JP2013204156A - Method for producing fiber sheet with fixed particles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a fiber with fixed particles that includes fixing solid particles on a fiber sheet comprising thermoplastic fibers, and the method that makes it possible to surly fix the solid particles or to increase the amount of the solid particles fixed.SOLUTION: The method for producing a fiber sheet with fixed particles includes fixing, on a fiber sheet comprising thermoplastic fiber at least a surface of which is made of a thermoplastic resin, solid particles having a melting point or decomposition temperature higher than the melting point of the thermoplastic resin. When contacting a particle containing air flow including the solid particles having a higher temperature than the melting point of the thermoplastic resin with the fiber sheet to melt and solidify the thermoplastic resin to fix the solid particles on the fiber sheet, a heating air flow having an air flow direction different from the air flow direction of the particle containing air flow is brought into contact with a part where the particle containing air flow contacts with the fiber sheet.

Description

  The present invention relates to a method for producing a particle-fixed fiber sheet.

  As a method for producing a solid particle-supporting fiber sheet in which solid particles are supported on a fiber sheet, Patent Document 1 discloses that a fiber sheet containing fibers made of a thermoplastic resin is heated to a temperature higher than the melting point of the thermoplastic resin. The solid particles are supported by fusing the thermoplastic resin on the fiber surface by blowing an air stream containing the solid particles on the fiber sheet surface, and then cooling the solid particle fused fiber sheet, A method for fixing solid particles to the fiber surface is disclosed.

  The solid particle-carrying fiber sheet obtained by this production method is compared with the solid particle-carrying fiber sheet obtained by melting the surface of the thermoplastic fiber in advance and fusing the solid particles to the molten thermoplastic fiber. In addition, 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.

JP 2004-3070 A

  The present invention solves the above problems, and in the method for producing a particle-fixed fiber sheet in which solid particles are fixed to a fiber sheet containing thermoplastic fibers, the solid particles can be reliably fixed or It is an object of the present invention to provide a method for producing a particle-fixed fiber sheet capable of increasing the amount of fixing.

  In order to solve the above-mentioned problem, in the invention according to claim 1, solid particles having a melting point or decomposition temperature higher than the melting point of the thermoplastic resin are fixed to a fiber sheet including a thermoplastic fiber having at least a surface made of a thermoplastic resin. A method for producing a particle-fixed fiber sheet, wherein the thermoplastic resin is melted and solidified by bringing a particle-containing airflow containing the solid particles having a temperature higher than the melting point of the thermoplastic resin into contact with the fiber sheet. When solid particles are fixed to the fiber sheet, a heated airflow having an airflow direction different from the airflow direction of the particle-containing airflow is brought into contact with a portion where the particle-containing airflow contacts the fiber sheet. The method for producing the particle-fixed fiber sheet was used as the solution.

  According to the present invention, in a method for producing a particle-fixed fiber sheet in which solid particles are fixed to a fiber sheet containing thermoplastic fibers, the solid particles can be reliably fixed or the amount of solid particles fixed can be increased. It was.

It is a block diagram which shows typically an example of the manufacturing apparatus of the particle | grain fixed fiber sheet used with the manufacturing method of this invention. It is the schematic which shows typically an example of the manufacturing apparatus of the particle | grain fixed fiber sheet used with the manufacturing method of this invention. It is another schematic diagram which shows typically an example of the manufacturing apparatus of the particle | grain fixed fiber sheet used with the manufacturing method of this invention. 2 is an electron micrograph of the surface of the particle-fixed fiber sheet obtained in Example 1 (a surface on which the alumina particle-containing airflow D has been sprayed). It is an electron micrograph of the back surface (surface to which the heated airflow E was sprayed) of the particle fixed fiber sheet obtained in Example 1. It is an electron micrograph of the back surface (surface to which the heating airflow E was sprayed) of the particle fixed fiber sheet obtained in Example 2. It is an electron micrograph of the back surface (surface to which the heating airflow E was sprayed) of the particle fixed fiber sheet obtained in Example 4. It is an electron micrograph of the back surface (the surface opposite to the surface on which the alumina particle-containing airflow D is sprayed) of the particle fixed fiber sheet obtained in Comparative Example 1. It is an electron micrograph of the surface (surface to which the alumina particle containing airflow D was sprayed) of the particle fixed fiber sheet obtained in Example 5. It is an electron micrograph of the back surface (surface to which the heating airflow E was sprayed) of the particle fixed fiber sheet obtained in Example 5. It is an electron micrograph of the back surface (surface to which the heating airflow E was sprayed) of the particle fixed fiber sheet obtained in Example 6. It is an electron micrograph of the back surface (surface to which the heated airflow E was sprayed) of the particle fixed fiber sheet obtained in Example 7. It is an electron micrograph of the back surface (the surface opposite to the surface on which the alumina particle-containing airflow D is sprayed) of the particle fixed fiber sheet obtained in Comparative Example 2.

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

  The method for producing a particle-fixed fiber sheet according to the present invention is a particle-fixing method in which solid particles having a melting point or decomposition temperature higher than the melting point of the thermoplastic resin are fixed to a fiber sheet including a thermoplastic fiber having at least a surface made of a thermoplastic resin. A method for producing a fiber sheet, wherein the thermoplastic resin is melted and solidified by bringing a particle-containing airflow containing the solid particles having a temperature higher than the melting point of the thermoplastic resin into contact with the fiber sheet. When adhering to the fiber sheet, a heated air stream having an airflow direction different from the airflow direction of the particle-containing airflow is brought into contact with a portion where the particle-containing airflow contacts the fiber sheet.

  The thermoplastic fiber contained in the fiber sheet used in the method for producing a particle-fixed fiber sheet of the present invention is a fiber having at least a surface made of a thermoplastic resin, and the fiber surface is heated (for example, heated at 50 ° C. or higher, preferably Any fiber can be selected as appropriate as long as it is a fiber that melts by heating at 80 ° C. or higher. 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 blowing method, flash spinning method, electrostatic spinning method, spinning raw 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 the particle-fixed 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. In addition, it is possible to include only the thermoplastic fibers, or it is possible to include 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. Further, when 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 (spun bond method, melt blow method, flash spinning method, electrostatic spinning 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. According to the production method of the present invention, when the surface density is high or the thickness is thick, the effect of the present invention tends to be remarkable. However, the thermoplastic fiber sheet is used in a melt-blowing method, a flash spinning method, or an electrostatic spinning method. In the case of a thermoplastic fiber sheet using ultrafine fibers by the method or the like, good effects can be obtained even when the surface density is low or the thickness is thin. 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 Seisakusho 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 used in the method for producing a particle-fixed fiber sheet according to the present invention are solid particles 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 fixing the solid particles. As long as it is a particle, it can be either inorganic or organic. Examples of the material of such solid particles include silicon carbide, activated carbon, zeolite, carbon particles, tourmaline, calcium carbonate, metal particles, metal oxide particles such as silica, alumina, and titanium oxide, or water-absorbing resin, ion exchange. Various materials such as a resin and a functional resin such as a water repellent 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 fixed to the surface of the thermoplastic fiber. That is, even if solid particles are not fixed to the surface of the thermoplastic fiber, or solid particles are fixed to the surface of the thermoplastic fiber, the solid particles are dissolved before the fiber surface and the solid particles are aggregated. Or the solid particles and the fiber surface are fixed in a wide area, and the effective area of the fixed 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 fixed on the fiber surface. Moreover, even if it is going to obtain the fiber which such a solid particle fixed, it may become difficult to fix a solid particle on 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 using a laser diffraction / scattering particle size distribution measuring instrument (for example, LMS-30 manufactured by Seishin Enterprise Co., Ltd.). It can be determined by measuring 500 or more solid particles as solid particles or secondary particles that have become aggregates.

  In the method for producing a particle-fixed fiber sheet according to the present invention, the thermoplastic resin is melted and solidified by bringing a particle-containing airflow containing the solid particles having a temperature higher than the melting point of the thermoplastic resin into contact with the fiber sheet, so that the solid When the particles are fixed to the fiber sheet, a heating airflow having an airflow direction different from the airflow direction of the particle-containing airflow is brought into contact with a portion where the particle-containing airflow contacts the fiber sheet. In the method, it is preferable to use the manufacturing apparatus illustrated in FIGS.

  FIG. 1 is a block diagram schematically showing an example of an apparatus used in the production method of the present invention. A thermoplastic fiber sheet 80 is used as an object to be processed, and a thermoplastic fiber sheet 80 is used as an object support means. By using the fiber sheet support means 70 which can be supported, it can be used as a production apparatus of the particle fixed fiber sheet according to the present invention.

  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 fed into the fed air stream by the particle supply means 20, thereby mixing the air stream and the solid particles to form a particle-containing air stream. Particle mixing means 30 capable of performing; jetting means 40 connected to the particle mixing means 30 and jetting the particle-containing airflow formed by the particle mixing means 30; and the particle-containing airflow is in contact with the fiber sheet A heated air flow ejecting means 60 for bringing the heated air flow into contact with the portion from a direction different from the air flow direction of the particle-containing air flow; 10, heating means 50, 51, 52, 53, 55 provided on the particle supply means 20, the particle mixing means 30, the ejection means 40, and the heated airflow ejection means 60, respectively; Fiber sheet supporting means 70 capable of holding the thermoplastic fiber sheet 80 at a position where the ejected particle-containing airflow can come into contact with the thermoplastic fiber sheet is included.

  In the manufacturing method according to the present invention, it is more preferable to use the apparatus shown in FIG. 2 and 3 are schematic views schematically showing an example of an apparatus used in the production method of the present invention. Like the embodiment shown in FIG. 1, a thermoplastic fiber sheet 80 is used as an object to be processed, and By using the fiber sheet support means 70 or 71 capable of supporting the thermoplastic fiber sheet 80 as the treated product support means, it can be used as an apparatus for producing a solid particle fused fiber sheet according to the present invention.

As described above, in order to bring the particle-containing airflow containing the heated solid particles into contact with the thermoplastic fiber sheet, the melting point of the thermoplastic resin having the lowest melting point is higher than the melting point of the thermoplastic resin constituting the thermoplastic fiber surface. A particle-containing air stream in which heated solid particles and an air stream are mixed is used. To prepare such particle-containing 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 particle-containing airflow preparation method (b) or (c), the solid particles are heated above the melting point of the thermoplastic resin via 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 particle-containing airflow preparation method (a), a method of supplying solid particles heated to a temperature higher than the melting point of the thermoplastic resin to an airflow heated to a temperature of 50 ° C. or 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. In addition, if a particle-containing airflow in which solid particles are mixed in an airflow is sprayed on the fiber sheet, an excessively high temperature airflow hits the fibers constituting the fiber sheet, causing fiber breakage or shrinkage. When it occurs, it is preferably an air stream heated to a temperature of 50 ° C. or lower than the melting point of the thermoplastic resin and further heated to a temperature lower than the temperature of the heated solid particles.

  In any of the above methods for preparing each particle-containing airflow (a), (b), or (c), the particle-containing airflow after the airflow and the solid particles are mixed is heated as necessary. It is preferable to heat above the melting point of the plastic resin. 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 generation 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, Using a method of heating to a temperature equal to or higher than the melting point of the thermoplastic resin, or a device such as a fluidized bed type dryer generally used as a powder dryer, the temperature of the thermoplastic resin (for example, A method of heating the solid particles to a temperature equal to or higher than the melting point 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 generation 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 bring the airflow containing the heated solid particles into contact with the thermoplastic fiber sheet, the particle-containing airflow D obtained as described above (that is, among the thermoplastic resins constituting the surface of the thermoplastic fiber). It is preferable to spray the thermoplastic fiber sheet with a particle-containing air flow D) containing solid particles heated above the melting point of the thermoplastic resin having the lowest melting point. Prior to spraying, the temperature of the surface of the thermoplastic fiber or the thermoplastic fiber sheet can be set to a temperature lower than the melting point of the thermoplastic resin and a temperature difference with the melting point within 20 ° C.

  As a method of spraying the thermoplastic fiber sheet, for example, as illustrated in FIG. 2, when the particle-containing airflow D containing solid particles is ejected from the nozzle 41 as the ejection means, the solid particles are given at the time of ejection. It collides with the surface of the thermoplastic fiber due to inertial force due to 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 FIGS. 1 to 3, it is preferable to bring the particle-containing airflow into contact with the thermoplastic fiber sheet supported by the movable fiber sheet support means. Preferable examples of such support means include, for example, a rotating roll 70 on which a thermoplastic fiber sheet is placed, and both sides of the thermoplastic fiber sheet are gripped with pins or grips before and after the treatment region where the particle-containing airflow is contacted. A tenter-type device that moves while moving, a pair roll that supports a thermoplastic fiber sheet, or an opening support that can be sprayed while placing a thermoplastic fiber sheet (for example, conveyor net 71) Can do.

  Moreover, in order to spray uniformly in the width direction of a thermoplastic fiber sheet, it is possible to install a plurality of jetting means for the particle-containing air flow, or to provide a plurality of nozzle holes provided in the jetting means. 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.

  Furthermore, after bringing the particle-containing airflow into contact with the thermoplastic fiber sheet, it is preferable to recover excess solid particles that have not been fused to the thermoplastic fiber sheet and to reuse the recovered solid particles. As such a recovery method, for example, as illustrated in FIG. 2, a particle recovery box 91 as a particle recovery unit is arranged on the side opposite to the side on which the particle-containing air current is blown of the fiber sheet support unit, and this particle recovery is performed. A method of recovering excess solid particles by placing the box 91 in a reduced pressure state and providing a function as a suction box can be mentioned. Also, in order to remove excess solid particles that did not adhere to the thermoplastic fiber sheet, for example, a method of using a particle recovery means of a method of tilting the conveyor net 71 and dropping it by vibration or a method of blowing off with an air flow It can also be used in combination. As the particle collecting means for blowing away with the air flow, the air blowing means comprising a blower 92 and an air nozzle 93 for blowing off excess solid particles not fixed to the thermoplastic fiber sheet, the air flow blowing side of the fiber sheet supporting means, It is preferable that it is comprised from the suction boxes 94 and 95 which collect | recover the solid particles provided in the other side.

  In the production method of the present invention, as described above, the thermoplastic resin is melted and solidified by bringing the particle-containing airflow containing the solid particles having a temperature higher than the melting point of the thermoplastic resin into contact with the fiber sheet. Solid particles are fixed to the fiber sheet, and at that time, a heated airflow having an airflow direction different from the airflow direction of the particle-containing airflow is brought into contact with a portion where the particle-containing airflow contacts the fiber sheet. It is characterized by that.

  The heating airflow means an airflow that has become higher than the surrounding ambient temperature due to heating. In addition, although it is preferable that the said heating airflow does not contain a solid particle, it is also possible to contain a solid particle. For example, in this production method, from the airflow after the particle-containing airflow is brought into contact with the fiber sheet, the airflow containing residual solid particles from which solid particles have not been completely removed is reused to form a heated airflow. In this case, a heated air stream containing a small amount of solid particles is used.

  Moreover, the part where particle-containing airflow contacts with the said fiber sheet means the three-dimensional area | region which includes all the points where particle-containing airflow contacts with each fiber which comprises the said fiber sheet. Moreover, the air flow direction of the particle-containing airflow means the direction indicated by the center line of the particle-containing airflow in the direction from the upstream side to the downstream side of the airflow. Note that the particle-containing airflow may spread more on the downstream side than on the upstream side, and the airflow may bend. Assuming such a case, the center line is “at the point where the center line passes (referred to as the center point), the center of gravity in the airflow section perpendicular to the center line before and after the center line matches the center point. It means a straight line or a curve in which center points are continuously connected along the air flow. Similarly, the portion where the heated airflow contacts the fiber sheet refers to a three-dimensional region including all points where the heated airflow contacts the individual fibers constituting the fiber sheet. The airflow direction of the heated airflow means a direction indicated by the center line of the heated airflow in the direction from the upstream side to the downstream side of the airflow. In addition, like the particle-containing airflow, the heating airflow may be further spread on the downstream side than the upstream side, and the airflow may be bent. The definition of the center line is the same as described above. Further, when determining whether or not the airflow direction of the particle-containing airflow and the airflow direction of the heating airflow are the same direction, if one or both of these airflows are curved, the center of both If the lines are not the same shape, they can be considered as different airflow directions.

Moreover, when the heating airflow which has the airflow direction different from the airflow direction of the said particle | grain containing airflow is made to contact the part where the said particle | grain containing airflow contacts the said fiber sheet, the said particle | grain containing airflow contacts the said fiber sheet. The portion _RP and the portion _RH where the heated airflow contacts the fiber sheet must be at least partially overlapped, and the entire portion _RP or _RH is not necessarily the other portion _RH. or you need not be included in the R _P.

In the present invention, as long as a heated airflow having an airflow direction different from the airflow direction of the particle-containing airflow is brought into contact with the portion where the particle-containing airflow is in contact with the fiber sheet, that is, the particle-containing airflow is the fibersheet. a portion R _P in contact with the heated gas flow is overlaps at least partially a part R _H in contact with the fiber sheet, moreover unless the airflow direction of the heated gas flow and air flow direction of the particle-containing air stream is different , airflow direction of heated gas flow is not particularly limited, for example, as shown in FIG. 2, for the portion R _P particle-containing air stream D is in contact with the fiber sheet 80, (fiber sheet direction from the lower right of the heated gas flow E 80 lower, and the fiber sheet unwinding side) can direction toward the contact portion R _P. Such a heated air flow E can be generated by ejecting heated air from the tip of the nozzle 60 illustrated in FIG.

In the present invention, by this way particle-containing stream D is to the portion R _P in contact with the fiber sheet, wherein the air flow direction of the particle-containing gas stream is contacted with heated gas flow E having different airflow direction, (1) When the particle-containing airflow comes into contact with the fiber sheet and further passes through the fiber sheet, the temperature of the particle-containing airflow decreases, and the temperature of the solid particles also decreases, and the solid particles sufficiently melt the fiber surface. The phenomenon that it becomes impossible to solidify can be prevented. In addition, (2) the temperature of the particle-containing airflow is lowered by the contact of the particle-containing airflow with the fiber sheet accompanied by the surrounding low-temperature air, and the temperature of the solid particles is lowered accordingly. However, the phenomenon that the surface of the fiber cannot be sufficiently melted and solidified can be prevented. (3) As shown in FIG. 2, when the particle recovery box 91 in a reduced pressure state is provided, the particle recovery box 91 increases the ambient low-temperature air associated with the particle-containing airflow. The temperature of the particle-containing airflow further decreases, and the temperature of the solid particles also decreases accordingly, and the phenomenon that the solid particles cannot sufficiently melt and solidify the fiber surface becomes remarkable. Can be prevented.

In Figure 2, for the portion R _P particle-containing air stream D is in contact with the fiber sheet 80, (lower fiber sheet 80, and the fiber sheet unwinding side from) the direction of the heated gas flow E from the lower right contact portion R _Although the form toward _P is shown, as illustrated in FIG.
In addition to the form of the heated airflow E ₁ from the lower right (from the lower side of the fiber sheet 80 and the unwinding side of the fiber sheet) toward the contact portion _RP , the direction of the heated airflow E is
(Lower, and fibers from the sheet take-up side of the fiber sheet 80) in the form heated gas flow E ₂ toward the contact portion R _P direction from the lower left of the heated gas flow E,
(Upper fiber sheet 80, and fibers from the sheet unwinding side) direction of the heated gas flow E from the upper right form of heated gas flow E ₃ toward the contact portion R _P,
Or direction of heated gas flow E from the upper left (upper side of the fiber sheet 80, and fibers from the sheet take-up side) form of heated gas flow E ₄ toward the contact portion R _P,
Can be adopted. It is also possible to employ a combination of two or more forms of the four forms of these heated gas flow E ₁ to E _4.

All of these four types of heating airflows E _{1 to} E ₄ have all the three effects (1) to (3) described above, but in the case of the heating airflow E ₁ and the heating airflow E ₂ . In particular, in (1), “When the particle-containing airflow comes into contact with the fiber sheet and further passes through the fiber sheet, the temperature of the particle-containing airflow decreases, and accordingly, the temperature of the solid particles also decreases. It is excellent in the effect that the phenomenon that the fiber surface cannot be sufficiently melted and solidified can be prevented. Also, when the heated gas flow E ₃ and heated gas flow E _4, by contact with the fiber sheet in particular (2) of "the particle-containing air stream to entrain cold air around the temperature of the particle-containing air stream is reduced As a result, the temperature of the solid particles also decreases, and the effect that the solid particles cannot sufficiently melt and solidify the fiber surface can be prevented. When the particle collection box 91 is provided, the particle collection box 91 increases the ambient low-temperature air accompanying the particle-containing airflow, so that the temperature of the particle-containing airflow further decreases, and the solid particles The temperature decreases and the phenomenon that solid particles cannot sufficiently melt and solidify the fiber surface becomes remarkable, but this phenomenon can also be prevented. .

Also, when the heated gas flow E ₃ and heated gas flow E _4, to prevent turbulence caused when the particle-containing air stream D is in contact with the fiber sheet 80, it can be expected effect of controlling the flow of particle-containing gas stream D. Also, when the heated gas flow E ₁ and heated gas flow E _3, with respect to the center point of the portion R _P particle-containing air stream D is in contact with the fiber sheet 80, the contact heated gas flow E ₁ or heated gas flow E ₃ is the fiber sheet 80 The center point of the portion _RH to be moved can be moved slightly to the unwinding side of the fiber sheet 80, and the effects (1) to (3) described above can be obtained more excellently.

  As described above, the heated airflow E can be generated by ejecting heated air from the tip of the nozzle 60 illustrated in FIG. The form of the nozzle 60 can be a shape suitable for the ejection of fluid, for example, the flow path is narrowed to increase the flow velocity of the heated air flow, or the ejection angle of the heated air flow In order to widen, the tip of the nozzle can be widened. Moreover, it can be set as the nozzle shape corresponding to the shape of the nozzle 41 which ejects the particle | grain containing airflow D, and when the shape of the ejection port of the nozzle 41 is slit shape, the shape of the ejection port of the nozzle 60 is also the same width. It is possible to make it into the slit shape which has. In addition, if the number of nozzles 60 is the same as the number of nozzles 41 that eject the particle-containing airflow D, heating airflow E having different conditions is generated according to the ejection state of each nozzle 41. Can do. The method for forming the heated airflow is not particularly limited. For example, an airflow generated by a blower or the like is sent to the nozzle 60 as illustrated in FIG. can do.

In FIG. 3, the heated airflows E _{1 to} E ₄ are generated using the nozzles 61 to 64, but the nozzles 63 and 64 located on the upper part of the fiber sheet 80 are integrated with the nozzle 41 that ejects the particle-containing airflow D. It is also possible to obtain a combined nozzle.

In FIG. 3, the production apparatus for the particle-fixed fiber sheet is shown as a cross-sectional view with respect to the traveling direction of the fiber sheet 80. In this cross-section, each center line of the heated airflows E _{1 to} E ₄ and the particle-containing airflow D Any of the heating airflows E _{1 to} E ₄ is 45 ° (an angle between 0 and 90 °) formed by the center line. However, the angle between the center line of the heating airflows E _{1 to} E _{4 and} the centerline of the particle-containing airflow D is such that the nozzle 41, the nozzle 60 (or 61 to 64), the conveyor net 71, the particle recovery box 91, and the like are arranged. It is not particularly limited as long as it is possible, and when the center line of the particle-containing airflow D is perpendicular to the conveyor net 71, it is preferably 15 to 75 °, and more preferably 30 to 60 °. . When the angle is less than 15 °, the nozzle 60 and the nozzle 41 may be too close to dispose the nozzle 60, or the nozzle 60 and the particle recovery box 91 may be too close to dispose the nozzle 60. In addition, when it is less than 15 degrees, it is possible to set it as the composite nozzle which integrated the nozzles 63 and 64 located in the upper part of the fiber sheet 80 with the nozzle 41 as mentioned above. When the angle is 75 °, the nozzle 60 and the conveyor net 71 are too close to each other and the nozzle 60 cannot be disposed, or the angle formed between the heated air flow E and the fiber sheet 80 is too small, so that the heated air flow E causes the fiber sheet 80 to move. It may not be possible to sufficiently heat. Further, in order to sufficiently bring the heated air flow E into contact with the fiber sheet 80, the center line of the particle-containing air flow D is not disposed perpendicularly to the conveyor net 71, for example, at the position of the nozzle 63, and the particle-containing air flow D It is also possible for the center line of the above to form an angle of 30 to 60 ° with respect to the conveyor net 71. In this case, the angle formed by the center line of the heated air stream E ₁ or E _{4 and} the center line of the particle-containing air stream D is preferably 15 to 90 °, and more preferably 30 to 90 °.

  The temperature, air volume, and wind speed of the heated airflow E are appropriately set according to various conditions such as the melting point of the fiber sheet, the heating temperature of the solid particles, the temperature of the particle-containing airflow D, the airflow of the particle-containing airflow D, and the wind speed. Is possible. As an example of setting these conditions, first, the heating temperature of the solid particles is set to a high temperature so long as it does not exceed the melting point or decomposition temperature of the solid particles, and the fiber sheet is not broken. Next, the temperature of the particle-containing air flow D is set to a temperature equal to or higher than a temperature lower by 50 ° C. than the melting point of the fiber sheet. Next, it is preferable to set the temperature of the heated airflow E to a temperature around the temperature of the particle-containing airflow D. More specifically, the temperature of the heated airflow E is preferably equal to or higher than the temperature of the particle-containing airflow D, and is 20 ° C or lower than the melting point of the thermoplastic resin of the thermoplastic fiber contained in the fiber sheet. It is more preferable that the temperature is not higher than the melting point of the thermoplastic resin by 10 ° C. Even if the temperature of the heated airflow E is slightly higher than the melting point of the thermoplastic resin, the heated airflow E momentarily comes into contact with the fiber sheet, and thus depends on the temperature conditions of the particle-containing airflow D. It does not even have the effect of burying solid particles by melting the surface of the thermoplastic fiber. On the other hand, since the heated solid particles remain in contact with the surface of the thermoplastic fiber, there is an effect of melting and solidifying the thermoplastic resin on the surface of the thermoplastic fiber by the amount of heat of the solid particles.

Although various characteristics such as surface density and thickness of the particle-fixed fiber sheet obtained by the production method of the present invention are not particularly limited, the surface density is preferably 3 to 650 g / m ² , and 4 to 550 g. / more preferably ^m is ^2, more preferably 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, fixing the amount of the solid particles is preferably from 0.1 to 200 g / ^{m 2,} more preferably from 0.2~180g / ^{m 2,} to be 0.3~150g / ^{m 2} more preferable.

  According to the production method of the present invention, since the heated solid particles are brought into contact with the fiber sheet containing the thermoplastic fiber, only the portion where the solid particles are in contact with the thermoplastic fiber surface is melted and solidified to fix the solid particles. ing. Therefore, it is very rare that the molten resin covers the surface portion of the solid particles other than the contact portion or the surface portion other than the fixed portion. 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 fixed, 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 fixed on the surface of the plastic fiber.

  Further, according to the production method of the present invention, since the solid particles melt only the surface of the thermoplastic fiber, even when the thermoplastic fiber is a fiber composed of a single resin component, it is heated during the contact treatment or the melt-solidification 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.

  Moreover, in the manufacturing method of this invention, since the heating airflow which has an airflow direction different from the airflow direction of the said particle-containing airflow is made to contact with the part in which a particle-containing airflow contacts the said fiber sheet, solid particles are ensured. There is an effect that it can be fixed. Moreover, there is an effect that the amount of solid particles fixed can be increased.

  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.

(Preparation of thermoplastic fiber sheet A)
A core-sheath type composite fiber (fiber diameter = 11 μm, fiber length = 5 mm) 100 in which the core component is polypropylene resin (melting point = 160 ° C.) and the sheath component is high-density polyethylene resin (melting point = 132 ° C.) by a papermaking apparatus. The papermaking sheet which consists of% was created. Next, the paper sheet is placed on a metal mesh conveyor net and heated at a temperature of 140 ° C. so that the high density polyethylene resin, which is an adhesive component of the composite fiber, melts in an air-through dryer. Adhesion treatment was performed to obtain a raw material roll of a wet method nonwoven fabric (thermoplastic fiber sheet A). This wet method nonwoven fabric had a thickness of 0.27 mm and an areal density of 50 g / m ² .

(Preparation of thermoplastic fiber sheet B)
Staple fiber 30 comprising a core-sheath type composite fiber (fiber diameter = 15 μm, fiber length = 51 mm) in which the core component is polypropylene resin (melting point = 160 ° C.) and the sheath component is high-density polyethylene resin (melting point = 132 ° C.). From mass%, a core-sheath composite fiber (fiber diameter = 21 μm, fiber length = 64 mm) whose core component is polypropylene resin (melting point = 160 ° C.) and whose sheath component is high-density polyethylene resin (melting point = 132 ° C.) 40% by mass of staple fibers, a core-sheath type composite fiber (fiber diameter = 15 μm, fiber length) in which the core component is a polyester resin (melting point = 264 ° C.) and the sheath component is a copolyester resin (melting point = 110 ° C.) = 52 mm) was mixed with 30% by mass of staple fibers, and a fiber web was formed using a carding machine. Subsequently, this fiber web was subjected to a heat bonding treatment with hot air at 150 ° C. using a hot air type dryer to obtain a raw material roll of a dry process nonwoven fabric (thermoplastic fiber sheet B). This dry nonwoven fabric had a thickness of 6.5 mm and an areal density of 180 g / m ² .

Example 1
In the manufacturing apparatus shown in FIG. 2, commercially available alumina particles (manufactured by Nippon Light Metal Co., Ltd., product number LS-210B, particle size D50: 3.2 μm) 29 are placed in the supply container 21, and the alumina particles are heated to 220 ° C. by the heater 51. Further, the heated alumina particles were supplied to the ejector 30 by the rotary supply control rotor 23. On the other hand, the air flow A heated to 130 ° C. generated in the blower 11 and the heating pipe 12 is sent to the ejector 30, and the alumina particles 29 supplied from the supply control rotor 23 are sucked by the suction force generated by the air flow A, and the air flow A Alumina particles-containing airflow D was formed by mixing alumina particles therein, and the alumina particle-containing airflow D was ejected from the nozzle 41. The nozzle 41 has a shape in which the tip of the nozzle is widened with respect to the root of the nozzle, and the nozzle has a slit shape.
In addition, as shown in FIG. 2, a nozzle 60 for ejecting the heated airflow E is provided in the region below the fiber sheet 80 and on the fiber sheet unwinding side with respect to the nozzle 41, and the direction of the heated airflow E is (lower fiber sheet 80, and the fiber sheet unwinding side from) from the lower right-alumina particles containing stream is set to point to the contact portion R _P in contact with the fiber sheet 80. In addition, the width | variety of the jet nozzle of the nozzle 60 has the same width as the nozzle 41, and the shape of a jet nozzle used the slit shape. The temperature of the heated airflow was set to 140 ° C.

Next, the thermoplastic fiber sheet A80 prepared in the above-mentioned (Preparation of thermoplastic fiber sheet A) is unwound from the raw material roll 81, passed under the conveyor net 71, passed under the nozzle 41, and the thermoplastic fiber sheet A80 is alumina. The particle-containing airflow D was sprayed to bring the alumina particle-containing airflow D into contact with the thermoplastic fiber sheet A80. At the same time, the heated airflow E was blown onto the thermoplastic fiber sheet A80 by using the nozzle 60 to bring the heated airflow E into contact with the thermoplastic fiber sheet A80. Note At this time, as the portion R _P alumina particle-containing stream D comes into contact with the thermoplastic fiber sheet A80, heated gas flow E is and the moiety R _H in contact with the thermoplastic fiber sheet A80 overlap to approximately 2/3 of the R _P Set to.
In this way, the high-density polyethylene resin, which is the sheath component of the core-sheath composite fiber constituting the thermoplastic fiber sheet A, is melted by the heated alumina particles, and the alumina particles are fused to the surface of the core-sheath composite fiber. Thus, a particle fixed fiber sheet was formed. Excess alumina particles that were not fused to the thermoplastic fiber sheet A during the spraying of the alumina particle-containing air flow D were collected by suction by a particle collection box 91 disposed under the conveyor net 71. Furthermore, surplus alumina particles that did not adhere to the thermoplastic fiber sheet A were blown off using the blower 92 and the air nozzle 93, and surplus alumina particles were recovered by suction boxes 94 and 95 provided above and below the conveyor net 71. Thereafter, the particle fixed fiber sheet was wound up as a winding roll 82.
The surface density of the obtained particle fixed fiber sheet was 73.7 g / m ² , the thickness was 0.29 mm, and the fixed alumina particles were 23.7 g / m ² . Moreover, the electron micrograph of the surface (surface to which the alumina particle containing airflow D was sprayed) of this particle fixed fiber sheet is shown in FIG. Moreover, the electron micrograph of the back surface (surface to which the heating airflow E was sprayed) of this particle fixed fiber sheet is shown in FIG.

(Examples 2 to 4)
In Example 1, the temperature of the heated air stream E was set to 130 ° C. (Example 2), 128 ° C. (Example 3), and 125 ° C. (Example 4), respectively. A fixed fiber sheet was obtained.
The resulting surface density of the particles adhered fiber sheet respectively 73.1 g / ^{m 2} (Example ^2), 67.5g / ^m 2 (Example 3), was 64.9 g / ^{m 2} (Example 4), The thicknesses were 0.29 mm (Example 2), 0.28 mm (Example 3), and 0.28 mm (Example 4), respectively, and the fixed alumina particles were 23.1 g / m ² (Example 2), respectively. 17.5 g / m ² (Example 3) and 14.9 g / m ² (Example 4). Further, the electron micrographs of the surfaces of these particle-fixed fiber sheets (the surface on which the alumina particle-containing air flow D was sprayed) were the same as those in FIG. Moreover, the electron micrograph of the back surface (surface to which the heating airflow E was sprayed) of these particle fixed fiber sheets is shown in FIG. 6 (Example 2) and FIG. 7 (Example 4).

(Comparative Example 1)
In Example 1, a particle-fixed fiber sheet was obtained in the same manner as in Example 1 except that the heated airflow E was not blown onto the thermoplastic fiber sheet A80 without using the nozzle 60.
The surface density of the obtained particle fixed fiber sheet was 63.6 g / m ² , the thickness was 0.28 mm, and the fixed alumina particles were 13.6 g / m ² . Further, the electron micrograph of the surface of the particle-fixed fiber sheet (the surface on which the alumina particle-containing air flow D was sprayed) was the same as FIG. Moreover, the electron micrograph of the back surface (surface opposite to the surface where the alumina particle containing airflow D was sprayed) of this particle fixed fiber sheet is shown in FIG.

According to the manufacturing methods of Examples 1 to 4, the heated air stream having an air flow direction different from the air flow direction of the alumina particle-containing air flow D with respect to the portion _{RP in} which the alumina particle-containing air flow D is in contact with the thermoplastic fiber sheet A. Whereas E is in contact, in Comparative Example 1, the heated airflow E is not in contact. As a result, the fixed amount of alumina particles in the particle-fixed fiber sheets obtained by the production methods of Examples 1 to 4 is that of Comparative Example 1 as can be seen from the data on the fixed amount and the photograph on the back side of the particle-fixed fiber sheet. It turns out that it is larger than the fixed amount of the alumina particle of the particle fixed fiber sheet obtained by the manufacturing method.

(Example 5)
In Example 1, instead of the thermoplastic fiber sheet A, the thermoplastic fiber sheet B prepared in the above (Preparation of thermoplastic fiber sheet B) was used, and commercially available alumina particles (manufactured by Nippon Light Metal Co., Ltd., product number LS) Particle fixing fiber in the same manner as in Example 1 except that alumina particles (manufactured by Nippon Light Metal Co., Ltd., product number A34, particle size D50: 4.4 μm) were used instead of -210B, particle size D50: 3.2 μm). A sheet was obtained.
The surface density of the obtained particle fixed fiber sheet was 186.4 g / m ² , the thickness was 6.5 mm, and the fixed alumina particles were 6.4 g / m ² . Moreover, the electron micrograph of the surface (surface to which the alumina particle containing airflow D was sprayed) of this particle fixed fiber sheet is shown in FIG. Moreover, the electron micrograph of the back surface (surface to which the heating airflow E was sprayed) of this particle fixed fiber sheet is shown in FIG.

(Examples 6 to 7)
In Example 5, the particle fixed fiber sheet was obtained like Example 5 except having set the temperature of the heating airflow E to 130 degreeC (Example 6) and 123 degreeC (Example 7), respectively.
The surface density of the obtained particle fixed fiber sheet is 186.1 g / m ² (Example 6) and 184.8 g / m ² (Example 7), respectively, and the thickness is 6.5 mm (Example 6). 6.5 mm (Example 7), and the fixed alumina particles were 6.1 g / m ² (Example 6) and 4.8 g / m ² (Example 7), respectively. Further, the electron micrographs of the surfaces of these particle-fixed fiber sheets (the surface on which the alumina particle-containing air flow D was sprayed) were the same as those in FIG. Further, FIG. 11 (Example 8) and FIG. 12 (Example 9) show electron micrographs of the back surfaces (surfaces to which the heated airflow E is blown) of these particle-fixed fiber sheets.

(Comparative Example 2)
In Example 5, a particle-fixed fiber sheet was obtained in the same manner as in Example 5 except that the heated airflow E was not sprayed onto the thermoplastic fiber sheet B80 without using the nozzle 60.
The surface density of the obtained particle fixed fiber sheet was 184.6 g / m ² , the thickness was 6.5 mm, and the fixed alumina particles were 4.6 g / m ² . Further, the electron micrograph of the surface of the particle-fixed fiber sheet (the surface on which the alumina particle-containing air flow D was sprayed) was the same as FIG. Moreover, the electron micrograph of the back surface (opposite surface to which the alumina particle containing airflow D was sprayed) of this particle fixed fiber sheet is shown in FIG.

According to the production method of Example 5-7, with respect to the portion R _P alumina particle-containing stream D is in contact with the thermoplastic fiber sheet B, having different air flow direction to the airflow direction of the alumina particle-containing stream D Whereas the heated airflow E is in contact, in Comparative Example 2, the heated airflow E is not in contact. As a result, the fixed amount of alumina particles of the particle-fixed fiber sheets obtained by the production methods of Examples 5 to 7 is that of Comparative Example 2 as can be seen from the data on the fixed amount and the photograph on the back side of the particle-fixed fiber sheet. It turns out that it is larger than the fixed amount of the alumina particle of the particle fixed fiber sheet obtained by the manufacturing method.

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, alumina particle 30 Particle mixing means, ejector 31 Part 40 to which heated solid particle is supplied 40 Ejection means 41 Nozzle 50 , 51, 52, 53, 55 Heating means, heater 60 heating airflow ejection means, nozzles 61, 62, 63, 64 heating airflow ejection means, nozzle 70 rotating roll or fiber sheet support means 71 conveyor net or fiber sheet support means 80 ( Thermoplastic) Fiber sheet 81 Raw material roll 82 Winding roll 91 Particle recovery box 92 Blower 93 Air nozzle 94, 95 Suction box

Claims (1)

A method for producing a particle-fixed fiber sheet, in which solid particles having a melting point or decomposition temperature higher than the melting point of the thermoplastic resin are fixed to a fiber sheet containing thermoplastic fibers having at least a surface made of a thermoplastic resin,
When the particle-containing airflow containing the solid particles having a temperature higher than the melting point of the thermoplastic resin is brought into contact with the fiber sheet, the thermoplastic resin is melted and solidified to fix the solid particles to the fiber sheet. A method for producing a particle-fixed fiber sheet, wherein a heating airflow having an airflow direction different from the airflow direction of the particle-containing airflow is brought into contact with a portion where the particle-containing airflow is in contact with the fiber sheet.

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