JP5756362B2 - Solid particle fusion fiber and method for producing solid particle fusion fiber sheet - Google Patents

Description

  The present invention relates to a solid particle fusion fiber and a method for producing a solid particle fusion fiber sheet.

  As a method for producing a fiber carrying solid particles on the surface of a thermoplastic fiber, Patent Document 1 discloses that solid particles having a melting point or decomposition temperature higher than the melting point of the thermoplastic resin are made higher than the melting point of the thermoplastic resin. Heated solid particles are brought into contact with the fibers while being maintained at a temperature higher than the melting point of the thermoplastic resin, and the solid particles are supported on the fiber surface by fusing the fiber surface to form solid particle fused fibers. A method for producing a solid particle-supporting fiber is disclosed, wherein the solid particle fusion fiber is cooled to fix the solid particle on the fiber surface.

  The solid particle-carrying fiber obtained by this production method is compared with the solid particle-carrying fiber obtained by the prior art in which the surface of the thermoplastic fiber is previously melted and the solid particles are fused to the molten thermoplastic fiber. Since the solid particles are not buried in the thermoplastic resin layer on the fiber surface, the solid particles have an effect of being uniformly fixed while maintaining the surface characteristics of the solid particles effectively. However, since the fusion with the heated solid particles is performed instantaneously, the fusion may be insufficient or the amount of fixing may be insufficient. Moreover, when it was requested | required that a solid particle carrying fiber or a solid particle carrying fiber sheet should have several functionality, there existed a problem that the request could not be answered.

JP 2004-3070 A

  In the solid particle fusion fiber or solid particle fusion fiber sheet in which solid particles are fused on the surface of a thermoplastic fiber, the present invention solves the above problems, and further improves the functionality of the solid particle fusion fiber and the solid. It is an object to provide a particle-fused fiber sheet.

In order to solve the above-mentioned problem, in the invention according to claim 1, at least the surface of a thermoplastic fiber comprising a thermoplastic resin, the solid particles A and the solid particles having a melting point or decomposition temperature higher than the melting point of the thermoplastic resin A method for producing a solid-particle fused fiber for fusing B, wherein the solid particle A heated to a temperature higher than the melting point of the thermoplastic resin is brought into contact with the surface of the thermoplastic fiber, and the thermoplastic resin causes the The solid particles A are fused to form a solid particle fused fiber precursor, and then the solid particles B are heated to a temperature higher than the melting point of the thermoplastic resin and the solid particles A have a large particle size. The solid particle fusion fiber manufacturing method is characterized by contacting the surface of the solid particle fusion fiber precursor and fusing the solid particles B with the thermoplastic resin. In the invention according to claim 1, when the particle diameter of the solid particles A is larger than the particle diameter of the solid particles B, the solid particles A and the solid particles are fused by first fusing the solid particles A having a large particle diameter. There is an effect that the amount of fusion of the solid particles A can be increased as compared with the case where the particle mixture obtained by mixing the particles B is fused.

The invention according to claim 2 is the above-described method for producing a solid particle fused fiber, wherein the solid particles A are polytetrafluoroethylene particles, and the solid particles B are carbon black. .

In the invention which concerns on Claim 3 , the solid particle which has melting | fusing point higher than the melting | fusing point of the said thermoplastic resin, or decomposition | disassembly temperature on the surface of the said thermoplastic fiber of the thermoplastic fiber sheet containing the thermoplastic fiber which the surface consists of a thermoplastic resin at least A method for producing a solid particle fusion fiber sheet for fusing A and solid particles B, wherein the solid particle A heated to a temperature higher than the melting point of the thermoplastic resin is brought into contact with the thermoplastic fiber sheet, and the heat The solid particles A are fused with a plastic resin to form a solid particle fused fiber sheet precursor, and then heated to a temperature higher than the melting point of the thermoplastic resin , and the solid particles A have a large particle size. The solid particle fusion fiber, wherein the solid particle B is brought into contact with the solid particle fusion fiber sheet precursor and the solid particle B is fused with the thermoplastic resin. It is a method of manufacturing the over door.

The invention according to claim 4 is the above-described method for producing a solid particle fused fiber sheet, wherein the solid particles A are polytetrafluoroethylene particles, and the solid particles B are carbon black. Yes.

  According to the present invention, a solid particle fused fiber or a solid particle fused fiber sheet in which solid particles are fused on the surface of a thermoplastic fiber, and a solid particle fused fiber and a solid particle fused fiber sheet with higher functionality are provided. It became possible to do.

It is a block diagram which shows typically an example of the manufacturing apparatus of the solid particle fusion fiber or solid particle fusion fiber sheet used with the manufacturing method of this invention. It is the schematic which shows typically another example of the manufacturing apparatus of the solid particle fusion fiber or solid particle fusion fiber sheet used with the manufacturing method of this invention.

  Hereinafter, an embodiment of a method for producing a solid particle fusion fiber or a solid particle fusion fiber sheet according to the present invention will be described in detail.

  In the method for producing a solid particle fusion fiber according to the present invention, a solid particle A and a solid particle B having a melting point or decomposition temperature higher than the melting point of the thermoplastic resin are formed on the surface of a thermoplastic fiber having at least a surface made of a thermoplastic resin. A method for producing a solid particle fusion fiber to be fused, wherein the solid particle A heated to a temperature higher than the melting point of the thermoplastic resin is brought into contact with the surface of the thermoplastic fiber, and the solid particle is produced by the thermoplastic resin. A is fused to form a solid particle fused fiber precursor, and then the solid particle B heated to a temperature higher than the melting point of the thermoplastic resin is brought into contact with the surface of the solid particle fused fiber precursor. The solid particles B are fused with the thermoplastic resin.

  Further, the method for producing a solid particle fusion fiber sheet according to the present invention has a melting point higher than the melting point of the thermoplastic resin on the surface of the thermoplastic fiber of the thermoplastic fiber sheet including a thermoplastic fiber having at least a surface made of a thermoplastic resin. Alternatively, a method for producing a solid particle fusion fiber sheet in which the solid particles A and the solid particles B having a decomposition temperature are fused, wherein the solid particles A heated to a temperature higher than the melting point of the thermoplastic resin are the thermoplastic fibers. The solid particles B are brought into contact with a sheet, the solid particles A are fused by the thermoplastic resin to form a solid particle fused fiber sheet precursor, and then the solid particles B heated to a temperature higher than the melting point of the thermoplastic resin. The solid particle B is brought into contact with the solid particle fused fiber sheet precursor, and the solid particles B are fused with the thermoplastic resin.

  At least the surface of the thermoplastic fiber used in the method for producing a solid particle fused fiber of the present invention or the thermoplastic fiber contained in the fiber sheet used in the method for producing a solid particle fused fiber sheet of the present invention is thermoplastic. As long as it is a fiber made of a resin and the fiber surface is melted by heating (for example, heating at 50 ° C. or higher, preferably heating at 80 ° C. or higher), the type of the fiber can be appropriately selected. Examples of such fibers include a melt spinning method, a dry spinning method, a wet spinning method, a direct spinning method (spun bond method, melt blow method, flash spinning method, antistatic method, spinning stock solution and gas flow in parallel. And spinning (for example, Japanese Patent Application Laid-Open No. 2009-287138), a method of extracting a fiber having a small fiber diameter by removing one or more types of resin components from a composite fiber, It can be obtained by a known method such as a method for obtaining a fresh fiber.

  Further, the cross-sectional shape of the thermoplastic fiber can be appropriately selected from known forms such as an alphabet, a polygon, a round, an ellipse, a semicircle, and a star. When the thermoplastic fiber is a composite fiber, a core-sheath type, a side-by-side type, a sea-island type, an orange-type, and the like are possible as the mode, and a core-sheath type and a side-by-side type are particularly preferable.

  Examples of the fiber obtained by the melt spinning method or the direct spinning method include synthetic fibers made of a thermoplastic resin (for example, polyolefin, polyester, polyamide, etc.), and the synthetic fiber includes one kind of heat. Even a synthetic fiber made of a plastic resin or a composite fiber in which two or more different types of resins are combined can be appropriately selected and used. Examples of such composite fibers include composite fibers in which two or more kinds of resins having different melting points are combined, such as copolymer polyester / polyester, copolymer polypropylene / polypropylene, polypropylene / polyamide, polyethylene / polypropylene, Mention may be made of composite fibers made of a combination of resins such as polypropylene / polyester or polyethylene / polyester. Further, when the composite fiber is a core-sheath type composite fiber having a high melting point resin in the core and a low melting point resin in the sheath, the solid particles are fused when the solid particles are fused to the surface of the thermoplastic fiber. Since shrinkage and thread breakage are less likely to occur, this is preferable. In the present invention, the melting point is determined using a differential scanning calorimeter in accordance with JIS K 7121-1987.

  Further, the thermoplastic fiber has a sheath part on the surface of a fiber such as a rayon fiber, an acetate fiber, a wool fiber, or a carbon fiber such that the core part does not have a melting point and has a decomposition temperature, for example, A fiber to which a thermoplastic resin is applied by, for example, coating or powder coating is also applicable. Further, the thermoplastic fiber is a fiber having a high melting point, such as a fiber having a high melting point, for example, a glass fiber, a ceramic fiber, or a metal fiber, as a sheath part, a thermoplastic resin, For example, fibers applied by coating or powder coating can also be applied.

  The thermoplastic fiber may be a fiber made of one or more thermoplastic resins on the surface, and the thermoplastic resin is 50 mass% or more, preferably 60 mass, with respect to the constituent resin on the fiber surface. % Or more, more preferably 70 mass% or more, and particularly preferably 90 mass% or more.

  The average fiber diameter of the thermoplastic fiber is not particularly limited as long as the solid particles can be fused, and can be in the range of 0.1 to 150 μm, preferably in the range of 0.5 to 100 μm, and more Preferably it is the range of 1-70 micrometers. Here, the average fiber diameter means an average value of fiber diameters determined from the cross-sectional shape of each fiber by measuring 500 fibers. When the cross-sectional shape of the fiber is a circle, the diameter of the fiber cross-section is When the cross-sectional shape of the fiber is other than a circle, the diameter of a circle having the same area as the cross-sectional area of the fiber is used as the fiber diameter.

  The thermoplastic fiber sheet used in the method for producing a solid particle fusion fiber sheet of the present invention is not particularly limited as long as it is a fiber sheet having the thermoplastic fiber in the fiber sheet. The sheet can contain only the thermoplastic fibers or can contain fibers other than the thermoplastic fibers. The fiber other than the thermoplastic fiber (that is, the fiber having at least the surface made of a thermoplastic resin) is not particularly limited, and the surface is not a thermoplastic resin, for example, an inorganic fiber, or has no melting point and decomposes. A fiber having a temperature can be used. The ratio of the thermoplastic fiber contained in the thermoplastic fiber sheet is preferably 30% or more, more preferably 50% or more, and further preferably 70% or more.

  Examples of the structure of the thermoplastic fiber sheet include fabrics such as woven fabrics, knitted fabrics, and nonwoven fabrics, or combinations thereof. In the case of a woven fabric or a knitted fabric, for example, it can be obtained by processing the thermoplastic fiber with a loom or a knitting machine. In the case where the thermoplastic fiber sheet is a nonwoven fabric, for example, a conventional nonwoven fabric manufacturing method, a dry method, a wet method, a direct spinning method (spunbond method, melt blow method, flash spinning method, antistatic method, A nonwoven fabric produced by a spinning method (for example, Japanese Patent Application Laid-Open No. 2009-287138) and the like which are spun by discharging a spinning solution and a gas flow in parallel can be applied. In addition, the non-woven fabric formed by these manufacturing methods was mixed with adhesive fibers or composite fibers in which two or more kinds of resins having different melting points were mixed in advance, and then the fibers were joined by heat treatment. It can be set as a thermoplastic fiber sheet. Moreover, it can also be set as the thermoplastic fiber sheet which entangled the said nonwoven fabric by mechanical entanglement process (for example, water flow entanglement or needle punch etc.). In addition, by providing the nonwoven fabric between smooth rolls, between uneven rolls, or between a smooth roll and uneven rolls, heat that is partially heat-bonded or thickness-adjusted It can also be a plastic fiber sheet. Moreover, it can also be set as the thermoplastic fiber sheet formed by laminating | stacking the said thermoplastic fiber sheet from which a kind differs, and further integrating.

  Further, the appearance of the thermoplastic fiber sheet is not particularly limited. For example, the thermoplastic fiber sheet has a long shape (for example, a fiber sheet wound around a roll) or a non-long shape (that is, the long fiber sheet). Fiber sheet that can be obtained by cutting).

The surface density, thickness, porosity and other properties of the thermoplastic fiber sheet are not particularly limited, but the surface density is preferably ² to 500 g / m ² , and 3 to 400 g / m. ² is more preferable, and 5-300 g / m ² is even more preferable. The thickness is preferably 0.01 to 30 mm, more preferably 0.02 to 25 mm, and still more preferably 0.03 to 20 mm. In the present invention, the thickness is an arithmetic average of thicknesses of 5 points measured with a thickness measuring instrument (dial thickness gauge 0.01 mm type H model, manufactured by Ozaki Mfg. Co., Ltd.) for thicknesses of 5 mm or less. Apply the value. When the thickness exceeds 5 mm, the thickness measured under a load of 0.5 g / cm ² is applied. When the evaluation is performed by both methods, the thickness value obtained by the former thickness measuring device is used. The porosity is preferably 30 to 99%, more preferably 50 to 95%, and still more preferably 70 to 90%. In the present invention, the porosity means the abundance ratio of the voids to the total volume of the thermoplastic fiber sheet, and is a value obtained by [1- (area density / thickness) / specific gravity] × 100 (area density). g / m ² , thickness μm, specific gravity g / cm ³ ).

  The solid particles A and the solid particles B (hereinafter sometimes simply referred to as solid particles) used in the method for producing solid particle fused fibers or the method for producing solid particle fused fiber sheets according to the present invention are solid particles. As long as it is a solid particle having a melting point or decomposition temperature higher than the melting point of the thermoplastic resin constituting the surface of the thermoplastic fiber used for fusing the resin, it can be either inorganic or organic. The solid particles B can be the same particles as the solid particles A or different particles. The same means that the material, composition and particle size distribution are the same. Examples of the material of such solid particles include silicon carbide, activated carbon, zeolite, carbon particles, tourmaline, calcium carbonate, metal particles, and metal oxide particles such as titanium oxide, water-absorbing resin, ion-exchange resin, and repellent material. Various materials such as a functional resin such as an aqueous resin can be applied. Examples of the solid particles include deodorization, gas removal, catalyst, water absorption, ion exchange, electromagnetic wave radiation, heat radiation, heat absorption, ion generation, conduction, insulation, antibacterial, flame retardant, electromagnetic wave shielding, soundproofing, and water / oil repellent. If the solid particles having the above functionality are applied, the function can be effectively exhibited on the fiber surface.

  The melting point or decomposition temperature of the solid particles must be higher than the melting point of the resin having the lowest melting point among the thermoplastic resins constituting the surface of the thermoplastic fiber, and if the melting point or decomposition temperature of the solid particles is When the melting point is lower than the melting point of the resin having the lowest melting point, the surface of the thermoplastic fiber is not melted by the heat of the heated solid particles, and the solid particles are not fused to the surface of the thermoplastic fiber. That is, even if solid particles are not fused to the surface of the thermoplastic fiber, or solid particles are fused to the surface of the thermoplastic fiber, the solid particles are melted before the fiber surface and the solid particles are Aggregates or solid particles and the fiber surface are fused in a wide area, and the effective area of the fused solid particles is small.

  When the particle diameter at the 50% cumulative height in the particle diameter distribution of the solid particles is defined as a particle diameter D50, the particle diameter D50 is preferably equal to or less than the average fiber diameter of the thermoplastic fibers. When the particle diameter D50 of the solid particles exceeds the average fiber diameter, the solid particles are likely to drop off from the surface of the thermoplastic fiber, and it may be difficult to keep the solid particles fused to the fiber surface. Moreover, even if it is intended to obtain a fiber in which such solid particles are fused, it may be difficult to fuse the solid particles to the fiber surface. In this invention, it is preferable that the particle diameter D50 of a solid particle is 3/4 or less of the average fiber diameter of the said thermoplastic fiber, and it is more preferable that it is 3/5 or less. The particle diameter D50 of the solid particles is preferably 0.1 μm or more, more preferably 0.5 μm or more, and further preferably 1 μm or more. Moreover, it can be 150 micrometers or less, 100 micrometers or less are preferable, 50 micrometers or less are more preferable, and 30 micrometers or less are still more preferable. The value of the particle size D50 at the 50% cumulative height in the particle size distribution of the solid particles is determined by a dry method using a laser diffraction / scattering type particle size distribution analyzer (LMS-30 manufactured by Seishin Enterprise Co., Ltd.). It can be determined by measuring 500 or more solid particles as solid particles as primary particles or as solid particles as secondary particles.

  In the first step of the method for producing a solid particle fusion fiber according to the present invention, the solid particle A heated to a temperature higher than the melting point of the thermoplastic resin on the surface of the thermoplastic fiber is brought into contact with the surface of the thermoplastic fiber, The solid particles A are fused with a thermoplastic resin to form a solid particle fused fiber precursor. In the first step of the method for producing a solid particle fused fiber sheet according to the present invention, the solid particles A heated to a temperature higher than the melting point of the thermoplastic resin on the surface of the thermoplastic fibers contained in the thermoplastic fiber sheet are heated. The solid particle A is brought into contact with a plastic fiber sheet, and the solid particles A are fused with the thermoplastic resin to form a solid particle fused fiber sheet precursor.

In the method of bringing the heated solid particles A heated to a temperature higher than the melting point of the thermoplastic resin into contact with the thermoplastic fiber or the thermoplastic fiber sheet, the solid particles A can be fused to the surface of the thermoplastic fiber by the contact. As long as it is not particularly limited, for example,
(1A) A method of spraying an air stream containing heated solid particles A onto a thermoplastic fiber surface or a thermoplastic fiber sheet;
(2A) A method of allowing the heated solid particles A to spontaneously fall on the thermoplastic fiber or thermoplastic fiber sheet;
(3A) A method of shaking a heat-resistant container charged with heated solid particles A and thermoplastic fibers or thermoplastic fiber sheets;
(4A) A method of immersing a thermoplastic fiber or a thermoplastic fiber sheet in the heated solid particles A;
(5A) A method of exposing a thermoplastic fiber or a thermoplastic fiber sheet to the fluidized bed of the heated solid particles A can be exemplified.

  As a method of bringing the heated solid particles A into contact with the thermoplastic fiber or the thermoplastic fiber sheet, the contact method (1A), that is, a method of blowing an air stream containing the heated solid particles A onto the surface of the thermoplastic fiber or the thermoplastic fiber sheet. When used, a mixed gas stream in which the solid particles A heated above the melting point of the thermoplastic resin having the lowest melting point among the thermoplastic resins constituting the surface of the thermoplastic fiber and an air stream is used is used. In order to employ such a contact method (1A), it is preferable to use the manufacturing apparatus illustrated in FIG. 1 or FIG.

  FIG. 1 is a block diagram schematically showing an example of an apparatus used in the production method of the present invention, in which a thermoplastic fiber 80 is used as an object to be processed, and the thermoplastic fiber 80 is supported as an object support means. By using the fiber support means 70 that can be used, it can be used as an apparatus for producing solid particle fusion fibers according to the present invention. Further, according to the present invention, the thermoplastic fiber sheet 80 ′ is used as an object to be processed, and the fiber sheet support means 70 ′ capable of supporting the thermoplastic fiber sheet 80 ′ is used as an object support means. It can be used as an apparatus for producing a solid particle fused fiber sheet.

  The manufacturing apparatus shown in FIG. 1 is connected to the airflow generating means 10 for generating an airflow; the particle supplying means 20 for supplying solid particles; and the airflow generating means 10 and the particle supplying means 20, respectively. The air flow generated by 10 is fed in, and the solid particles are supplied into the sent air flow by the particle supply means 20, thereby mixing the air flow and the solid particles to form a mixed air flow. A particle mixing means 30 capable of communicating with the particle mixing means 30 and an ejection means 40 for ejecting an air flow containing solid particles formed by the particle forming means 30; the air flow generation means 10 and the particle supply means 20; Heating means 50, 51, 52, 53 provided on the particle mixing means 30 and the ejection means 40, respectively; and the ejection means 4 Fiber support means 70 (which can hold the thermoplastic fiber 80 (or the thermoplastic fiber sheet 80 ′) at a position where the solid particle-containing air stream ejected from the surface can contact the surface of the thermoplastic fiber (or the thermoplastic fiber sheet). Or fiber sheet support means 70 ').

  In the manufacturing method according to the present invention, it is more preferable to use the apparatus shown in FIG. FIG. 2 is a schematic view schematically showing an example of an apparatus used in the production method of the present invention. Similar to the embodiment shown in FIG. 1, a thermoplastic fiber 80 is used as an object to be processed, and the object support means. As described above, by using the fiber support means 70 capable of supporting the thermoplastic fiber 80, it can be used as a solid particle fusion fiber manufacturing apparatus according to the present invention. Further, by using the thermoplastic fiber sheet 80 ′ as the object to be processed and the fiber sheet supporting means 70 ′ or 71 capable of supporting the thermoplastic fiber sheet 80 ′ as the object to be processed, It can be used as an apparatus for producing a solid particle fused fiber sheet according to the invention.

As described above, in the case of using the contact method (1A), that is, the method of spraying an air stream containing the heated solid particles A on the surface of the thermoplastic fiber or the thermoplastic fiber sheet, the thermoplastic constituting the surface of the thermoplastic fiber. Among the resins, a mixed air stream in which the solid particles A heated to the melting point of the thermoplastic resin having the lowest melting point and an air stream is mixed is used. To prepare such a mixed airflow, for example,
(A) A method of supplying solid particles heated to a melting point or higher of a thermoplastic resin in an air flow;
(B) a method of supplying solid particles in an air current heated to a temperature equal to or higher than the melting point of the thermoplastic resin; or
(C) A method in which a solid particle is supplied in an air stream is heated to a temperature higher than the melting point of the thermoplastic resin. Among these, according to the mixed airflow preparation method (b) or (c), the solid particles are heated above the melting point of the thermoplastic resin through the airflow heated above the melting point of the thermoplastic resin.

  In the production method of the present invention, it is necessary to heat the solid particles to a temperature higher than the melting point of the thermoplastic resin. If the excessively high temperature solid particles are fused to the thermoplastic fiber, the yarn of the thermoplastic fiber When there is a problem of cutting or shrinking, it is preferable to heat to a temperature not exceeding 100 ° C higher than the melting point of the thermoplastic resin, and to a temperature not exceeding 50 ° C higher than the melting point of the thermoplastic resin. More preferably.

  In the mixed airflow preparation method (a), a method of supplying solid particles heated to a temperature equal to or higher than the melting point of the thermoplastic resin to an airflow heated to a temperature equal to or higher than 50 ° C. lower than the melting point of the thermoplastic resin is preferable. In this case, when the airflow and the solid particles are mixed, there is an effect of preheating so that the temperature of the solid particles does not become lower than the melting point of the thermoplastic resin. Further, there is an effect of keeping the temperature of the solid particles so that the temperature of the solid particles does not become lower than the melting point of the thermoplastic resin before the heated solid particles collide with the fiber. If there is a problem that when a mixed airflow of airflow and solid particles is blown onto the fiber, an excessively high temperature airflow hits the fiber, causing fiber breakage or shrinkage, the melting point of the thermoplastic resin It is preferable that the air stream is heated to a temperature equal to or higher than a temperature lower by 50 ° C. and is heated to a temperature lower than the temperature of the heated solid particles A.

  In each of the mixed airflow preparation methods (a), (b), or (c) described above, the mixed airflow after the airflow and the solid particles are mixed, if necessary, may be a thermoplastic resin. It is preferable to heat above the melting point. In this case, there is an effect of keeping the temperature of the solid particles so as not to be lower than the melting point of the thermoplastic resin before the solid particles collide with the thermoplastic fiber.

  In order to obtain a heated airflow, for example, as shown in FIG. 1, an airflow is generated by an airflow generating means 10 (for example, a blower or a compressor), and then a predetermined temperature (for example, a thermoplastic resin) is generated by a known heating means. A method of heating the airflow to a temperature of 50 ° C. lower than the melting point or a temperature higher than the melting point of the thermoplastic resin can be used. In order to obtain heated solid particles, for example, a heater 51 is attached inside and outside the solid particle supply means 20 (for example, a hopper or a supply container), and the solid particles in the solid particle supply means 20 are kept at a predetermined temperature (for example, A temperature of 50 ° C. lower than the melting point of the thermoplastic resin, or a temperature higher than the melting point of the thermoplastic resin), or a fluidized bed dryer generally used as a powder dryer A method of heating solid particles to a predetermined temperature (for example, a temperature of 50 ° C. lower than the melting point of the thermoplastic resin or a temperature higher than the melting point of the thermoplastic resin) using an apparatus can be used.

  As a method of preparing a mixed air flow by supplying solid particles to an air flow, for example, a method of supplying solid particles from the solid particle supply means 20 (for example, a hopper or a supply container) into the air flow by a certain amount, or a flow After heating solid particles to a temperature equal to or higher than the melting point of the thermoplastic resin using a device such as a layer dryer, a mixed gas in which the solid particles heated in the gas from the fluidized bed dryer are dispersed and mixed is used. The method of taking out and supplying this mixed gas to an airflow can be mentioned.

  In addition to these methods, for example, as shown in FIG. 2, the particle mixing means 30 is an ejector, and the air flow A generated by the blower 11 and the heating tube 12 as the air flow generating means is supplied to the particle mixing means 30. The feed and particle mixing means 30 is connected to a supply container 21 as a particle supply means and a rotary supply control rotor 23 provided at the bottom thereof, and is supplied from the particle supply means by the suction force generated by the airflow A. It is also possible to use a method of sucking the solid particles 29 to be supplied and supplying the solid particles into the airflow. In this case, in the particle mixing means 30, if the cross-sectional area of the air flow C of the portion 31 to which the particles are supplied is made smaller than the cross-sectional area before and after that to speed up the air flow, the suction force works strongly and the solid particles are dispersed. The mixing effect can be increased.

  As described above, in order to spray the air stream containing the heated solid particles A onto the surface of the thermoplastic fiber or the thermoplastic fiber sheet, the mixed air stream obtained as described above (that is, the thermoplastic constituting the surface of the thermoplastic fiber). Among the resins, a mixed gas stream containing solid particles A heated to a temperature equal to or higher than the melting point of the thermoplastic resin having the lowest melting point is sprayed on the surface of the thermoplastic fiber or the thermoplastic fiber sheet. Prior to spraying, the temperature of the thermoplastic fiber surface or the thermoplastic fiber sheet is preferably less than the melting point of the thermoplastic resin and the temperature difference with the melting point is within 20 ° C.

  As a method of spraying on the surface of the thermoplastic fiber or the thermoplastic fiber sheet, for example, as illustrated in FIG. 2, when a mixed air flow containing solid particles is ejected from the nozzle 41 as the ejection means, the solid particles are ejected at the time of ejection. It collides with the surface of the thermoplastic fiber by the inertial force due to the given kinetic energy. The ejection means can be connected directly to the particle mixing means 30 or can be connected via a connecting pipe, for example. The nozzle may have a shape suitable for ejecting fluid. For example, the flow path can be narrowed to increase the inertial force of the solid particles, or the nozzle tip can be widened to widen the ejection angle of the solid particles. It is also preferable to use a nozzle material that is less likely to be worn or the like depending on the solid particles ejected from the nozzle.

  Moreover, as illustrated in FIG. 1 or FIG. 2, it is preferable to blow an air stream containing heated solid particles on the thermoplastic fiber or thermoplastic fiber sheet supported by the movable fiber support means or fiber sheet support means. Preferable examples of such support means include, for example, a rotating roll 70 (or 70 ′) on which thermoplastic fibers or a thermoplastic fiber sheet is placed before and after a treatment region in which an air stream containing heated solid particles is blown, thermoplasticity Tenter-type device that moves while gripping both sides of fiber or thermoplastic fiber sheet with pins or grips, pair roll that supports thermoplastic fiber or thermoplastic fiber sheet, or thermoplastic fiber or thermoplastic fiber sheet An opening support body (for example, conveyor net 71 etc.) that can be sprayed while being loaded can be mentioned. In addition, according to a conveyor net etc., a several thermoplastic fiber can also be supported simultaneously.

  Moreover, in order to spray uniformly in the width direction of a thermoplastic fiber or a thermoplastic fiber sheet, it is also possible to install a plurality of jetting means for airflow containing heated solid particles, or to provide a plurality of nozzle holes provided in the jetting means. Is also possible. Moreover, it is also possible to make the nozzle hole into a slit shape and to have a shape in which the tip of the nozzle is expanded to the entire width of the thermoplastic fiber sheet. Further, if the ejecting means is capable of reciprocating movement substantially parallel to the width direction of the thermoplastic fiber sheet and at a right angle or an angle with respect to the traveling direction, even if the number of ejecting means is small, heat can be generated. The entire plastic fiber sheet can be processed.

  Furthermore, after spraying an air stream containing heated solid particles on the thermoplastic fiber or thermoplastic fiber sheet, excess solid particles that were not fused to the thermoplastic fiber or thermoplastic fiber sheet were recovered, and the recovered solid It is preferred to reuse the particles. As such a recovery method, for example, as illustrated in FIG. 2, a particle recovery box 91 which is a particle recovery unit on the side opposite to the side of blowing the air flow containing heated solid particles of the fiber support unit or the fiber sheet support unit. And a method of recovering excess solid particles by the particle recovery box 91 can be mentioned. Further, in order to remove excess solid particles that have not been fused to the thermoplastic fiber or thermoplastic fiber sheet, for example, a method of inclining the conveyor net 71 and dropping it by vibration or a method of collecting particles by blowing off with an air flow It is also possible to use a method using means in combination. As the particle collecting means for blowing away with the air flow, there are air blowing means comprising a blower 92 and an air nozzle 93 for blowing off the excess solid particles not fused to the thermoplastic fiber or thermoplastic fiber sheet, and a fiber supporting means or fiber. It is preferable to comprise suction boxes 94 and 95 for collecting solid particles provided on the airflow blowing side of the sheet supporting means and the opposite side.

  In this way, in the first step, the solid particle A can be brought into contact with the surface of the thermoplastic fiber, and the solid particle A can be fused with the thermoplastic resin to form a solid particle fused fiber precursor. . Alternatively, the solid particle A can be brought into contact with the thermoplastic fiber sheet, and the solid particle A can be fused with the thermoplastic resin to form a solid particle fused fiber sheet precursor. In addition, before moving to a 2nd process, it is preferable to remove the excess solid particle which was not melt | fused to a thermoplastic fiber or a thermoplastic fiber sheet.

  In addition, the solid particle fused fiber precursor or the solid particle fused fiber sheet precursor formed in the first step before moving to the second step is used in an atmosphere having a temperature equal to or higher than the melting point of the thermoplastic resin by using a dryer or the like. Under a low pressure such that the solid particles A are not buried in the surface of the thermoplastic fiber by a method such as exposing to the inside or passing between a pair of rolls or belt heated to a temperature equal to or higher than the melting point of the thermoplastic resin. It is possible to reliably fuse the solid particles A to the surface of the thermoplastic fiber by performing the heat treatment. In addition, the solid particle fusion fiber precursor or solid particle fusion fiber sheet precursor formed in the first step can be once cooled before moving to the second step. Solid particles A can be fused to the surface of the thermoplastic fiber. In the first step, the solid particles A can be fused to the front and back surfaces of the thermoplastic fiber sheet as necessary.

  In the second step of the method for producing a solid particle fused fiber according to the present invention, the solid particle B heated to a temperature higher than the melting point of the thermoplastic resin is brought into contact with the surface of the solid particle fused fiber precursor, The solid particles B are fused with a thermoplastic resin to form solid particle fused fibers. In the second step of the method for producing a solid particle fused fiber sheet according to the present invention, the solid particle B heated to a temperature higher than the melting point of the thermoplastic resin is brought into contact with the solid particle fused fiber sheet precursor, The solid particles B are fused with the thermoplastic resin to form a solid particle fused fiber sheet. Since the solid particle fusion fiber precursor has already been fused to the surface of the thermoplastic fiber in the first step, the solid particle A on the surface of the thermoplastic fiber is fused in the second step. The solid particles B are fused to the portions that are not. As shown in the examples, when water-repellent polytetrafluoroethylene particles are selected as the solid particles A, and conductive carbon black having a particle diameter smaller than that of the polytetrafluoroethylene particles is selected as the solid particles B In some cases, a part of the solid particles B may adhere to the surface of the solid particles A due to inertial collision. When the solid particles A and the solid particles B are charged, some of the solid particles B may adhere to the surface of the solid particles A due to electrostatic deposition in addition to inertial collision.

The method of bringing the heated solid particles B heated to a temperature higher than the melting point of the thermoplastic resin into contact with the surface of the solid particle fused fiber precursor or the solid particle fused fiber sheet precursor is brought into contact with the surface of the thermoplastic fiber by the contact. It is not particularly limited as long as the solid particles B can be fused, for example,
(1B) A method of spraying an air flow containing heated solid particles B onto the surface of a solid particle fused fiber precursor or a solid particle fused fiber sheet precursor;
(2B) A method in which the heated solid particles B are naturally dropped with respect to the solid particle fused fiber precursor or the solid particle fused fiber sheet precursor;
(3B) A method of shaking the heat-resistant container charged with the heated solid particles B and the solid particle fused fiber precursor or the solid particle fused fiber sheet precursor;
(4B) A method of immersing the solid particle fusion fiber precursor or the solid particle fusion fiber sheet precursor in the heated solid particles B; or
(5B) A method of exposing the solid particle fused fiber precursor or the solid particle fused fiber sheet precursor to the fluidized bed of the heated solid particles B can be exemplified.

  As a method of bringing the heated solid particles B into contact with the solid particle fused fiber precursor or the solid particle fused fiber sheet precursor, the contact method (1B), that is, the air flow containing the heated solid particles B is used as the solid particle fused fiber. When using the method of spraying the precursor or solid particle fused fiber sheet precursor surface, solid particles heated above the melting point of the thermoplastic resin having the lowest melting point among the thermoplastic resins constituting the thermoplastic fiber surface A mixed air stream in which B and the air stream are mixed is used.

  In order to prepare such a mixed airflow, the mixed airflow preparation method described in the description of the first step can be applied as it is. In addition, “(1B) the method of spraying an air flow containing heated solid particles B onto the surface of the solid particle fused fiber precursor or the solid particle fused fiber sheet precursor” described in the above-mentioned first step “(1A) In “Method of spraying air flow containing heated solid particles A onto thermoplastic fiber surface or thermoplastic fiber sheet”, the heated solid particles A are replaced with heated solid particles B, and the thermoplastic fiber surface or thermoplastic fiber sheet is fused to the solid particles. The description in the first step can be applied as it is, replacing with the fiber precursor or the solid particle fusion fiber sheet precursor surface.

  Moreover, in order to implement a 2nd process after a 1st process, for example using the apparatus shown in FIG. 1 or FIG. 2, a thermoplastic fiber or a thermoplastic fiber sheet is unwound from the raw material roll 81, and a 1st process is carried out. The solid particle fusion fiber precursor or the solid particle fusion fiber sheet precursor is formed, and the solid particle fusion fiber precursor or the solid particle fusion fiber sheet precursor is once wound up to form a work roll 82. Then, the solid particle fusion fiber precursor or the solid particle fusion fiber sheet precursor is unwound from the work roll 82, and the heated solid particles are sprayed on the same processing surface as the first step, and the second step is performed. Then, a solid particle fusion fiber or a solid particle fusion fiber sheet can be formed, and the solid particle fusion fiber or the solid particle fusion fiber sheet can be rolled up to form a product roll 83.

  Further, for example, in the apparatus shown in FIG. 1 or FIG. 2, two jetting means 40 for jetting the solid particle-containing airflow are installed so as to be front and rear with respect to the traveling direction of the thermoplastic fiber or the thermoplastic fiber sheet, and forward It is also possible to carry out the first step by means of the jetting means 40 installed on the rear side, and then to carry out the second step continuously by means of the jetting means 40 ′ (not shown) placed behind.

  In this way, in the second step, the solid particles B are brought into contact with the surface of the solid particle fused fiber precursor, and the solid particles B are fused with the thermoplastic resin to form solid particle fused fibers. be able to. Moreover, the solid particle B can be brought into contact with the solid particle fused fiber sheet precursor, and the solid particle B can be fused with the thermoplastic resin to form a solid particle fused fiber sheet.

  In the production method of the present invention, the solid particle fusion fiber or the solid particle fusion fiber having various characteristics depends on the selection method of the solid particles A and the solid particles B and the conditions for bringing the solid particles into contact with the surface of the thermoplastic fiber. A sheet can be formed.

For example, the same particles are employed for the solid particles A in the first step and the solid particles B in the second step, and in the first step, excess solid particles A that have not been fused to the thermoplastic fiber or the thermoplastic fiber sheet. After removing the second step, the solid particles A are fused to the portion where the solid particles A on the surface of the thermoplastic fiber are not fused, and the amount of the solid particles A is increased. It is possible to make it. In particular, when the shape of the particles is irregular, such as pulverized silica particles or alumina particles, the fusion may be insufficient in the first step, which is a preferable method for fusing such solid particles. For example, in the case of silica particles of Example 1 described later, the amount of fusion in the first step is 8.8 g / m ² which is close to the limit, whereas the amount of fusion after the second step is 13.0. There is an increase of about 48%. In the case of the alumina particles of Example 2, the fusion amount in the first step is 38.6 g / m ² which is close to the limit, whereas the fusion amount after the second step is 50.3. The increase is about 30%. Thus, when the fusion | melting method of a 1st process and a 2nd process is implemented on the same conditions, the increase of 20 to 70% is possible.

  Further, for example, when the solid particle A having a particle size (for example, particle size D50) larger than that of the solid particle B is first fused, a particle mixture obtained by mixing the solid particles A and the solid particles B is fused. In comparison, there is an effect that the amount of fusion of the solid particles A can be increased. This effect is obtained when the particle mixture obtained by mixing the solid particles A and the solid particles B is fused to the surface of the thermoplastic fiber in the same manner as in the first step, and the solid having a small contact area with the surface of the thermoplastic fiber. This is probably because the particles B are preferentially fused to the surface of the thermoplastic fiber. As described above, in the present invention, it is possible to obtain a solid particle fusion fiber or a solid particle fusion fiber sheet having a specific fusion amount by adopting the solid particles whose fusion amount is to be increased as the solid particles A. is there.

  In order to reduce the fusion amount of the solid particles A, the solid particles A and the solid particles B can be exchanged. In the first step, for example, the fusion amount of the solid particles A is reduced. It is possible to employ a method such as reducing the content of the heated solid particles A in the air stream containing the heated solid particles A. Thus, in the present invention, the fusion ratio of the solid particles A and the solid particles B can be freely set.

  In addition, for example, the material of the solid particles B may be selected to be different from the material of the solid particles A so that the solid particle fused fiber or the solid particle fused fiber sheet can simultaneously perform two types of functions. It is. Since the two types of solid particles exist independently, even if the two types of solid particles have contradictory functions, both functions can be exhibited simultaneously. For example, in Example 3 to be described later, a water-repellent particle made of PTFE is used as the solid particle A, and a conductive particle made of carbon black is used as the solid particle B, so that the solid particle-fused fiber sheet has a conductive and water-repellent function. Is manufacturing. Here, it can be said that the solid particles A made of PTFE are electrically insulating, and the solid particles B made of carbon black are electrically conductive and have contradictory characteristics.

Various characteristics such as surface density and thickness of the solid particle fusion fiber sheet obtained by the production method of the present invention are not particularly limited, but the surface density is preferably 3 to 650 g / m ^2. more preferably ~550g / ^{m 2,} and still more preferably from 6~450g / ^{m 2.} The thickness is preferably 0.01 to 35 mm, more preferably 0.02 to 30 mm, and still more preferably 0.03 to 25 mm.

Further, it is preferable that fusion Chakuryou of solid particles is 0.1 to 200 g / ^{m 2,} more preferably from 0.2~180g / ^{m 2,} to be 0.3~150g / ^{m 2} Further preferred.

  According to the manufacturing method of the present invention, since the heated solid particles are brought into contact with the surface of the thermoplastic fiber, only the portion where the solid particles are in contact with the surface of the thermoplastic fiber is melted to fuse the solid particles. For this reason, the surface of the solid particles other than the contact portion or the surface portion other than the fused portion is very rarely covered with the molten resin. In addition, solid particles are rarely buried by melting and fluidizing the entire resin on the surface of the thermoplastic fiber. In addition, the molten resin oozes out from the gaps between the contacted solid particles, the solid particles outside the solid particles are also fused, and the solid particles partially become a multilayer on the surface of the thermoplastic fiber, There is no problem that the solid particles are not uniformly fused on the surface of the thermoplastic fiber.

  Further, according to the production method of the present invention, since the solid particles melt only the surface of the thermoplastic fiber, even if the thermoplastic fiber is a fiber composed of a single resin component, it is heated during the contact treatment or the fusion treatment. There is no problem that the plastic fiber shrinks or the whole thermoplastic fiber is melted to cause yarn breakage. In addition, there is an advantageous effect that thermal degradation of the entire thermoplastic fiber and thermal degradation of the surface of the thermoplastic fiber do not occur, or if it occurs, it is possible to reduce it.

  In the production method of the present invention, the contact method (1A) or (1B), that is, the heated solid particles and the thermoplastic fibers or the thermoplastic fibers contained in the thermoplastic fiber sheet, are heated. When using a method in which an air stream containing solid particles is blown onto a thermoplastic fiber, the solid particles collide with the surface of the thermoplastic fiber due to the inertial force of the solid particles, and the solid particle is firmly bonded to the surface of the thermoplastic fiber. be able to.

  Further, in the solid particle fusion fiber or solid particle fusion fiber sheet in which the solid particles are fused to the surface of the thermoplastic fiber by the production method of the present invention, the solid particle fusion fiber and the solid particle fusion fiber having further enhanced functionality. It is possible to provide a fiberglass sheet.

  Examples of the present invention will be described below, but these are only suitable examples for facilitating the understanding of the present invention, and the present invention is not limited to the contents of these examples.

Example 1
(Preparation of thermoplastic fiber sheet)
By papermaking apparatus, papermaking comprising 100% of core-sheath type composite fiber (fiber diameter = 10.5 μm, fiber length = 5 mm) whose core component is polypropylene resin and whose sheath component is high-density polyethylene resin (melting point = 132 ° C.) A sheet (thermoplastic fiber sheet) was prepared. Next, this paper sheet is placed on a metal mesh conveyor belt, and the high density polyethylene resin, which is an adhesive component of the composite fiber, is melted at 140 ° C. in an air-through dryer. A heat bonding treatment was performed to obtain a raw material roll of a wet method nonwoven fabric. This wet method nonwoven fabric had a thickness of 0.27 mm and an areal density of 50 g / m ² .

(First step)
In the production apparatus shown in FIG. 2, commercially available silica particles (manufactured by Admatechs, product name: Admafine, product number SO-C3, secondary particle diameter D50: 1.5 μm) are charged into the supply container 21, and the silica particles are heated by the heater 51. Was heated to 220 ° C., and the heated silica particles were supplied to the ejector by the rotary supply control rotor 23. On the other hand, the airflow A heated to 167 ° C. generated in the blower 11 and the heating tube 12 is sent to the ejector, and the solid particles 29 supplied from the supply control rotor 23 are sucked by the suction force generated by the airflow A, and the airflow A Silica particles were mixed therein to form a silica mixed gas stream, and the silica mixed gas stream was ejected from the nozzle 41. The silica mixed gas stream contained 80 g / m ³ of silica particles.

Next, the wet process nonwoven fabric is unwound from the raw material roll 81 onto the conveyor net 71 at a speed of 5 m / min, passed under the nozzle 41, and a silica mixed gas stream is blown onto the wet process nonwoven fabric, and the core is formed by heated silica particles. A high density polyethylene resin, which is a sheath component of the sheath type composite fiber, was melted, and silica particles were fused to the surface of the core-sheath type composite fiber to form a solid particle fused fiber sheet precursor. Excess silica particles that were not fused to the wet method nonwoven fabric during the blowing of the silica mixed gas flow were collected by suction by a particle collection box 91 disposed under the conveyor net 71. Furthermore, surplus silica particles that were not fused to the wet method nonwoven fabric were blown off using the blower 92 and the air nozzle 93, and surplus silica particles were collected by suction boxes 94 and 95 provided above and below the conveyor net 71. Thereafter, the solid particle fused fiber sheet precursor was wound up as an in-process roll 82.
The areal density of the resulting solid particles fused fiber sheet precursor is 58.8 g / ^{m 2,} fused silica particles was 8.8 g / ^{m 2.}

(Second step)
Next, using the same manufacturing apparatus as in the first step, the solid particle fusion fiber sheet precursor is unwound from the in-process roll 82 on the conveyor net 71 at a speed of 5 m / min, and passed under the nozzle 41 to obtain a solid. In the first step on the surface of the core-sheath type composite fiber, a silica mixed gas stream is blown onto the particle-fused fiber sheet precursor, and the high-density polyethylene resin as the sheath component of the core-sheath type composite fiber is melted by the heated silica particles. A solid particle fused fiber sheet was formed by fusing to a portion where the particles were not fused. Excess silica particles that were not fused to the solid particle fused fiber sheet precursor during the blowing of the silica mixed gas flow were collected by suction with a particle collection box 91 disposed under the conveyor net 71. Further, excess silica particles that have not been fused to the solid particle fused fiber sheet precursor are blown off using the blower 92 and the air nozzle 93, and the surplus silica particles are removed by suction boxes 94, 95 provided above and below the conveyor net 71. It was collected. Thereafter, the solid particle fused fiber sheet was wound up as a semi-finished product roll 83.
The thickness of the obtained solid particle fusion fiber sheet is 0.283 mm, the surface density is 63.0 g / m ² , and the silica particles fused in the first step and the second step are 13.0 g / m. ² . Thus, the increase rate of the fused amount of the silica particles was 47.7% with respect to the fused amount of the silica particles in the first step of 8.8 g / m ² .

(Example 2)
Example 1 except that commercially available alumina particles (manufactured by Nippon Light Metal Co., Ltd., product name: fine alumina, product number: A34, particle size D50: 3.8 μm) were used instead of silica particles in Example 1. In the same manner, a solid particle fused fiber sheet precursor and a solid particle fused fiber sheet were obtained. The surface density of the solid particle fused fiber sheet precursor was 88.6 g / m ² , and the fused alumina particles were 38.6 g / m ² . The thickness of the solid particle fusion fiber sheet is 0.306 mm, the surface density is 100.3 g / m ² , and the alumina particles fused in the first step and the second step are 50.3 g / m ^2. Met. Thus, the increase rate of the fusion amount of alumina particles was 30.3% with respect to the fusion amount of alumina particles of 38.6 g / m ² in the first step.

(Example 3)
(Preparation of thermoplastic fiber sheet)
The same wet method nonwoven fabric and raw material roll as in Example 1 were obtained using the same papermaking apparatus as in Example 1 except that the thickness was 0.06 mm and the surface density was 10 g / m ² .

(First step)
In the production apparatus shown in FIG. 2, commercially available polytetrafluoroethylene particles (PTFE powder manufactured by Finetech Co., Ltd., particle diameter D50: 5.6 μm) (hereinafter sometimes referred to as PTFE particles) are supplied to the supply container 21. The PTFE particles were heated to 200 ° C. by the heater 51, and the heated PTFE particles were supplied to the ejector by the rotary supply control rotor 23. On the other hand, the airflow A heated to 150 ° C. generated in the blower 11 and the heating tube 12 is sent to the ejector, and the PTFE particles 29 supplied from the supply control rotor 23 are sucked by the suction force generated by the airflow A, and the airflow A PTFE particles were mixed therein to form a PTFE mixed airflow, and the PTFE mixed airflow was ejected from the nozzle 41. The PTFE mixed air stream contained 13 g / m ³ of PTFE particles.

Next, the wet process nonwoven fabric is unwound from the raw material roll 81 onto the conveyor net 71 at a speed of 12 m / min, passed under the nozzle 41, and a PTFE mixed airflow is sprayed on the wet process nonwoven fabric, and the core sheath is heated by PTFE particles. A high density polyethylene resin, which is a sheath component of the type composite fiber, was melted, and PTFE particles were fused to the surface of the core-sheath type composite fiber to form a solid particle fused fiber sheet precursor. Excess PTFE particles that were not fused to the wet process nonwoven fabric during the blowing of the PTFE mixed airflow were collected by suction by a particle collection box 91 disposed under the conveyor net. Further, excess PTFE particles that were not fused to the wet process nonwoven fabric were blown off using the blower 92 and the air nozzle 93, and the excess PTFE particles were recovered by the suction boxes 94 and 95 provided above and below the conveyor net 71. Thereafter, the solid particle fused fiber sheet precursor was wound up as an in-process roll 82.
Subsequently, the same fusion treatment was performed on the back surface of the wet method nonwoven fabric, and the wet roll nonwoven fabric 82 was wound up again. The surface density of the obtained solid particle fused fiber sheet precursor was 12.1 g / m ² , and the fused PTFE particles were 2.1 g / m ² .

(Second step)
In the production apparatus shown in FIG. 2, commercially available carbon black (manufactured by Denki Kagaku Kogyo Co., Ltd., product name: Denka Black, primary particle size: 30 to 40 nm, secondary particle size D50: 2 to 7 μm, shape: granular, material: acetylene Black) (hereinafter sometimes referred to as CB particles) is charged into the supply container 21, the CB particles are heated to 220 ° C. by the heater 51, and the heated CB particles are ejected by the rotary supply control rotor 23. Supplied to. On the other hand, the airflow A heated to 150 ° C. generated in the blower 11 and the heating pipe 12 is sent to the ejector, and the CB particles 29 supplied from the supply control rotor 23 are sucked by the suction force generated by the airflow A, The CB particles were mixed with each other to form a CB mixed airflow, and the CB mixed airflow was ejected from the nozzle 41. The CB mixed air stream contained 44 g / m ³ of CB particles, and the ejection amount was 0.5 m ³ / min.

Next, the solid particle fused fiber sheet precursor is unwound at a speed of 4 m / min from the in-process roll 82 at a speed of 4 m / min, passed under the nozzle 41, and a CB mixed airflow is fed to the solid particle fused fiber sheet precursor. The high density polyethylene resin that is the sheath component of the core-sheath composite fiber is melted by the heated CB particles, and the PTFE particles are fused in the first step on the surface of the core-sheath composite fiber. To form a solid particle fused fiber sheet. A part of the CB particles was fixed to the surface of the PTFE particles by inertial collision. In addition, surplus CB particles that were not fused to the solid particle fused fiber sheet precursor during the spraying of the CB mixed airflow were collected by suction by a particle collection box 91 disposed under the conveyor net 71. Further, excess CB particles that have not been fused to the solid particle fused fiber sheet precursor are blown off using the blower 92 and the air nozzle 93, and the excess CB particles are removed by suction boxes 94, 95 provided above and below the conveyor net 71. It was collected. Thereafter, the solid particle fused fiber sheet was wound up as a semi-finished product roll 83.
Next, the same fusion treatment was performed on the back surface of the solid particle fusion fiber sheet precursor, and the product roll 83 having a width of about 20 cm was wound up. The thickness of the obtained solid particle fusion fiber sheet is 0.066 mm, the surface density is 12.5 g / m ² , and the CB particles fused and fixed in the second step are 0.4 g / m ² . there were. Thus, PTFE particles 2.1 g / ^{m 2} and CB particles was obtained 0.4 g / ^{m 2} fusion and sticking solid particles fused fiber sheet. Further, the contact angle of the solid particle fusion fiber sheet was 143 ° on the front and back average, and this particle fusion fiber sheet was excellent in conductivity and water repellency.

Example 4
In the first step of Example 3, when the PTFE mixed air flow was ejected from the nozzle 41, the PTFE mixed air flow contained 26 g / m ³ of PTFE particles, and the solid particle fusion fiber sheet precursor from the in-process roll 82 A solid particle fused fiber sheet precursor and a solid particle fused fiber sheet were obtained in the same manner as in Example 3 except that the body was wound on the conveyor net 71 at a speed of 5 m / min. The areal density of the solid particle fused fiber sheet precursor was 14.2 g / m ² , and the fused PTFE particles were 4.2 g / m ² . The thickness of the solid particle fusion fiber sheet was 0.067 mm, the surface density was 14.5 g / m ² , and the CB particles fused and fixed in the second step were 0.3 g / m ^2. It was. Thus, a solid particle fused fiber sheet in which PTFE particles were 4.2 g / m ² and CB particles were fused and fixed to 0.3 g / m ² was obtained. Moreover, compared with the solid particle fusion | melting fiber sheet of Example 3, the adhesion amount of PTFE particle increased 2.1 g / m < ² >. Further, the contact angle of this solid particle fused fiber sheet was 144 ° in terms of front and back, and this solid particle fused fiber sheet was excellent in conductivity and water repellency.

(Example 5)
In the second step of Example 3, after forming the solid particle fused fiber sheet, the solid particle fused fiber sheet precursor fused with the CB particles is passed between belts heated to 130 ° C. After this step, excess CB particles that have not been fused to the solid particle fused fiber sheet precursor are blown off using the blower 92 and the air nozzle 93, and the conveyor net 71 is blown. A solid particle fused fiber sheet precursor and a solid particle fused fiber sheet were obtained in the same manner as in Example 3 except that the excess CB particles were collected by suction boxes 94 and 95 provided above and below. The surface density of the solid particle fused fiber sheet precursor was 12.1 g / m ² , and the fused PTFE particles were 2.1 g / m ² . The thickness of the solid particle fused fiber sheet was 0.065 mm, the surface density was 13.9 g / m ² , and the CB particles fused and fixed in the second step were 1.8 g / m ^2. It was. Thus, PTFE particles 2.1 g / ^{m 2} and CB particles was obtained 1.8 g / ^{m 2} fusion and sticking solid particles fused fiber sheet. Moreover, compared with the solid particle fusion fiber sheet of Example 3, the amount of fusion and fixation of CB particles increased by 1.4 g / m ² . Further, the contact angle of the solid particle fused fiber sheet was 145 ° on the front and back average, and this solid particle fused fiber sheet was excellent in conductivity and water repellency.

(Example 6)
In the first step of Example 3, when the PTFE mixed gas stream was ejected from the nozzle 41, the PTFE mixed gas stream contained 26 g / m ³ of PTFE particles, and the solid particle fusion fiber sheet precursor from the in-process roll 82. The solid particle fused fiber in which the CB particles were fused after forming the solid particle fused fiber sheet in the second step of Example 3 in which the body was wound on the conveyor net 71 at a speed of 5 m / min. A step of reliably fusing the CB particles by passing the sheet precursor through a belt heated to 130 ° C. is added, and after this step, solid blown fibers using the blower 92 and the air nozzle 93 are used. The excess CB particles that were not fused to the sheet precursor are blown off, and the excess CB particles are provided by suction boxes 94 and 95 provided above and below the conveyor net 71. A solid particle fused fiber sheet precursor and a solid particle fused fiber sheet were obtained in the same manner as in Example 3 except that was recovered. The areal density of the solid particle fused fiber sheet precursor was 14.2 g / m ² , and the fused PTFE particles were 4.2 g / m ² . The thickness of the solid particle fused fiber sheet was 0.067 mm, the surface density was 15.8 g / m ² , and the CB particles fused and fixed in the second step were 1.6 g / m ^2. It was. Thus, a solid particle fused fiber sheet in which PTFE particles were 4.2 g / m ² and CB particles were fused and fixed to 1.6 g / m ² was obtained. Moreover, compared with the particle fusion | melting fiber sheet of Example 3, the adhesion amount of PTFE particle increased 2.1 g / m < ² >, and the fusion | bonding amount and adhesion amount of CB particle | grain increased 1.2 g / m < ² >. Further, the contact angle of the solid particle fused fiber sheet was 145 ° on the front and back average, and this solid particle fused fiber sheet was excellent in conductivity and water repellency.

(Example 7)
In the “preparation of thermoplastic fiber sheet” in Example 3, a wet process nonwoven fabric and a raw material roll having a thickness of 0.150 mm and an area density of 30 g / m ² were obtained using the same papermaking apparatus as in Example 1. A solid particle fused fiber sheet precursor and a solid particle fused fiber sheet were obtained in the same manner as in Example 3 except that it was obtained. Surface density of the solid particles fused fiber sheet precursor is 38.7 g / ^{m 2,} the fused PTFE particles was 8.7 g / ^{m 2.} The thickness of the solid particles fused fiber sheet was 0.170 mm, the surface density is 40.1 g / ^{m 2,} CB particles fusion and fixed by the second step is 1.4 g / ^{m 2} met It was. Thus, PTFE particles 8.7 g / ^{m 2} and CB particles was obtained 1.4 g / ^{m 2} fusion and sticking solid particles fused fiber sheet. Moreover, compared with the solid particle fusion | melting fiber sheet of Example 3, the adhesion amount of PTFE particle | grains increased 6.6 g / m < ² >, and the fusion | bonding amount and adhesion amount of CB particle | grains increased 1.0 g / m < ² >. Further, the contact angle of this solid particle fused fiber sheet was 144 ° in terms of front and back, and this solid particle fused fiber sheet was excellent in conductivity and water repellency.

(Example 8)
In the “preparation of thermoplastic fiber sheet” in Example 3, a wet process nonwoven fabric and a raw material roll having a thickness of 0.150 mm and an area density of 30 g / m ² were obtained using the same papermaking apparatus as in Example 1. In the second step of Example 3 obtained, and after forming the solid particle fused fiber sheet, the solid particle fused fiber sheet precursor having the CB particles fused is passed between the belts heated to 130 ° C. By adding a step of reliably fusing the CB particles, after this step, the excess CB particles that have not been fused to the solid particle fused fiber sheet precursor using the blower 92 and the air nozzle 93 are added. The solid particle fusion fiber sheet precursor and the solid particle fused fiber sheet precursor were collected in the same manner as in Example 3 except that the excess CB particles were recovered by suction boxes 94 and 95 provided above and below the conveyor net 71. And a solid particle fused fiber sheet. Surface density of the solid particles fused fiber sheet precursor is 38.7 g / ^{m 2,} the fused PTFE particles was 8.7 g / ^{m 2.} The thickness of the solid particle fusion fiber sheet was 0.168 mm, the surface density was 42.4 g / m ² , and the CB particles fused and fixed in the second step were 3.7 g / m ^2. It was. Thus, PTFE particles 8.7 g / ^{m 2} and CB particles was obtained 3.7 g / ^{m 2} fusion and sticking solid particles fused fiber sheet. Moreover, compared with the solid particle fusion | melting fiber sheet | seat of Example 3, the adhesion amount of PTFE particle increased 6.6 g / m < ² >, and the fusion amount and adhesion amount of CB particle | grain increased 3.3 g / m < ² >. Further, the contact angle of this solid particle fused fiber sheet was 143 ° on the front and back average, and this solid particle fused fiber sheet was excellent in conductivity and water repellency.

(Comparative Example 1)
In Example 3, the same procedure as in Example 3 was performed except that the first step was not performed and that the thermoplastic fiber sheet was used in the second step without using the solid particle fused fiber sheet precursor. A solid particle fused fiber sheet was obtained.
The thickness of the resulting solid particles fused fiber sheet was 0.060 mm, the surface density is 10.8 g / ^{m 2,} the solid particles fused fiber sheet CB particles were 0.8 g / ^{m 2} fusion Obtained. Moreover, the contact angle of this solid particle fusion fiber sheet is 141 ° on the front and back average, and this solid particle fusion fiber sheet is excellent in conductivity but inferior in water repellency as compared with Example 3. It was a thing.

(Comparative Example 2)
In Example 3, the first step was not performed, the thermoplastic fiber sheet was used in the second step without using the solid particle fused fiber sheet precursor, and the solid particle fused fiber sheet was formed. Thereafter, a process of reliably fusing the CB particles by passing between belts heated to 130 ° C. is added, and after this process, the blower 92 and the air nozzle 93 are used to fuse the CB particles to the thermoplastic fiber sheet. Excess CB particles that were not blown off and a solid particle fused fiber sheet was obtained in the same manner as in Example 3 except that the excess CB particles were collected by suction boxes 94 and 95 provided above and below the conveyor net 71. .
The thickness of the resulting solid particles fused fiber sheet was 0.060 mm, the surface density is 12.4 g / ^{m 2,} the solid particles fused fiber sheet CB particles were 2.4 g / ^{m 2} fusion Obtained. Further, the air permeability (fragile type method) of this solid particle fused fiber sheet is 287 cm ³ / cm ² · s, the contact angle is 139 ° on the front and back average, and this solid particle fused fiber sheet is electrically conductive. Although it was excellent in property, it was inferior in water repellency compared with Example 3.

DESCRIPTION OF SYMBOLS 10 Airflow generation means 11 Blower 12 Heating pipe 20 Particle supply means 21 Supply container 23 Rotary supply control rotor 29 Solid particle 30 Particle mixing means, ejector 31 Portion 40 to which heated solid particles are supplied 40 Ejection means 41 Nozzles 50, 51, 52, 53 Heating means 70 Roll or fiber support means 70 'Roll or fiber sheet support means 71 Conveyor net or fiber sheet support means 80 Fiber 80' Fiber sheet 81 Raw material roll 82 In-process roll 83 Semi-finished roll, product roll 91 Particles Collection box 92 Blower 93 Air nozzle 94, 95 Suction box

Claims (4)

This is a method for producing a solid particle fused fiber in which solid particles A and solid particles B having a melting point or decomposition temperature higher than the melting point of the thermoplastic resin are fused at least to the surface of a thermoplastic fiber made of a thermoplastic resin. And
The solid particles A heated to a temperature higher than the melting point of the thermoplastic resin are brought into contact with the surface of the thermoplastic fiber, and the solid particles A are fused by the thermoplastic resin to form a solid particle fused fiber precursor. Then, the thermoplastic resin is heated to a temperature higher than the melting point of the thermoplastic resin , and the solid particles B having a large particle diameter of the solid particles A are brought into contact with the surface of the solid particle fused fiber precursor, thereby the thermoplasticity. A method for producing a solid particle fusion fiber, wherein the solid particle B is fused with a resin. 2. The method for producing a solid-particle fused fiber according to claim 1, wherein the solid particles A are polytetrafluoroethylene particles, and the solid particles B are carbon black. Solid particles A and solid particles B having a melting point or decomposition temperature higher than the melting point of the thermoplastic resin are fused to the surface of the thermoplastic fiber of a thermoplastic fiber sheet including a thermoplastic fiber having at least a surface made of a thermoplastic resin. A method for producing a solid-particle fused fiber sheet comprising:
The solid particles A heated to a temperature higher than the melting point of the thermoplastic resin are brought into contact with the thermoplastic fiber sheet, and the solid particles A are fused by the thermoplastic resin to form a solid particle fused fiber sheet precursor. Next, the thermoplastic resin is heated to a temperature higher than the melting point of the thermoplastic resin and the solid particles B having a large particle diameter of the solid particles A are brought into contact with the solid-fiber-fused fiber sheet precursor, The method for producing a solid particle fused fiber sheet, characterized in that the solid particles B are fused. The method for producing a solid-particle-fused fiber sheet according to claim 1, wherein the solid particles A are polytetrafluoroethylene particles, and the solid particles B are carbon black.

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