JP2005342902A - Fiber reinforced thermoplastic sheet and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fiber reinforced thermoplastic sheet wherein a surface sheet can be simply and uniformly laminated on a core sheet without shrinking the surface sheet, and its manufacturing method. <P>SOLUTION: The fiber reinforced thermoplastic sheet is composed of the core sheet 2 formed from a fiber mixture of reinforcing fibers and resin fibers and the surface sheet 4 low in basis weight and formed by bonding the surface sheet 4 to the surface of the core sheet 2 under heating and pressure. This fiber reinforced thermoplastic sheet is integrally formed by bonding the surface sheet 4 on the core sheet 2, of which the surface is melted, under heating and pressure and cooling the bonded sheets. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a fiber-reinforced thermoplastic sheet obtained by heat-pressing a surface sheet with a small basis weight on the surface of a core sheet formed from a mixed fiber of reinforcing fibers and thermoplastic resin fibers, and a method for producing the same.

Conventionally, as a fiber reinforced thermoplastic sheet, one formed by thermocompression bonding a thermoplastic sheet such as a PET resin to the surface of a core sheet formed from a mixed fiber of reinforced fibers and thermoplastic resin fibers is known. (For example, refer to Patent Document 1).

In addition, after the two stacked sheets are heated and melted in a heating furnace, the two sheets are pressed with a thermocompression-bonding roll, and then cooled with a cooling roll to form a fiber-reinforced thermoplastic sheet. It was.
JP 2000-141523 A

However, if more heat than necessary is applied to the surface sheet, a normal film is used as the surface sheet as the surface layer, so the surface sheet shrinks (shrinks), and the core sheet is made uniform with the surface sheet. There was a problem of being unable to laminate.

Moreover, in order to eliminate this, when the heating apparatus only for a surface sheet was installed and the heating process only for a surface sheet was performed, there existed a problem that an installation became larger than needed.

Therefore, an object of the present invention is to provide a fiber-reinforced thermoplastic sheet and a method for producing the same, in which the core sheet can be easily and uniformly laminated with the surface sheet without shrinking (shrinking) the surface sheet.

In order to achieve this object, the invention of claim 1 includes a core sheet formed from a mixed fiber of reinforcing fibers and thermoplastic resin fibers, and a surface sheet with a small basis weight, and the surface sheet is provided on the surface of the core sheet. It is a fiber reinforced thermoplastic sheet formed by thermocompression bonding, wherein the surface sheet is thermocompression bonded to the core sheet whose surface has been melted, and is formed integrally by cooling.

In order to achieve the above-described object, the invention according to claim 2 is characterized in that both sheets in the state in which a surface sheet with a small basis weight is superimposed on the surface of a core sheet formed from a mixed fiber of reinforcing fibers and thermoplastic resin fibers. Is a method for producing a fiber-reinforced thermoplastic sheet that is heated and pressure-bonded between a pair of thermo-compression rollers while being fed, after the core sheet is sent to a heating furnace to melt the surface, from the heating furnace The top sheet is overlapped on the core sheet to be sent out and fed between the thermocompression-bonding rollers, and both the fed sheets are thermocompression-bonded between the thermocompression-bonding rollers.

Further, the invention of claim 3 is the invention according to claim 2, wherein a plurality of sets of the one-to-one set of thermocompression-bonding rollers are arranged in the feeding direction of both sheets, and the plurality of sets of thermo-compression-bonding rollers feed the both sheets. The heating temperature is set to be sequentially lower as it goes in the direction.

According to invention of Claim 1 mentioned above, since it is set as the structure formed integrally by heat-pressing and cooling the said surface sheet to the said core sheet by which the surface was fuse | melted, a surface sheet shrinks (shrinks). In addition, a fiber reinforced thermoplastic sheet in which the core sheet is simply and uniformly laminated with the surface sheet can be formed.

Further, according to the invention of claim 2, after the core sheet is sent to a heating furnace to melt the surface,
Since the top sheet is overlapped on the core sheet fed from the heating furnace and sent between the thermocompression-bonding rollers, both the fed sheets are thermocompression-bonded between the thermocompression-bonding rollers. A fiber-reinforced thermoplastic sheet in which a core sheet is simply and uniformly laminated can be formed.

Furthermore, according to the invention of claim 3, both sheets can be gradually cooled by the plurality of sets of thermocompression-bonding rollers. As a result, the core sheet can be uniformly and reliably laminated with the top sheet by cooling the top sheet so as not to be distorted.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Constitution]
FIG. 1 shows a manufacturing apparatus (manufacturing system) for manufacturing a fiber-reinforced thermoplastic sheet according to the present invention.
Is shown.

In FIG. 1, 1 is a heating furnace, 2 is a core sheet (mixed mat) supplied from a sheet roll (mat roll) (not shown), 3 is a sheet roller disposed adjacent to the heating furnace 1,
4 is a surface sheet with a small basis weight fed from the sheet roller 3, 5 is a thermocompression roller group (heated pinch roll group) that heat-presses the core sheet 2 and the surface sheet 4, and 6 is a cooling roller (
A cooling pinch roll (7) is a sheet take-up roller (winding stand or take-up device).

The atmospheric temperature in the heating furnace 1 described above is set to 280 ° to 320 ° C. The core sheet 2 is a mixed mat (nonwoven fabric) formed in a sheet shape from a mixed fiber of reinforcing fibers and thermoplastic resin fibers. As this mixing mat, JP-A 2000-141
Since a mat formed by a mat forming apparatus as disclosed in Japanese Patent No. 523 can be used, detailed description thereof is omitted.

Furthermore, a nonwoven fabric made of a thermoplastic resin with a small basis weight can be used for the top sheet 4. In this example, the same type of PET as the thermoplastic resin fibers of the core sheet 2 as the top sheet 4
A resin resin having a basis weight of 15 g / m ² was used.

The thermocompression roller group 5 includes a pair of first thermocompression rollers 5a and 5a, a pair of second thermocompression rollers 5b and 5b, and a pair of third thermocompression rollers 5c and 5c. Have. The thermocompression rollers 5a, 5b, and 5c have a roll diameter of 250 mm, and the surface temperature of the thermocompression rollers 5a, 5b, and 5c can be set (adjusted) in a range of 100 ° to 160 ° C. ing.

Moreover, the heating pinch pressure between the first thermocompression rollers 5a and 5a, the second thermocompression roller 5b,
The heating pinch pressure between 5b and the heating pinch pressure between the third thermocompression-bonding rollers 5c, 5c are 6 to 6 in terms of linear pressure.
It is set to 14 Mpa.

The cooling rollers 6 and 6 have a roll diameter of 250 mm, and the cooling rollers 6 and 6
The surface temperature of is set to 30 ° C. The cooling pressure of the cooling rollers 6 and 6 is 6 to 6 as linear pressure.
It is set to 8 Mpa.

Further, in this embodiment, the top sheet 4 is brought into close contact with the lower side of the core sheet 2, but the top sheet 4 may be brought into close contact with the upper side of the core sheet 2, and the top sheet 4 is made of the core sheet. The two surfaces (upper and lower surfaces) may be in close contact with each other.

The line feed speed when the sheets 2 and 4 are wound by the sheet winding roller 7 is 7.0 to 8.
. It is set to 5 m / min.
[Action]
Next, the operation of the apparatus for producing a fiber-reinforced thermoplastic sheet having such a configuration will be described.

The core sheet 2 formed from the mixed fiber of the reinforcing fiber and the thermoplastic resin fiber is fed out from a sheet roll (not shown), and the inside ambient temperature of the fed core sheet 2 is 280 ° to 320 °.
The fiber sheet of the core sheet 2 is melted in the heating furnace 1 at ° C, and the core sheet 2 having the melted surface is supplied from the heating furnace 1 to the heat press roller group 5 side. .

On the other hand, the top sheet 4 having a small basis weight is fed out from the sheet roller 3, and the fed out top sheet 4 is placed along the surface of the core sheet 2 supplied from the heating furnace 1 to the first thermocompression-bonding rollers 5 a and 5 a (see FIG. 2) (corresponding to No. 1 roll of No. 2).

At this time, the pinch pressure of the first thermocompression-bonding rollers 5a and 5a was tested at either 11 Mpa or 13 Mpa shown in “No. 1 roll nonwoven fabric present” in FIG. At this time, the heating temperature of the sheets 2 and 4 by the first thermocompression rollers 5a and 5a, that is, the first thermocompression roller 5a and
The surface temperature of 5a is 120 ° C., 13 as shown by “No. 1 roll non-woven” in FIG.
The test was changed to 0 °, C140 ° C, and 160 ° C.

Then, the thermocompression-bonded sheets 2 and 4 are further connected to second thermocompression-bonding rollers 5b and 5b (FIG. 2).
And the third thermocompression-bonding rollers 5c and 5c (corresponding to the No3 roll of FIG. 2), and then supplied to the cooling rollers 6 and 6, respectively.

The pinch pressure (pressing force) between the second thermocompression-bonding rollers 5b and 5b is 13 Mpa under fixed conditions.
The pinch pressure (pressing force) between the third thermocompression-bonding rollers 5c and 5c is 8 MPa under fixed conditions.

Further, the surface temperature (heating temperature) of the second thermocompression roller 5b, 5b is 120 ° C. shown in the “No. 2 roll fixing condition” in FIG. 2, and the surface temperature (heating temperature) of the third thermocompression roller 5c, 5c. Is 100 ° C. shown in “No. 3 roll fixing conditions” in FIG.

Then, the cooling rollers 6 and 6 pressurize and cool both the sheets 2 and 4 which are heated and pressed by the third heating and pressing rollers 5c and 5c at a surface temperature of 30 ° C. and a linear pressure of 6 to 8 Mpa. The pressure-cooled sheets 2 and 4 are wound around a sheet winding roller 7 as a fiber-reinforced thermoplastic sheet 8 containing nonwoven fabric.

The properties such as the uniformity and fusing property of the surface sheet in the fiber-reinforced thermoplastic sheet produced in this way are as follows when the pinch pressure and the heating temperature by the first heat pressing rollers 5a and 5a are changed as described above. The following results were obtained.
<Uniformity>
That is, in the case of “No 1 roll non-woven fabric” in FIG. 2, the uniformity of the adhesion of the top sheet 4 to the core sheet 2 is that the first thermocompression roller 5a, 5a has a pinch pressure of 11 Mpa and the first thermocompression roller When the surface temperature of 5a, 5a is 130 °, and the pinch pressure of the first thermocompression roller 5a, 5a is 13Mpa, the surface temperature of the first thermocompression roller 5a, 5a is 120 ° C, 130 °
, C140 ° C and 160 ° C were all good.

On the other hand, when the surface sheet and the core sheet were heated and fused in a heating furnace, the uniformity of the surface sheet was poor as shown in “Heating in heating furnace” in FIG.

Furthermore, when a non-woven fabric is not used, the pinch pressure is 11 Mp as shown in FIG.
When the temperature at the time of thermocompression bonding was 130 ° C. in a, the uniformity of the surface sheet could not be confirmed.
<Sheet fusing property>
Further, the fusing property between the sheets 2 and 4 is the first in the case of “No 1 roll non-woven fabric” in FIG.
It was defective when the pinch pressure of the thermocompression rollers 5a, 5a was 11 MPa and the surface temperature of the first thermocompression rollers 5a, 5a was 130 ° C. Also, the adhesiveness between the sheets 2 and 4 is shown in FIG.
In the case of “No1 roll nonwoven fabric is present”, the pinch pressure of the first heat press roller 5a, 5a is 13
When the surface temperature of the first thermocompression roller 5a, 5a was 120 ° C. at Mpa, it was defective.

On the other hand, the fusing property between the sheets 2 and 4 is the first thermocompression roller when the pinch pressure of the first thermocompression rollers 5a and 5a is 13 Mpa in the case of “No1 roll nonwoven fabric” in FIG. The surface temperatures of 5a and 5a were slightly good at 130 °, and the surface temperatures of the first thermocompression roller 5a and 5a were good at C140 ° C and 160 ° C.
<Sheet strength>
Further, the strength of the sheets 2 and 4 is 31.8 N / cm when the surface temperature of the first thermocompression rollers 5a and 5a is 130 °, and the surface temperature of the first thermocompression rollers 5a and 5a is C140 ° C and 1
It was 41.6 N / cm at 60 ° C.

As described above, the fiber-reinforced thermoplastic sheet according to the embodiment of the present invention includes the core sheet 2 formed from the mixed fiber of the reinforcing fiber and the thermoplastic resin fiber, and the surface sheet 4 having a small basis weight.
The surface sheet 4 is formed on the surface of the core sheet 2 by thermocompression bonding. In addition, the fiber reinforced thermoplastic sheet is integrally formed by cooling the surface sheet 4 by thermocompression bonding to the core sheet 2 whose surface is melted.

According to this configuration, since the surface sheet 4 is integrally formed by thermocompression bonding and cooling to the core sheet 2 whose surface has been melted, the surface sheet does not shrink (shrink), A fiber-reinforced thermoplastic sheet obtained by simply and uniformly laminating the core sheet 2 with the sheet 4 can be formed.

Further, in the method for producing a thermoplastic sheet according to an embodiment of the present invention, the surface sheet 4 having a small basis weight is overlaid on the surface of the core sheet 2 formed from a mixed fiber of reinforcing fibers and thermoplastic resin fibers. A pair of thermocompression-bonding rollers (5a, 5a, 5b,
5b, 5c, 5c). And in this manufacturing method of a fiber reinforced thermoplastic sheet, after sending the said core sheet 2 to the heating furnace 1 and fuse | melting the surface, the said top sheet 4 is piled up on the said core sheet 2 sent out from the said heating furnace 1. The thermocompression roller (
5a, 5a, 5b, 5b, 5c, 5c), and the two sheets fed are thermocompression bonded between the thermocompression-bonding rollers (5a, 5a, 5b, 5b, 5c, 5c). .

According to this configuration, after the core sheet 2 is sent to the heating furnace 1 to melt the surface, the topsheet 4 is overlapped on the core sheet 2 sent out from the heating furnace 1, and the thermocompression roller (
5 a, 5 a, 5 b, 5 b, 5 c, 5 c), and the two sheets 2, 4 that are sent are thermocompression bonded between the thermocompression rollers (5 a, 5 a, 5 b, 5 b, 5 c, 5 c). Therefore, a fiber-reinforced thermoplastic sheet obtained by simply and uniformly laminating the core sheet 2 with the surface sheet 4 can be formed.

Furthermore, in the method for manufacturing a thermoplastic sheet according to the embodiment of the present invention, a plurality of sets of the one-to-one set of thermocompression-bonding rollers (5a, 5a, 5b, 5b, 5c, 5c) are arranged in the feeding direction of both sheets. And the plurality of sets of thermocompression-bonding rollers (5a, 5a, 5b, 5b, 5c,
In 5c), the heating temperature is set to be sequentially lower as it goes in the feeding direction of the both sheets 2 and 4.

According to this configuration, the plurality of sets of thermocompression-bonding rollers (5a, 5a, 5b, 5b, 5c, 5
Both sheets 2 and 4 can be gradually cooled by c). As a result, the top sheet 4 is cooled so as not to be distorted, and the core sheet 2 can be uniformly and reliably laminated with the top sheet 4.

Although one embodiment according to the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to the above-described embodiment. Design changes and the like within the scope not departing from the gist of the present invention are included in the present invention.

It is explanatory drawing of the manufacturing apparatus of the fiber reinforced thermoplastic sheet which concerns on this invention. It is explanatory drawing which shows the example of the heating temperature of a manufacturing apparatus of FIG. 1, and a result.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Heating furnace 2 ... Core sheet 4 ... Top sheet 5 ... Heat press roller group (heating pinch roll group)
5a, 5a ... Heat press roller 5b, 5b ... Heat press roller 5c, 5c ... Heat press roller

Claims (3)

A fiber reinforced thermoplastic sheet comprising a core sheet formed from a mixed fiber of reinforced fibers and thermoplastic resin fibers, and a surface sheet with a small basis weight, and formed by thermocompression bonding the surface sheet to the surface of the core sheet. There,
A fiber-reinforced thermoplastic sheet, which is integrally formed by thermocompression-bonding and cooling the topsheet to the core sheet whose surface has been melted. In a state where a surface sheet with a small basis weight is overlapped on the surface of a core sheet formed from a mixed fiber of reinforcing fibers and thermoplastic resin fibers, heat pressing is performed between a pair of heat pressing rollers while feeding both the sheets. A method for producing a fiber-reinforced thermoplastic sheet, comprising:
After the core sheet is sent to a heating furnace to melt the surface, the top sheet is overlapped on the core sheet sent from the heating furnace and sent between the thermocompression-bonding rollers, and both the sent sheets are heated. A method for producing a fiber-reinforced thermoplastic sheet, characterized by heat-pressing between pressure-bonding rollers. The one-to-one set of thermocompression-bonding rollers is arranged in plural sets in the feeding direction of both sheets,
The method for producing a fiber-reinforced thermoplastic sheet according to claim 2, wherein the heating temperature of the plurality of sets of thermocompression-bonding rollers is set to be sequentially lower toward the feeding direction of the both sheets.

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