JP3057537B2 - Method for producing mat composed of filament loop assembly - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a mat comprising a filament loop aggregate, and more particularly to a three-dimensional net-like mat comprising a thermoplastic synthetic resin filament loop aggregate used as a rug such as a door mat or a floor mat. Production method.

[0002]

2. Description of the Related Art Conventionally, in this kind of mat production method,
For example, U.S. Pat.
As described in U.S. Pat. No. 3,516,683 and British Patent No. 1,269,108, a cooling liquid is used as a direct medium when a filament extruded from a die is bent into a loop shape, thereby forming a loop. The filaments to be welded to each other are not sufficiently welded, particularly lacking in tensile strength, and there is a problem in the durability of the product.

[0003]

SUMMARY OF THE INVENTION It is a first object of the present invention to make it easy to form a loop of a filament, to weld the filaments firmly, and to obtain a durable thermoplastic resin including tensile strength. An object of the present invention is to provide a method for producing a mat comprising a filament loop aggregate of a synthetic resin. A second object of the present invention is to provide a simple method for producing a mat comprising a filament loop aggregate made of a thermoplastic synthetic resin.

[0004]

[Means for solving the problem]

In order to achieve this object, a method for producing a mat comprising a filament loop assembly 7 according to the present invention comprises the steps of: (a) forming a plurality of filaments 2 of a thermoplastic synthetic resin in a molten state extruded from a die 1; It descends between the net conveyor 3 and the cooling roll 4 rotating at a speed lower than the descending speed, and the one outer filament 2a is brought into contact with the net conveyor 3 and the other outer filament 2b is brought into contact with the cooling roll 4 to bend in a loop. Then, the contact portion is cooled and hardened, and the inner filament 2c is bent into a loop in conjunction with the bending and cooling and hardening of the outer filaments 2a and 2b due to the contact, thereby forming the filament loop aggregate 7 and the filament. The filament loop assembly 7 is lowered in a substantially vertical direction at a speed lower than the descent speed of 2. Than it is.

[0006]

[Function] Extruded from the die 1 180 degrees Celsius to 2 degrees
The temperature of the filament 2 at 00 degrees is rapidly lowered by touching the atmosphere, and the temperature of the filament 2 is adjusted by heating the filament 2 which is falling by the heating means.
The size of the diameter of the formed filament loop is regulated. That is, when the temperature of the filament 2 is increased, a small-diameter loop is formed. On the other hand, when the temperature of the filament 2 is low, a large-diameter loop is formed. The filament density and porosity of the body 7 can be adjusted.

A plurality of filaments 2 in a molten state extruded from a die 1 fall between a net conveyor 3 rotating at a speed lower than the descending speed of the filaments 2 and a cooling roll 4, and one outer filament 2a is conveyed to the net conveyor. 3 and the other outer filament 2
b is brought into contact with the cooling roll 4. Due to this contact, both outer filaments 2a, 2b are curved to form a loop, and the contact portion is hardened by cooling, and the inner filament is interlocked with the curvature of both outer filaments 2a, 2b and cooling and hardening. 2c curves to form a loop. Except for the contact portion between the net conveyor 3 and the cooling roll 4, the filaments 2 in the molten state easily form loops, are easily welded at the contact points with each other, and the welding at the contact points is strong.

In order to cool and harden the filament 2 which comes into contact with the net conveyor 3 and the cooling roll 4, it is necessary to keep the net conveyor 3 and the cooling roll 4 at a low temperature.
The outer filaments 2a and 2b, which are in contact with the net conveyor 3 and the chill roll 4, respectively, are cooled and hardened at the contact portions, so that the surface 8 of the filament loop assembly 7
And the back surface 12 are stabilized, whereby a three-dimensional filament loop aggregate 7 can be formed.

At the time of forming a loop between the net conveyor 3 and the cooling roll 4, the filament loop is oscillated by the air flow 9,
It imparts irregular curvature to the loop being formed and increases the number of points of contact between the filaments. That is, die 1
When the airflow 9 is applied to the filament 2 that is descending further, the filaments come into contact with each other before the loop is formed and welded, and the desired loop formation is hindered. Therefore, the airflow is applied to the filament loop during the loop formation to shake the filament. Motion, thereby causing the loop to bend irregularly or to increase the contact points between filaments.

The filament loop assembly 7 thus formed is pulled substantially vertically downward by the net conveyor 3 at a speed lower than the speed at which the filament 2 descends, and cools the filament loop assembly 7 being lowered. As a cooling means, a cooling air flow 11 is applied from the surface 8 or a cooling liquid is sprayed to cool the filament loop assembly. However, since the filament loop assembly 7 has a large number of small voids between the loops, cooling is efficient. Can be done.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a side view showing a main part of an apparatus for carrying out the manufacturing method according to the present invention, in which a thermoplastic resin is extruded from a die 1 and a plurality of filaments 2 arranged vertically and horizontally at intervals are continuously formed. Forming these filaments 2
Is vertically lowered between the net conveyor 3 and the cooling roll 4 which are arranged to face each other in the horizontal direction.

The distance from the die 1 to the upper end of the net conveyor 3 and the upper end of the cooling roll 4 is set to 3 cm to 10 cm. Usually, the filament 2 extruded from the die at 180 to 200 degrees Celsius suddenly comes into contact with the atmosphere. In the area where the filament 2 descends, a heating means 6 such as a ceramic far-infrared heater provided with a heat reflection plate 5 on both sides of the filament 2 is arranged. The filament 2 is not cooled.

This heating regulates the filament loop forming conditions by adjusting the temperature of the filament 2 descending. Since a filament having the same diameter forms a smaller loop as the temperature of the filament increases, the filament 2 has a smaller diameter. Is heated to a high temperature of about 180 to 200 degrees Celsius, which is almost the same as the extrusion temperature, and a small-diameter loop (for example,
mm). On the other hand, a large-diameter loop (for example, about 10 mm to 12 mm) can be formed by reducing the degree of heating, and in some cases, a larger-diameter loop can be formed without heating the filament.

A driving roll 30 and a driven roll 31 which rotate in the direction of the arrow are arranged facing each other in the vertical direction (vertical direction), and the driving roll 30 and the cooling roll 4 of the net conveyor 3 face each other in a substantially horizontal direction. The net conveyor 3 rotates in the vertical direction, and the cooling roll 4 rotates in the direction of the arrow at a speed lower than the filament descending speed.

One of the filaments 2 in a molten state falling between the net conveyor 3 and the cooling roll 4 is brought into contact with one of the outer filaments 2a and the other outer filament 2b is placed on the peripheral surface of the cooling roll 4. Contact, this contact causes both outer filaments 2
a and 2b are each bent in a loop shape.

As shown in FIG. 4, the metal wire 16
As shown in FIG. 5, the surface of the net conveyor 3 formed in a net shape has moderate irregularities.
a is easily caught to promote loop formation. Although the temperature of the conveyor net once rises due to the contact of the high-temperature filament, it is cooled mainly by air while orbiting between the driving roll 30 and the driven roll 31, and becomes low when the filament 2 comes into contact again. It is desirable that the surface temperature of the net conveyor 3 be maintained at a low temperature of 50 degrees Celsius or less, thereby cooling and hardening the contact portion of the outer filament 2a that contacts the net conveyor 3.

The structure of the net constituting the net conveyor is not limited to those shown in FIGS. 4 and 5, and various structures can be employed.

The cooling roll 4 is formed in a pipe shape.
Various types of cooling media other than the cooling water 20 can be used, and the type and cooling temperature are selected to adjust the peripheral surface temperature of the cooling roll 4. The internal cooling water 20 may be circulated to enhance the cooling effect. The temperature of the peripheral surface of the cooling roll 4 is desirably maintained at a low temperature of 30 degrees Celsius or less. The outer filament 2b in contact with the cooling roll 4 is curved so as to form a loop, and the contact portion is rapidly cooled and hardened.

The outer diameter of the cooling roll 4 is preferably smaller than the diameter of the driving roll 30 of the net conveyor, and preferably the outer diameter is in the range of 10 mm to 25 mm. When the diameter of the cooling roll 4 is small, the contact area with the filament having the loop formed becomes large, so that rapid cooling and hardening of the filament are promoted.

The inner filaments 2c also bend in the form of loops in conjunction with the curvature of the outer filaments 2a and 2b and the cooling and hardening due to the contact between the net conveyor 3 and the cooling roll 4, thereby causing the filament loop aggregate 7 to be bent. Form.

The rapid cooling of the outer filament 2b due to the contact with the cooling roll 4 causes cooling and hardening of the surface 8 of the filament loop aggregate 7 immediately after formation, and is effective in maintaining the filament loop aggregate 7 in a three-dimensional shape. On the other hand, since the filament 2 itself is at a high temperature except for the contact portion between the net conveyor 3 and the cooling roll 4, it is easy to form a loop, and the welding at the contact point between the filaments 2 is easy and strong.

Further, at the time of forming the loop, the filament 2 at the time of forming the loop is preferably swung by the air flow 9 to bend the filament 2 more irregularly. That is, an air current 9 traversing the filament loop aggregate 7 is formed by a blowing means (not shown) such as a blower, and the air flow oscillates the filament at the time of loop formation when traversing the filament loop aggregate 7. The air flow 9 is formed below the cooling roll 4 and the driving roll 30 of the net conveyor, and it is desirable to flow along the lower peripheral surface of the cooling roll and to flow from the lower peripheral surface to the lower peripheral surface of the driving roll of the net conveyor. 1, see FIG. 2).

When an air stream is directly applied to the descending filaments, the predetermined loop formation is greatly hindered by contact and welding of the filaments immediately before the loop formation.
Is a cooling roll 4 and a driving roll 30 of a net conveyor.
, The air flow does not hit the descending filament 2. In order to completely prevent the air flow from directly hitting the descending filament and to control the direction of the air flow, a partition wall 10 can be provided if necessary.

The filament loop assembly 7 thus formed abuts the back surface on the net conveyor 3 and is moved by the net conveyor 3 and the lower guide roll 32.
The filament 2 is lowered in a substantially vertical direction while being taken up at a speed lower than the descent speed of the filament 2, and the filament loop assembly 7 is cooled during the descent.

The cooling of the descending filament loop assembly 7 is performed by a cooling airflow 11. That is, as the net conveyor 3 moves downward, the net conveyor 3
The cooling air flow 11 is applied to the filament loop assembly 7 descending in a substantially vertical direction to cool the filament loop assembly 7.

The cooling air flow 11 is formed by appropriately adjusting the air volume and the air pressure of a blower (not shown), and is cooled by a cooling device (not shown) particularly at a low temperature, and is also cooled at a normal temperature which is not cooled. (Eg, air). Flowing from the front surface 8 of the descending filament loop assembly to the back surface 12 through the inside thereof, and further from the gap 17 of the net constituting the net conveyor 3 to the outside thereof, the three-dimensional shape of the filament loop assembly 7 is obtained. This is effective in efficiently performing cooling while maintaining the temperature (see FIG. 1).

For cooling, in addition to air cooling, the cooling water 13 can be sprayed on the descending filament loop assembly 7.
3 is strongly sprayed from the nozzle 18 onto the filament loop assembly 7 (see FIG. 2). The means for spraying the cooling water 13 can be variously configured in addition to the above. The cooling water 13 includes not only a cooled low-temperature one but also an uncooled one.

Although the filament loop assembly 7 formed between the net conveyor 3 and the cooling roll 4 has a three-dimensional shape, the filament loop has not been completely cured yet. When the filament loop 19 is lowered in an inclined state (see FIG. 6), there is a possibility that the filament loop 19 (see FIGS. 7 and 8) in an upright state partially falls down and overlaps with each other, causing a "striking phenomenon". The filament loop aggregate that has been smashed immediately leads to a defective product.

As shown in FIGS. 1 and 2, when the filament loop assembly 7 is lowered in the vertical direction, the filament loop assembly 7 is unlikely to cause the settling phenomenon, so that the filament loop assembly 7 is lowered in the vertical direction. It is desirable. The allowable inclination angle C when the filament loop aggregate 7 is lowered from the viewpoint of preventing settling is 9
0 degree (in the vertical state shown in FIGS. 1 and 2) to 7
It is 0 degrees (in the case shown in FIG. 6), the inclination angle C is smaller than 70 degrees, and the settling is more likely to occur as approaching the horizontal direction.

Further, a frictional force effectively acts on the filament loop assembly 7 whose back surface 12 is in contact with the net conveyor 3, thereby preventing the filament loop assembly 7 that is vertically lowered from slipping down. Further, the filament loop assembly 7
By sending a cooling airflow 11 having a large wind pressure to the air, or by strongly blowing a cooling liquid 13, the filament loop assembly 7 is pressed against the net conveyor 3 by this pressure, and the downward displacement can be effectively prevented.

In order to completely prevent the filament loop assembly 7 from sliding down, a pin 15 projecting from the net conveyor 3 is provided, and the filament loop assembly 7 can be engaged with the pin 15 as the net conveyor 3 rotates. (See FIG. 3).

The filament loop assembly 7 that has been cooled and separated from the net conveyor 3 is pulled off by a guide roll (not shown) to form a mat. If necessary, the mat can be further cooled in a cooling tank. In addition, it is a matter of course that a mat can be formed on the filament loop assembly 7 after various steps such as coloring coating are added.

FIGS. 7 and 8 are perspective views of a mat manufactured by the manufacturing method of the present invention. In FIG. 7, the mat back surface 12 is composed of a side-by-side loop formed by the contact of the outer filament 2a with the net conveyor 3, whereby the mat back surface 12 has a large filament density and is flat. Other filament loop 19
Is in an upright state, but the mat surface 8 is composed of a loop formed by lightly contacting the outer filament 2b "on the side" of the cooling roll 4, and this filament loop has a tip on the surface 8 side protruding in a chevron shape. Not.

The structure shown in FIG. 8 is the same as that described above except that the back surface 12 of the mat is formed by a loop lying down and a filament loop 19 in an upright state.
The mat surface 8 is provided on the cooling roll 4 with the outer filament 2b.
And the mat surface 8 is flat with a large filament density.

The following is a specific configuration example. (Structural Example 1) 100 parts of polyvinyl chloride (PVC) (P-1300) Plasticizer DOP 50 parts of octyl phthalate Stabilizer 2 parts of dibutyltin laurate 2 parts of cadmium stearate 0.4 part of barium stearate 0.1 parts of coloring agent

The compound material having the above composition is formed into filaments by an extruder. The distance between the net conveyor and the cooling roll is set to 15 mm, the filament forming hole diameter of the T-die is 0.8 mm, the T-die hole arrangement is a 4 mm vertical 4 mm gap, and the horizontal hole pitch is 5 mm. Distance between T die, net conveyor and cooling roll 10
cm, Die temperature 185 ° C, Die pressure 90 kg / cm ² , Extrusion pressure 190 kg / cm ² , 4 ceramic far-infrared heaters ² KW, diameter of metal wire constituting net conveyor 1 mm, gap between metal wires 3 mm Surface of net conveyor Temperature 35 degrees Celsius Circumferential surface temperature of cooling roll 25 degrees Celsius Cooling of the filament assembly blows a cooling air flow of 5 degrees Celsius.

Under the above conditions, at a forming linear speed of 2 m / min,
A loop with a speed of 40 cm is created. The diameter of the loop of the formed filament loop aggregate is about 7 mm, and the thickness is 13.
5 mm and the filament diameter is 1 mm.

(Structural Example 2) 100 parts of polyvinyl chloride (PVC) (P-1300) Plasticizer 5.5 parts of DIDP diisodecyl phthalate LK-40 0.5 parts of organic cadmium chelate 0.7 parts of cadmium stearate Stearin Barium acid 0.3 part Coloring agent 0.1 part

The compound material having the above composition is formed into filaments by an extruder. The distance between the net conveyor and the cooling roll is also set to 15 mm, the filament forming hole diameter of the T die is set to 0.8 mm, the hole arrangement of the T die is 4 rows vertically, 5 mm gap, and the horizontal hole pitch is 5 mm gap. Distance between T-die, net conveyor and cooling roll
5.5cm T dice temperature 190 ℃, dice pressure 80kg / cm
^2. Extrusion pressure 190 kg / cm ² , Ceramic far-infrared heater 2 KW 2 pieces, diameter of metal wire constituting net conveyor 1 mm, small gap between metal wires 3 mm Net conveyor surface temperature 30 degrees Celsius Cooling roll peripheral surface temperature Celsius Cooling of the 22 degree filament loop assembly blows a cooling air flow of 10 degree Celsius.

Under the above conditions, the forming linear speed is 2.5 m / min.
Thus, a loop at a speed of 50 cm is formed. The diameter of the loop of the formed filament loop aggregate is about 10 mm, the thickness is 14 mm, and the filament diameter is 1.1 mm.

[0041]

[Effect] Since a loop is formed by bending a high-temperature filament in the air, it is easy to form a loop, and welding at a contact point between filaments becomes possible, and the welding is strong. This is an effect that cannot be achieved by the conventional production method in which cooling water is used as a medium, and it is easy to form a three-dimensional net-like mat, and is excellent in durability including tensile drag.

Further, a synergistic effect due to the swing of the filament caused by the air flow is added to the bending of the filament due to the contact between the net conveyor and the cooling roll, so that an irregular loop can be formed.

The rapid cooling and curing of the outer filaments by the cooling roll effectively prevents the filament loop aggregates, especially the filament loops located on the surface, from being set.

In addition, since the loop is formed in the air, the operations of adjusting, adjusting, and manufacturing the molding apparatus and the machine are easy and efficient, and a simple method for manufacturing a three-dimensional net-like mat can be provided.

[Brief description of the drawings]

FIG. 1 is a side view showing a main part of an apparatus for performing a manufacturing method according to the present invention.

FIG. 2 is a side view showing a main part of a configuration of another apparatus for performing the manufacturing method according to the present invention.

FIG. 3 is a side view showing an essential part of the configuration of still another apparatus for performing the manufacturing method according to the present invention.

FIG. 4 is a partial plan view of a net of an apparatus for performing the manufacturing method according to the present invention.

FIG. 5 is a partially enlarged perspective view of a net of an apparatus for performing the manufacturing method according to the present invention.

FIG. 6 is a side view showing an inclined net conveyor in an apparatus for practicing the present invention;

FIG. 7 is a perspective view of a filament loop aggregate manufactured by the manufacturing method of the present invention.

FIG. 8 is a perspective view of another filament loop assembly manufactured by the manufacturing method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Die 2 Filament 2a Outer filament 2b Outer filament 2c Inner filament 3 Net conveyor 4 Cooling roll 5 Heat reflection plate 6 Heating means 7 Filament loop aggregate 8 Surface 9 Air flow 10 Partition wall 11 Cooling air flow 12 Back surface 13 Cooling water 14 Pipe 15 Pin 16 Metal wire 17 Gap 18 Nozzle 19 Filament loop 20 Cooling water 30 Drive roll 31 Follower roll 32 Roll C Allowable tilt angle

Claims (15)

(57) [Claims] A plurality of filaments 2 of a thermoplastic synthetic resin in a molten state extruded from a die 1
Is lowered between the net conveyor 3 and the cooling roll 4 rotating at a speed lower than the descent speed, and one of the outer filaments 2a is brought into contact with the net conveyor 3 and the other outer filament 2b is brought into contact with the cooling roll 4 to be bent in a loop. Then, the contact portion is cooled and hardened, and the inner filament 2c is bent into a loop in conjunction with the bending and cooling hardening of the outer filaments 2a and 2b due to the contact, thereby forming the filament loop aggregate 7 and the filament. 2. A method for manufacturing a mat comprising the filament loop assembly 7, wherein the filament loop assembly 7 is lowered in a substantially vertical direction at a speed lower than the descent speed of 2. 2. The method for producing a mat comprising a filament loop assembly 7 according to claim 1, wherein the filaments 2 at the time of forming the loop are swung by an air current. 3. The filament 2 at the time of loop formation is oscillated by an air flow that crosses a filament loop assembly 7 formed below the cooling roll 4 and the driving roll 30 of the net conveyor 3. Item 3. A method for producing a mat comprising the filament loop aggregate 7 according to Item 2. 4. A plurality of thermoplastic synthetic resin filaments 2 descending between a net conveyor 3 and a cooling roll 4.
The method for manufacturing a mat comprising the filament loop aggregate 7 according to claim 1, wherein the heating is performed by heating means. 5. The method of claim 1, wherein the filament is heated to a temperature of 180 to 200 degrees Celsius.
The method for producing a mat comprising the filament loop assembly 7 according to claim 3, wherein the mat is heated at a high temperature. 6. A mat comprising a filament loop assembly 7 as set forth in claim 1, wherein the distance from the die 1 to the upper end of the net conveyor 3 and the upper end of the cooling roll 4 is set to 3 cm to 10 cm. Method. 7. The cooling roll 4 has a diameter of 10 mm to 30 mm.
The method for producing a mat comprising the filament loop assembly 7 according to claim 1, wherein the thickness is set to mm. 8. The production of a mat comprising the filament loop assembly 7 according to claim 1, wherein the surface temperature of the net conveyor 3 is maintained at 50 degrees Celsius or less by cooling accompanying the rotational movement of the net conveyor 3. Method. 9. The method according to claim 1, wherein the peripheral surface of the cooling roll 4 is maintained at 30 degrees Celsius or less. 10. The method according to claim 1, wherein cooling water is circulated inside the cooling roll 4 formed in a pipe shape. 11. The method according to claim 1, wherein the filament loop assembly 7 descending in a substantially vertical direction is air-cooled. 12. Cooling air is blown to the filament loop assembly 7 which descends in a substantially vertical direction by abutting the back side of the net conveyor 3 with the downward movement of the net conveyor 3, thereby cooling the filament loop assembly 7. A method for producing a mat comprising the filament loop aggregate 7 according to claim 1. 13. As the net conveyor 3 moves downward, cooling water is sprayed on the filament loop assembly 7 which abuts the back surface of the net conveyor 3 and descends substantially vertically, thereby cooling the filament loop assembly 7. The filament loop assembly 7 according to claim 1, wherein
A method for producing a mat comprising: 14. A cooling air and / or a cooling liquid is blown onto the filament loop assembly 7 descending by abutting the back surface of the net conveyor 3 with the downward movement of the net conveyor 3, and the wind pressure and / or the liquid pressure is applied. The filament loop assembly (7) according to claim 1, wherein the filament loop assembly (7) is pressed against the conveyor (3).
A method for producing a mat comprising: 15. The method according to claim 1, wherein the filament loop assembly 7 is lowered at an inclination angle of vertical to 70 degrees.