JP2001040563A - Production of mixed fiber mat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a mixed fiber mat without mixing fiber masses therein when forming the mixed fiber mat. SOLUTION: This method for producing a mixed fiber mat 43 comprises installing a reticulate net 32 near the lower side of each opening roll 31 in an opening part for opening a mixed fibrous material 40 and uniformizing the mixed fibrous material 40, making fiber masses 44 having a high specific gravity sticking to the opening roll 31 stick to the reticulate net 32 and removing the fiber masses 44 through a brush roll 33, a sucking machine 34 or compressed air 35 while rotating the reticulate net 32 in the method for producing the mixed fiber mat 43 comprising opening the mixed fibrous material 40 of reinforcing fibers 41 with thermoplastic resin fibers 42, providing uniform mixed fibers, conveying the mixed fibers onto a belt with an air stream and integrating the mixed fibers by needling, or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mixed fiber in which a mixed fiber material of a reinforcing fiber and a thermoplastic resin fiber is defibrated into a uniform mixed fiber, conveyed on a belt by an air flow, and integrated by needling or the like. The present invention relates to a method for manufacturing a mat.

[0002]

2. Description of the Related Art The prior art will be described with reference to FIGS. 1 and 6 using the same reference numerals as those used in the conventional apparatus for manufacturing a mixed fiber mat and the apparatus for forming a fiber-reinforced thermoplastic sheet.

[0003] That is, as shown in FIG.
The mixed fiber mat 43 formed by the needling 24 from the mixed fiber material 40 of 1 and the thermoplastic resin fiber 42 is:
As shown in FIG. 6, a fiber-reinforced thermoplastic sheet 60 is formed by applying heat and pressure, and this sheet 60 is used as a core material or a stamping material for extrusion molding.

Japanese Patent Application Laid-Open (JP-A) No. 62-207605 discloses a mat forming process, and Japanese Patent Application Laid-Open (JP-A) No. 1-1160 discloses a fiber-reinforced thermoplastic sheet forming process.

In the method of manufacturing the mixed fiber mat 43, in the step of defibrating the mixed fiber material 40, the fiber mass 44 adheres to the defibrating roll 31, and the adhered fiber mass 44 is formed in the mixed fiber mat 43. And the mixed fiber mat 43 having the fiber mass 44 locally is formed.

[0006]

However, when the mixed fiber mat 43 is formed on the fiber reinforced thermoplastic sheet 60 by the conventionally used fiber reinforced thermoplastic sheet forming apparatus shown in FIG. When 60 is used as a core material in extrusion molding, the locally existing fiber mass 44 is easily broken, and if broken, the production process is disturbed and it takes time to readjust, so that there is a problem that the cost increases. Was.

Therefore, an object of the present invention is to provide a method for producing a mixed fiber mat in which a lump of fibers is not mixed during molding of the mixed fiber mat.

[0008]

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention according to claim 1 is to provide a method of defibrating a mixed fiber material of a reinforcing fiber and a thermoplastic resin fiber into a uniform mixed fiber to form an air flow. In the method for producing a mixed fiber mat which is conveyed on a belt and integrated by needling or the like, a mesh net is provided near a lower part of a defibrating roll of a defibrating section for defibrating and uniformizing the mixed fiber material, A mass of fibers having a specific gravity attached to the fiber roll is attached to the mesh-like net, and while rotating the mesh-like net, the fiber mass is peeled off and removed via a brush roll. I have.

In such a device, since a rotatable mesh net is provided, a lump of fibers is adhered to the mesh net, rotated, separated by a brush roll, and dropped to a receiving portion. become.

Here, the mixed fiber material refers to a mixture of the following thermoplastic resin fiber and reinforcing fiber.

That is, the thermoplastic resin fiber is a thermoplastic resin that is processed into a fibrous form from the beginning, such as olefin resins such as polyethylene (PE) and polypropylene (PP), polyamide (PA), and acrylonitrile (PMM).
A), polyethylene terephthalate (PET) and the like, and olefin resins such as PE and PP as powders;
Polyvinyl chloride (PVC), polystyrene (PS),
In addition to PA, polycarbonate (PC), polyphenylene sulfide (PPS), polysulfone (PSU), polyetheretherketone (PEEK), and the like, a thermoplastic elastomer (TPE) can be used.

The above-mentioned thermoplastic resins may be used alone or in combination, and may be a heat stabilizer, a plasticizer, a lubricant, an antioxidant, an ultraviolet absorber, a pigment, an inorganic filler, a reinforcing single fiber, or the like. , A filler, a processing aid, a modifier and the like may be added.

Further, the reinforcing fibers are those which are thermally stable at the melting temperature of the thermoplastic resin shown below.

That is, inorganic fibers such as glass fiber, carbon fiber, and ceramic fiber, organic fibers such as PA fiber and PES fiber, and metal fibers are listed.
It refers to fibers of 0 GPa or more.

The diameter of the fiber monofilament is
It is preferably from 1 to 50 μm, particularly preferably from 2 to 30 μm.

According to a second aspect of the present invention, in the method for producing a mixed fiber mat, a mesh net is provided near a lower portion of a defibrating roll of a defibrating section for defibrating and uniformizing the mixed fiber material. A mass of fibers having a specific gravity attached to a roll is attached to the mesh net, and while rotating the mesh net, the mass of the fibers is suctioned and removed via a suction machine, and the mass is removed. I have.

In such a device, since a rotatable mesh net is provided, a lump of fibers is attached and rotated to the reticulated net, and the lump of fibers is sucked while being dispersed by a suction machine. You.

According to a third aspect of the present invention, in the method for producing a mixed fiber mat, a mesh net is provided near a lower portion of a defibrating roll of a defibrating section for defibrating and uniformizing the mixed fiber material. A mass of fibers having a high specific gravity attached to a roll is attached to the mesh net, and while rotating the mesh net, the mass of fibers is blown off via compressed air to remove the mass. I have.

In such a device, since a rotating mesh net is provided, the fiber mass is adhered and rotated to the mesh net, and is blown off by compressed air, and the fiber mass is removed by the receiving portion. Can be dropped.

The invention described in claim 4 is based on claim 1,
The method for producing a mixed fiber mat according to 2 or 3,
The mesh net can be rotated in a vertical direction or a horizontal direction.

In such a structure, the mesh net can be rotated in the vertical direction or the horizontal direction, so that the lump of the falling fibers is easily adhered to the mesh net. It can approach the air.

According to a fifth aspect of the present invention, in the method for producing a mixed fiber mat according to the first or third aspect, the fiber mass removed from the rotating mesh net by a brush roll or compressed air is: It is characterized in that a receiving portion having a mass removing means is provided.

In such a case, since the lump removing means is provided in the receiving portion, the lump of fibers can be removed from the receiving portion to the outside.

According to a sixth aspect of the present invention, in the method of manufacturing a mixed fiber mat according to the fifth aspect, the mass removing means includes a screw provided in a receiving portion, and a mass receiving box is subsequently provided. It is characterized by.

In such a case, since the screw is provided in the receiving portion, the fiber mass can be removed by the screw and collected in the subsequent mass receiving box. Therefore, continuous operation can be performed for a long time.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for producing a mixed fiber mat using a conventionally used apparatus for producing a mixed fiber mat according to the present invention will be described with reference to FIG.

FIG. 1 is an explanatory view showing a method for producing a mixed fiber mat.

In FIG. 1, reference numeral 20 denotes an apparatus for producing a mixed fiber mat, 21 and 211 denote left and right supply conveyors,
The mixed fiber material 40 is supplied from the left and right hoppers into the left and right defibrating units 30 and 301.

Then, the defibrated mixed fiber material 40 is
The mixed fiber mats 43, 43 in the form of mats are formed on the conveyors 22, 221 by air flow, and are separately conveyed and stacked on the left and right conveyors 22, 221 and pressurized to a thickness of about 1/2. This shows a method of manufacturing a mixed fiber mat which is formed by pressing the roll 23 and then integrally entangled by a needling 24 to form a mixed fiber mat 43 having a predetermined thickness and length, and winding the same by a mat winder 25. .

Then, the productivity is reduced during the production of the mixed fiber mat 43 (

An embodiment of a method for removing the fiber mass 44, which has been generated without breaking at the defibrating units 30 and 301, will be described below.

[Embodiment 1] FIG. 2 is an explanatory view of a part A of FIG. 1 showing a method of removing a lump of fibers according to Embodiment 1.

In FIG. 2, reference numeral 30 denotes a defibrating unit, 31 denotes a set of defibrating rolls, and each defibrating roll 31 has a needle-like projection 31a. And this one set of defibrating rolls 31 is a large-diameter roll a,
c, d, e, and f wrap around half way, as indicated by the arrow,
The mixed fiber material 40 is configured to move while being defibrated between the needle-like projections 31a of each defibrating roll that rotates.

Reference numeral 44 denotes a set of fibers formed in the defibrated mixed fiber material 40 without defibration, 32 denotes a mesh net provided near the lower portion of the defibration roll 31, and 33 denotes a mesh net. A brush roll 45 is provided in the vicinity of the lower end of the tip 32. Reference numeral 45 denotes a receiving portion of the fiber mass 44, and the mesh net 32 is installed at a position where the air flow is not changed.

The mesh net 32 installed in the air flow is adjusted according to the position where the fiber mass 44 falls.
It can be rotated in any suitable direction, such as vertical or horizontal. Further, as shown by the arrow, the brush roll 33 is
5 is rotated.

Accordingly, the mixed fiber material 40 discharged from the defibrating roll 31 and defibrated is blown toward the conveyors 22 and 221 by the air flow, but the fiber mass 44 has a high specific gravity and a mesh density. Drops on the net and adheres.

The fiber mass 44 is moved downward by the rotating mesh net 32 as shown by the arrow, peeled off from the mesh net 32 by the rotating brush roll 33, and Drop it and remove it.

(Modification) FIG. 5 is an explanatory view showing a modification of the receiving portion.

In FIG. 5, reference numeral 451 denotes a modified example of the receiving portion;
45 is a screw, 47 is a lump receiving box.

Therefore, the fiber mass 4 that has fallen
4 enters the screw part 46 from the hopper 45a, moves by the screw part 46 rotating as shown by the arrow, and
5b, and is collected by the mass receiving box 47 having a large capacity.

[Embodiment 2] FIG. 3 is an explanatory view of a part A of FIG. 1 showing a method for removing fiber clumps according to Embodiment 2.

In FIG. 3, reference numeral 34 denotes a suction machine.

Therefore, the fiber mass 44 attached to the mesh net 32 is moved downward by the rotating mesh net 32 as shown by the arrow, and the fiber mass 44 is moved by the suction device into the mesh net 32. It is aspirated from and removed.

Other configurations and operations are the same as those of the first embodiment, and therefore the description thereof is omitted.

[Embodiment 3] FIG. 4 is an explanatory view of a portion A of FIG. 1 showing a method for removing a lump of fibers according to Embodiment 3.

In FIG. 4, reference numeral 35 denotes compressed air.

Accordingly, the fiber mass 44 attached to the mesh net 32 is moved downward by the rotating mesh net 32, as indicated by the arrow, and the fiber mass 44 is moved by the compressed air 35 into the mesh net. It is blown away from 32 and dropped into the receiving portion 45 to be removed.

Other configurations and operations are the same as those of the first embodiment, and therefore, description thereof will be omitted.

[0048]

EXAMPLES Using the above-described apparatus for producing a mixed fiber mat,
A mixed fiber mat is formed by using the method of Embodiment 1, 2 or 3 for removing a lump of fibers (using a mesh net), and the mixed fiber mat is formed into fibers by using a fiber reinforced thermoplastic sheet forming apparatus. Formed into a reinforced thermoplastic sheet and then extruded using this sheet as a core material, comparing the presence or absence of breakage with a mixed fiber mat that did not use the conventional method of removing fiber clumps (without using a mesh net) did.

It was confirmed that the fiber using the method of removing fiber lump had improved quality and did not break. (1) Content of the mixed fiber mat (by the mixed fiber mat manufacturing equipment) Contents ● Reinforcement fiber used ・ Carbon fiber (CF) with a diameter of 10 μm and an average length of about 50 mm and P with a diameter of about 20 μm and an average length of about 50 mm
Using ET (melting temperature: 255 ° C.) fiber, the fibers were entangled with each other by needling.

● Specifications of the mixed fiber mat: The formation speed of the mixed fiber mat was 3 m / min. The obtained mixed fiber mat had a basis weight of about 450 g / m ² and CF: PE.
At T = 30: 70 (wt%), the predetermined thickness of the mixed fiber mat was 7 mm on average.

Length: A 500 m mixed fiber mat wound around a paper core. (2) Forming a mixed fiber mat into a sheet (using a fiber-reinforced thermoplastic sheet forming device) ● Molding conditions for a fiber-reinforced thermoplastic sheet manufacturing device ・ Heating furnace Heater: Far-infrared heater Atmospheric temperature of mat passage in furnace: 285 ° C ・ Heating roll Roll surface temperature: 100 ° C Roll diameter: 250mm Roll pressure: 50 kgf / cm at linear pressure ・ Cooling roll Roll surface temperature: 30 ° C Roll diameter: 250mm Roll pressure: 50 kgf / cm at linear pressure ・ Fiber reinforced heat Molding of plastic sheet Line speed: 1.5 m / min (width: 500 mm) (3) Comparative results ● Under the above-mentioned reinforcing fiber and molding conditions, polyvinyl chloride resin was applied to the two types of fiber-reinforced thermoplastic sheets obtained. The number of breaks of the fiber-reinforced thermoplastic sheet during extrusion coating and extrusion was examined.

Results: <Number of times of breakage during extrusion>-Fiber with lump removed: 0 times / 500 m-Fiber without lump: 2 times / 500 m

[0053]

According to the present invention, the quality is improved by removing the fiber clumps by using a mesh net in the defibrating section, and even if the sheet is converted from a mat shape and used as a core material of an extruded product,
No break occurred. Therefore, the defect rate is reduced, and the cost can be reduced.

Further, since the screw is mounted on the fiber mass receiving portion, the fiber mass can be collected at any time, and the productivity is improved.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an example of a method for producing a mixed fiber mat according to the present invention.

FIG. 2 is an explanatory view of a part A of FIG. 1 showing a method for removing a fiber lump in the first embodiment according to the present invention.

FIG. 3 is an explanatory view of a part A of FIG. 1 showing a method of removing a fiber lump in a second embodiment according to the present invention.

FIG. 4 is an explanatory view of a portion A in FIG. 1 showing a method of removing a fiber lump in a third embodiment according to the present invention.

FIG. 5 is an explanatory view showing a modified example of a fiber mass receiving portion according to the present invention.

FIG. 6 is an explanatory view showing a conventionally used apparatus for forming a fiber-reinforced thermoplastic sheet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 31 ... Fibrillation roll 32 ... Mesh net 33 ... Brush roll 34 ... Suction machine 35 ... Compressed air 40 ... Mixed fiber material 41 ... Reinforcing fiber 42 ... Thermoplastic resin fiber 43 ... Mixed fiber mat 44 ... Fiber lump

Claims (6)

[Claims] 1. A method for producing a mixed fiber mat in which a mixed fiber material of reinforced fibers and thermoplastic resin fibers is defibrated into uniform mixed fibers, conveyed on a belt by air flow, and integrated by needling or the like. A mesh net is provided in the vicinity of the lower part of the defibrating roll of the defibrating unit for defibrating and homogenizing the mixed fiber material, and a mass of fibers having a high specific gravity attached to the defibrating roll is adhered to the mesh net. A method for producing a mixed fiber mat, wherein the fiber mass is peeled off and removed via a brush roll while rotating the net. 2. A mesh net is provided in the vicinity of a lower part of a defibrating roll of a defibrating unit for defibrating and homogenizing a mixed fiber material, and a mass of fibers having a high specific gravity attached to the defibrating roll is transferred to the mesh net. A method of manufacturing a mixed fiber mat, wherein the fiber mass is sucked and removed via a suction machine while attaching and rotating the mesh net. 3. A mesh net is provided in the vicinity of a lower portion of a defibrating roll of a defibrating section for defibrating and homogenizing a mixed fiber material, and a mass of fibers having a high specific gravity attached to the defibrating roll is transferred to the mesh net. A method for producing a mixed fiber mat, wherein the fiber mass is blown off and removed via compressed air while attaching and rotating the mesh net. 4. The method according to claim 1, wherein the mesh net is rotatable in a vertical direction or a horizontal direction. 5. The mixing according to claim 1, further comprising a receiving portion having a lump removing means for removing the lump of the fibers removed from the rotating mesh net by a brush roll or compressed air. Manufacturing method of fiber mat. 6. The method for producing a mixed fiber mat according to claim 5, wherein the mass removing means includes a screw provided in a receiving portion, and a mass receiving box is subsequently provided.