JP6863581B2 - Method for manufacturing long fiber reinforced thermoplastic resin linear material - Google Patents

Description

The present invention relates to a method for producing a long fiber reinforced thermoplastic resin linear product composed of a long fiber bundle and a thermoplastic resin matrix.

A fiber-reinforced thermosetting resin article (hereinafter, may be referred to as "FRP") in which reinforcing fibers are bound with a synthetic resin is a material that can replace metal articles because of its high strength and light weight. , Automotive, electronics, agriculture and forestry, building materials, furniture, etc. Pipes, rods, linear objects, etc., which use long fiber bundles such as glass roving, which is one of the products using this FRP technology, as reinforcing fibers and thermosetting resin as a matrix, have been used in various industrial fields for a long time. There is.
In recent years, there has been an increasing demand for using such a long material made of long fiber reinforced resin as an individual member in a product. In order to be able to be used as such individual members, it is necessary that the long material can be shaped to fit the shape of the product at the time of processing the product in which it is used. In particular, it is required that the desired shape can be formed and the shape can be stabilized by temperature stimulation by heating.
However, in general, FRP is completely impregnated with a thermosetting resin as a matrix resin up to the inside of the reinforcing fiber, and after curing, due to the characteristics of the thermosetting resin cured product, it is deformed by heating to obtain a desired shape. It is difficult to plastically process. In particular, an FRP linear material in which fibers are uniformly dispersed in a cross section in the longitudinal direction has extremely high rigidity, is restored to a straight shape even when bent, and does not undergo plastic deformation, so it is suitable for use in bending. Absent.

On the other hand, a fiber-reinforced thermoplastic resin article (hereinafter, may be referred to as "FRTP") in which a reinforcing fiber is impregnated with a thermoplastic resin can be plastically deformed by heating to some extent. However, in the FRTP linear product in which long fibrous reinforcing fibers are impregnated with a thermoplastic resin as a matrix resin, bending processing by heat shaping is not always easy.

Patent Document 1 describes in a method for producing a long fiber reinforced composite material in which continuous reinforcing fibers are drawn and impregnated with a molten thermoplastic resin. After impregnating or coating the fibers with the molten resin, an excessive amount of resin is used with a slit nozzle. Disclosed is a method for producing a long fiber reinforced composite material, which is characterized in that the resin is continuously drawn out while being narrowed down and then adjusted to a desired shape through a shaping nozzle. According to the production method of Patent Document 1, the dispersion of fibers in the obtained composite material and the impregnation property of the resin are also good, and there is an effect that a high-quality composite material can be efficiently and stably obtained. ing.

Further, Patent Document 2 describes a rope made of a carbon fiber reinforced composite material obtained by twisting a plurality of carbon fiber reinforced composite materials having a diameter of 1 to 5 mm in which a long fibrous carbon fiber bundle is impregnated with a thermoplastic resin and a production thereof. The method is disclosed. In Patent Document 2, since the melt viscosity of the thermoplastic resin is generally high, it is difficult to uniformly impregnate the resin in the carbon fiber bundle. However, the thermoplastic resin is discharged at a constant rate by an extruder and impregnated with the resin. Disclosed is a technique of impregnating a carbon fiber bundle with a resin under pressure while opening the carbon fiber bundle, shaping the fiber bundle into a circular shape with a die installed separately from the extruder, and winding it with a winding device.

All of the methods for producing FRTP described in Patent Documents 1 and 2 above have a problem of uniformly impregnating a long fibrous reinforcing fiber bundle with a molten thermoplastic resin, and particularly obtain the obtained FRTP in a longitudinal direction. There is no disclosure of thermoplasticity when bent in the direction.

Further, Patent Document 3 describes a vehicle seat pad including a foam and a resin wire that is insert-molded into the foam to lock a locking portion of the seat skin material, and the resin wire is a plurality. Disclosed is a resin wire having a diameter of 1 to 5 mm, which is obtained by impregnating the long fibers of the above with a thermoplastic resin and impregnating the long fibers having the lightened portion where the resin is lightened at the bent portion with the thermoplastic resin. Has been done. This resin wire imparts thermal bending shapeability by thinning the surface thermoplastic resin intermittently in the cross-sectional direction at a plurality of places where the seat pad is to be molded in advance, and by lightening. The fibers inside the resin wire are exposed to cause the exposed fibers to bond with the foam. However, since the exposed portion of the fibers is limited to the bent portion, the entire resin wire and the foam are bonded. The sex itself was inadequate.

The present inventors have previously made a long-fiber reinforced thermoplastic resin linear product composed of a long-fiber reinforcing material and a thermoplastic resin matrix, which is easily bent in the longitudinal direction by thermal shaping and is easy to handle. A linear product made of a long fiber reinforced thermoplastic resin and a method for producing the same have been diligently studied, and an application has been filed as Japanese Patent Application No. 2016-148732.
The invention according to this application is a long fiber reinforced fabric having a cross-sectional sea-island structure composed of a sea portion made of a matrix resin which is a thermoplastic resin and an island portion consisting of 3 or more and 50 or less island portions made of a long fibrous reinforcing fiber bundle. In the thermoplastic resin linear product, the reinforcing fiber bundle constituting the island portion has a long fiber reinforced thermoplastic having an unimpregnated portion not impregnated with the matrix resin in a cross section orthogonal to the longitudinal direction. It relates to a resin wire.

Further, the applicants have previously made a long fiber reinforced thermoplastic resin linear product suitable for a vehicle seat for a vehicle seat composed of a matrix resin which is a thermoplastic resin and a long fiber reinforced fiber bundle. The long fiber reinforced thermoplastic resin linear product, the reinforcing fiber bundle has an unimpregnated portion not impregnated with the matrix resin in a cross section orthogonal to the longitudinal direction, and is a part of the reinforcing fiber bundle. A long-fiber reinforced thermoplastic resin linear product for vehicle seats, in which the fibers of the above are exposed on the surface of the linear product at 6 to 12 different positions and are continuous in the longitudinal direction of the linear product. A joint application was filed as Japanese Patent Application No. 2016-201598.

Japanese Unexamined Patent Publication No. 5-147116 Japanese Unexamined Patent Publication No. 5-33278 Japanese Unexamined Patent Publication No. 2015-97596

As a result of investigating the thermal shapeability of the long fiber reinforced thermoplastic resin linear material, the present inventors have found that in the linear material having a sea-island structure cross section in the longitudinal direction, a matrix is formed over the entire long fiber reinforced thermoplastic resin fibers. It was confirmed that the structure having an unimpregnated portion without being highly impregnated with a thermoplastic resin as a resin facilitates thermal shaping and improves shaping processability. Since the workability depends on the degree of impregnation of the matrix resin between the single fibers of the long fibrous reinforcing fiber bundle, there may be variations between production lots, which causes problems in quality stability and continuous productivity. It was.
Further, in the production of a long fiber reinforced thermoplastic resin linear product in which a part of a reinforcing fiber bundle is exposed on the surface of the linear material and the bondability with a foam such as polyurethane can be strengthened by the exposed fibers. It is necessary to keep the degree of exposure of the reinforcing fiber bundle on the surface and the degree of bonding between the reinforcing fiber bundle and the matrix resin constituting the linear product within a certain range, and the degree of bonding varies between production lots. There has been a demand for a method of reducing and stably producing.
INDUSTRIAL APPLICABILITY The present invention relates to a method for producing a long fiber reinforced thermoplastic resin linear product composed of a matrix resin which is a thermoplastic resin and a fiber bundle for reinforcing long fibers. To provide a method capable of making the degree of impregnation of a resin uniform, making the physical properties (characteristics) of the obtained long fiber reinforced thermoplastic resin linear product uniform, and continuously and stably producing a long product. The purpose.

The present inventors have developed a long fiber reinforcing fiber bundle having a predetermined number of twists in a method for producing a long fiber reinforced thermoplastic resin linear product composed of a matrix resin which is a thermoplastic resin and a long fiber reinforcing fiber bundle. Is applied to the reinforcing fiber bundle at a predetermined speed with a tension of 5 to 100 g per fiber via the tension adjusting means, the temperature of the preheating device is raised to heat the reinforcing fiber bundle, and the cloth is clothed. Guided to the head die, the molten resin impregnated (contact) part of the guide core and the separated reinforcing fiber bundles and the molten thermoplastic resin are brought into contact with each other in the die, and the thermoplastic resin is applied to each reinforcing fiber bundle. The preheating includes a step of partially impregnating, subsequently passing through a convergence guide, and extruding and coating the long fiber reinforcing fiber bundle group as a linear material under pressure with a die equipped with an extrusion nozzle having a predetermined cross-sectional shape. The heating of the reinforcing fiber bundle in the apparatus achieves the above object by setting the surface temperature of the reinforcing fiber bundle to reach Tm to Tm-200 ° C. with respect to the temperature Tm of the molten thermoplastic resin. Knowing what he could do, he completed the invention of the present application.

That is, the present invention provides the following [1] to [8].
[1] A method for producing a long fiber reinforced thermoplastic resin linear product composed of a matrix resin which is a thermoplastic resin and a fiber bundle for reinforcing long fibers.
(1) A fiber bundle for reinforcing long fibers having a predetermined number of twists is pulled out from a required number of reels via a tension adjusting means, passed through a preheating device that has not been heated, and provided with a separation guide, a molten resin impregnated portion, and a convergence guide. Each fiber bundle is sequentially arranged and inserted into the separation guide of the guide core and the predetermined through holes of the convergence guide, the guide core is attached to the crosshead die main body, and then a sheath core and an extrusion nozzle are provided. Preliminary drawing process of long fiber reinforcing fiber bundle group leading to die, cooling tank, and picking device,
(2) While driving the take-up device and taking up the long fiber reinforcing fiber bundle group at a predetermined speed, a tension of 5 to 100 g per one is applied to the reinforcing fiber bundle via the tension adjusting means. Then, the preheating device is heated to heat the reinforcing fiber bundle, the melt extruder is driven, the thermoplastic resin is supplied to the cross head die, and the guide core metal is impregnated with the molten resin. Each of the separated reinforcing fiber bundles and the molten thermoplastic resin are brought into contact with each other in the portion and the die, and each reinforcing fiber bundle is partially impregnated with the thermoplastic resin, followed by a convergence guide, and a predetermined cross-sectional shape. A step of extruding and coating the long fiber reinforcing fiber bundle group as a linear material under pressure with a die equipped with an extrusion nozzle of the above.
(3) A process of cooling and solidifying an extrusion-coated linear material and taking it back.
Have,
In the step of extruding and coating the linear material, the heating of the reinforcing fiber bundle in the preheating device causes the surface temperature of the reinforcing fiber bundle to be Tm to Tm-200 with respect to the temperature Tm of the molten thermoplastic resin. A method for producing a long fiber reinforced thermoplastic resin linear product, which comprises a range of reaching ℃.
[2] In the (2) extrusion coating step, the ejection hole portion of the extrusion nozzle 23 has a land L of 2 mm or more, and when the hole diameter is A, the extrusion nozzle is a cone having an upper bottom A toward the ejection side. It is hollowed out in a trapezoidal shape, and the angle θ at which the cone base inclined line 232 and the discharge hole wall surface line 231 intersect in the thickness direction cross section of the extrusion nozzle exceeds 90 °, and the opening at the tip of the sheath core facing each other exceeds 90 °. The long fiber reinforcing heat according to the above [1], wherein the molten thermoplastic resin is extruded and coated by a die having a sheath core having a pore diameter B that is 105 to 360% larger than that of the discharge portion pore diameter A. A method for producing a thermoplastic resin linear product.
[3] The long fiber reinforced thermoplastic resin according to the above [1] or [2], wherein the convergence guide of the guide core metal satisfies the following requirements (a) or two requirements (a) and (b). Method for manufacturing linear products.
(A) The hole diameter Dc of the central through hole of the convergence guide is 50 to 100% with respect to the outer diameter Dp of the long fiber reinforced thermoplastic resin linear material.
(B) Twice the radius of the fan-shaped lower side that forms the radial fan-shaped through hole of the convergence guide is defined as the fan-shaped lower side diameter Dfc, and the fan-shaped lower side diameter Dfc is 105 to 105 with respect to the outer diameter Dp of the long fiber reinforced thermoplastic resin wire. The method for producing a long fiber reinforced thermoplastic resin linear product according to the above [1] or [2], which is 360%.
[4] The long fiber reinforced thermoplastic resin linear product according to any one of [1] to [3] above, wherein the required number of the reinforcing fiber bundles are exposed on the surface of the linear product. Production method.
[5] The reinforcing fiber bundle is a multifilament in which fibers having a single fiber fineness of 1.5 dtex to 30 dtex are focused by 80 f to 150 f and have a twist of 2 to 500 times / m. The method for producing a long fiber reinforced thermoplastic resin linear product according to any one of [4].
[6] The reinforcing fiber constituting the reinforcing fiber bundle is made of a thermoplastic resin, and the matrix resin is a thermoplastic resin having a melting point of 20 ° C. or more lower than the melting point or softening point of the reinforcing fiber. The method for producing a long fiber reinforced thermoplastic resin linear product according to any one of [1] to [5].
[7] The reinforcing fiber made of the thermoplastic resin is one or more selected from polyethylene terephthalate fiber, polybutylene terephthalate fiber, polyethylene naphthalate fiber, polytrimethylene terephthalate fiber, polyacrylonitrile fiber, and aliphatic polyamide fiber. The method for producing a long fiber reinforced thermoplastic resin linear product according to the above [6], which is a combined or mixed fiber.
[8] Any of the above [1] to [7], wherein the thermoplastic resin constituting the matrix resin is made of a polypropylene resin having a melt flow rate (230 ° C., 21.18N) of 20 to 100 g / 10 minutes. The method for producing a long fiber reinforced thermoplastic resin linear product according to 1.

According to the method for producing a long fiber reinforced thermoplastic resin linear product of the present invention, the degree of impregnation of the matrix resin, which is a thermoplastic resin, into the fiber bundle for reinforcing long fibers and / or the degree of exposure of the required surface exposed fiber bundle can be determined. It is possible to provide a method capable of stably and continuously producing a long fiber reinforced thermoplastic resin linear product having uniform physical properties (characteristics) with good reproducibility.

It is explanatory drawing of the manufacturing process of the long fiber reinforced thermoplastic resin linear article of this invention. It is a schematic view of the loading type tensor as an example of a thread tension adjusting means, (A) front view, (B) top view. It is a schematic view of the ironing type guide bartender as an example of a thread tension adjusting means, (A) a front perspective view, and (B) a top view. It is a schematic diagram of the tension measuring instrument of a fiber bundle for reinforcement. It is explanatory drawing of the guides of the fiber bundle for strengthening a long fiber which constitutes the guide core metal to be attached to a cross head die, and (B) the cross section which does not have a surface exposed fiber bundle by passing only through the central through hole of a convergence guide. It is an XX line fracture sectional view of (A) separation guide, (B) convergence guide, and (C) convergence guide suitable for manufacturing a sea-island type long fiber reinforced thermoplastic resin linear article. It is explanatory drawing of the guides of the fiber bundle for strengthening a long fiber which constitutes the guide core metal to be attached to a cross head die, and (B) the required number of exposed fibers on the surface by passing through the radial fan-shaped through hole of a convergence guide. It is an XX line fracture sectional view of (A) separation guide, (B) convergence guide, (C) convergence guide suitable for manufacturing a long fiber reinforced thermoplastic resin linear article having a bundle. It is explanatory drawing of the guide core metal which holds the separation guide and the convergence guide of the reinforcing fiber (bundle) used in this invention, (A) the sectional view of one half of the half-split guide core metal, (B) is (B). A is an arrow view, (C) is a front view of one half of the half-split guide core, and (D) is a side view of (C). A description showing the configuration of a crosshead die of a melt extruder used in the present invention and showing the relationship between the hole diameter A of the discharge hole portion of the extrusion nozzle, the land length L, the angle θ, the hole diameter B of the opening at the tip of the sheath core, and the like. It is a figure. It is explanatory drawing which shows the structure of the die used for manufacturing the long fiber reinforced thermoplastic resin linear thing which has the required number of exposed fiber bundles on the surface of Example 2, and (A) is for long fiber reinforced Explanatory drawing schematically showing the state of top view before mounting the guide core metal through which the fiber (bundle) is inserted on the die, (B) explanatory view schematically showing the state of mounting the guide core metal on the die, ( C) It is explanatory drawing which shows typically the state of the fiber bundle for reinforcement in a die, and the flow of a matrix resin. It is explanatory drawing which shows typically the cross section of the long fiber reinforced thermoplastic resin linear article obtained by (A) Example 1 and (B) Example 2 of this invention, and (C) is the line in (B). It is explanatory drawing of the degree of fiber exposure on the surface of a thing.

Hereinafter, a method for producing a long fiber reinforced thermoplastic resin linear product of the present invention will be described with reference to the drawings. In the present invention, the drawings are for explaining the technical idea of the present invention, and are limited to those in which the dimensional balance between each component and the members, the components, and the like are represented in the drawings. There is nothing.

Regarding the method for producing a long fiber reinforced thermoplastic resin linear product of the present invention, first, the preliminary drawing step (1) will be described.
First, as shown substantially in FIG. 1, a long fiber reinforcing fiber bundle F having a predetermined number of twists is pulled out from the required number of reels 1, and the reinforcing fiber bundle is not ascended via the tension adjusting means TC. A cooling water tank 3 that is not filled with cooling water is drawn out from the guide core metal, the sheath core, and the hole of the extrusion nozzle that are passed through the hot preheating device PH and further mounted on the melt extruder E. After that, the work of the preliminary drawing step (1) is performed so that the caterpillar type or the like can be sandwiched between the caterpillars and picked up.
The reinforcing fiber bundle may be passed through the guide core metal 20 by the following procedure.
Reinforcing fiber bundles in predetermined holes of the separation guides 201a and 201b and the convergence guides 202a and 202b shown in FIGS. 5 or 6 attached to the guide core metal 20 shown as a partial cross-sectional view in FIGS. 7A and 7B. Through F, set in the holding grooves 204 and 205 of the respective guides of the half-split guide core metal 20, and combine with the half-split guide core metal of the holding companion to form the cylindrical guide core metal 20. assemble. Next, as illustrated in FIG. 9B for the case of producing a linear product having a required number of exposed fiber bundles on the surface (Embodiment 2), the reinforcing fiber bundle F is passed through a predetermined hole. The guide core metal 20 is fixed to the sheath core 21 fitted in the crosshead die portion 22 of the melt extruder, the reinforcing fiber bundle group is pulled out from the tip of the hole of the extrusion nozzle 23, and the reinforcing fiber bundle group is pulled out and strengthened to the take-up device 4 as described above. Leads a group of fiber bundles.

Next, in the manufacturing method of the present invention, in the extrusion coating step (2), the take-up device 4 is driven to take up the long fiber reinforcing fiber bundle group at a predetermined speed, and the tension adjusting means is applied to the reinforcing fiber bundle F. A predetermined tension is applied to each one through the TC, the temperature of the preheating device PH is raised to heat the reinforcing fiber bundle, and the melt extruder E is driven to supply the thermoplastic resin to the crosshead die 2. As illustrated in FIG. 9C, the separated reinforcing fiber bundles F and the molten thermoplastic resin are brought into contact with each of the reinforcing fibers in the molten resin impregnated portion 203 of the guide core metal 20 and in the die. The bundle is partially impregnated with a thermoplastic resin, and subsequently, through a convergence guide 202a or 202b, a fiber bundle group for reinforcing long fibers is linearly formed under pressure by a crosshead die 2 provided with an extrusion nozzle 23 having a predetermined cross-sectional shape. This is a process of extrusion coating as a product.
After the extrusion-coating step of (2), the long-fiber reinforced thermoplastic resin linear product is produced through the steps of (3) cooling and solidifying the extrusion-coated linear material and taking it back.
Further, in the method for producing a long fiber reinforced thermoplastic resin linear product of the present invention, in the step of extruding and coating the linear product, heating of the reinforcing fiber bundle in the preheating device is performed on the molten thermoplastic resin. It is characterized in that the surface temperature of the reinforcing fiber bundle reaches Tm to Tm-200 ° C. with respect to the temperature Tm.
Hereinafter, the method for producing a long fiber reinforced thermoplastic resin linear product of the present invention will be described in more detail.

<Number of twists and fiber composition of fiber bundles for reinforcing long fibers>
The long fiber reinforcing fiber bundle used in the present invention needs to have a predetermined number of twists. This is because when the required number of reinforcing bundles is exposed on the surface of a linear object, if there is no twist, the part of the fiber bundle in which the single fiber yarn is not adhered to the surrounding matrix resin will fall off. To do. That is, there is a twist, that is, the fiber bundle is twisted at a predetermined spiral pitch in the longitudinal direction, so that the bottom portion, the peripheral wall portion, or the like of the groove portion of the matrix resin at a predetermined position to be exposed is used. At this site, there is a high probability that the twisted single fiber will bite into the matrix resin side and so-called anchor adhesion will occur. That is, the structure is such that the single yarn of the fiber does not fall off by repeatedly appearing on the outermost surface and biting into the matrix resin side. The number of twists of the reinforcing fiber bundle is preferably 2 to 500 times per meter, and if there is a stronger twist than this, the matrix resin will not be well-adapted or embedded near the surface of the fiber bundle, and the surface will be poorly twisted. The reinforcing fiber bundles exposed to the surface are likely to fall off, and the function as a linear object is also reduced. It is possible to use a reinforcing fiber bundle that has no twist at all, but in this case, it is sufficient to twist and feed the yarn to generate a twist of 2 times / m or more and pull it out. When the linear object is cut into short pieces and used, twisting of the length or less is required. For example, when the linear object is cut into 200 mm and used, twisting is performed once within 200 mm, preferably three times or more. I need it. In the commercially available reinforcing fiber bundle used for the reinforcing fiber, polyethylene terephthalate (PET) fiber is twisted 50 times / m, glass yarn is twisted 40 times / m, and aramid fiber is 0 times / m. It is untwisted.
Further, as the reinforcing fiber bundle, a multifilament in which fibers having a single fiber fineness of 1.5 dtex to 30 dtex are focused by 80 f to 150 f and having a twist of 2 to 500 times / m is used. However, it is preferable from the viewpoint that an appropriate reinforcing effect can be exhibited without causing problems such as fluffing during drawing from the creel and difficulty in adjusting the unimpregnated rate of the matrix resin.

<Tension adjusting means for fiber bundles for strengthening long fibers>
In the above-mentioned step (2) extrusion coating, the tension adjusting device used as a tension adjusting means for making the tension of the reinforcing fiber bundle constant during traveling is capable of applying a constant tension to the reinforcing fiber bundle. If there is, there is no particular limitation. It may be a simple type that does not require much space when pulled out from the reel. For example, as shown in FIG. 2, a fiber bundle is passed so as to be sandwiched between two flat plates D having an axial center J, and the upper part is upper. A device (loading type tensor) that adjusts tension by loading a weight W on the upper surface of a flat plate, and two cylindrical guide GBs are erected on a disk as shown in FIG. A so-called "ironing type guide bar tencer" that can change the tension by changing the contact angle θ with the fiber bundle F can also be easily used. Moreover, you may use these in combination.
In the step of extrusion coating (2), the tension on the reinforcing fiber bundle is 5 to 100 g per fiber bundle, more preferably 5 to 95 g, and particularly preferably 10 to 50 g. If the tension is less than 5 g, slack is generated between the single fibers constituting the reinforcing fiber bundle in the manufacturing process, and the continuous production is hindered by entanglement at the inlet of the guides or, in the worst case, cutting. Further, if it exceeds 100 g, it is difficult for the molten thermoplastic resin to impregnate the reinforcing fiber bundle in the molten resin impregnated portion 203 of the guide core metal or in the die, and the long fiber reinforced thermoplastic resin linear material having a low reinforcing effect by the fibers. In addition, when the purpose is a surface-exposed type linear object, since the fiber bundle is not exposed on the surface of the linear object, there is a problem that the locking force with the foam is not developed in insert molding or the like. Occurs.

<Preheating of fiber bundle for reinforcement>
In the production method of the present invention, in the step of extrusion-coating the linear material of (2), heating of the reinforcing fiber bundle in the preheating device is performed with respect to the temperature Tm of the molten thermoplastic resin. The surface temperature of the bundle needs to be in the range of Tm to Tm-200 ° C. As the preheating device PH used, an electric device is desirable from the viewpoint of ease of temperature control, safety, etc., and in the preliminary drawing process, the guide work of the guide core metal of the reinforcing fiber bundle to the separation guide and the convergence guide A structure that can be opened to the lower half and the upper half is preferable from the viewpoint of separating the fiber bundle for burying the inside of the linear object and the fiber bundle for exposure in the predetermined holes. The heating method may be either hot air, a far-infrared heater, or the like. When the hot air type is used, it is preferable to direct the direction of the hot air in the traveling direction of the reinforcing fiber bundle from the viewpoint that the fiber bundle is less likely to be disturbed.

In the step (2), that is, in the step of extruding and coating the long fiber reinforcing fiber bundle group as a linear object, the heating of the reinforcing fiber bundle in the preheating device is performed with respect to the temperature Tm of the molten thermoplastic resin. By setting the surface temperature of the reinforcing fiber bundle to reach Tm to Tm-200 ° C., the thermoplastic resin is partially applied to each reinforcing fiber bundle at the time of contact between the reinforcing fiber bundle and the thermoplastic resin for the matrix. It is possible to impregnate the obtained long fiber reinforced thermoplastic resin linear product with predetermined characteristics. That is, as described with reference to FIG. 9, the surface temperature of the reinforcing fiber bundle F reaches Tm to Tm-200 ° C. at the time when the reinforcing fiber bundle F travels on the molten resin impregnated portion 203 of the guide core metal 20. Must be a range. For example, if the surface temperature of the reinforcing fiber bundle F is room temperature and the yarn is fed to the guide core metal 20, not only the compatibility with the matrix resin is poor, but also the temperature of the matrix resin around the fiber bundle F is lowered, so that the matrix resin When the melt viscosity becomes high, troubles such as fiber breakage may occur and continuous production may not be possible. Once fiber breakage occurs, it is necessary to completely clean the resin pool in the crosshead 2 and then re-thread the fiber bundle F, resulting in a large loss of raw materials and work man-hours.
If the matrix resin uses a thermoplastic resin having a melting point lower than the melting point or softening point of the reinforcing fiber by 20 ° C. or more, a temperature close to the melting temperature Tm of the matrix resin is applied as the preheating of the reinforcing fiber bundle. That's fine. The appropriate surface temperature (preheating) of the reinforcing fiber bundle varies depending on the reinforcing fiber and the matrix resin used, but the surface temperature of the reinforcing fiber bundle is relative to the temperature Tm of the matrix resin in the resin pool in the crosshead. , Tm + 0 ° C. to Tm-50 ° C. is particularly preferable from the viewpoint of physical properties and continuous stable productivity of the obtained long fiber reinforced thermoplastic resin linear product.

<Relationship between the extrusion nozzle hole diameter in the extrusion coating process and the hole diameter at the tip opening of the sheath core>
In the (2) extrusion coating step of the manufacturing method of the present invention, when the land L of the ejection hole portion A of the extrusion nozzle 23 shown in FIG. 8 is 2 mm or more and the hole diameter is A, the ejection hole portion A is directed toward the ejection side. The upper bottom of the extrusion nozzle is hollowed out in a truncated cone shape, and the angle θ at which the truncated cone inclination line 232 and the discharge hole wall surface line 231 intersect in the thickness direction cross section of the extrusion nozzle 23 exceeds 90 ° and faces each other. The hole diameter B of the opening at the tip of the sheath core is 105 to 360% larger than the hole diameter A of the discharge portion, and is extruded and coated with a molten thermoplastic resin by a crosshead die 2 having a sheath core 21. Will be done.
Explaining with reference to FIG. 8, if the land L of the extrusion nozzle 23 is 2 mm or more, high pressure is applied to the portion of the extrusion nozzle 23, so that it is difficult for a linear object (product) to have voids, and the molten thermoplastic resin is formed. It is preferable because it is easy to flow into the molten resin contact portion 203 of the guide core metal in the die and it is easy to control the outer diameter of the linear object. Further, when the angle θ exceeds 90 °, it is preferable in that the flow direction of the matrix resin in the traveling direction and the reverse traveling direction of the reinforcing fiber F can be controlled.
The hole diameter B of the opening at the tip of the sheath core 21 has a diameter ratio (B / A) of 105 to 360% in relation to the hole diameter A of the extrusion nozzle. When the B / A is 105% or more, the matrix resin easily flows into the molten resin contact portion 203 of the guide core metal in the die, and when it is 360% or less, the amount of the molten thermoplastic resin flowing through the guide core metal is increased. It is preferable in that the amount of the molten thermoplastic resin discharged from the extrusion nozzle can be balanced.

<Convergence guide of guide core metal>
In the long fiber reinforced thermoplastic resin linear product of the present invention, the convergence guide preferably satisfies the following requirements (a) or two requirements (a) and (b).
(A) The hole diameter Dc of the central through hole of the convergence guide is 50 to 100% with respect to the outer diameter Dp of the long fiber reinforced thermoplastic resin linear material.
(B) Twice the radius of the fan-shaped lower side that forms the radial fan-shaped through hole of the convergence guide is defined as the fan-shaped lower side diameter Dfc, and the fan-shaped lower side diameter Dfc is 105 to 105 with respect to the outer diameter Dp of the long fiber reinforced thermoplastic resin wire. It is 360%.
First, the requirement of (a) is that, as shown in (C) of FIGS. 5 and 6, the central through hole 202Ca or 202Cb of the convergence guide of the guide core metal 20 is reinforced so as to be arranged inside the linear object. It is a hole through which the fiber bundles for reinforcement are collectively inserted, and from the viewpoint of arranging the fiber bundle for reinforcement inside the linear object, the outer diameter of the long fiber reinforced thermoplastic resin linear object for which the pore diameter Dc is to be obtained. It is preferably 50 to 100% of Dp, and if it is in this range, the reinforcing fiber bundle converged by the central through holes 202Ca and 202Cb is not exposed on the surface, and the reinforcing effect of the linear object is obtained. Can be expressed.
On the other hand, the requirement (b) is to form radial fan-shaped through holes 208b according to the number of reinforcing fiber bundles to be exposed on the surface of the linear object as shown in FIGS. 6 (B) and 6 (C). , 105 to 360% twice the sector under side radius of the radial fan hole 208b as sector under side diameter Dfc, the outer diameter Dp of the fan-shaped under side diameter Dfc long fiber-reinforced thermoplastic resin linear material Within this range, a predetermined number of reinforcing fiber bundles can be exposed on the outer periphery of the linear object.
Furthermore, fan-shaped under side of the radial fan hole 208b is a concentric curvature with respect to the center of the central hole, the tension or the like loaded on the reinforcing fiber bundle, reinforced each be exposed the required number use fiber bundles, it can be moved to the central portion medium substantially sector under side, substantially equally arranged on the outer periphery of the linear material.

In the manufacturing method of the present invention, each reinforcing fiber bundle F drawn out from the creel 1 guides the reinforcing fiber bundle F to the predetermined central through hole 202C of the convergence guide in the guide core metal 20 ( Before the insertion), the separation guides 201a and 201b shown in FIGS. 5 (A) and 6 (A) are inserted into the predetermined holes. A reinforcing fiber bundle to be exposed is guided (inserted) into the holes arranged on the outermost periphery of the separation guide 201b in FIG. 6 (A).

In the present invention, a required number of reinforcing fiber bundles can be exposed on the surface to form a linear product.
That is, in a long fiber reinforced thermoplastic resin linear product composed of a matrix resin which is a thermoplastic resin and a long fiber reinforced fiber bundle, the reinforcing fiber bundle is impregnated with the matrix resin in a cross section orthogonal to the longitudinal direction. It has an unimpregnated portion that is not impregnated, and some fibers of the reinforcing fiber bundle are exposed on the surface of the linear object, for example, at 6 or more and 12 or less separate positions, and the linear object is exposed. It can be a long fiber reinforced thermoplastic resin linear product that is continuous in the longitudinal direction.
In the cross section of a linear object, the length l of each exposed fiber bundle of the reinforcing fiber bundle exposed on the surface is in the range of 0.3 mm to 0.7 mm. It is preferable when it is made of a resin linear material.
By exposing the required number of reinforcing fiber bundles to the surface of the linear object, for example, when it is used as a member for attaching a skin material such as a chair cushion, the long fibers of the exposed portion of the linear object during insert molding. The single fiber of the reinforcing fiber bundle and the foaming agent can be anchored and adhere to each other to exhibit the function as a chair member.

In particular, in the case of a long fiber reinforced thermoplastic resin linear material for a vehicle seat, the outer peripheral length calculated from the deemed outer diameter of the linear object with respect to the total length of the exposed fibers in the cross section of the linear object. The fiber exposure rate calculated as the ratio of 20 to 60% is more preferable.
Both the number of exposed fibers and the exposure rate of the fibers are appropriately determined according to the physical characteristics of the molded product after insert molding, which are required in the use of the linear product.

(Calculation of the number of fiber exposed points and fiber exposure rate of long fiber reinforced thermoplastic resin linear material)
In the method for producing a long fiber reinforced thermoplastic resin linear product of the present invention, the number of exposed fibers and the fiber exposure rate are determined by the following procedure.
(I) A digital microscope (manufactured by KEYENCE, product name: VHX-5000) that cuts a long fiber reinforced thermoplastic resin linear object to a length of about 1 cm in a direction orthogonal to the longitudinal direction so that the cut surface faces up. ) Is fixed on the table with clay or the like.
(Ii) At a magnification of 30 times, observe the sample with reflected light and count the number of fiber bundles exposed on the surface of the long fiber reinforced thermoplastic resin linear material. (= Number of exposed fibers)
(iii) Using the distance calculation function built into the digital microscope, the lengths of the exposed fiber parts (parts not covered by the matrix resin) on the surface are calculated one by one. (= Fiber exposure length at one location)
(Iv) Obtain the total length of the exposed fiber parts, and calculate the fiber exposure rate from the circumference length of the long fiber reinforced thermoplastic resin linear material obtained from the outer diameter by the following formula.
Fiber exposure rate (%) = [(total length of exposed fiber) / (circumferential length)] x 100
The circumferential length of the long fiber reinforced thermoplastic resin wire is calculated from the deemed outer diameter of the long fiber reinforced thermoplastic resin wire. In the observation of (ii) above, the deemed outer diameter is averaged from the maximum and minimum diameters of the portion of the long fiber reinforced thermoplastic resin linear matrix resin (thermoplastic resin) as the outer surface. , Let this be the outer diameter Da without seeing it.

Hereinafter, the reinforcing fiber bundle used in the method for producing a long fiber reinforced thermoplastic resin linear product of the present invention will be described.
(Strengthening fiber bundle)
The reinforcing fiber (bundle) used for producing the fiber-reinforced thermoplastic resin linear product of the present invention is not particularly limited, but is derived from inorganic fibers having no melting point such as glass fiber and carbon fiber, and various thermoplastic resins. Examples thereof include long fiber (filament) -like reinforcing fibers.
As the reinforcing fiber bundle made of a thermoplastic resin, one or a plurality of kinds selected from polyethylene terephthalate fiber, polybutylene terephthalate fiber, polynaphthylene phthalate fiber, polytremethylene terephthalate fiber, polyacrylonitrile fiber, and aliphatic polyamide fiber may be used in combination. Alternatively, mixed fibers can be advantageously selected.
The melting point (Tfm) of the thermoplastic resin fiber needs to be higher than the melting point (Tmx) of the matrix resin as described above. If it is too low, the fibers may melt inside the extrusion die and break. The melting point difference Tfm-Tmx is preferably about 20 ° C. or higher.

The matrix resin, which is the thermoplastic resin used in the present invention, is not particularly limited, but is selected from the thermoplastic resins having a melting point lower than the melting point or the softening point of the thermoplastic fiber used for the reinforcing fiber bundle. More specifically, polyolefins such as polypropylene, polyethylene and polybutylene, and polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylene naphthalate (PENp) and liquid crystal polyester. Resins, styrene resins such as polystyrene (PS), acrylonitrile-butadiene-styrene ABS), acrylonitrile-acrylic-styrene (AAS), acrylonitrile, ethylene propylene rubber, styrene (AES), urethane resins, polyoxymethylene (POM). , Polyamide (PA), Polycarbonate (PC), Polymethylmethacrylate (PMMA), Polyvinyl chloride (PVC), Polyphenylene sulfide (PPS), Polyphenylene ether (PPE), Modified PPE, Polyimide (PI), Polyamideimide (PAI) , Polyetherimide (PEI), Polysulfone (PSU), Modified PSU, Polyethersulfone (PES), Polyketone (PK), Polyetherketone (PEK), Polyetheretherketone (PEEK), Polyetherketoneketone (PEKK) , Polyarylate (PAR), polyethernitrile (PEN), phenolic resins and phenoxy resins. Further, the thermoplastic resin as the matrix resin may be a copolymer or modified product of the above resin and / or a resin in which two or more kinds are blended.
Among these, from the viewpoint of moldability and light weight, a polyolefin resin having a melting point lower than the melting point or softening point of the reinforcing fiber by 20 ° C. or more is preferable, and for example, a polypropylene resin is particularly preferable.

Further, the matrix resin, which is a thermoplastic resin used in the present invention, has a melt flow rate (MFR) (230 ° C., 21.18 N load) of 20 to 100 g / 10 min from the viewpoint of impregnation property into the reinforcing fiber bundle. It is preferably in the range of.
When the MFR is 20 g / 10 min or more, the reinforcing fiber bundle can be impregnated, the reinforcing fiber bundles are less likely to be bundled together, and the reinforcing effect of the reinforcing fiber bundle is exhibited. Further, when the MFR is 100 g / 10 min or less, the physical properties of the resin are less likely to deteriorate, and the FRTP linear material is not easily broken during bending or the like.
Thermoplastic resins used as matrix resins include inorganic fillers such as talc, flame retardants, conductivity-imparting agents, UV absorbers, antioxidants, heat stabilizers, antistatic agents, colorants, as required. Pigments, dyes and the like may be blended.

<Cross-sectional shape of long fiber reinforced thermoplastic resin linear material, etc.>
The cross-sectional shape of the linear object obtained by the production method of the present invention is not limited to a perfect circle, and may take various shapes such as an ellipse and an uneven shape.
Further, the cross-sectional shape of the fiber bundle in the cross section of the linear object is not limited to a perfect circle, but may be an ellipse, a polygon, or the like.
Further, although the distribution of the reinforcing fiber bundles (islands) in the cross section of the linear object is not always uniform, it is preferable that the distribution is point-symmetrical as much as possible with respect to the center of the cross section of the linear object. If the fiber bundle distribution in the cross section is extremely biased, the bendability changes depending on the bending direction of the linear object, which not only makes it difficult to handle, but may also make it easy to break in a specific direction.
Further, the islands formed by the reinforcing fiber bundles are not always clearly separated by the matrix resin, and the adjacent islands may be partially in contact with each other.
The number of reinforcing fiber bundles (islands) must be 3 or more and 50 or less. If it is less than this, it will be easily broken when bent, and if it is more than this, the heat-forming property will decrease.
The size of the reinforcing fiber bundle (island) is not always uniform, and the maximum island area may be about 5 times the minimum island area. That is, those having different fineness of the reinforcing fiber bundles and those having different types of reinforcing fiber bundles may be used.

Hereinafter, the present invention will be described with reference to Examples, but the present invention is not limited to these Examples.

Example 1
(Preliminary drawer process)
As the reinforcing fiber bundle F, 25 polyethylene terephthalate multifilaments (manufactured by Toray Industries, Ltd., single fiber fineness 11.6 dtex) of 1670 dtex / 144 f are drawn out from the reel 1, passed through a preheating device that has not been heated, and are circular as shown in FIG. Through each hole of the separation guide 201a, which has 25 holes with a diameter of 1 mm in the metal plate of the above, one by one, and then all 25 fibers are passed through the circular metal plate with one hole with a diameter of 2.5 mm. Through the convergence guide 202Ca opened in the center of the piece, the reinforcing fiber bundle is passed through the convergence guide 202a so that the reinforcing fiber bundle does not have a reinforcing fiber bundle exposed on the surface of the linear object and the longitudinal cross section becomes a sea-island-shaped linear object. Placed in.
Next, the separation guide 201a and the convergence guide 202a through the reinforcing fiber bundle F shown in FIG. 7 are fitted into the grooves 204 and 205 of one of the half-split guide cores 20 for attaching to the inside of the crosshead die, and are relative to each other. A cylindrical guide core 20 is formed by superimposing it on the other half-split guide core, and a group of reinforcing fibers passed through the convergence guide 202a is attached to the tip of the die to form a circular extrusion nozzle with a diameter of 3.2 mm. After passing through 23, the guide core metal (guide holder) 20 was attached to the rear of the cross head die main body 2.

(Pull-out tension of reinforcing fiber bundle)
The multi-flament, which is a bundle of reinforcing fibers, was attached to a feeding stand in a state of being wound around a paper tube, and was pulled out via a load type tensor TC1 as a tension adjusting means TC shown in FIG. The tension of each reinforcing fiber bundle was adjusted to 20 g / piece by the tension adjusting means TC1.

(Manufacture of long fiber reinforced thermoplastic resin linear material)
The reinforcing fiber bundle group passed through the extrusion nozzle 23 is passed through the cooling water tank 3, and then the preheating device PH is raised to 200 ° C. while being picked up at a speed of 3 m / min using the belt-type take-up device 4. While starting the melt extruder, melt it at an extrusion temperature of 220 ° C, and then add polypropylene resin (made of prime polymer, MFR: 55g / 10min: 230 ° C, 21.18N) to talc for rigidity adjustment, copper damage inhibitor, and blue color. It was a blend of master batches for attachment, and the actual MFR (34.2 g / 10 min) was supplied to the inside of the die. The discharge hole portion of the extrusion nozzle has a land L of 4 mm, a hole diameter A of 3.2 mm, and a truncated cone shape with an upper base A of 3.2 mm toward the discharge side. In the cross section of the extrusion nozzle 23 in the thickness direction, the angle θ at which the truncated cone inclined line 232 and the line 231 on the wall surface of the discharge hole intersect is 125 °, and the hole diameter B of the opening at the tip of the facing sheath core is 6.4 mm. A crosshead die 2 having a sheath core, which is 200% larger than the hole diameter A of the discharge portion, was used. The molten polypropylene resin enters from the outer periphery of the sheath core 21, reaches the tip of the sheath core 21, and then partly is discharged in the direction of the extrusion nozzle together with the fiber bundle passing through the sheath core, but the rest is temporarily discharged. It flows back from the tip of the core 21 to the opening side of the sheath core, and while staying there, impregnates a part of the reinforcing fiber bundle F that has passed through the guide core metal 20. Finally, the shape is given by the extrusion nozzle 23. This was taken up while being cooled in the cooling water tank 3 to obtain a long fiber reinforced thermoplastic resin linear product (rod) having a diameter of 3.4 mm. A schematic cross-sectional view of the obtained long fiber reinforced thermoplastic resin is shown in FIG. 10 (A). Table 1 shows the physical characteristics of the obtained linear material.

Example 2
(Preliminary drawer process)
As a fiber bundle for strengthening, 25 1100 dtex / 95f polyethylene terephthalate fibers (manufactured by Toray) are placed on a circular metal plate with a diameter of 1 mm 25 through a tensor as a tension adjusting means TC and a preheater PH that has not been heated. Six outer holes arranged at a position of PCD φ18 mm among the holes of the separation guide, one by one through one hole of the separation guide 201b (FIG. 6 (A)) in which the holes were formed. Convergence guide 202b in which six fiber bundles passed through the fiber bundle are formed with one hole having a diameter of 2.0 mm in the center of the circular metal plate shown in FIG. 6 (B) and six radial fan-shaped holes around the hole. The remaining 19 fibers, one through each of the six fan-shaped holes and the 19 holes inside the separation guide, were passed through the central hole 202Cb. When the fibers on the outside of the separation guide were passed through the fan-shaped holes 208b of the convergence guide 202b, the fibers were allowed to pass linearly so that the fibers did not intersect with each other. A convergence guide having a diameter Dfc of the fan-shaped lower side 2021 of the radial fan-shaped hole of 7.0 m was used.
Next, in order to attach the separation guide 201b and the convergence guide 202b to the inside of the same crosshead die 2 as in the first embodiment, the separation guide 201b and the convergence guide 202b are fitted into the grooves 204 and 205 of one of the guide cores 20 in a half-split shape, and the other half is split. A cylindrical guide core 20 is formed by superimposing the guide core on the shape, and the reinforcing fiber bundle group passed through the convergence guide 202b is passed through a circular extrusion nozzle 23 having a diameter of 3.2 mm attached to the tip of the die. Then, the guide core metal 20 was attached to the rear of the cross head die main body 2. At this time, the six outer fiber bundles conducted at the position of PCD φ18 mm among the holes of the separation guide were brought into contact with the inner wall of the discharge hole of the extrusion nozzle 23.
The discharge hole portion of the extrusion nozzle has a land L of 4 mm, a hole diameter of 3.2 mm, and is hollowed out in a truncated cone shape with an upper base of 3.2 mm toward the discharge side. In the cross section in the thickness direction of the die, the angle θ at which the truncated cone inclined line 232 and the discharge hole wall surface line 231 intersect is 125 °, and the hole diameter B of the opening at the tip of the facing sheath core is 6.4 mm. A die having the same sheath core as in Example 1, which is 200% larger than A, was used.

(Molding of long fiber reinforced thermoplastic resin linear product)
After passing through the cooling water tank 3 and taking up the reinforcing fiber bundle group through the extrusion nozzle 23 at a speed of 5 m / min using the belt type picking device 4, each reinforcing fiber bundle F from the reel is taken up. As a tension adjusting means, a reinforcing fiber bundle F is passed through a tensor TC1 in which two disc-shaped ceramic plates are inserted between the central shaft J, and a weight W is placed on the disc to adjust the load and measure the tension. While adjusting the tension to 10 g / piece by the device (Tension meter T-101 manufactured by Yokogawa Electronics Co., Ltd.), it is further divided into upper and lower halves to show a cylindrical shape when assembled, and a hot air generator (Ryster Co., Ltd.) The surface temperature of the reinforcing fiber bundle was set to 200 ° C., which is 20 ° C. lower than the extrusion temperature of 220 ° C., by the preheating device PH equipped with (Ryster Electron, manufactured by Technologies), and the melt extruder E was started. After melting at an extrusion temperature of 220 ° C., polypropylene resin (made of prime polymer, MFR: 55 g / 10 min: 230 ° C., 21.18 N) is shown inside the die (221 to 223) and the guide core as shown in FIG. 9 (C). It was supplied to the molten resin contact portion 203 of 20. The long fiber reinforced thermoplastic resin wire 101 having a diameter of 3.4 mm is obtained by taking the long fiber reinforced thermoplastic resin wire coming out of the extrusion nozzle 23 while cooling it in the cooling water tank 3 filled with cooling water. Obtained. FIG. 10 (B) shows a schematic cross-sectional view of the obtained long fiber reinforced thermoplastic resin linear product 101.

The fiber exposed points of the long fiber reinforced thermoplastic resin linear product obtained in Example 2 were 6 places. The fiber exposure rate was 28%. The pull-out strength was 18.3 N, and higher results were obtained as compared with the long fiber reinforced thermoplastic resin linear material having no or less exposed fibers. These results are summarized in Table 1.

Examples 3 to 7, Comparative Examples 1 to 3
In order to establish mass production technology for long fibers of long fiber reinforced thermoplastic resin, the production rate of long fiber reinforced thermoplastic resin wire with a predetermined number of reinforcing fiber bundles exposed on the surface is 20 m. As / min, stable continuous productivity and appearance of exposed fiber bundles were evaluated.
Examples and Comparative Examples in which the pull-out tension of the reinforcing fiber bundle from the creel was 3 g / piece to 120 g / piece and the preheating temperature of the reinforcing fiber bundle was room temperature (20 ° C.) to 200 ° C. under the manufacturing conditions of Example 2. The stable (continuous) productivity and the degree of fiber exposure were observed and evaluated as follows.
(I) Continuous productivity: The case where the production length of 5000 m is produced at a production speed of 20 m / min for about 4 hours is regarded as the standard continuous production, and is evaluated as follows based on the number of fiber breaks of the reinforcing fiber in the production time. ..
◯: No fiber breakage during 4 hours, Δ: 1 fiber breakage during 4 hours, ×: 2 or more fiber breakages (ii) Fiber exposure: 6 reinforcements on the outer peripheral surface of the linear object as in Example 2. When the fiber bundles for use were arranged in an exposed state, the degree of exposure of the fibers was evaluated.
◯: 1/3 or more of the reinforcing fiber bundle is exposed (good), Δ: 1/3 or less is exposed or unstable, ×: No fiber bundle is exposed.
The results are summarized in Table 2.

From Table 2, in Comparative Example 1 in which the withdrawal tension from the creel is 3 g and the preheating temperature is 200 ° C., the reinforcing fiber bundle is broken three times during the four continuous productivity times, and the exposed state of the fiber is ". It was "△". In Comparative Example 2 where the pull-out tension was 5 g / piece and the preheating temperature was room temperature (20 ° C.), thread breakage occurred four times as in Comparative Example 1, but the degree of fiber exposure was good. When the withdrawal tension was 5 g / piece and the preheating temperatures were 150 ° C. (Example 3) and 200 ° C. (Example 4), in Example 3, one thread breakage was observed during production for 4 hours, but it was exposed. The degree was good in both cases. With a preheating temperature of 200 ° C., withdrawal tensions of 5 g / piece (Example 4), 10 g / piece (Example 5 = Example 2), 50 g / piece (Example 6), 100 g / piece (Example 7), At 120 g / piece (Comparative Example 3), when the withdrawal tension exceeded 50 g / piece, the degree of exposure of the fibers tended to deteriorate, which was “Δ” in Examples 6 and 7. As for the continuous productivity, one thread breakage occurred in Example 7 (“Δ”), and in Comparative Example 3, both the continuous productivity and the degree of fiber exposure were “x”.
It was confirmed that even if the production speed was significantly improved according to Examples 3 to 7, stable continuous production was possible and the degree of exposure of the reinforcing fiber bundle was also good.

In the method for producing a long fiber reinforced thermoplastic resin linear product of the present invention, the degree of impregnation of the matrix resin, which is a thermoplastic resin, into the fiber bundle for reinforcing long fibers and the degree of exposure of the surface exposed fiber bundle are adjusted to be uniform. Since it is possible to provide a method for stably and continuously producing long fiber reinforced thermoplastic resin linear products having various physical properties (characteristics) with good reproducibility and easy shaping processing for bending in the longitudinal direction, conventional metal wires are bent. It can be used as a method for manufacturing non-metal members that can replace the applications used in Japan.
Further, the reinforcing fiber bundle that can be used as a long fiber reinforced thermoplastic resin linear product for a vehicle seat has an unimpregnated portion that is not impregnated with the matrix resin in a cross section orthogonal to the longitudinal direction, and is used for the reinforcement. A part of each fiber bundle is exposed on the surface of a long fiber reinforced thermoplastic resin linear material in a separate bundle shape and becomes continuous in the longitudinal direction, and the matrix resin is not impregnated in the reinforcing fiber bundle. When the seat pad is molded, the part is impregnated with the flexible polyurethane foam resin that is the cushioning material of the seat, so that the long fiber reinforced thermoplastic resin linear material can exhibit the bondability between the foam and the long fiber reinforced thermoplastic resin linear material. It can be used as a manufacturing method for stable and continuous production of products.

1 Creel 2 Melt extruder Cross head Die part 3 Water cooling tank 4 Pick-up device 20 Guide core metal 21 Saya core 22 Cross head die body 23 Extrusion nozzle 231 Discharge hole wall surface line 232 Frustrated cone inclined line 100 Long fiber reinforced thermoplastic resin wire State (first aspect)
101 Long fiber reinforced thermoplastic resin linear material (second aspect: required number of surface exposed type)
201a, b Separation guide 202a, b Convergence guide 202C Convergence guide Central through hole 2021 Fan-shaped lower side 203 Molten resin impregnated part 203S Impregnation start point in molten resin impregnated part 203E Impregnation end point in molten resin impregnated part 204, 205 Guide holding groove 206 Flange 207 Mounting hole 208 Radial fan-shaped lightening part or through hole guide part of convergence guide 209 Resin inflow hole 221 Resin flow path in die 222 Resin flow path in die 223 Resin flow path for impregnated part A Extrusion nozzle hole diameter B Saya core tip opening Pore diameter D Disc E Melt extruder F Long fibrous reinforcing fiber bundle Fo'Exposed reinforcing fiber Fi' Internal strengthening fiber G1, G2 1st and 2nd guides (thread guide)
G3 Assembly Guide GB Guide Bar L Extrusion Nozzle Land L Fiber Exposed Location Length M Matrix Resin S Sea I Island TC Tension Adjusting Means PH Preheater W Weight Rfc Convergence Guide Fan Radius Rc Convergence Guide Central Through-hole Radius Dfc Convergence Guide fan-shaped lower side diameter Dc Convergence guide center through-hole diameter

Claims (8)

It is a method for producing a long fiber reinforced thermoplastic resin linear product composed of a matrix resin which is a thermoplastic resin and a fiber bundle for reinforcing long fibers.
(1) A fiber bundle for reinforcing long fibers having a predetermined number of twists is pulled out from a required number of reels via a tension adjusting means, passed through a preheating device that has not been heated, and provided with a separation guide, a molten resin impregnated portion, and a convergence guide. Each fiber bundle is sequentially arranged and inserted into the separation guide of the guide core and the predetermined through holes of the convergence guide, the guide core is attached to the crosshead die main body, and then a sheath core and an extrusion nozzle are provided. Preliminary drawing process of long fiber reinforcing fiber bundle group leading to die, cooling tank, and picking device,
(2) While driving the take-up device and taking up the long fiber reinforcing fiber bundle group at a predetermined speed, a tension of 5 to 100 g per one is applied to the reinforcing fiber bundle via the tension adjusting means. Then, the preheating device is heated to heat the reinforcing fiber bundle, the melt extruder is driven, the thermoplastic resin is supplied to the cross head die, and the guide core metal is impregnated with the molten resin. Each of the separated reinforcing fiber bundles and the molten thermoplastic resin are brought into contact with each other in the portion and the die, and each reinforcing fiber bundle is partially impregnated with the thermoplastic resin, followed by a convergence guide, and a predetermined cross-sectional shape. A step of extruding and coating the long fiber reinforcing fiber bundle group as a linear material under pressure with a die equipped with an extrusion nozzle of the above.
(3) A process of cooling and solidifying an extrusion-coated linear material and taking it back.
Have,
In the step of extruding and coating the linear material, the heating of the reinforcing fiber bundle in the preheating device causes the surface temperature of the reinforcing fiber bundle to be Tm to Tm-200 with respect to the temperature Tm of the molten thermoplastic resin. A method for producing a long fiber reinforced thermoplastic resin linear product, which comprises a range of reaching ℃. In the (2) extrusion coating step, when the land L of the ejection hole portion of the extrusion nozzle 23 is 2 mm or more and the hole diameter of the ejection hole portion is A, the extrusion nozzle is located on the upper bottom A toward the ejection side. The extruded nozzle 23 is hollowed out in a conical shape, and the angle θ formed by the conical base inclined line 232 and the nozzle discharge hole wall surface line 231 exceeds 90 ° in the thickness direction cross section of the extrusion nozzle 23, and the sheath cores 21 facing each other exceed 90 °. The length according to claim 1, wherein the molten thermoplastic resin is extruded and coated by a die having a sheath core in which the hole diameter B of the opening at the tip is 105 to 360% larger than the hole diameter A of the discharge portion. A method for producing a fiber-reinforced thermoplastic resin linear product. The method for producing a long fiber reinforced thermoplastic resin linear product according to claim 1 or 2, wherein the convergence guide of the guide core metal satisfies the following requirements (a) or two requirements (a) and (b). ..
(A) The hole diameter Dc of the central through hole of the convergence guide is 50 to 100% with respect to the outer diameter Dp of the long fiber reinforced thermoplastic resin linear material.
(B) 105 twice the sector under side radius to form a radial fan hole converging guide as sector lower diameter Dfc, the outer diameter Dp of the fan-shaped lower diameter Dfc long fiber-reinforced thermoplastic resin linear material ~ 360%. The method for producing a long fiber reinforced thermoplastic resin linear product according to any one of claims 1 to 3, wherein a required number of the reinforcing fiber bundles are exposed on the surface of the linear product. Any of claims 1 to 4, wherein the reinforcing fiber bundle is a multifilament in which fibers having a single fiber fineness of 1.5 dtex to 30 dtex are focused by 80 f to 150 f and have a twist of 2 to 500 times / m. The method for producing a long fiber reinforced thermoplastic resin linear product according to item 1. Claims 1 to 1, wherein the reinforcing fibers constituting the reinforcing fiber bundle are made of a thermoplastic resin, and the matrix resin is a thermoplastic resin having a melting point of 20 ° C. or more lower than the melting point or softening point of the reinforcing fibers. 5. The method for producing a long fiber reinforced thermoplastic resin linear product according to any one of 5. The reinforcing fiber made of the thermoplastic resin is a combination or a mixture of one or more selected from polyethylene terephthalate fiber, polybutylene terephthalate fiber, polyethylene naphthalate fiber, polytrimethylene terephthalate fiber, polyacrylonitrile fiber, and aliphatic polyamide fiber. The method for producing a long fiber reinforced thermoplastic resin linear product according to claim 6, which is a fiber. The length according to any one of claims 1 to 7, wherein the thermoplastic resin constituting the matrix resin is made of a polypropylene resin having a melt flow rate (230 ° C., 21.18N) of 20 to 100 g / 10 minutes. A method for producing a fiber-reinforced thermoplastic resin linear product.

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