JP2007224474A - Primary base fabric for tufted carpet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a primary base fabric for tufted carpet, enabling good tufting work without causing the delamination of the base fabric by tufting, generating little damage on the primary fabric after the tufting treatment and keeping sufficient rigidity and mechanical strength. <P>SOLUTION: The primary base fabric for tufted carpet is composed of a filament nonwoven fabric composed of a high-melting thermoplastic polymer and a low-melting thermoplastic polymer and has partly hot-pressed parts, and the parallel light transmittance of the filament nonwoven fabric is ≥4%. Preferably, the single fiber fineness of the filament is 10-20 dtex and the basis weight of the nonwoven fabric is 60-120 g/m<SP>2</SP>. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a primary base fabric for tufted carpet made of a long fiber nonwoven fabric.

  The tufted carpet is generally obtained by passing a pile yarn by tufting (tufting process) into a primary base fabric for tufted carpet and then backing (backing process). Moreover, after passing through a tufting process, it may pass through a dyeing process. The primary base fabric for carpets has a strength (stress) that is not easily deformed by a load applied during the tufting process or dyeing process, and a tufting property that prevents the base fabric from being broken by the penetration of the tufting needle in the tufting process. Required.

As a primary base fabric for tufted carpet, a long-fiber non-woven fabric is often used. For example, Patent Document 1 is a mixture of a long fiber made of a low-melting polymer and a long fiber made of a high-melting polymer. A base fabric is disclosed which is partially thermocompression bonded to a long-fiber nonwoven fabric by an embossing roll and bonded and fixed by an impregnated binder resin. Since it is partially thermocompression-bonded and bonded and fixed with a binder resin, its strength as a base fabric is high. However, in order to further improve the strength, if the amount of the binder resin attached is increased, the strength of the base fabric itself is improved, but it becomes very hard. When tufting such a base fabric, the tuft needle The resistance when penetrating the base fabric is large and difficult to penetrate, resulting in poor tufting. Moreover, since it is firmly bonded and fixed by the binder resin, the degree of freedom of the fibers is small, many fibers are cut by the penetration of the tuft needle, and the strength retention after the tuft is extremely lowered.
Japanese Patent No. 2947646

  The present invention solves the above-mentioned problem, and can be satisfactorily performed without causing delamination of the base fabric due to tufting, and after the tufting process, the primary base fabric is less damaged and sufficient. It is an object of the present invention to provide a primary base fabric for tufted carpet that can maintain high rigidity and mechanical strength.

  The inventors of the present invention have arrived at the present invention as a result of intensive studies to achieve the above-mentioned problems.

  That is, the present invention comprises a long-fiber nonwoven fabric composed of a thermoplastic high-melting polymer and a thermoplastic low-melting polymer, and the long-fiber nonwoven fabric has a thermocompression bonding part that is partially thermocompression bonded. The gist of the primary base fabric for tufted carpet is characterized in that the parallel light transmittance of the fiber nonwoven fabric is 4% or more.

  Hereinafter, the present invention will be described in detail.

  The primary base fabric for tufted carpet of the present invention is composed of a long-fiber nonwoven fabric composed of a thermoplastic high-melting polymer and a thermoplastic low-melting polymer.

  In the present invention, as the thermoplastic polymer, typically, a polyester polymer such as polyethylene terephthalate, polybutylene terephthalate, isophthalic acid copolymerized polyethylene terephthalate, a polyamide polymer such as nylon 6 and nylon 66, polyethylene, Examples thereof include polyolefin polymers such as polypropylene, and the like may be a blend or copolymer of these polymers.

  The combination of the high melting point polymer and the low melting point polymer is preferably compatible with each other. If both polymers are incompatible with each other, when using a composite fiber of both polymers, interfacial peeling or splitting occurs at the interface between the two polymers in the composite cross-sectional form, It is easy to induce various obstacles. Also, in the case of a long-fiber nonwoven fabric in which both polymers are incompatible with each other and fibers made of the respective polymers are mixed, the thermal bond strength tends to be inferior, and the thickness direction of the nonwoven fabric is affected by the impact of the tufting process. It becomes easy to peel off.

  The difference in melting point between the high melting point polymer and the low melting point polymer is preferably 15 ° C. or more. More preferably, it is 20 ° C. or higher. When the difference in melting point is less than 15 ° C., the high-melting polymer is softened or melted when heat-welding using a heat-welding device, and the softening or melting of fibers adheres to the embossing roll that is the heat-welding device. In addition to impairing the properties, the entire nonwoven fabric is film-formed, and when the tuft needle penetrates the base fabric in the tufting process, the film-formed fibers are easily cut. By making the melting point difference between them 15 ° C. or more, only the low melting point polymer is softened or melted to function as an adhesive between the fibers, and the high melting point polymer is not affected by heat and maintains the fiber form. As a result, it is possible to obtain a primary base fabric that is less damaged in the tufting process and excellent in mechanical strength.

  As a combination of the high melting point polymer and the low melting point polymer, for example, the high melting point polymer is a homopolymer, the low melting point polymer is a polymer constituting the high melting point polymer as a main repeating unit, and other components are copolymerized. It is preferable that it is a copolymerized polymer. Specific examples include high-melting point polyester / low-melting point copolymer polyester, high-melting point polyamide / low-melting point copolymer polyamide, polypropylene / propylene ethylene copolymer, and polypropylene / polyethylene. In the present invention, a combination of copolymerized polyesters having polyethylene terephthalate / ethylene terephthalate as a main repeating unit is preferable in consideration of mechanical strength and the like.

  The high melting point polymer and the low melting point polymer may be any of a matting agent, a pigment, a flameproofing agent, an antifoaming agent, an antistatic agent, an antioxidant, an ultraviolet absorber, etc., as long as the object of the present invention is not impaired. These additives may be added.

  The long fiber nonwoven fabric in the present invention is composed of a high melting point polymer and a low melting point polymer. Specifically, a nonwoven fabric in which fibers made of a low melting point polymer and fibers made of a high melting point polymer are mixed ( Mixed fiber non-woven fabric), and non-woven fabric composed of a composite fiber in which a low melting point polymer and a high melting point polymer are combined.

  In the case of a mixed fiber nonwoven fabric, it is preferable that the long fibers made of the low melting point polymer exist in a ratio of 20 to 40% by mass. By setting the ratio of the long fibers made of the low melting point polymer to 20% by mass or more, the amount of the low melting point polymer functioning as an adhesive can be sufficiently secured to sufficiently bond the fibers to each other. The delamination hardly occurs even by the impact of the tuft needle in the process. On the other hand, by setting the upper limit to 40% by mass or less, the amount of fibers made of a high melting point polymer that maintains the fiber form is ensured, and the nonwoven fabric has excellent mechanical strength. In addition, the amount of the low-melting point polymer formed into a film by softening or melting is limited, and damage to the base fabric due to fiber cutting is suppressed when the tuft needle penetrates the base fabric, and the strength of the base fabric after tufting is maintained. The

  In the case of a nonwoven fabric composed of a composite fiber in which a high-melting polymer and a low-melting polymer are combined, a composite form in which the low-melting polymer occupies a part of the fiber surface is used. In consideration of the thermal adhesive strength between the layers of the nonwoven fabric, it is preferable that the low melting point polymer is composited so as to occupy 15% or more of the fiber surface. The composite form includes a side-by-side type in which a high melting point polymer and a low melting point polymer are bonded together, a core-sheath type in which a high melting point polymer forms a core and a low melting point polymer forms a sheath, a high melting point Examples thereof include a multi-leaf type (cross-sectional shape as shown in FIG. 1) in which a polymer forms a core and a large number of leaves made of a low-melting polymer are arranged so as to surround the core. In the case of the multileaf type, the number of leaves is 1 or more, preferably 2 to 8. In the multi-leaf type composite fiber, the leaf portion made of the low melting point polymer is present in a plurality of convex shapes on the fiber surface, and the surface area of the low melting point polymer that is an adhesive component is increased. Therefore, a sufficiently high adhesive strength can be obtained without applying a high pressure during the heat-welding process, and a base fabric having a high tensile strength and a high tensile stress can be obtained. In addition, since the low melting point polymer protrudes in a convex shape on the fiber surface, the melted or softened low melting point polymer tends to enter the gap between the fibers during the heat-welding process, and the low melting point weight is reduced in the gap between the fibers. Since the coalescence is embedded and not only the strength in the longitudinal and transverse directions of the nonwoven fabric but also the strength in the thickness direction of the nonwoven fabric is improved, delamination does not easily occur in the thickness direction of the primary base fabric in the tufting process.

  The composite ratio (% by mass) of the high melting point polymer and the low melting point polymer in the composite fiber is preferably 80/20 to 40/60 (high melting point polymer / low melting point polymer). By setting the composite ratio of the low melting point polymer to 60% by mass or less, the amount of the low melting point polymer is not excessively increased, and the operability due to the fiber melt adhering to the hot roll in the hot pressing process. The required performance such as the mechanical strength of the primary base fabric can be maintained without deteriorating. On the other hand, when the composite ratio of the low melting point polymer is 20% by mass or more, the adhesive strength between the fibers due to the low melting point polymer can be maintained, and the mechanical properties of the resulting nonwoven fabric are improved. Further, delamination hardly occurs due to the impact of the tuft needle in the tufting process.

  The long fiber nonwoven fabric of the present invention has a parallel light transmittance of 4% or more. Parallel light transmittance is the light that has passed through the sample with respect to the total incident light quantity when light is transmitted through the sample, and does not diffuse into the fibers that make up the nonwoven fabric. It is the ratio of the amount of light that has advanced. Therefore, a non-woven fabric having a parallel light transmittance of 4% or more indicates that 4% or more of light has traveled straight without hitting the fiber with respect to the total incident light quantity, and a gap in which light travels straight, that is, a non-woven fabric. When the plane is viewed from the direction perpendicular to the plane (thickness direction), there are certain places where fibers are not substantially present. In the present invention, the ratio of the tuft needle penetrating through the portion where the fiber is not present in the tufting process by providing the portion where the fiber is not substantially present in the direction perpendicular to the plane (thickness direction). When the tuft needle penetrates, the constituent fibers of the non-woven fabric existing around the tuft needle are easy to escape, prevent direct piercing into the constituent fibers and damage caused by being damaged, and delamination It is difficult to occur, and the rigidity and mechanical strength of the primary base fabric after tufting can be maintained. Considering damage to the primary base fabric, it is preferable that the parallel light transmittance is large. However, increasing the parallel light transmittance also reduces the abundance ratio of the fibers, and considering the mechanical strength, The upper limit of the transmittance is preferably about 12%. The parallel light transmittance can be calculated by subtracting the diffuse transmittance (Df) from the total light transmittance (Tt). The total light transmittance is the ratio of the light transmitted through the sample to the total incident light amount when light is transmitted through the sample. The diffuse transmittance is the ratio of the sample to the total incident light amount. It is the ratio of the amount of light that has been transmitted and diffused by hitting the fibers that make up the nonwoven fabric.

  In general, non-woven fabrics are not formed by bundling a plurality of single fibers like the yarns that make up a woven or knitted fabric, but are formed by laminating individual single fibers without being bundled and spreading them apart. Therefore, there are very few places where no fiber exists in the direction perpendicular to the entire nonwoven fabric plane. Furthermore, a mechanical strength higher than a certain level as used for a carpet primary base fabric is required, and a weight per unit size greater than a certain level is required in consideration of the holding and gripping properties of the implanted tuft yarn. Therefore, in the nonwoven fabric that can be used for the primary base fabric, there are many overlapping fibers, and there are very few places where the fibers do not exist in the vertical direction on the nonwoven fabric plane. In the present invention, in order to make the parallel light transmittance 4% or more while maintaining a specific basis weight to be described later, that is, in order to provide a portion where fibers are not substantially present on the nonwoven fabric plane, Examples thereof include making the fibers constituting the nonwoven fabric have a specific single yarn fineness, and securing a void by concentrating a part of the fibers to increase the apparent fineness.

  The single yarn fineness of the fibers constituting the nonwoven fabric of the present invention is preferably 10 to 20 dtex. When it is 10 dtex or more, it is possible to provide a portion where no fiber exists on the nonwoven fabric plane. Moreover, since the single yarn fineness is large, it is difficult to be damaged when it comes into contact with the tuft needle, and it becomes a primary base fabric excellent in rigidity and mechanical strength. On the other hand, if it exceeds 20 dtex, the parallel light transmittance becomes larger, and it is preferable in consideration of the damage caused by the penetration of the tuft needle. However, depending on the basis weight, the number of constituent fibers is relatively reduced, so that the mechanical strength is maintained. It tends to be difficult. In addition, when using a mixed-fiber nonwoven fabric as a long-fiber nonwoven fabric, it is preferable that the single yarn fineness of the fiber which consists of a high melting point polymer mainly responsible for maintenance of mechanical strength shall be 10-20 dtex.

It is preferable that the fabric weight of the nonwoven fabric of this invention is 60-120 g / m < ² >. By setting it to 60 g / m ² or more, the strength of the base fabric can withstand the mass of the pile added in the tufting process, and it is difficult for slack and elongation to occur due to the weight of the living machine. Moreover, the planted tuft yarn can be satisfactorily held. When the basis weight exceeds 120 g / m ² , the number of constituent fibers is relatively increased. Therefore, it is difficult to provide a portion where no fiber exists on the nonwoven fabric plane, and when the tuft needle penetrates, the fiber is easily damaged. In addition, when using for the carpet which the pile weight given by a tuft process is remarkably large, especially a high-class carpet etc., it is a thing with a fabric weight exceeding 120 g / m < ² >, and a larger single yarn fineness (20 dtex) And a non-woven fabric having a parallel light transmittance of 4% or more.

  The long fiber nonwoven fabric of the present invention has a thermocompression bonding part that is partially thermocompression bonded. This thermocompression bonding part is formed by passing through a thermocompression bonding apparatus comprising a pair of embossing rolls or an embossing roll and a flat roll. A non-woven fabric that retains the shape of each other and has excellent dimensional stability and rigidity. A nonwoven fabric excellent in dimensional stability and rigidity can be suitably used as a primary base fabric for tile carpets in particular.

  In addition, the places other than the thermocompression bonding part are in a state where fibers are deposited and are non-compression bonding parts that are not substantially affected by heat. The ratio of the total thermocompression bonding portion to the total area of the nonwoven fabric (thermocompression bonding rate) is preferably about 3 to 30%, and more preferably 8 to 25%. The reason why 8 to 25% is more preferable is that when it is 8% or more, dimensional stability and mechanical strength are improved, and sufficient strength can withstand tensile stress during secondary processing such as tufting, dyeing, and backing. Can be held. On the other hand, by setting the ratio to 25% or less, fibers that are not affected by heat existing between the crimping parts (non-crimping part) can maintain an appropriate degree of freedom. This is because the fibers are not easily cut by force and frictional force, and the rigidity and mechanical strength can be maintained well.

Various shapes such as round, oval, rhombus, triangle, T shape, well shape, rectangle, square, etc. are adopted for the thermocompression bonding portion, and the individual area may be about 0.1 to 1.0 mm ^2. That's fine. Further, in addition to the form in which the dotted crimping parts are scattered, a linear or wavy crimping part may be provided.

  The non-woven fabric constituting the primary base fabric of the present invention obtains a long fiber having a desired single yarn fineness by a known spunbond method, and deposits this to an embossing device comprising a pair of embossing rolls or an embossing roll and a flat roll. It can be obtained by forming a thermocompression bonding part.

  In order to produce a tufted carpet using the primary base fabric of the present invention, a pile yarn may be tufted into the primary base fabric. As the pile yarn, nylon yarn, polypropylene yarn, polyester yarn or the like is used.

  A backing agent may be provided on the back of the tufted carpet in which the pile yarn is implanted in order to fix the pile yarn and to maintain the shape of the tufted carpet. Examples of the backing agent include polyvinyl chloride paste and polyethylene.

  Since the parallel light transmittance of the nonwoven fabric constituting the primary base fabric of the tufted carpet of the present invention is 4% or more, there is a portion where fibers are not substantially present on the plane of the nonwoven fabric (base fabric). The tuft needle has a high ratio of penetrating the part where no fiber is present, and the fiber is easy to escape when the tuft needle penetrates, and prevents damage caused by being directly stuck into the fiber constituting the nonwoven fabric or being damaged Therefore, the primary base fabric after tufting hardly causes delamination and can maintain the rigidity and mechanical strength of the primary base fabric after tufting. In addition, since it can prevent damage due to tufts, it is rigid enough to withstand even when a tuft error is detected and tuft yarn is pulled out and tufted again and partially corrected by tufting. Have mechanical strength.

Hereinafter, the present invention will be described specifically by way of examples. In addition, the measurement and evaluation in an Example were performed with the following method.
(1) Melting point of polymer (° C.): Melting point is the temperature that gives the maximum value of the melting endothermic peak measured at a heating rate of 20 ° C./min using a DSC-7 type differential scanning calorimeter manufactured by PerkinElmer. It was.
(2) Intrinsic viscosity of polyester: 0.5 g of a sample was dissolved in 100 ml of a mixed solvent having an equal mass ratio of phenol and ethane tetrachloride and measured by a conventional method at a temperature of 20 ° C.
(3) Weight per unit area (g / m ² ): 10 pieces of 50 cm × 50 cm sample pieces were cut from the standard condition sample, the mass of each sample piece was weighed, and the average value was converted into the mass per unit square meter. (G / m ² ).
(4) Parallel light transmittance (Pt): Measured using a turbidity / cloudiness meter (HazeMeter NDH2000 manufactured by Nippon Denshoku Industries Co., Ltd.). In the measurement, an average value of 5 samples (2 measurement locations per sample) was obtained.
(5) Tensile strength (N / 5 cm width): Using a Tenshiron RTM-500, a constant-speed extension type testing machine manufactured by Toyo Baldwin Co., Ltd., a strip-shaped sample piece having a width of 5 cm and a length of 30 cm is gripped at a tensile rate of 20 cm. It measured according to the strip method as described in JIS L1096 at 20 cm / min. And it measured about 10 sheets each about MD direction (machine direction) and CD direction (direction orthogonal to a machine direction), calculated | required the average value of these, and made this tensile strength.

Example 1
Polyethylene terephthalate (melting point 260 ° C., intrinsic viscosity 0.68) as a high melting point polymer, and copolymerized polyester (melting point 230 ° C., intrinsic viscosity 0.69%) copolymerized with ethylene terephthalate as isophthalic acid as a low melting point polymer. ) Was prepared. These polymers are obtained by using a die having a multi-leaf type composite cross section having six leaf parts (a multi-leaf cross-sectional shape as shown in FIG. 1 is obtained), a spinning temperature of 290 ° C., a composite ratio (high melting point). The polymer / low melting point polymer) was spun under the condition of 80/20 (mass ratio). After cooling the spun yarn, it is taken up at a speed of 5000 m / min by air soccer and the fineness of the composite long fiber is made 10 decitex, then opened by a known method and collected on the moving collection surface. The non-woven web was deposited, and the non-woven web was subjected to thermocompression bonding using a thermocompression bonding apparatus composed of an embossing roll and a flat roll at a pressure bonding temperature of 205 ° C. and a pressure bonding area ratio of 13%. The obtained fabric for tufted carpet had a basis weight of 90 g / m ² , a tensile strength of 115.0 N / 5 cm width, and a parallel light transmittance of 4.3%.

Example 2
Polyethylene terephthalate (melting point 260 ° C., intrinsic viscosity 0.68) as a high melting point polymer, and copolymerized polyester (melting point 230 ° C., intrinsic viscosity 0.69%) copolymerized with ethylene terephthalate as isophthalic acid as a low melting point polymer. ) Was prepared. These polymers were prepared using a die having a leaf portion of 6 in a multileaf composite cross section (a multileaf cross section shape as shown in FIG. 1 was obtained), a spinning temperature of 290 ° C., a composite ratio (high melting point polymer / low Spinning was performed under the condition that the melting point polymer) was 70/30 (mass ratio). After cooling the spun yarn, it is taken up by air soccer at a speed of 5000 m / min, and the fineness of the composite continuous fiber is set to 13 dtex, then opened by a known method, and collected on the moving collection surface. The web was deposited, and the web was hot-welded under the conditions of a pressure-welding temperature of 210 ° C. and a pressure-contact area ratio of 13% using a heat-welding apparatus comprising an embossing roll and a flat roll. The basis weight of the obtained tufted carpet was 90 g / m ² , the tensile strength was 95.0 N / 5 cm width, and the parallel light transmittance was 8.6%.

Example 3
Polyethylene terephthalate (melting point 260 ° C., intrinsic viscosity 0.68) as a high melting point polymer, and copolymerized polyester (melting point 230 ° C., intrinsic viscosity 0.69%) copolymerized with ethylene terephthalate as isophthalic acid as a low melting point polymer. ) Was prepared. These polymers were prepared using a die having a leaf portion of 6 in a multileaf composite cross section (a multileaf cross section shape as shown in FIG. 1 was obtained), a spinning temperature of 290 ° C., a composite ratio (high melting point polymer / low Spinning was performed under the condition that the melting point polymer) was 70/30 (mass ratio). After cooling the spun yarn, it is taken up at a speed of 5000 m / min by air soccer and the fineness of the composite long fiber is made 10 decitex, then opened by a known method and collected on the moving collection surface. The web was deposited, and the web was hot-welded under the conditions of a pressure-welding temperature of 205 ° C. and a pressure-contact area ratio of 13% in a heat-welding apparatus comprising an embossing roll and a flat roll. The basis weight of the obtained tufted carpet was 70 g / m ² , the tensile strength was 80.5 N / 5 cm width, and the parallel light transmittance was 5.1%.

Example 4
Polyethylene terephthalate (melting point 260 ° C., intrinsic viscosity 0.68) as a high melting point polymer, and copolymerized polyester (melting point 230 ° C., intrinsic viscosity 0.69%) copolymerized with ethylene terephthalate as isophthalic acid as a low melting point polymer. ) Was prepared. These polymers were spun at a spinning temperature of 290 ° C. and a mixing ratio ratio (high melting point polymer / low melting point polymer) of 80/20 (mass ratio) using spinning holes with different round cross-sections from the die. Spun out. After cooling the spun yarn, it is taken up by air soccer at a speed of 5000 m / min, the fineness of the fiber made of the melting point polymer is set to 13 dtex, and the fineness of the low melting point polymer is set to 5 dtex, and then by a known method. The fiber is opened and collected on a moving collection surface and deposited into a web, and the web is heated and welded with an embossing roll and a flat roll under a pressure welding temperature of 205 ° C. and a pressure welding area ratio of 25%. Hot pressing was performed. The basis weight of the obtained tufted carpet was 90 g / m ² , the tensile strength was 93.5 N / 5 cm width, and the parallel light transmittance was 7.4%.

Comparative Example 1
Polyethylene terephthalate (melting point 260 ° C., intrinsic viscosity 0.68) as a high melting point polymer, and copolymerized polyester (melting point 230 ° C., intrinsic viscosity 0.69%) copolymerized with ethylene terephthalate as isophthalic acid as a low melting point polymer. ) Was prepared. These polymers were prepared using a die having a leaf portion of 6 in a multileaf composite cross section (a multileaf cross section shape as shown in FIG. 1 was obtained), a spinning temperature of 290 ° C., a composite ratio (high melting point polymer / low Spinning was performed under the condition that the melting point polymer) was 70/30 (mass ratio). After cooling the spun yarn, it is taken up by air soccer at a speed of 5000 m / min and the fineness of the composite continuous fiber is set to 4.4 dtex, then opened by a known method, and captured on the moving collection surface. The webs were collected and deposited to form a web, and the web was subjected to thermal welding under the conditions of a pressure welding temperature of 205 ° C. and a pressure welding area ratio of 13% using a heat pressure welding apparatus composed of an embossing roll and a flat roll. The basis weight of the obtained tufted carpet was 90 g / m ² , the tensile strength was 107.5 N / 5 cm width, and the parallel light transmittance was 0.9%.

Comparative Example 2
Polyethylene terephthalate (melting point 260 ° C., intrinsic viscosity 0.68) as a high melting point polymer, and copolymerized polyester (melting point 230 ° C., intrinsic viscosity 0.69%) copolymerized with ethylene terephthalate as isophthalic acid as a low melting point polymer. ) Was prepared. These polymers were spun at a spinning temperature of 290 ° C. and a blend ratio (high melting point polymer / low melting point polymer) of 80/20 (mass ratio) by using spinning holes with different round cross-sections from the die. Spun out. After cooling the spun yarn, it is taken up at a speed of 5000 m / min by air soccer, and the fineness of the fiber made of the melting point polymer is set to 5 dtex and the fineness of the low melting point polymer is set to 3 dtex, and then by a known method. The fiber is opened, collected on a moving collection surface, and deposited into a web, and the web is heated and welded with an embossing roll and a flat roll under a pressure welding temperature of 205 ° C. and a pressure welding area ratio of 13%. Hot pressing was performed. The basis weight of the obtained tufted carpet was 90 g / m ² , the tensile strength was 121.5 N / 5 cm width, and the parallel light transmittance was 1.4%.

<Evaluation after tufting>
It evaluated after performing the following tufting to the primary base fabric for tufted carpets obtained in Examples 1-4 and Comparative Examples 1,2.

  That is, using pile yarn made of 3080 dtex nylon crimped yarn for the base fabric, tufting is performed under the conditions of 10 gauges / 2.54 cm, 10 stitches / 2.54 cm, and a loop pile height of 6 mm. To obtain a taft machine. The pile was removed from the obtained raw machine, and the following measurement and evaluation were performed using the base fabric from which the pile had been removed as a base fabric after tufting.

(1) Rigidity of tufting machine: A sample piece having a length of 50 cm and a width of 10 cm was prepared from the obtained tufting machine. At this time, the sample piece was collected so that the longitudinal direction of the sample piece was the CD direction of the living machine. The obtained sample piece is placed on a table with the pile surface (1) facing up (see FIG. 2A), and then the pile surface is placed so that one end in the longitudinal direction of the sample piece is in contact with the other end. The sample piece was bent so as to be inside (see FIG. 2B), and the height of the highest position of the bent sample piece was measured to evaluate the rigidity of the tufting machine. The higher the height of the bent sample piece, the higher the rigidity. In the present invention, a specimen having a thickness of 30 mm or more has a good rigidity and can be suitably used for a tile carpet.

(2) Tensile strength retention after tufting: From the obtained tufting machine, the pile yarn was all pulled out, and the tensile strength was measured by the method described in (5) Tensile strength described above for the base fabric after tufting. . In the measurement, in the dyeing process after the tuft, the backing process, and the like, particularly in the CD direction, a strong force is required. Subsequently, the retention rate was calculated by the following formula. Further, the following four levels of tuft retention were evaluated from the obtained retention rates.
Retention rate after tuft (%) = Tensile strength of base fabric after tufting / Tensile strength of base fabric in three stages ◎: 40% or more ○: 30% or more, less than 40% Δ: 15% or more, less than 30% ×: Less than 15%

(3) Evaluation of delamination: From the obtained tufting machine, all the pile yarn was pulled out, and the state of the layer was visually observed on the base fabric after tufting from which the pile yarn was removed, and the following evaluation was performed.
◎: No delamination at all ○: Slight layer separation was observed ×: Layer separation or separation

The primary base fabrics for tufted carpets of Examples 1 to 4 had excellent mechanical strength, all had good tuft properties, and no delamination occurred. Moreover, the strong holding property after a tuft was also high, and there was little damage by needle penetration at the time of a tuft.

  On the other hand, in Comparative Examples 1 and 2, compared with the Examples of the present invention, the strength retention was low after tufting, and there was much damage due to needle penetration during tufting.

It is the schematic which shows the cross-sectional shape of the composite fiber (multileaf type) used for this invention. In this invention, it is a schematic sectional drawing at the time of evaluating rigidity.

Explanation of symbols

1: Core part 2: Leaf part 3: Pile surface 4: Primary base fabric

Claims (2)

It consists of a long-fiber nonwoven fabric composed of a thermoplastic high-melting-point polymer and a thermoplastic low-melting-point polymer, and the long-fiber nonwoven fabric has a thermocompression bonding part that is partially thermocompression-bonded, and the parallel light transmittance of the long-fiber nonwoven fabric Primary base fabric for tufted carpet, characterized in that is 4% or more. Single yarn fineness of 10-20 dtex filaments composing the long-fiber nonwoven fabric, tufted carpet primary backing according to claim 1, wherein the basis weight is 60~120g / m ^2.