JP2019015014A - Method for producing commingled yarn, commingled yarn, and method for producing woven fabric or knitted fabric - Google Patents

Abstract

To provide a producing method that can obtain a commingled yarn capable of producing a fiber-reinforced resin molding with an arbitrary shape and excellent strength as well as a woven fabric and a knitted fabric.SOLUTION: There is provided a method for producing a commingled yarn composed of at least a thermoplastic resin fiber and a reinforced fiber. The method for producing a commingled yarn comprises a step of commingling thermoplastic resin fibers and reinforced fibers by a fluid entanglement method using gas in the presence of liquid. The commingled yarn of the invention is also composed of at least a thermoplastic resin fiber and a reinforced fiber and comprises at least two or more organic materials, in which these two or more organic materials adhere to both the reinforced fibers and the thermoplastic resin fibers. In addition, the method for producing a woven fabric or a knitted fabric is a method for producing a woven fabric or a knitted fabric composed of at least thermoplastic resin fibers and reinforced fibers, in which the method is performed under a moisture content of the reinforced fibers in the weaving process or in the knitting process of 0.1 to 5 mass%.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for producing a blended yarn, a blended yarn, and a method for producing a woven fabric or a knitted fabric.

  For structural parts such as various machines and automobiles, pressure vessels, and tubular structures, composite material molded bodies in which a reinforcing material such as glass fiber and carbon fiber is added to a resin material are used. The composite material molded body is required to follow an arbitrary shape in order to achieve both weight reduction and strength.

  As a material constituting the composite material molded body, there are proposed mixed yarns and fabrics made of mixed yarns which are continuously mixed uniformly by fluid mixing of reinforcing fibers and thermoplastic resin fibers (for example, Patent Document 1). In order to increase the impregnation property at the time of molding, the mixing condition of the mixed yarn is mainly studied to increase the degree of mixing (the degree to which the fibers are mixed together) (for example, see Patent Document 2). Further, unlike ordinary organic fibers, the reinforcing fibers tend to cause fluff due to damage, and therefore it is necessary to precisely control the conditions for opening and mixing (for example, see Patent Document 3). It is also known that when processing the reinforcing fiber, if the humidity is high, the fiber is difficult to be bulky, that is, the fiber is difficult to open (for example, see Patent Document 4).

  Thus, in the manufacture of mixed fiber using reinforcing fibers, it has been practiced to remove moisture during mixing from the viewpoint of suppressing damage to the reinforcing fibers and increasing the degree of mixing. In addition, handling in a dry atmosphere has been a common sense from the viewpoint of suppressing the adsorption of moisture that interferes when a blended yarn is heated to obtain a molded body.

JP-A-2-112916 JP-A-3-275729 JP-A-4-222246 JP 59-43141 A

  However, conventionally known blended yarns and fabrics are focused on preventing damage to the reinforcing fibers during blending and improving the blended state in order to improve impregnation during molding. In order to apply to structural materials such as automobile materials, higher strength is required.

  As a result of intensive studies to solve the above-described problems of the prior art, the present inventors have mixed thermoplastic fibers and reinforcing fibers with gas in the presence of a liquid, so that high strength and high interfacial strength of the molded body can be obtained. Was found to have been achieved.

  That is, the method for producing a blended yarn of the present invention is a method for producing a blended yarn composed of at least a thermoplastic resin fiber and a reinforcing fiber, in the presence of a liquid and by a fluid entanglement method using a gas. It includes a process of blending thermoplastic resin fibers and reinforcing fibers.

The reinforcing fiber preferably contains 300% by mass or less of the liquid.
The fluid entanglement method is preferably a fluid perturbation method.
The reinforcing fiber preferably contains 0.1 to 5% by mass of a water-soluble component with respect to the reinforcing fiber.
The hydrophilicity index of the reinforcing fiber is preferably 8 degrees or more.

  As another aspect, the method for producing a blended yarn of the present invention is a method for producing a blended yarn composed of at least a thermoplastic resin fiber and a reinforcing fiber, and is a thermoplastic resin fiber and / or a reinforcing fiber. After the step of treating the liquid with a liquid, a fiber mixing step by a fluid entanglement method using a gas is included.

The liquid preferably contains an organic substance.
When the organic substance is mixed in an amount of 10% by mass with respect to the thermoplastic resin fiber, the change rate of the surface tension of the thermoplastic resin fiber is preferably 30% or less.
It is preferable to mix the liquid collected in the mixing process by the fluid entanglement method with the liquid in the process of treating with the liquid.

  The blended yarn of the present invention is a blended yarn composed of at least a thermoplastic resin fiber and a reinforcing fiber, and includes at least two kinds of organic substances. These two or more kinds of organic substances are composed of the reinforcing fibers and the thermoplastic. It is attached to both resin fibers.

The degree of dispersion of the organic matter on the surfaces of the reinforcing fiber and the thermoplastic resin fiber is preferably 5% or more.
The flexibility of the blended yarn is preferably 20 degrees or more.
The porosity of the mixed yarn is preferably 20% or more.
The total amount of organic matter is preferably less than 2% by mass with respect to the mixed yarn.

  The method for producing a woven fabric or knitted fabric of the present invention is a method for producing a woven fabric or knitted fabric comprising at least a thermoplastic resin and reinforcing fibers, and the liquid content of the reinforcing fibers in the reinforcing fiber weaving step is 0.1-5. It is performed by mass%.

  According to the method for producing a blended yarn, the blended yarn, or the method for producing a woven or knitted fabric of the present invention, the blended yarn or the woven fabric capable of producing a fiber-reinforced resin molded article having an arbitrary shape and excellent strength. You can get a knitted fabric.

It is a schematic diagram for demonstrating a taslan process. It is a schematic diagram which shows the state which wound mixed fiber around the aluminum formwork used in the Example. It is a schematic diagram which shows the metal mold | die used in the Example.

  Hereinafter, the present invention will be described in detail. The present invention is not limited to the following, and can be implemented with various modifications within the scope of the gist.

<Mixed yarn>
The mixed fiber in the present invention refers to a thread composed of at least reinforcing fibers and thermoplastic resin fibers. The reinforcing fibers and / or thermoplastic resin fibers are preferably multifilaments from the viewpoint of yarn strength and handleability. A part of the multifilament single yarn of the reinforcing fiber may be cut, but the reinforcing fiber bundle is preferably continuous from the viewpoint of strength. The thermoplastic resin fibers may be in any form, but continuous fibers are preferred from the viewpoint of the stability of the fiber mixing process.

  The mixed state of both fibers is not particularly limited, the two fibers are aligned, the two fibers are mixed in a single yarn unit, the one fiber covers the periphery of the other fiber, the twisted state Etc. In order to improve the impregnation property during molding and to develop high strength, it is preferable that only a part of both fibers are mixed in a single yarn unit. Since the straightness of the reinforcing fiber increases as the mixing amount decreases, high strength tends to be easily developed. By having the minimum mixing portion, the impregnation can be quickly advanced from there. The mixing ratio of the reinforcing fibers is preferably 0.1 to 20%, more preferably 0.2 to 15%, and still more preferably 0.3 to 10%. The degree of blending is defined by the ratio of the number of reinforcing fibers adjacent to the thermoplastic resin fibers to the total number of reinforcing fiber bundles, and is calculated by observing 20 cross-sections at arbitrary positions of the blended yarn.

  The volume ratio of the reinforcing fiber to the thermoplastic resin fiber in the blended yarn is preferably 50 to 900% by volume, more preferably 66 to 400% by volume from the viewpoint that high strength and a clean appearance can be achieved. More preferably, it is 81-233 volume%.

  The mixed fiber of the present invention contains at least two kinds of organic substances, and these two or more kinds of organic substances are attached to both the reinforcing fiber and the thermoplastic resin fiber. Since both the reinforcing fiber and the thermoplastic resin fiber have two or more kinds of the same kind of organic matter, the affinity between both fibers is increased and the handleability as a yarn is improved, and the effect of improving the impregnation property at the time of molding is obtained. It is done. Since these effects are further enhanced, it is preferable that at least one of the organic substances is water-soluble. In addition, when the total amount of the organic matter is too large, the handleability may be deteriorated. Therefore, the total amount of these organic matter is preferably less than 2% by mass with respect to the mixed yarn. % Or less, more preferably 1.4% by mass or less, and most preferably 1.1% by mass or less.

  The number of types of organic matter to which the mixed fiber is attached can be calculated by liquid chromatography mass spectrometry after extracting from the mixed fiber using an appropriate solvent. The amount of organic matter adhering to the reinforcing fiber and thermoplastic resin fiber in the blended yarn is determined by separating the reinforcing fiber and thermoplastic resin fiber from the blended yarn, extracting each fiber with water, and then extracting with solvent. The amount of water-soluble component and the amount of water-insoluble component can be quantified, respectively. In addition, the NMR measurement of the extract is used for the origin of the component, that is, the component (A) contained in the raw material reinforcing fiber, the component (B) contained in the raw material thermoplastic resin fiber, and the mixed fiber. It can be separated into the component (C) contained in the liquid. It is preferable that each of the reinforcing fiber and the thermoplastic resin fiber contains both components (A) and (B) from the viewpoint of impregnation characteristics and strength development at the time of molding.

  These organic substances are attached with a dispersion degree of 5% or more on the surface of the reinforcing fiber or the thermoplastic resin fiber, which increases the impregnation property at the time of molding and the final interface strength in the molded body. It is preferable from the viewpoint. The degree of dispersion is more preferably 10% or more, and further preferably 15% or more. The degree of dispersion can be calculated as follows. The organic matter is extracted from the blended yarn, the mass is measured, and the ratio of the mass of the organic matter to the mass of the blended yarn is calculated. The measurement is performed in the same manner at any 20 locations to calculate the average value and the standard deviation, and the value obtained by dividing the standard deviation by the average value is defined as the degree of dispersion.

  From the viewpoint of handleability in the case of weaving, knitting, braiding, etc. of the blended yarn, the flexibility of the blended yarn is preferably 20 degrees or more, more preferably 40 degrees or more, and 60 degrees or more. More preferably, it is most preferably 80 degrees or more. The softness of the blended yarn is obtained by cutting the blended yarn by 20 cm and fixing the ends with a tape having a width of 1.5 cm to form a ring. Hold the part fixed with tape and hang it vertically. If it is not vertical at this time, hold it lightly with your hand to make it vertical. While holding the tape part, turn it 180 degrees vertically so that the mixed yarn stands vertically with the tape part underneath. Hold the blended yarn for 1 minute and measure the angle at which the blended yarn hangs down in the vertical direction. In addition, when it bends in two steps, the one with the larger angle is adopted.

  From the standpoint of balancing the handleability of the blended yarn in the process of weaving, knitting, and braiding, and the subsequent handling of the woven, knitted, and braided fabric, the flexibility of the blended yarn depends on moisture absorption. It is preferable that can be changed. The amount of change in the flexibility of the mixed yarn before and after moisture absorption is preferably 30 degrees or more, preferably 40 degrees or more, and more preferably 50 degrees or more.

From the viewpoints of handling properties during weaving, knitting, braiding, etc. of mixed fiber yarns and suppressing damage during handling, the mixed yarn preferably contains voids inside, and the porosity is 20% or more. Preferably, it is 25% or more, more preferably 30% or more. The porosity can be obtained by wrapping the mixed yarn with a shrink tube, injecting a colored epoxy resin into the tube and curing, cutting, polishing, and observing the cross section.
Porosity = Area of the void / area inside the outer periphery of the mixed yarn × 100
The area of the void is the area of the colored epoxy resin inside the outer periphery of the mixed yarn, and the outer periphery of the mixed yarn is a figure drawn by a line connecting the fibers on the outermost side.

  The mixed yarn may contain fibers other than reinforcing fibers, thermoplastic resin fibers, and organic matter. It is preferable to add an antioxidant, an ultraviolet absorber, a colorant, a heat transfer agent, a heat stabilizer and the like depending on the environment in which the molded body is used.

<Method for producing blended yarn>
The blended yarn in the present invention is produced by blending reinforcing fibers and thermoplastic resin fibers with gas in the presence of a liquid. Here, the liquid means a liquid under the temperature and pressure of the processing conditions. The type of liquid may be appropriately selected according to the processing conditions, and water, an organic solvent, or the like can be used as appropriate. Water is particularly preferable from the viewpoint of stability. The gas means that it is gaseous immediately before coming into contact with the reinforcing fiber and / or the thermoplastic resin fiber. The type of gas may be appropriately selected according to the processing conditions, and air, steam, organic gas, or the like can be used as appropriate. Air is preferable from the viewpoint of stability.

  By aggressively adding liquid, it is possible to suppress damage to the reinforcing fibers during fiber mixing, and even in a low mixed state, the resin quickly impregnates the reinforcing fibers during molding, resulting in high tensile strength and interface. Strength develops. The amount of the liquid is not particularly limited, and an optimum amount can be adjusted according to the reinforcing fiber to be used, the kind of the thermoplastic resin, the single yarn diameter, the fineness, and the like. Examples of the liquid addition method include a method of adding as a vapor and a method of adding as a liquid. From the viewpoint of the impregnation property at the time of molding and the strength of the molded body, it is preferably added as a liquid. Either the reinforcing fiber or the thermoplastic resin fiber may be contained, but at least the reinforcing fiber is preferably contained, and more preferably both are contained. Since it is preferable that liquid mixing is performed at the time of fiber mixing, it is preferable to include a step of liquid mixing immediately before fiber mixing. In order to contain both reinforcing fiber and thermoplastic resin fiber, it is not necessary to go through the step of soaking both of them, for example, after going through the step of containing the reinforcing fiber, it is reinforced by aligning with the thermoplastic resin fiber. The fiber liquid may be moved to the thermoplastic resin fibers.

  The liquid preferably contains an organic substance. In the liquid containing step, the liquid may contain a different kind of organic substance from the organic substance contained in the liquid. The organic matter at this time is one that enhances the affinity between the reinforcing fiber and the thermoplastic resin fiber, one that suppresses the generation of static electricity by imparting hydrophilicity, coloring and flame retardancy, heat resistance, weather resistance in the molded product It is preferable to add materials that are difficult to impart to reinforcing fibers and thermoplastic resin fibers, such as those that impart functions such as those that promote the opening of reinforcing fibers during molding and enhance the impregnation action. Considering the remaining efficiency of the organic matter in the blended yarn after the blending step, the organic matter is preferably finely dispersed in the liquid, and more preferably in an emulsion state as an aqueous dispersion.

In order to achieve impregnation and high physical properties by molding in a short time, the organic substance has a rate of change of the surface tension of the thermoplastic resin fiber of 30% or less when the organic substance is mixed with 10 mass% of the thermoplastic resin fiber. Preferably 20% or less, more preferably 15% or less, and most preferably 10% or less.
Further, the difference in surface tension between the organic matter and the thermoplastic fiber is preferably less than 22, more preferably less than 17, further preferably less than 12, and most preferably less than 7. The surface tension is measured at a temperature 45 ° C. higher than the higher temperature among the melting points of the organic substance and the thermoplastic resin fiber.

In order to develop good physical properties after impregnation, the difference in SP value (solubility parameter) between the thermoplastic resin fiber and the organic substance is preferably less than 3 (cal / cm ³ ), more preferably less than 2. Preferably, it is less than 1.5, more preferably less than 1.

  As a preferable organic substance satisfying these, polymers and oligomers similar to thermoplastic resin fibers are particularly preferably used. Here, the same system means that the organic substance has a functional group that the repeating unit of the thermoplastic resin fiber has. For example, when the thermoplastic resin fiber is polyamide 66, an organic substance having an amide bond is preferably applied.

  From the viewpoint of controlling the amount of organic matter added, the step of containing liquid is preferably a method of spraying a liquid containing organic matter and recovering the remaining amount, or a method of immersing in a liquid in a circulating state to control the concentration. Since excess organic matter is recovered together with the excess liquid in the fiber mixing step by gas, it is preferable to recycle the recovered product into a liquid-containing step.

  The liquid content is not particularly limited, and may be appropriately selected in such an amount that the above-mentioned effects can be obtained. From the viewpoint of increasing productivity and suppressing waste liquid, the liquid content of the reinforcing fibers is 300 mass. % Or less, more preferably 250% by mass or less, still more preferably 200% by mass or less, and most preferably 150% by mass or less. The liquid content can be obtained by stopping the line in a state where the process is stable, cutting off the front part of the fiber mixing step and measuring the weight, and then measuring the weight in a state where the liquid is removed.

  The interfacial shear stress of the reinforcing fiber in the mixed yarn is preferably changed with respect to the interfacial shear stress of the raw reinforcing fiber, and more preferably increased by 5% or more with respect to the interfacial shear stress of the raw reinforcing fiber. More preferably, it increases by 10% or more, and most preferably increases by 15% or more. In order to change the interfacial shear stress, it is possible to move components such as a sizing agent adhering to the reinforcing fiber by the liquid. The interfacial shear stress can be measured by the micro droplet method.

  The method for unraveling the reinforcing fibers can be selected as appropriate, and examples thereof include interior removal, exterior removal and rolling. From the viewpoint of suppressing damage in the yarn path, it is preferable that the reinforcing fiber before unwinding is in a liquid-containing state. When the reinforcing fiber is produced, the sizing agent may be applied when the sizing agent is applied, or it may be used after it has been impregnated. As a method of impregnating the liquid, the liquid may be immersed in a predetermined liquid, the liquid may be sprayed by spraying or the like, or the humidity may be maintained for a predetermined time. When it is difficult to use after making it into a liquid-containing state, rolling that can be unwound without twisting the reinforcing fiber is preferable. The liquid content during unwinding is not particularly limited, but the flexibility of the reinforcing fiber immediately after unwinding is preferably 5 degrees or more, more preferably 10 degrees or more, and 15 degrees or more. Further preferred. The softness can be measured in the same manner as the softness of the mixed yarn described above.

  As a method for mixing fibers, a known method can be used according to the structure of the mixed yarn, and several mixing steps may be used in combination. The following describes a method for producing a blended yarn in which reinforcing fibers and thermoplastic resin fibers, which are preferable in the form of blended yarn, are blended, or a blended yarn in which reinforcing fibers and thermoplastic resin fibers are mixed in single yarn units. To do.

  For example, after opening by external force due to electrostatic force, pressure by fluid spraying, pressure applied to rollers, etc., and then opening and closing the reinforcing fiber bundle and the thermoplastic resin fiber, the opening and combining yarn method And fluid entanglement method. A fluid entanglement method that can remove excess liquid by gas while mixing is preferably used. The fluid entanglement method is a method in which fibers are entangled by the action of a fluid, and examples thereof include a fluid disturbance method and an interlace method (air is applied to the yarn in the transverse direction). When carbon fiber that is easily damaged by external force from the side is used as the reinforcing fiber, the fluid disturbance method is preferably used, and the Taslan (registered trademark) method in which air is applied in the same direction as the yarn traveling direction is particularly preferably used. . The thickness and number of reinforcing fiber bundles as raw materials are appropriately adjusted, and the production conditions are adjusted accordingly.

  Hereinafter, taslan processing which is a preferred embodiment of the present invention will be described. Taslan processing is a technique in which the yarn sent from the core yarn and float yarn is bulky by the force of air and is strongly bound in a loop shape. For example, as shown in FIG. 1, when the core yarn and floating yarn sent by the rotation of the roller pass through the nozzle attached in the Taslan box, the filaments are bound by being disturbed by the force of air. The core yarn is the yarn that becomes the core of Taslan yarn, and the floating yarn is entangled closely around it. It is preferable to set the feeding amount of the supply yarn by the roller more on the floating side than on the normal core side. The nozzle is mainly composed of a housing and a core, and air is blown out from a hole called an orifice in the core and bound.

  The core yarn and the float yarn may be either a reinforcing fiber or a thermoplastic resin fiber, but from the viewpoint of strength, it is preferable to use the reinforcing fiber as the core yarn and the thermoplastic resin fiber as the float. From the viewpoint of the strength and productivity of the mixed yarn, the yarn speed is preferably 10 to 1000 m / min, more preferably 20 to 700 m / min, and further preferably 30 to 500 m / min. Most preferably, it is 50-300 m / min.

The feeding of the reinforcing fiber is preferably 0 to 10%, preferably 0.1 to 5% with respect to the yarn speed from the viewpoint of improving the strength of the formed body by increasing the linearity of the yarn. More preferably, it is more preferably 0.2 to 3%, and most preferably 0.3 to 1.8%. The feed of the thermoplastic resin fiber may be arbitrarily adjusted from the viewpoint of adjusting the entanglement with the reinforcing fiber, preferably 1 to 15%, more preferably 2 to 10%, and more preferably 3 to 7%. More preferably, it is 4 to 6%. The float feed amount with respect to the core yarn is preferably 100 to 600%, more preferably 110 to 500%, and most preferably 150 to 400%. Air pressure is suppressed damage reinforcing fibers, with creating a proper confounding conditions, it is preferably 0.5~10kgf / cm ² from the viewpoint of moderately blow the liquid, to be 1~5kgf / cm ² More preferably, it is 1.5-3 kgf / cm < ² >. The liquid content can be controlled by blowing reinforced fibers and / or thermoplastic resin fibers before the taslan box and blowing off the liquid while mixing with air.

<About water-soluble ingredients>
The mixed yarn in the present invention preferably contains a water-soluble component. A water-soluble component refers to a compound that exhibits a solubility of 10 g or more in 100 g of water at 23 ° C. For example, low molecular weight compounds having reactive groups such as water-soluble polymers such as polyvinyl pyrrolidone, polyethylene glycol and derivatives and copolymers thereof, polyacrylic acid, polysulfonic acid, polyvinyl alcohol, polyvinyl acetamide, cellulose derivatives, starch derivatives, etc. An epoxy resin and an acrylate resin are preferably used.

  The water-soluble component only needs to be contained in the reinforcing fiber and / or the thermoplastic resin fiber in the mixed yarn, but if it is contained in both, the adhesion between the two is increased and it becomes easy to impregnate during molding. preferable. Moreover, it is preferable that the surface of the reinforcing fiber is non-uniformly attached because the interface strength between the reinforcing fiber and the thermoplastic resin serving as the matrix tends to increase in the molded body. From the viewpoint of the balance between the impregnation property and the interfacial strength, the water-soluble component is preferably 0.1 to 5% by mass, more preferably 0.3 to 4% by mass with respect to the reinforcing fiber, More preferably, it is -3 mass%, and it is most preferable that it is 1-2 mass%.

  The water-soluble component may be added to the raw material, may be added when blending, or may be added after producing the blended yarn. It is preferable to add to the reinforcing fiber of the raw material from the viewpoint that it tends to adhere nonuniformly to the surface of the reinforcing fiber. When the reinforcing fiber contains a water-soluble component, the water-soluble component moves by the liquid when it comes into contact with the liquid in the fiber mixing step. As a result, the water-soluble component is distributed on the surface of the reinforcing fiber and also moves to the thermoplastic resin fiber.

<About reinforcing fibers>
Reinforcing fibers may be those used for ordinary reinforcing fiber composite material molded products, and are not limited to the following, but include, for example, glass fibers, carbon fibers, aramid fibers, ultra-high strength polyethylene fibers, Preferred examples include at least one selected from the group consisting of polybenzazole fibers, liquid crystal polyester fibers, polyketone fibers, metal fibers, and ceramic fibers. Glass fibers, carbon fibers, and aramid fibers are preferable from the viewpoint of mechanical properties, thermal characteristics, and versatility, and carbon fibers are preferable from the viewpoint of elastic modulus.

  The single yarn diameter of the reinforcing fiber is not particularly limited, but is preferably 1 to 22 μm, more preferably 3 to 17 μm, and further preferably 5 to 12 μm from the viewpoint of the strength and handleability of the molded body. preferable. The number of filaments as the reinforcing fiber bundle can be appropriately set according to the handleability, and those of 3000, 6000, 12000, and 24000 are preferably used.

  It is preferable to use a sizing agent for the reinforcing fiber, a coupling agent for forming the interface between the reinforcing fiber and the thermoplastic resin, and improving the handleability of the reinforcing fiber and assisting the formation of the interface between the thermoplastic resin and the coupling agent. For example, a bundling agent for improving the handling property of the reinforcing fiber and a lubricant for improving the handling property of the reinforcing fiber are preferably used.

  The surface condition of the reinforcing fiber is changed by the sizing agent. It is preferable from the viewpoint of the strength of the mixed fiber and the strength of the molded body that the reinforcing fiber is in a state of high affinity with the liquid used in the fiber mixing step. Here, the state in which the reinforcing fiber is in a state having high affinity with the liquid means a state in which the reinforcing fiber bundle spreads and falls apart when the reinforcing fiber bundle is cut out to about 5 cm and placed in a liquid tank. .

The sizing agent is preferably applied as a liquid or a gas from the viewpoint of uniformly coating the reinforcing fiber. When using a compound having a high melting point and boiling point, it may be applied while heating, or may be applied after being dissolved in a solvent. As other components, an antioxidant, an ultraviolet absorber, a colorant, a heat transfer agent, a heat stabilizer and the like may be contained.
As a method for selecting the type of sizing agent, for example, use of the interfacial strength with the matrix resin by a microdroplet test as described in JP-A-2015-67926 can be mentioned. However, since the sizing agent may be volatilized or denatured by heat, it is preferable to perform the test after applying a heat history during molding. It is preferable to use the water-soluble component mentioned above as a sizing agent.

  The lubricant contributes to the adjustment of the reinforcing fibers, the improvement of damage prevention, and the improvement of the spreadability. As the lubricant, any ordinary liquid or solid lubricating material suitable for the purpose can be used, and is not particularly limited. For example, animal or plant or mineral wax such as carnauba wax or lanolin wax; fatty acid amide One or more selected from surfactants such as fatty acid esters, fatty acid ethers, aromatic esters, and aromatic ethers can be used.

  The binding agent contributes to the improvement of the binding property of the reinforcing fiber and the improvement of the interfacial adhesive strength. As the binder, a polymer or a thermoplastic resin suitable for the purpose can be used. Although it does not restrict | limit especially as a polymer, For example, Epoxy resins, such as a bisphenol A type epoxy resin; Phenol resin obtained by making various phenols and formalin react; Urea resin obtained by making urea and formalin react; Melamine and formalin And thermosetting resins such as melamine resins obtained by reacting with. In addition, for example, polyurethane resins synthesized from isocyanates such as m-xylylene diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate) and isophorone diisocyanate, and polyester or polyether diols are also preferably used. Is done.

  The thermoplastic resin used as the binder is not particularly limited. For example, polyolefin resin, polyamide resin, polyacetal resin, polycarbonate resin, polyester resin, polyether ketone, polyether ether ketone, polyether sulfone. , Polyphenylene sulfide, thermoplastic polyetherimide, thermoplastic fluororesin, and modified thermoplastic resins obtained by modifying these. If the same kind of thermoplastic resin and / or modified thermoplastic resin as the thermoplastic fiber forming the mixed yarn is used, the adhesion between the reinforcing fiber and the thermoplastic resin fiber is improved after the composite material is formed. preferable.

  From the viewpoint of increasing the efficiency of the fiber mixing process, the hydrophilicity index of the reinforcing fiber used in the present invention is preferably 8 degrees or more, more preferably 30 degrees or more, and further preferably 60 degrees or more. The hydrophilicity index here is a unique index for adaptability to the mixed fiber process of the present invention. The hydrophilicity index is measured by the same measurement as the softness of the blended yarn at the time of drying and wetness as shown in the examples, and is expressed by the difference between the two.

<About thermoplastic resin fibers>
As the thermoplastic resin fiber, one obtained by fiberizing a matrix resin usually used for a composite material can be used. For example, polyolefin resins such as polyethylene and polypropylene; polyamide resins such as polyamide 6, polyamide 66 and polyamide 46; polyester resins such as polyethylene terephthalate, polybutylene terephthalate and polytrimethylene terephthalate; polyacetal resins such as polyoxymethylene Polycarbonate resin; polyether ketone; polyether ether ketone; polyether sulfone; polyphenylene sulfide; thermoplastic polyetherimide; thermoplastic fluororesin such as tetrafluoroethylene-ethylene copolymer; It is preferably a continuous fiber obtained by melt spinning at least one kind of thermoplastic resin selected from thermoplastic resins.

Among these thermoplastic resins, polyolefin resins, polyamide resins, polyester resins, polyether ketones, polyether ether ketones, polyether sulfones, polyphenylene sulfides, thermoplastic polyether imides, and thermoplastic fluorine resins are preferable. Polyolefin resins, modified polyolefin resins, polyamide resins and polyester resins are more preferable from the viewpoints of mechanical properties and general versatility, and polyamide resins and polyester resins are more preferable from the viewpoint of thermal properties. In addition, a polyamide-based resin is more preferable from the viewpoint of durability against repeated load application, and an aliphatic polyamide-based resin, particularly polyamide 6 and polyamide 66 can be suitably used.
The thermoplastic resin fiber may contain a lubricant, an antioxidant, an ultraviolet absorber, a colorant, a heat transfer agent, a heat stabilizer, etc., and gives a compound having a high affinity with the liquid at the time of fiber mixing. It is preferable to increase the fiber mixing efficiency and to improve the impregnation property by sharing this compound with the reinforcing fiber.

<About fabric and knitting>
It is preferable to use the blended yarn of the present invention as a cloth and use it as an intermediate material for obtaining a fiber-reinforced resin molded product. Although the form of the cloth is not particularly limited, a unidirectional reinforcing material obtained by aligning mixed yarns in a specific direction, a cloth using a composite thread, such as a woven fabric, a knitted fabric, a lace, a felt, a nonwoven fabric, a film, a plate-like body, and the like Can be mentioned. As the intermediate material, a flexible unidirectional reinforcing material, woven fabric, knitted fabric, lace, felt, and non-woven fabric is preferable from the viewpoint of shape followability in the mold when manufacturing a fiber-reinforced resin molded body. A knitted fabric, a unidirectional reinforcing material, and a woven fabric shape are more preferable since the fibers are less bent and strength is easily obtained, and a knitted fabric and a woven fabric shape are more preferable from the viewpoint of form stability.

The woven fabric may be a biaxial woven fabric or a triaxial woven fabric. The weaving method of the woven fabric is not particularly limited, and examples thereof include plain weave, twill weave, satin weave, weave weave, and reed.
From the viewpoint of the strength of the fiber-reinforced resin molded body, a twill weave in which the crimp ratio of the reinforcing fibers is low is more preferable.
As the knitted fabric, for example, a multi-axis insertion knitted fabric called non-crimp fabric is preferable from the viewpoint of strength, and the stitch of the knitted fabric includes tricot, combination, and the like.

<About weaving and knitting processes>
The method for obtaining the cloth-like intermediate material is not particularly limited, and can be selected according to the use and purpose.
For example, the woven fabric may use a weaving machine such as a shuttle loom, a rapier loom, an air jet loom, a water jet loom, etc., and may contain mixed yarn at least partially. For example, a preferable method is a method obtained by driving a weft into a warp in which fibers including mixed yarn are arranged. Among these, a rapier loom is preferable from the viewpoint of suppressing damage of reinforcing fibers and stably obtaining a woven fabric. The width of the rapier loom is preferably 60 cm or more, more preferably 80 cm or more, and even more preferably 100 cm or more, since the tension of the fabric is stabilized and a uniform quality fabric is easily obtained. . If the width is a certain size or larger, the quality is stable, but it is preferable to set the width to be easy to use according to the yarn used. When glass fiber or carbon fiber is used for the reinforcing fiber bundle, the width is preferably 6 m or less, more preferably 5 m or less, still more preferably 4 m or less, and most preferably 3 m or less. preferable.

The knitted fabric is obtained by knitting a fiber containing a composite yarn at least partially using a knitting machine such as a circular knitting machine, a flat knitting machine, a tricot knitting machine, or a Raschel knitting machine.
Non-woven fabric is a sheet-like fiber assembly called a web made of fibers containing at least a part of composite yarn, followed by physical action such as a needle punch machine, stitch bond machine, column flow machine, etc. It is obtained by bonding fibers with an agent.
Regarding the form of other intermediate materials, the method described in JP-A-2015-101794 can be used as appropriate.

  In the present invention, the step of obtaining a woven fabric or a knitted fabric is preferably performed in a state in which the reinforcing fibers contain liquid. By handling in a liquid-containing state, not only fuzz can be prevented, but also the straightness of the reinforcing fibers in the woven fabric and knitted fabric can be increased, and as a result, the strength of the molded body can be increased. From the relationship between strength and handleability, the liquid content is preferably 0.1 to 5% by mass, more preferably 0.2 to 4% by mass, and 0.3 to 3% by mass with respect to the reinforcing fiber. More preferably.

  The reinforcing fiber may be liquid-impregnated at any timing, may be a step of manufacturing a mixed fiber, may be performed in a state in which the mixed fiber is manufactured and wound, or may be separated after winding. A liquid addition step may be provided as a step. Further, it may be performed in a warping process as a preparation process for weaving or knitting, may be performed in a warp or threading stage, or may be performed immediately before the weft is driven. It is preferable from the viewpoints of strength and impregnation that a reinforcing fiber is contained before the mixed fiber is produced, the amount of liquid is adjusted at the time of mixing, and the weaving and knitting processes are performed.

  In the present invention, after the woven fabric or the knitted fabric is manufactured, the impregnation property can be improved by immersing these fabrics in the liquid, and the interfacial strength and the strength of the molded body can be increased. The cloth at this time may be composed only of reinforcing fibers, or may be composed of reinforcing fibers and a thermoplastic resin. The thermoplastic resin may be in the form of powder, film, woven fabric, or fiber, but from the viewpoint of shortening the distance from the reinforcing fiber, powder and fiber are preferable, and the viewpoint of fabric stability The fibrous form is preferred. The fibrous thermoplastic resin may be mixed with reinforcing fibers, or may be in a mixed woven or mixed knitted state. The state of the reinforcing fiber can be appropriately adjusted by putting a squeeze when immersed in the liquid.

<Molding method>
A fiber-reinforced resin molded body can be manufactured using the above-described mixed yarn or an intermediate material as a constituent material. In addition, the manufacturing method of a fiber reinforced resin molded object is not limited to the following, A various method is applicable.

  For example, a base material constituting a fiber reinforced resin molded body, preferably a woven or knitted base material, is cut according to a desired molded body, and the necessary number of products are laminated in consideration of the desired product thickness, Set according to the mold shape. At this time, by using the above-mentioned intermediate material, it is possible to increase the degree of freedom with respect to the mold as compared with a conventional composite plate in which a resin is impregnated with a general reinforcing fiber. Even when there is a difference, it is possible to mold with a high degree of shape freedom. A step of drying the substrate may be included before setting in the mold. The drying step can be performed before cutting and / or after cutting.

The cutting of the base material may be performed one by one or after a desired number of sheets are stacked. From the viewpoint of productivity, it is preferable to cut in an overlapped state. The cutting method may be any method, and examples thereof include a water jet, a blade press, a hot blade press, a laser, and a plotter.
After setting the substrate in the mold, the mold is closed and compressed. Then, the mold is heated to a temperature equal to or higher than the melting point of the thermoplastic resin constituting the fiber-reinforced resin molded body, and the thermoplastic resin is melted and molded. The clamping pressure is not particularly specified, but is preferably 1 MPa or more, more preferably 3 MPa or more.

  In the manufacturing process of the fiber reinforced resin molded body, an intermediate material is set in the mold and the mold is closed and pressurized, and after a predetermined time, a predetermined thermoplastic resin composition is injected and filled, and then molded. You may manufacture a hybrid molded object by joining a thermoplastic resin fiber and a predetermined thermoplastic resin composition.

<Application>
The fiber reinforced resin molded article can be suitably used for structural material applications such as aircraft, cars, construction materials, and sports equipment.
In a car application, although not limited to the following, for example, it can be used for a chassis / frame, a suspension, a drive system component, an interior component, an exterior component, a functional component, and other components.

  Specific examples and comparative examples of the present invention are shown below, but the present invention is not limited to the following examples.

<Carbon fiber (CF)>
Carbon fiber A (CF-A):
Polyvinylpyrrolidone (water-soluble component) as a sizing agent was attached to 2.9% by mass as a sizing agent on a PAN (polyacrylonitrile) carbon fiber having a single yarn diameter of 7 μm, a filament count of 12,000, and a density of 1.81 g / cm ³ . . The sizing agent was removed by immersion in water, separated into single yarn units, and a tensile test was conducted with a length of 5 cm. As a result, the load at break was 6.2 g. That is, the yarn bundle strength was calculated to be about 2000 MPa. The hydrophilicity index was 80.
Carbon fiber B (CF-B):
Bisphenol A (polyethylene glycol) ether (polyethylene glycol average) which is a water-soluble component as a sizing agent on a standard elastic modulus PAN (polyacrylonitrile) carbon fiber having a single yarn diameter of 7 μm, a filament count of 12,000, and a density of 1.81 g / cm ³ 9.3) 0.11% by mass, 0.1% by mass of a long-chain hydrocarbon compound which is a water-insoluble component was adhered. The yarn bundle had a strength of 4500 MPa and a hydrophilicity index of 12.
Carbon fiber C (CF-C):
A carbon fiber similar to the carbon fiber A was prepared except that the amount of the polyvinylpyrrolidone as a sizing agent was 0.08% by mass. The hydrophilicity index was 50.

<Thermoplastic resin fiber>
Leona (registered trademark) 470 / 144BAU (manufactured by Asahi Kasei Fibers Co., Ltd.), fineness 470 dtex, 144 single yarns Leona was used. It contained 0.9% water soluble component.

<Method of forming unidirectional material>
A test piece was obtained by the following procedure using a width of 20 mm, a length of 200 mm, and a thickness of 1 mm as targets. Two test pieces (molded bodies) were obtained by molding once. As the molding machine, a hydraulic molding machine (Shoji Co., Ltd.) having a maximum clamping force of 50 tons was used.
As shown in FIG. 2, the mixed yarn was wound around an aluminum mold. The thickness of the aluminum mold was 5 mm, and the number of times of winding was the minimum number of times that the total cross-sectional area of the mixed yarn was 20 mm ² or more. This was set in a mold having a clearance of 0.5 mm made up of COR (core) and CAV (cavity) as shown in FIG.
The temperature inside the molding machine was heated to 300 ° C., a mold was inserted, and then the mold was clamped with a clamping force of 5 MPa to perform compression molding. The molding time was 10 minutes after reaching the melting point of the main component of the matrix resin (265 ° C. in the case of polyamide 66). After rapidly cooling the mold, the mold was opened and the molded body was taken out.

<Fabric forming method>
As the molding machine, a hydraulic molding machine (Shoji Co., Ltd.) having a maximum clamping force of 50 tons was used.
A predetermined number of fabrics cut into a length of 9.5 cm and a width of 19.5 cm were charged into a mold having a length of 10 cm, a width of 20 cm, and a thickness of 2 mm. In addition, the number of sheets was the minimum number of sheets in which the volume of the fabric was 40 cm ³ or more.
The temperature inside the molding machine was heated to 300 ° C., a mold was inserted, and then the mold was clamped with a clamping force of 5 MPa to perform compression molding. The molding time was 10 minutes after reaching the melting point of the main component of the matrix resin (265 ° C. in the case of polyamide 66). After rapidly cooling the mold, the mold was opened and the molded body was taken out.

<Tensile strength, tensile modulus and strength expression rate of unidirectional material>
The test piece was vacuum-dried at 80 ° C. for 2 days before the test. Glass fiber reinforced resin (GFRP) tabs having a thickness of 2 mm, a width of 20 mm, and a length of 50 mm were attached to both ends of the test piece with an instantaneous adhesive so that the distance between the tabs was 100 mm. A strain gauge (Kyowa Dengyo KFGS-5-120-C1-23) was attached to the center of the specimen.
Using a 100 kN tensile tester manufactured by Instron and a dynamic strain meter manufactured by Kyowa Denki, a tensile test was performed at a pulling speed of 1 mm / min. The maximum load was the tensile strength (MPa), and the maximum slope of the strain-load curve was the tensile modulus.
The measured value of the tensile strength with respect to the theoretical strength calculated by the following formula was defined as the strength expression rate of the unidirectional material.
Theoretical strength = Tensile strength of reinforcing fiber bundle x Volume ratio of reinforcing fiber + Tensile strength of resin x Resin volume ratio

<Tensile strength, tensile elastic modulus and strength of fabric>
The test piece was vacuum-dried at 80 ° C. for 2 days before the test. The test piece was cut into a dumbbell shape (length 100 mm, parallel portion 6 mm, thickness 2 mm). A glass fiber reinforced resin (GFRP) tab having a thickness of 2 mm, a width of 13 mm, and a length of 22.5 mm was attached to both ends of the test piece with an instantaneous adhesive so that the distance between the tabs was 50 mm. A strain gauge (Kyowa Dengyo KFGS-5-120-C1-23) was attached to the center of the specimen.
Using a 10 kN tensile tester manufactured by Instron and a dynamic strain meter manufactured by Kyowa Dengyo Co., Ltd., a tensile test was performed at a pulling speed of 1 mm / min in the 0-90 degree direction. The maximum load was the tensile strength (MPa), and the maximum slope of the strain-load curve was the tensile modulus.
The measured value of the tensile strength with respect to the theoretical strength calculated by the following formula was used as the strength expression rate. The composite material has high strength in the fiber direction and low strength in the direction perpendicular to the fiber. In this example and the comparative example, since the density of the warp and the weft is the same, half the value of the unidirectional material is set as the theoretical strength of the tensile strength of the fabric.
Theoretical strength = (tensile strength of reinforcing fiber bundle × volume ratio of reinforcing fiber + tensile strength of resin × volume ratio of resin) / 2

<Volume content of reinforcing fiber>
Measurement was performed by the combustion method of JIS K7075.

<Unimpregnated rate>
Five sections were cut out from an arbitrary position of the molded body, embedded in an epoxy resin, and polished while taking care not to damage the reinforcing fibers. Observed with a microscope, the occupied area of the fiber bundle, the thermoplastic resin, and the voids was obtained from the obtained image, and calculated by the ratio of the void area to the total area. In addition, the measurement was performed at four places per cross section, and the median value was defined as the unimpregnated rate from the data of a total of 20 points.

<Water-soluble component amount of reinforcing fiber, thermoplastic fiber, blended yarn>
3.5 g of fiber was sampled and immersed in 60 ml of pure water and heated at 80 ° C. for 8 hours. Filtration was performed and the product was washed twice with 40 ml of pure water. All the liquids were collected and mixed to make an analysis liquid, and the components dissolved in the liquid were recovered by lyophilization, and the amount of the water-soluble component was quantified by measuring the mass.

<Amount of components adhering to reinforcing fiber and thermoplastic resin fiber in blended yarn>
The mixed yarn was cut into an appropriate length, and the reinforcing fiber and the polyamide fiber were completely separated. Water extraction was performed from each fiber, and the amount of the water-soluble component adhering to the fiber was quantified. Then, the ratio of the component (A) derived from a reinforcing fiber and the component (B) derived from a polyamide fiber was calculated using NMR, and quantified. In addition, about the component amount adhering to a reinforced fiber, it represented with the percentage with respect to the mass of a reinforced fiber, and about the component amount adhering to a thermoplastic fiber, it represented with the percentage with respect to the thermoplastic fiber mass.
Since only the reinforcing fiber of the raw material contains a water-insoluble component in Example 2, the amount was similarly determined by performing extraction with chloroform after water extraction, and the amount was combined with the amount of the water-soluble component.
Only in Example 8, the organic component (C) is added to the liquid. In this case, (C) was extracted and quantified with hexafluoro-2-propanol for the reinforcing fiber. For the polyamide fiber, the weight per length was measured, and the amount increased compared to the raw material was taken as the amount of (C).

<Percentage of mixing of reinforcing fibers in blended yarn>
The degree of mixing is defined by the ratio of the number of reinforcing fibers adjacent to the thermoplastic resin fiber to the total number of reinforcing fiber bundles. The blended yarn was cut in a state wrapped with a shrink tube, cross-section was observed with an optical microscope, and the ratio was calculated by image processing. An average value was calculated by observing 20 cross sections at arbitrary positions.

<Porosity of blended yarn>
After wrapping the mixed yarn with a shrink tube, a colored epoxy resin was poured into the tube and cured, and then cut and polished to observe the cross section.
Porosity = Area of the void / area inside the outer periphery of the mixed yarn × 100
The area of the void is the area of the colored epoxy resin inside the outer periphery of the mixed yarn, and the outer periphery of the mixed yarn is a figure drawn by a line connecting the fibers on the outermost side.

<Dispersion degree of organic matter>
The organic matter was extracted from the mixed yarn using a solvent, the mass was measured, and the ratio of the mass of the organic matter to the mass of the mixed yarn was calculated. The average value and the standard deviation were calculated in the same manner at 20 arbitrary locations, and the value obtained by dividing the standard deviation by the average value was defined as the degree of dispersion.

<Softness of blended yarn, hydrophilicity index of reinforcing fiber>
A blended yarn immediately after production was cut 20 cm, and the ends were fixed with a tape having a width of 1.5 cm to form a loop. It was hung vertically holding the part fixed with tape. If it did not become vertical at this time, it was made vertical by holding it lightly with hands. While holding the tape part, it was turned 180 degrees in the vertical direction so that the mixed yarn was standing vertically under the tape part. It was kept for 1 minute regardless of the blended yarn, and the angle at which the blended yarn hanged in the vertical direction was measured. In the case of bending in two stages, the one with the larger angle was adopted. Measurements were made on 20 arbitrary points, and the average value was calculated.
For the hydrophilicity index of the reinforcing fibers, the softness of the reinforcing fibers when dried and wet was measured in the same manner, and the difference was calculated. At the time of drying, the measurement was performed after vacuum drying at 25 ° C. for 2 hours. When wet, prepare a Japanese paper kimto towel folded in half with 50 ml of distilled water, and place the sample that has been measured when dried between the kim towel and leave it for 10 seconds without applying any load. Measured.

<Surface tension, rate of change of surface tension>
Using a contact angle measuring device DM500 manufactured by Kyowa Interface Science Co., Ltd., measurement was performed by a suspension method (Laplace method). Since the melting point of polyamide 66 is 265 ° C., the measurement was performed at 310 ° C. one minute after the droplet was formed in a nitrogen atmosphere. The melt density was calculated as 1 g / cc. In addition, since it was necessary to dry sufficiently as a pretreatment, in the case of polyamide 66, it was measured after vacuum drying at 90 ° C. for 2 days.
The organic material to be mixed with polyamide 66 (thermoplastic resin fiber) was mixed at a rate of 10% by mass using a biaxial extruder under low shear conditions. Similarly, the surface tension was measured, and the change rate of the surface tension was calculated.

<Measurement of interfacial shear stress>
Using a composite material interface property evaluation apparatus HM410 (manufactured by Toei Sangyo Co., Ltd.), measurement was performed by a microdroplet test.
A single yarn was taken out from the reinforcing fiber of the raw material or the reinforcing fiber in the mixed yarn and set in the composite material interface property evaluation apparatus. A drop in which a thermoplastic resin serving as a raw material for the thermoplastic resin fiber was melted on the apparatus was formed on the reinforcing fiber single yarn and sufficiently cooled at room temperature to obtain a sample for measurement. Set the measurement sample in the device again, sandwich the drop with the device blade, run the reinforcing fiber single yarn on the device at a speed of 0.06 mm / min, and measure the maximum pulling load f (N) when pulling out the drop. The interfacial adhesive strength τ was calculated from the following formula.
Interfacial adhesive strength τ = f / π · R · l
(F: maximum pulling load (N), R: reinforcing fiber single yarn diameter (m), l: particle diameter (m) in the pulling direction of the drop)
The interfacial shear stress change rate was calculated as a percentage of the absolute value of the difference between the interfacial shear stress of the reinforcing fiber taken from the blended yarn and the interfacial shear stress of the raw reinforcing fiber with respect to the interfacial shear stress of the raw reinforcing fiber. .

Example 1
One carbon fiber A and 10 polyamide yarns were used to draw all the yarns, and then running water of 45 ml / min was passed therethrough. After passing through a roller, it was introduced into a taslan box and subjected to taslan processing at an air pressure of 2.0 kgf / cm ² to obtain a mixed yarn. The winding yarn speed was 65 m / min, the raw carbon fiber was fed at 66 m / min, and the raw polyamide yarn was fed at 68 m / min.

(Example 2)
A mixed yarn was obtained in the same manner as in Example 1 except that carbon fiber B was used. The water-insoluble component remained in the carbon fiber even after fiber mixing.

(Example 3)
A mixed yarn was obtained in the same manner as in Example 1 except that the amount of water was 85 ml / min.

(Example 4)
A blended yarn was obtained in the same manner as in Example 1 except that the number of polyamide yarns was six.

(Example 5)
One carbon fiber A and 10 polyamide yarns were used. After all the yarns were aligned, running water of 45 ml / min was passed. It was led to an interlace type fluid entanglement nozzle (Kyocera KC-AJI-L (1.5 mm diameter, propulsion type)), and a mixed yarn was obtained at an air pressure of 0.5 kg / cm ² and a processing speed of 50 m / min.

(Example 6)
The amount of polyvinylpyrrolidone was reduced to 0.08% by mass by introducing and winding the mixed fiber obtained in Example 1 into a water tank.

(Example 7)
Carbon fiber A was used after being allowed to stand for 3 days at a humidity of 95% or less to absorb moisture. Further, even during the production of the mixed yarn, 30 ml of water was used by spraying every 1 minute and 30 seconds while humidifying the carbon fiber bobbin. One piece of carbon fiber A was allowed to pass running water at 30 ml / min. Thereafter, 10 polyamide yarns of carbon fibers were aligned, and then introduced into a taslan box and subjected to taslan processing at an air pressure of 2.0 kgf / cm ² to obtain a mixed fiber yarn. The winding yarn speed was 65 m / min, the raw carbon fiber was fed at 66 m / min, and the raw polyamide yarn was fed at 68 m / min.

(Example 8)
A mixed yarn was obtained in the same manner as in Example 7 except that a polyamide emulsion (Separsion PA200 manufactured by Sumitomo Seika Co., Ltd.) was used diluted 5 times instead of running water.
The surface tension of the polyamide 66 is 29.9 mN / m, the surface tension of the solid content in the polyamide emulsion is 35 mN / m, and the surface tension when the polyamide emulsion is mixed with the solid content of the polyamide emulsion is 31.0 mN / md. The surface tension change rate was 3.7%.
The molding time was 1 minute after reaching the melting point.

Example 9
A mixed yarn was obtained in the same manner as in Example 1 except that the amount of flowing water was set to 300 ml / min and was introduced into the Taslan box immediately after contact with the flowing water.

(Example 10)
A blended yarn was obtained in the same manner as in Example 7 except that 14 polyamide yarns were used.

(Example 11)
The mixed fiber was used in the same manner as in Example 1 except that the carbon fiber was used after drying, the winding yarn speed was 45 m / min, the carbon fiber feed was 46 m / min, and the polyamide yarn feed was 48 m / min. Obtained. Since the unraveling was not smooth, the driving speed was reduced.

(Comparative Example 1)
A mixed yarn was obtained in the same manner as in Example 1 except that water was not used. CF fluff occurred in the environment.

(Comparative Example 2)
One carbon fiber A and 10 polyamide yarns were used to draw all the yarns, and then wound up as they were. CF fluff occurred in the environment.

(Comparative Example 3)
Carbon fiber C and 10 polyamide yarns were introduced into a Taslan box, and Taslan processing was performed at an air pressure of 2.0 kgf / cm ² to obtain a blended yarn. The winding yarn speed was 65 m / min, the raw carbon fiber was fed at 66 m / min, and the raw polyamide yarn was fed at 68 m / min. CF fluff occurred in the environment.

(Comparative Example 4)
One carbon fiber A and 10 polyamide yarns were used to align all the yarns, which were then introduced into a water tank filled with water. Water was circulated with a pump at 20 m / min and opened by a water stream. The opened fibers were superposed, introduced into a water jet nozzle, supplied with 10 kg / cm ² of water, and mixed by turbulent flow treatment. The yarn speed was 20 m / min, and both carbon fiber A and polyamide yarn were fed at 22 m / min. After winding, drying was performed at 150 ° C. for 10 hours.

(Example 12)
A 4-4 twill weave was obtained from the blended yarn obtained in Example 1 at a density of 6 strands / inch using a rapier loom. The moisture content of the carbon fiber in the weaving process was 5% by mass.

(Comparative Example 5)
Using the mixed yarn obtained in Comparative Example 3, a woven fabric was obtained in the same manner as in Example 12.

  The test pieces using the mixed yarns of Examples 1 to 11 were excellent in tensile strength, tensile elastic modulus, and strength expression rate. In addition, the fabric obtained in Comparative Example 5 has a lot of fuzz, and carbon fibers are scattered in the environment. Compared with the test piece made of the fabric of Example 12, the tensile strength, tensile elastic modulus, and strength expression rate are higher. Declined.

  According to the method for producing a blended yarn, the blended yarn, and the method for producing a woven fabric or a knitted fabric according to the present invention, a reinforcing material made of a material that requires high-level mechanical properties such as various machines and structural parts of automobiles and the like. An intermediate material that can be suitably used is obtained, and has industrial applicability.

Claims (15)

  A method for producing a blended yarn comprising at least a thermoplastic resin fiber and a reinforcing fiber, wherein the thermoplastic resin fiber and the reinforcing fiber are blended in the presence of a liquid and by a fluid entanglement method using a gas. The manufacturing method of a mixed fiber including the process to do.   The method for producing a mixed fiber according to claim 1, wherein the reinforcing fiber contains 300% by mass or less of a liquid.   The method for producing a blended yarn according to claim 1 or 2, wherein the fluid entanglement method is a fluid disturbance method.   The manufacturing method of the mixed fiber of any one of Claims 1-3 in which the said reinforced fiber contains 0.1-5 mass% water-soluble component with respect to this reinforced fiber.   The method for producing a mixed yarn according to any one of claims 1 to 4, wherein the reinforcing fiber has a hydrophilicity index of 8 degrees or more.   A method for producing a blended yarn comprising at least a thermoplastic resin fiber and a reinforced fiber, wherein after the step of treating the thermoplastic resin fiber and / or the reinforced fiber with a liquid, a fluid entanglement method using a gas A method for producing a blended yarn including a blended fiber process.   The method for producing a blended yarn according to claim 6, wherein the liquid contains an organic substance.   The method for producing a blended yarn according to claim 7, wherein a rate of change in surface tension of the thermoplastic resin fiber is 30% or less when 10% by mass of the organic substance is mixed with respect to the thermoplastic resin fiber.   The method for producing a blended yarn according to any one of claims 6 to 8, wherein the liquid recovered in the blending step by the fluid entanglement method is mixed with the liquid in the step of treating with the liquid.   A mixed yarn composed of at least a thermoplastic resin fiber and a reinforced fiber, including at least two kinds of organic substances, and the two or more kinds of organic substances adhere to both the reinforced fibers and the thermoplastic resin fibers. Blended yarn.   The blended yarn according to claim 10, wherein a dispersion degree of the organic matter on the surfaces of the reinforcing fiber and the thermoplastic resin fiber is 5% or more.   The blended yarn according to claim 10 or 11, wherein the blended yarn has a softness of 20 degrees or more.   The mixed yarn according to any one of claims 10 to 12, wherein the porosity of the mixed yarn is 20% or more.   The mixed fiber according to any one of claims 10 to 13, wherein the total amount of the organic matter is less than 2% by mass with respect to the mixed fiber. A method for producing a woven fabric or a knitted fabric comprising at least a thermoplastic resin and a reinforcing fiber, wherein the liquid content of the reinforcing fiber in the reinforcing fiber weaving step is 0.1 to 5% by mass. Method.