as base fibers, is 8 ⁇ m to 12 ⁇ m according to measurements by the inventors, so the minimum value is set to be within several times this value. Note that the minimum value mentioned here does not mean that there are no binder fibers shorter than this length, but simply means that binder fibers shorter than this length have a small contribution to the purpose of bonding the base fibers.
  • the strength and heat insulating performance can be adjusted by appropriately designing the length of the base fiber 6 and the binder fiber 7.
  • the insulating fine particles 1 it is preferable to use the ultrafine aerogel particles described in Patent Document 3.
  • Figure 7 is an explanatory diagram showing a comparison of the structures of general aerogel fine powder and ultrafine aerogel particles whose skeleton is formed by primary particles.
  • the three-dimensional mesh structure of general aerogel fine powder 13 is composed of units of secondary particles 12, which are clusters of primary particles 11 ( Figure 7(a)), whereas ultrafine aerogel particles 14 have a three-dimensional mesh structure formed with the primary particles 11 as the skeleton ( Figure 7(b)).
  • Aerogels that are generally available are granules that have a three-dimensional mesh structure with a skeleton consisting of secondary particles 12 as units, so even if they are finely crushed using a crushing device, the skeleton structure does not change.
  • Figure 8 is an explanatory diagram showing an example of the frequency distribution of particle sizes for aerogel granules, aerogel powder, aerogel fine powder, and aerogel ultrafine particles, which are fine particles with a skeleton formed by primary particles, in order from the bottom.
  • the aerogel granules are the aerogel granules that are generally available.
  • the aerogel powder is an aerogel powder produced by crushing aerogel granules at 5000 to 7000 rpm for 2 minutes using a Spin Mix Homogenizer SX08 manufactured by Mitsui Electric Seiki Co., Ltd.
  • the aerogel fine powder is a fine powder produced by crushing aerogel granules at 21000 rpm for 20 seconds using a STEALTH885 manufactured by Blendtec Co., Ltd., in an attempt to further reduce the particle size.
  • the horizontal axis of Figure 8 is the particle size, and the vertical axis is the frequency distribution of the relative particle amount.
  • the right vertical axis shows the frequency, and the left vertical axis shows the cumulative value.
  • Figure 8 shows the results of observations made using a laser diffraction particle size distribution (PSD) measurement device.
  • PSD laser diffraction particle size distribution
  • Figure 8 shows the particle size distribution measured using a laser diffraction particle size distribution measurement device SALD-2300 manufactured by Shimadzu Corporation.
  • Particle size distribution is an index that shows what size (particle diameter) of particles is contained in the sample particle group to be measured and what the ratio (relative particle amount with the total being 100%) is, and the dimension (order) of the particle amount is based on volume.
  • aerogel granules have only one peak in relative particle amount with an average particle size of about 400 ⁇ m (bottom row of Figure 8).
  • the aerogel powder has an average particle size of about 90 ⁇ m
  • the aerogel fine powder has an average particle size of about 50 ⁇ m, but each has one peak in relative particle amount (third and second rows).
  • ultrafine aerogel particles have a first peak with an average particle size of about 20 ⁇ m and a second peak with an average particle size of about 0.3 ⁇ m, and the relative particle amount of the first peak with an average particle size of about 20 ⁇ m is 21.2%, and the second peak with an average particle size of about 0.3 ⁇ m is 78.8%.
  • the first peak with an average particle size of approximately 20 ⁇ m
  • the second peak with an average particle size of approximately 0.3 ⁇ m
  • the first peak is composed of fine particles with a three-dimensional mesh structure whose skeleton is made up of primary particles
  • the second peak with an average particle size of approximately 0.3 ⁇ m
  • General aerogel has a three-dimensional mesh structure whose skeleton is made up of secondary particles, so no matter how high the grinding conditions are, it is difficult to produce fine particles with a particle size of 10 ⁇ m or less.
  • it is necessary to fundamentally change the manufacturing method such as significantly changing not only the grinding conditions but also the aging conditions, unlike the normal aerogel manufacturing process.
  • the heat insulating fine particles 1 are preferably the aerogel ultrafine particles described above, that is, heat insulating fine particles made of aerogel having a three-dimensional mesh structure with a skeleton formed of clusters that are aggregates of primary particles 11, having a three-dimensional mesh structure with a skeleton formed of the primary particles, and having a mode of particle diameters of 0.1 ⁇ m to 1.0 ⁇ m for 50% or more of the volume.
  • silica fiber is preferable as the base fiber 6
  • PVA fiber is preferable as the binder fiber
  • PVA is preferable as the bonding agent.
  • silica fiber which is a typical base fiber 6, has a thickness of about 10 ⁇ m, so it is not a size relationship that allows aerogel granules of several hundred ⁇ m to be supported in the gaps of the base fiber, and aerogel ultrafine particles of 1 ⁇ m or less are preferable to form a structure that supports them in the gaps.
  • the thermal conductivity can be improved from approximately 40 mW/mK to less than 30 mW/mK by using ultrafine aerogel particles as the insulating particles 1.
  • the number of particles aligned in the thickness direction is small when the sheet is made thin, and the contribution of the shells of the particles to heat conduction is large
  • ultrafine aerogel particles have an extremely small particle diameter, so when the sheet is made thin, the gaps (voids) are larger than the particles in the thickness direction, and the heat conduction by the shells of the particles is small. Furthermore, the voids impede air convection, improving the insulating performance.
  • heat insulating sheet 100 it is preferable to adhere heat insulating particles 1 to the surface of the base fiber 6 with a binder 2. This imparts flame retardancy as well as heat insulating properties to the base fiber 6, and makes the entire heat insulating sheet 100 flame retardant.
  • FIG 3 is an explanatory diagram showing an example of the configuration of a flame-retardant fiber 200 (insulating fiber with added flame retardancy) formed by adhering insulating fine particles 1 to the surface of a base fiber 6. It is more reliable to form a flame-retardant layer 3 containing insulating fine particles 1 so as to cover the entire surface of the base fiber 6, but it has been found that the effect of increasing flame retardancy can be achieved even when the flame-retardant layer 3 is formed in islands as shown in Figure 3. For example, when ultrafine aerogel particles are used as the insulating fine particles 1, it is possible to add flame retardancy to the extent that the surface of the insulating sheet 100 will not burn even if it is heated with a high-temperature flame exceeding 1000°C. Details will be explained in embodiments 3 to 5 and the examples.
  • FIG. 4 is a flow chart showing an example of a method for manufacturing a heat insulating sheet according to one embodiment of the present invention.
  • the method for manufacturing the heat insulating sheet 100 includes the following steps:
  • “disperse (fine particles)” means to put the fine particles in a liquid (medium) and disperse them by stirring, not to dissolve them.
  • the heat insulating fine particles 1 are hydrophobic, they are dispersed in alcohol, and if they are hydrophilic, they are dispersed in water.
  • the heat insulating fine particles 1 are ultrafine aerogel particles whose surfaces are modified with trimethylsiloxy groups or other hydrophobic groups, they show strong hydrophobicity and have high affinity with alcohol (e.g., ethanol), so alcohol is preferably used as the medium in the first step (S1).
  • PVA powder is suitable as the binder.
  • Third step (S3) The insulating microparticle-containing suspension prepared in the first step (S1), the binder solution prepared in the second step (S2), base material fibers 6, and binder fibers 7 are mixed together to prepare a fiber-containing suspension.
  • the "sheeting" in the fourth step (S4) is a process similar to papermaking (a process in the manufacturing method of Japanese paper), in which liquid components are removed from the suspension and the solid components in the suspension are left in a thin film to form a sheet. More specifically, by passing the fiber-containing suspension in the third step (S3) through a liquid-permeable mesh, the liquid (medium) passes through and the matrix fibers 6 and binder fibers 7 remain on the mesh. The remaining matrix fibers 6 and binder fibers 7 are entangled with each other and are wet with a liquid containing heat insulating fine particles 1 and a binder.
  • the matrix fibers 6 are longer than the binder fibers 7 and spread along the mesh, while the binder fibers 7 are shorter and are sandwiched between the matrix fibers 6.
  • the matrix fibers 6 and binder fibers 7 are entangled and spread over the mesh, and the heat insulating fine particles 1 and binder solution are held in the gaps.
  • peeled off from the mesh it becomes a sheet.
  • the sheet is pressed vertically as is or multiple sheets are stacked together to squeeze out excess liquid, and then dried to produce a nonwoven fabric, i.e., the heat insulating sheet 100 of this embodiment 1.
  • the surfaces of the binder fibers 7 melt in part or in whole, forming a film that bonds with the adjacent base fibers 6.
  • the binder fibers 7 are PVA fibers, it is recommended to dry them at 65°C to 85°C.
  • the fiber-containing suspension prepared in the fourth step (S4) contains the binder solution from the second step (S2), so the binder continues to function even after drying, supporting the insulating microparticles 1 so that they do not fall out of the gaps between the base fibers 6.
  • This provides a method for manufacturing the insulating sheet 100 of embodiment 1.
  • the concentration of the insulating microparticles 1 in the first step (S1) is, for example, 0.1 to 0.5 wt%
  • the concentration of the polyvinyl alcohol in the second step (S2) is, for example, 0.075 g/dl
  • the contents of the base fibers 6 and binder fibers 7 in the fiber-containing suspension are, for example, 0.5 wt% and 0.025 wt%, respectively.
  • the content of insulating microparticles 1 in the suspension containing insulating microparticles should be as high as possible while still allowing uniform dispersion in the liquid.
  • the content of insulating microparticles 1 should be limited to the amount at which they do not aggregate, and an appropriate amount of medium should be added. If the amount of medium added is too small, the insulating microparticles 1 in the suspension will aggregate and form clusters, and will not disperse uniformly. On the other hand, if the amount of medium is too large, the content of insulating microparticles 1 per unit volume will decrease, so there is a trade-off. Optimize the design through experiments, etc.
  • the strength of the sheet for example the tensile strength, can be increased by increasing the content of matrix fibers 6. Also, the sheet can be further strengthened by increasing the content of binder fibers 7, but this comes at the expense of thermal insulation performance.
  • this flame-retardant fiber can be produced by bonding heat insulating fine particles 1 to the surface of the base fiber 6 with a binder. If this flame-retardant fiber is used as the base fiber in embodiments 1 and 2, flame retardancy can be imparted to the heat insulating sheet 100. In this case, ultrafine aerogel particles are particularly suitable as the heat insulating fine particles 1.
  • silica aerogel which is a high-purity silicon dioxide
  • the particles retain the flame retardancy of silica.
  • the diameter is about 8 ⁇ m to 12 ⁇ m
  • the particle diameter of conventional aerogel fine powder is several tens of ⁇ m to several hundreds of ⁇ m as explained with reference to FIG. 8, so that it cannot be bonded in such a manner that it adheres to the surface of the silica fiber.
  • the linear particle diameter of the aerogel ultrafine particles is mostly distributed in the range of 0.3 ⁇ m to 0.7 ⁇ m, so that it can be adhered to the surface of the silica fiber.
  • the flame retardant layer 3 containing the insulating fine particles 1 are more reliable to form the flame retardant layer 3 containing the insulating fine particles 1 so as to cover the entire surface of the matrix fiber 6, but the flame retardancy can also be increased by forming the flame retardant layer 3 in an island shape as shown in FIG. 3.
  • the insulating fine particles 1 are preferably aerogel ultrafine particles. However, this is not limited to this. Any fine particles that are flame retardant and have a particle size that is sufficiently smaller than the diameter of the base fiber will suffice.
  • FIG. 5 is a flow chart showing an example of a method for producing a flame-retardant fiber according to one embodiment of the present invention. A method for producing a flame-retardant fiber according to embodiment 3 will be described ...
  • the method for producing a flame-retardant fiber by vapor-depositing insulating microparticles 1 onto the surface of a base fiber 6 includes the following steps:
  • the binder is preferably, for example, PVA powder, which is added to water at room temperature, heated to about 80°C, stirred to dissolve, and then returned to room temperature.
  • the base fiber 6 may be in any form such as a sheet, blanket, pad, or cotton, or may be in a defibrated state.
  • the deposition in the fourth step (S14) is preferably ultrasonic deposition or heat deposition. This allows the insulating fine particles 1 to be adhered to the surface of the base fiber 6 more efficiently.
  • “more efficiently” means that a large amount of insulating fine particles 1 can be adhered with a small amount of consumption.
  • a step of spraying the slurry prepared in the third step (S13) or immersing the sheet-like or blanket-like base fiber 6 and then pulling it up and drying it can also be adopted.
  • the insulating fine particles exhibit strong hydrophobicity when their surfaces are modified with trimethylsiloxy groups or other hydrophobic groups, but have a high affinity for alcohol (e.g., ethanol), so ethanol was used as the medium in the first step (S1).
  • the fine particles can be any material other than ultrafine aerogel particles that exhibits heat resistance and hydrophobicity, and since hydrophobic fine particles generally have a high affinity for alcohol and can be uniformly dispersed, other heat-resistant hydrophobic fine particles and a suitable medium may be used instead.
  • the insulating fine particles (ultrafine aerogel particles) are hydrophilic, there is no need to use alcohol (ethanol), and water can be used as the medium in the first step (S1).
  • the mixing ratio of water, alcohol (e.g. ethanol), fine particles, and binder (e.g. PVA) in the prepared slurry is optimized through experiments etc. according to the desired specifications. For example, increasing the amount of PVA as a binder increases the adhesion of the fine particles but tends to decrease flame retardancy.
  • the method for producing a flame-retardant fiber in which insulating microparticles 1 are powdered onto the surface of the base fiber 6 includes the following steps:
  • a suitable binder is, for example, PVA powder.
  • the PVA powder is added to water at room temperature, heated to about 80°C, stirred to dissolve, and then returned to room temperature.
  • Mechanismally applying refers to mixing and stirring the heat insulating fine particles 1 while the surfaces of the base material fibers 6 are wet, i.e., while the evaporated binder solution is not yet dry, to cause the heat insulating fine particles 1 to adhere to the surfaces of the base material fibers 6 wet with the binder solution.
  • An alternative manufacturing method is provided for imparting flame retardancy to matrix fibers.
  • the flame-retardant fiber can be manufactured by either manufacturing method (a) in which the insulating fine particles 1 are vapor-deposited onto the surface of the base fiber 6, or manufacturing method (b) in which the insulating fine particles 1 are powdered onto the surface of the base fiber 6.
  • manufacturing method (a) in which the insulating fine particles 1 are vapor-deposited onto the surface of the base fiber 6, or manufacturing method (b) in which the insulating fine particles 1 are powdered onto the surface of the base fiber 6.
  • aerogel ultrafine particles are particularly suitable as the insulating fine particles 1 in this case.
  • a flame retardant layer 3 containing insulating fine particles 1 is formed on the surface of a matrix fiber 6.
  • the flame retardant layer 3 containing insulating fine particles 1 may be formed so as to cover the entire surface of the matrix fiber 6, but forming the flame retardant layer 3 in an island shape as shown in Fig. 3 also has the effect of enhancing flame retardancy.
  • This section describes a method for manufacturing a flame-retardant heat insulating sheet 100.
  • Figure 6 is a flow chart showing an example of a method for manufacturing a flame-retardant insulating sheet.
  • the following steps are carried out in order to construct a heat insulating sheet 100 similar to that described in the first and second embodiments, using flame-retardant fiber 200 as base fiber 6, which is manufactured by manufacturing method (a) of vapor-depositing heat insulating microparticles 1 on the surface of base fiber 6 shown in embodiment 4, or manufacturing method (b) of powdering heat insulating microparticles 1 on the surface of base fiber 6.
  • the suspension containing heat insulating particles may be the same as the suspension containing heat insulating particles prepared in the first step (S11), or the content of the heat insulating particles 1 may be optimized in consideration of the papermaking step (eleventh step, S24).
  • Tenth step (S23) The flame-retardant fiber 200, binder fiber 7, the second insulating microparticle-containing suspension for fibers prepared in the eighth step (S21), and the second binder solution for fibers prepared in the ninth step (S22) are mixed together to prepare a fiber-containing suspension.
  • the insulating microparticles 1 can be ultrafine aerogel particles
  • the matrix fibers 6 can be silica fibers
  • the binder can be polyvinyl alcohol.
  • the insulating sheet 100 can be constructed as in the first and second embodiments. As shown in the third embodiment, the flame-retardant layer 3 can be bonded to the base fiber 6 to obtain the flame-retardant fiber 200. Furthermore, by using this flame-retardant fiber as the base fiber 6, flame retardancy can be added to the insulating sheet 100. This makes it possible to realize an insulating sheet that is not only insulating but also heat-resistant and flame-retardant, and can withstand high-temperature flames of 1000°C or more. Such an insulating sheet can be used to shield adjacent battery cells or battery modules in a battery composed of a large number of accumulated battery cells, thereby preventing thermal runaway.
  • FIG. 11 Another embodiment of the heat insulating sheet according to the present invention will be described.
  • the difference from the heat insulating sheet 100 shown in FIG. 1 is that, as shown in FIG. 11, at least a part of the heat insulating fine particles 14 is embedded in the matrix fiber 300 constituting the heat insulating sheet.
  • the matrix fiber 300 is a fiber made of a thermoplastic resin 8, and the heat insulating fine particles 14 are mixed and present in the thermoplastic resin 8.
  • the heat insulating fine particles 14 may be present on the surface of the matrix fiber 300 with a part of the heat insulating fine particles 14 exposed from the thermoplastic resin 8.
  • the particle diameter of the heat insulating fine particles 14 is sufficiently smaller than the diameter of the matrix fiber 300, or when the amount of the heat insulating fine particles 14 is relatively small compared to the amount of the thermoplastic resin 8, the heat insulating fine particles 14 may be completely embedded in the thermoplastic resin 8 and no heat insulating fine particles 14 may be present on the surface of the matrix fiber 300.
  • Thermoplastic resins include, for example, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), aromatic polyesters mainly composed of polyalkylene terephthalate, aliphatic polyesters such as polylactic acid, polyesters such as polylactic acid, as well as known thermoplastic resins that can be used as materials for chemical fibers, such as polyamide, polyurethane, polyolefin, etc. These thermoplastic resins can be used alone or in a mixture of two or more types.
  • PET polyethylene terephthalate
  • PBT polybutylene terephthalate
  • aromatic polyesters mainly composed of polyalkylene terephthalate aromatic polyesters mainly composed of polyalkylene terephthalate
  • aliphatic polyesters such as polylactic acid
  • polyesters such as polylactic acid
  • thermoplastic resins that can be used as materials for chemical fibers, such as polyamide, polyurethane, polyolefin, etc.
  • thermoplastic resin made by remelting thermoplastic resin molded products such as PET bottles and molding them into pellets or powder may be used as the thermoplastic resin.
  • the heat insulating sheet of this embodiment is constructed by weaving and knitting threads spun from the base fiber 300.
  • the base fiber 300 can be spun by any known spinning method described below.
  • the yarns may also be woven or knitted in any known manner.
  • "woven” refers to weaving yarns to form a woven fabric, or knitting yarns to form a knitted fabric.
  • Woven fabrics include any known weaves, such as plain, twill, satin, amundsen, and double weave.
  • Knitted fabrics include any known knitted fabrics, such as jersey, smooth, half, and double raschel.
  • the insulating sheet of this embodiment is made by weaving and knitting yarn in which insulating particles 14 are mixed into the base fiber 300, so a highly insulating sheet can be obtained without the insulating particles 14 being supported by a binder.
  • the heat insulating sheet of this embodiment uses the same base material fiber as the base material fiber 300 shown in the above-mentioned embodiment 6. That is, the base material fiber contains a thermoplastic resin, the heat insulating fine particles are present in a state where at least a part of them is embedded in the thermoplastic resin of the base material fiber, and the sheet body is a heat insulating sheet formed by bonding the base material fibers to each other with a film formed by melting the thermoplastic resin.
  • the base fiber in this embodiment contains a thermoplastic resin and can be easily melted by heat, etc., so that the base fibers can be bonded together with a film made by melting the thermoplastic resin and formed into a sheet without using binder fibers. Also, as in embodiment 6, insulating fine particles are mixed into the base fiber, so a highly insulating sheet can be obtained without carrying the insulating fine particles with a binder.
  • the matrix fibers of this embodiment may be used as a substitute for the matrix fibers of embodiment 1 to produce an insulating sheet by the manufacturing method of embodiment 2. That is, fibers in which at least some of the insulating microparticles are embedded in a thermoplastic resin are used as the matrix fibers, and the insulating sheet is produced by a papermaking process using PVA fibers, a binder, and a suspension containing the insulating microparticles. Since the matrix fibers contain the insulating microparticles, higher insulating performance can be obtained.
  • the manufacturing method of this embodiment can also be cited as an example of a method for manufacturing the heat insulating sheets shown in the above-mentioned embodiments 6 and 7. As illustrated in FIG. 12, the manufacturing method of the heat insulating sheet of this embodiment includes the following steps.
  • Twelfth step (S25) A step of mixing a thermoplastic resin and heat insulating fine particles to obtain a fine particle-containing resin.
  • thermoplastic resin is heated and melted, and the insulating microparticles are added thereto, and the mixture is stirred and mixed while being heated to prepare a microparticle-containing resin.
  • the resin may then be crushed and placed in the container and melted again. This allows the insulating microparticles in the thermoplastic resin to be dispersed relatively uniformly.
  • the microparticle-containing resin may be obtained by placing the molten thermoplastic resin and the insulating microparticles together in a container or the like. In this case, the thermoplastic resin and the insulating microparticles are not completely mixed together to form the microparticle-containing resin.
  • step 13 the microparticle-containing resin 9 obtained in step 12 is placed in a container 400 with fine holes arranged in chamber C, and while the container 400 is heated, motor M is driven to rotate the container, causing the microparticle-containing resin 9 to be ejected from the fine holes in the container 400 by centrifugal force, and the resin is sprayed against the inner wall of chamber C to obtain short fibers.
  • the microparticle-containing resin may be obtained by directly putting the molten thermoplastic resin and the insulating microparticles together into the container with fine holes used in step 13. In this case, steps 12 and 13 are carried out simultaneously.
  • the container is connected to motor M by a rotating shaft 401, and is rotatable around the rotating shaft 401 by driving motor M.
  • the side wall of container 400 has a number of fine holes that connect the inside and outside of the container.
  • the container 400 is heated by heater H installed below to melt the microparticle-containing resin 9 inside, and in this state, motor M is driven to rotate it. Centrifugal force due to rotation acts on the microparticle-containing resin 9 inside container 400, and the microparticle-containing resin 9 is rapidly cooled and turned into fibers by being ejected from the fine holes in container 400, and is sprayed in the form of short fibers onto the inner wall of chamber C.
  • the short fibers sprayed onto the inner wall of chamber C become fibers (cotton-like fibers) 500 in which the short fibers are entangled with each other.
  • the obtained short fibers 500 are formed into a sheet. Since the short fibers contain a thermoplastic resin, they can be easily deformed by heating. Therefore, for example, the cotton-like fibers can be easily formed into a sheet by heating and forming them into a sheet. Alternatively, such short fibers can be spun by a known spinning method as in embodiment 6, and woven and knitted into yarn to form a sheet.
  • a manufacturing method of this embodiment can also be cited as an example of a method for manufacturing the heat insulating sheet shown in embodiment 6 above.
  • a manufacturing method of a heat insulating sheet according to yet another embodiment of the present invention includes the following steps, as illustrated in FIG. 14.
  • Step 15 can be performed in the same manner as step 12 of embodiment 8 (S25 in FIG. 12).
  • step 16 the molten microparticle-containing resin is extruded through the pores to obtain fibers.
  • Methods for obtaining fibers by extrusion include, for example, a method in which molten microparticle-containing resin 601 is extruded into a cooling atmosphere (by blowing cold air) using a spinning device 600 as shown in FIG. 15 to form multiple fibers, which are then twisted and spun (melt spinning method), a method in which microparticle-containing resin is extruded into a solidifying liquid rather than a cooling atmosphere (wet spinning method), and a method in which microparticle-containing resin is extruded into a heated atmosphere rather than a cooling atmosphere (dry spinning method).
  • Steps 17 and 18 can be carried out in the same manner as in embodiment 6.
  • Example 1 As explained in the fourth and fifth embodiments, ultrafine aerogel particles were adhered to glass wool, which is a silica fiber, to form a flame-retardant layer, and the flame-retardant layer was compared with glass wool that did not have a flame-retardant layer.
  • Samples of the same thickness were cut out from a single glass wool blanket to create a glass wool blanket sample without a flame-retardant layer and a glass wool blanket sample with a flame-retardant layer.
  • One side was heated with a Coleman mini torch 170-9105 for 60 seconds over a 1300°C flame, and the heated side and the opposite side were observed with the naked eye and an optical microscope.
  • Figure 9 is a photograph of the actual product.
  • the glass wool blanket sample without a flame-retardant layer has melted on the surface that was heated by the flame (hot side), and the opposite surface (cold side) has also been observed to have thinned in the center where it was heated.
  • the glass wool blanket sample with a flame-retardant layer has a dent observed on the surface that was heated by the flame (hot side), but there is no change on the opposite surface (cold side).
  • Figure 10 is an optical microscope photograph. It can be seen that the fibers have melted in the area of the glass wool blanket sample (left side) that does not form a flame-retardant layer, but the glass wool blanket sample (right side) that does form a flame-retardant layer shows almost no change from before it was heated by the flame.
  • Example 2 The staple fibers used in the method for producing a heat insulating sheet shown in embodiment 8 were produced by the following method. (Material amount) Cut pieces of PET bottles Ultrafine aerogel particles (product name: TIISA, manufactured by Thermalytica Inc.) (Method of producing fine particle-containing resin) The cut pieces of the PET bottle and ultrafine aerogel particles were placed in a stainless steel cup and stirred while being heated with an alcohol lamp until the pieces of the PET bottle were completely melted. Heating was then stopped and the mixture was cooled to room temperature to obtain a resin containing fine particles.
  • Ultrafine aerogel particles product name: TIISA, manufactured by Thermalytica Inc.
  • the content of ultrafine aerogel particles in the fine particle-containing resin was adjusted to 1 mass %, 3 mass %, 4 mass %, and as a control, no ultrafine aerogel particles (0 mass %).
  • the cooled fine particle-containing resin was hit with a hammer to break up lumps. (Method of Producing Short Fibers)
  • a small hole was drilled in the side of a 350 ml aluminum beverage bottle, and the bottle was set in the apparatus shown in Figure 16. The size of the small hole was 2 mm.
  • the present invention can be suitably used for heat insulating sheets and manufacturing methods thereof, heat insulating fibers and manufacturing methods thereof, and fiber-containing suspensions used in the manufacture of heat insulating sheets.
  • Heat insulating fine particles e.g., ultrafine aerogel particles
  • Binder e.g., PVA
  • Flame retardant layer Binder layer 6
  • Base fiber e.g., silica fiber
  • Binder fiber e.g., PVA fiber
  • Thermoplastic resin Microparticle-containing resin 11
  • Primary particle Secondary particle (aggregate of primary particles, cluster)
  • Aerogel fine powder (powder with a skeleton formed by secondary particles)
  • Fine particles whose skeleton is formed by primary particles e.g., ultrafine aerogel particles
  • 100 Heat insulating sheet 200 Flame retardant fiber 300
  • Flame retardant fiber 300
  • Base fiber e.g., silica fiber

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Textile Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Inorganic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Dispersion Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Chemical Or Physical Treatment Of Fibers (AREA)
  • Moulding By Coating Moulds (AREA)
  • Nonwoven Fabrics (AREA)
PCT/JP2024/002618 2023-01-31 2024-01-29 断熱シート及びその製造方法、断熱繊維及びその製造方法、並びに断熱シートの製造に用いられる繊維含有懸濁液 WO2024162246A1 (ja)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2024574882A JPWO2024162246A1 (enrdf_load_stackoverflow) 2023-01-31 2024-01-29

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2023-012552 2023-01-31
JP2023012552 2023-01-31

Publications (1)

Publication Number Publication Date
WO2024162246A1 true WO2024162246A1 (ja) 2024-08-08

Family

ID=92146730

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2024/002618 WO2024162246A1 (ja) 2023-01-31 2024-01-29 断熱シート及びその製造方法、断熱繊維及びその製造方法、並びに断熱シートの製造に用いられる繊維含有懸濁液

Country Status (3)

Country Link
JP (1) JPWO2024162246A1 (enrdf_load_stackoverflow)
TW (1) TW202438653A (enrdf_load_stackoverflow)
WO (1) WO2024162246A1 (enrdf_load_stackoverflow)

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003200534A (ja) * 2001-10-24 2003-07-15 Du Pont Mitsui Fluorochem Co Ltd フッ素樹脂積層体及びその製造方法
JP2004081382A (ja) * 2002-08-26 2004-03-18 Matsushita Electric Ind Co Ltd 断熱材とそれを用いた機器
JP2007514799A (ja) * 2003-10-21 2007-06-07 イー・アイ・デュポン・ドウ・ヌムール・アンド・カンパニー エチレンコポリマーで変性した配向ポリエステルのフィルム、テープ、繊維、および不織布
JP2008179932A (ja) * 2006-12-14 2008-08-07 Toray Ind Inc エレクトレット繊維シート
JP2013221231A (ja) * 2012-04-18 2013-10-28 Tec One Company 分岐型炭素繊維、分岐型炭素繊維製造方法、前記分岐型炭素繊維を有する材
JP2018179010A (ja) * 2017-04-03 2018-11-15 井前工業株式会社 耐火断熱シート
KR20200037989A (ko) * 2018-10-02 2020-04-10 이성윤 실리카 에어로겔 분말층으로 이루어진 단열성 및 내화성 포장재용 에어로겔 접착코팅제
JP2020200901A (ja) * 2019-06-11 2020-12-17 オゾンセーブ株式会社 断熱材および断絶材の製造方法
CN112341132A (zh) * 2020-11-06 2021-02-09 三棵树(上海)新材料研究有限公司 一种疏水性气凝胶水性浆料及其制备方法及应用
JP2021102822A (ja) * 2019-12-25 2021-07-15 日本バイリーン株式会社 繊維シートの製造方法
WO2022009845A1 (ja) * 2020-07-10 2022-01-13 株式会社巴川製紙所 難燃性シート
WO2022107365A1 (ja) * 2020-11-20 2022-05-27 国立研究開発法人物質・材料研究機構 エアロゲル粉末の製造方法及びこれを用いた断熱材

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6188245B2 (ja) * 2014-01-30 2017-08-30 オゾンセーブ株式会社 断熱材及び断熱材の製造方法

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003200534A (ja) * 2001-10-24 2003-07-15 Du Pont Mitsui Fluorochem Co Ltd フッ素樹脂積層体及びその製造方法
JP2004081382A (ja) * 2002-08-26 2004-03-18 Matsushita Electric Ind Co Ltd 断熱材とそれを用いた機器
JP2007514799A (ja) * 2003-10-21 2007-06-07 イー・アイ・デュポン・ドウ・ヌムール・アンド・カンパニー エチレンコポリマーで変性した配向ポリエステルのフィルム、テープ、繊維、および不織布
JP2008179932A (ja) * 2006-12-14 2008-08-07 Toray Ind Inc エレクトレット繊維シート
JP2013221231A (ja) * 2012-04-18 2013-10-28 Tec One Company 分岐型炭素繊維、分岐型炭素繊維製造方法、前記分岐型炭素繊維を有する材
JP2018179010A (ja) * 2017-04-03 2018-11-15 井前工業株式会社 耐火断熱シート
KR20200037989A (ko) * 2018-10-02 2020-04-10 이성윤 실리카 에어로겔 분말층으로 이루어진 단열성 및 내화성 포장재용 에어로겔 접착코팅제
JP2020200901A (ja) * 2019-06-11 2020-12-17 オゾンセーブ株式会社 断熱材および断絶材の製造方法
JP2021102822A (ja) * 2019-12-25 2021-07-15 日本バイリーン株式会社 繊維シートの製造方法
WO2022009845A1 (ja) * 2020-07-10 2022-01-13 株式会社巴川製紙所 難燃性シート
CN112341132A (zh) * 2020-11-06 2021-02-09 三棵树(上海)新材料研究有限公司 一种疏水性气凝胶水性浆料及其制备方法及应用
WO2022107365A1 (ja) * 2020-11-20 2022-05-27 国立研究開発法人物質・材料研究機構 エアロゲル粉末の製造方法及びこれを用いた断熱材

Also Published As

Publication number Publication date
JPWO2024162246A1 (enrdf_load_stackoverflow) 2024-08-08
TW202438653A (zh) 2024-10-01

Similar Documents

Publication Publication Date Title
US11370195B2 (en) Multilayer composite and method for producing same
Greiner et al. Functional self-assembled nanofibers by electrospinning
KR102422642B1 (ko) 에어로겔 및 폴리머 물질을 함유하는 합성 섬유, 및 이의 제조 방법 및 이를 포함하는 물품
JP5239134B2 (ja) 繊維分散体からなるスポンジ状構造体およびその製造方法
Wu et al. Ultraflexible, breathable, and form-stable phase change fibrous membranes by green electrospinning for personal thermal management
CN100491620C (zh) 一种功能微粒改性熔喷非织造布的制备方法及制造设备
CN1320180C (zh) 聚酯型常产纤维及其含有该纤维的无纺布
CN1097116C (zh) 多孔性纤维结构体及其制造方法
CN111455484A (zh) 一种高掺杂辐射制冷复合纤维及其织物的制备方法
KR20110097252A (ko) 단열성 나노분말이 단열체로부터 분리되지 않는 단열체 및 그 단열체의 제조방법
KR100297473B1 (ko) 원적외선을방사하는부직포및그제조방법
CN112981712B (zh) 一种纤维复合保暖絮片及其制备方法
BRPI0910442B1 (pt) material não-tecido para uso como telha (acústica) de teto e sua composição
JP2001524613A (ja) 繊維状パックを製造する方法
BRPI0612648A2 (pt) esteira de polìmero/wucs e método de formação da mesma
CN114507987B (zh) 一种垂直纤维阵列改性涂层织物及其制备方法
WO2024162246A1 (ja) 断熱シート及びその製造方法、断熱繊維及びその製造方法、並びに断熱シートの製造に用いられる繊維含有懸濁液
EP3006610B1 (en) Organic resin non-crimped staple fiber
CN120641689A (zh) 隔热片材及其制造方法、隔热纤维及其制造方法、和隔热片材的制造所使用的含有纤维的悬浮液
CN109056106A (zh) 一种热稳定、高强度定型相变超细纤维的制备方法
JP4178997B2 (ja) 機能性繊維集合体及びそれを用いた成形体
JP4736548B2 (ja) 液晶性樹脂繊維からなる不織布
JPH02255735A (ja) シート状強化繊維複合体
Yang et al. Review on the preparation methods and the research hot spots and development of phase change fibers based on thermoregulation
JP2022139215A (ja) 断熱構造体

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 24750195

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2024574882

Country of ref document: JP