JP5284874B2 - Automotive interior materials - Google Patents

Description

  The present invention relates to a lightweight fiber sheet excellent in lightness and permeation resistance, and a fiber product using the lightweight fiber sheet.

  Fiber sheets using fiber materials such as synthetic fibers are used in various applications such as houses, railway vehicles, aircraft and automobiles, and the most suitable type is used for each application. Particularly in recent years, there has been a strong demand for further weight reduction of all materials in order to improve fuel economy, and automotive interior materials are no exception. On the other hand, the interior material is also required to have a light-proof property so that the backing material cannot be seen through in combination with the light weight, but there is a problem that the light-proof property is impaired when the weight is reduced.

  As a countermeasure for this, generally, polymers used for synthetic fibers are often transparent, and fiber products formed of synthetic fibers have the disadvantage that they are easy to see through. Thus, by generally incorporating a light hiding agent such as titanium oxide, A method of using fibers with high light shielding properties is employed (see, for example, Patent Document 1). However, there is a possibility that sufficient light-shielding property and prevention of see-through effect cannot be obtained only by adding a small amount of light shielding agent to the polymer. On the contrary, if a large amount of light-screening agent is added to the polymer, the texture of the resulting fiber may be hardened. There was a risk of significant wear. Furthermore, since the specific gravity of the light masking agent is large, the lightness of the fiber may be impaired.

  In addition, proposals have been made to increase the irregular reflection of light by providing a hollow portion or a void inside the fiber, thereby providing light shielding properties and light weight. For example, it has been proposed to include a specific amount of fine particles and fluorescent white pigment in a hollow composite fiber (see Patent Document 2). In such a method, it is necessary to increase the hollow ratio in order to develop sufficient lightness and light-shielding properties. As a result, the hollow part is easily cracked, and the hollow part is continuously in the fiber axis direction. Since it exists, it tends to be crushed by an external force, and there is a possibility that both lightness and light shielding properties may be impaired.

As described above, lightness and permeation are normally contradictory properties, and fiber sheets that have both lightness and permeation have not been proposed so far.
In addition, although it is for achieving the completely different subject from this invention, the fiber sheet using atypical cross-section fiber is known (for example, refer patent document 3).

JP-A-53-94623 JP 11-350256 A Japanese Patent Laid-Open No. 10-238661

  This invention is made | formed in view of said background, The objective is to provide the lightweight fiber sheet excellent in lightweight property and permeation-proof property, and the textiles using this lightweight fiber sheet.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventor has found that when a fiber sheet is formed using atypical short cross-section fibers, excellent permeation resistance can be obtained despite being lightweight. As a result, the present invention was completed.

Thus, according to the present invention, “a fiber sheet having a basis weight of 290 g / m ² or less, and the fiber sheet includes atypical short section fibers that simultaneously satisfy the following requirements (1) and (2) ; There is provided an automobile interior material using a lightweight fiber sheet , wherein the fiber sheet is obtained by entanglement processing of a web containing the atypical section short fibers by a needle punch method .
(1) In the single fiber cross section of the atypical section short fiber, the degree of atypia is 2.0 or more.
However, the atypical degree is a ratio D1 / D2 between the circumscribed circle diameter D1 and the inscribed circle diameter D2 of the single fiber cross section.
(2) In the single fiber cross section of the irregular cross-section short fiber, the ratio S1 / S2 between the cross-sectional area S1 and the circumscribed circle area S2 is 0.65 or less.

In that case, it is preferable that the circumscribed circle diameter of the atypical short section fiber is in the range of 10 to 100 μm. Moreover, it is preferable that the fiber length of the atypical section short fiber is in the range of 30 to 100 mm. Moreover, it is preferable that the said atypical section short fiber consists of a polyester fiber. Moreover, it is preferable that the said atypical section short fiber consists of a polymer containing a coloring agent. Moreover, it is preferable that a fiber sheet is a thing which carried out the entanglement process of the web containing the said unusual cross-section short fiber. Moreover, it is preferable that the average density of a fiber sheet is 200 kg / m < ³ > or less. Moreover, it is preferable that the permeability of a fiber sheet is 1.6 or more.

  However, the transmittance of the fiber sheet is measured using a spectrophotometer in the wavelength region of 360 to 830 nm, and the integral value T1 of the transmittance in the wavelength region is obtained from the obtained transmittance curve, and the integral of this transmittance is obtained. From the value T1 and the density M of the fiber sheet, the non-permeability per unit density ((100−T1) / M) is calculated and defined as the permeation resistance.

  ADVANTAGE OF THE INVENTION According to this invention, the lightweight fiber sheet excellent in lightweight property and permeation resistance, and the textiles using this lightweight fiber sheet are obtained. Particularly in the automobile field, both cost reduction and improvement in fuel consumption can be expected.

Hereinafter, embodiments of the present invention will be described in detail. First, the fiber sheet of the present invention is a sheet using a fiber material made of organic fibers, and has a basis weight of 290 g / m ² or less (preferably 10 to 290 g / m ² ). When the basis weight is larger than 290 g / m ² , the lightness is impaired, which is not preferable.

The fiber sheet of the present invention includes atypical short section fibers that simultaneously satisfy the following requirements (1) and (2).
(1) In the single fiber cross section of the atypical cross section short fiber, the atypical degree is 2.0 or more (preferably 2.1 to 4.0).
However, the atypical degree is a ratio D1 / D2 between the circumscribed circle diameter D1 and the inscribed circle diameter D2 of the single fiber cross section. The inscribed circle diameter is the maximum inscribed diameter. Table 1 shows the circumscribed circle and inscribed circle for the cross section, H section, atypical hollow section, round section, triangular section, and perfect circular section. The location to be shown is indicated by a broken line.
(2) In the single fiber cross section of the irregular cross-section short fiber, the ratio S1 / S2 between the cross-sectional area S1 and the circumscribed circle area S2 is 0.65 or less (preferably 0.1 to 0.6).

  Here, when the atypical degree is less than 2.0, it is not preferable because sufficient permeation resistance cannot be obtained because light easily passes through the fiber sheet. Further, when the ratio S1 / S2 is larger than 0.65, it is not preferable because sufficient permeation resistance cannot be obtained because light easily passes through the fiber sheet.

  The specific single fiber cross-sectional shape of the irregular cross-section short fiber is not particularly limited as long as the above (1) and (2) are satisfied at the same time, but there are a cross section, an H section, a flat section, a constricted flat section, etc. preferable.

  At that time, in the single fiber cross section of the irregular cross-section short fiber, the ratio H1 / D1 (degree of spread) between the width H1 (illustrated in Table 1) at the position where the width is the narrowest and the circumscribed circle diameter D1 is 0.3. The above is preferable. When the specific width H1 / D1 is smaller than 0.3, the odd-shaped cross-section short fibers are likely to be close-packed, which may make it difficult to obtain a low-density fiber sheet.

  The circumscribed circle diameter of the irregular cross-section short fiber is preferably within a range of 10 to 100 μm. If the circumscribed circle diameter is smaller than 10 μm, process stability may be impaired. On the other hand, if the circumscribed circle diameter is larger than 100 μm, the permeability and the uniformity of the appearance may be insufficient.

  In the modified short cross-section fiber, the fiber length is preferably in the range of 30 to 100 mm. If the fiber length is less than 30 mm, process stability may be impaired. On the contrary, when the fiber length is longer than 100 mm, the fibers are easily arranged in one direction and not only the permeation resistance is impaired but also the process stability may be impaired. In addition, in order to make fiber length into the range of 30-100 mm, it is good to cut fiber tow by a conventional method.

The fiber type of the irregular cross-section short fiber is not particularly limited, but polyester fiber is preferable in terms of recyclability, fiber strength, and easy kneading of a colorant as described later.
As the polyester here, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycyclohexanedimethanol terephthalate, polylactic acid (PLA) and stereocomplex polylactic acid are preferred, and polyethylene terephthalate is particularly preferred. Such polyester may be material recycled or chemically recycled polyester. Furthermore, the polyester obtained using the catalyst containing the specific phosphorus compound and titanium compound which are described in Unexamined-Japanese-Patent No. 2004-270097 and 2004-21268 may be sufficient.

  In addition, it is preferable that the atypical cross-section short fiber is a so-called original fiber formed of a polymer containing a colorant since the permeation resistance is improved. In particular, it is preferable that the atypical short section fibers are formed of polyester containing a colorant. When the original fiber is used, the color depth is further improved and a preferable appearance is obtained.

  Here, the colorant contained in the polymer may be any known colorant, such as inorganic pigments such as carbon black, titanium oxide, zinc oxide, chromium oxide, iron oxide, phthalocyanine-based, azo Organic pigments such as perinone, perinone, perylene, and anthraquinone, kaolin, calcium carbonate, aluminum oxide, silica gel, and silicon oxide can also be used. The coloring agent can be added by any known method.

  For example, in the case of polyester, a method of adding in a polymer polymerization step, a method of kneading with a base polyester not containing a dyeing agent after master pelletization, a liquid additive composition in which a dyeing agent and a liquid polyester are mixed in advance are spun. Examples thereof include a method in which static or dynamic kneading dispersion is performed after injection and addition while measuring with a gear pump or the like in the immediately preceding molten polyester flow. Among them, the method using a master pellet is preferable in consideration of contamination of the spinning device, handling property, cost, and the like.

  In addition, in the polymer that forms the atypical cross-section short fiber, a fine pore forming agent, a cationic dye dyeing agent, a thermal stabilizer, a fluorescent brightening agent, as necessary, within a range not impairing the object of the present invention, A matting agent (titanium oxide), a hygroscopic agent, or one or more inorganic fine particles may be contained.

  Moreover, it is preferable that crimping is imparted to the atypical short cross-section fibers, since the permeability is further improved. At this time, as a method for imparting crimps, spiral crimps are imparted using composite fibers obtained by bonding polymers having different heat shrinkage rates to side-by-side types, spiral crimps are imparted by anisotropic cooling, and the number of crimps is 3 Various methods such as imparting mechanical crimping by a conventional indentation crimper method so as to be ˜40 pieces / 2.54 cm (preferably 7 to 15 pieces / 2.54 cm) may be used, but the bulkiness and production cost are increased. It is optimal to provide mechanical crimping from the viewpoint of the above.

  The fiber sheet of the present invention is most preferably composed of only the above-mentioned atypical short section fibers, but may contain other fibers. At this time, the content of other fibers is preferably 50% by weight or less with respect to the weight of the fiber sheet. In addition, as such other fibers, polyester fibers as described above are preferable in view of recyclability. However, a heat in which a heat-adhesive component such as a polyurethane-based elastomer, a polyester-based elastomer, a copolymerized polyester-based polymer is arranged on the fiber surface is used. Adhesive composite short fibers, polyolefin fibers, polyamide fibers, natural fibers, carbon fibers, or a blend of these short fibers may also be used.

In the fiber sheet of the present invention, the structure of the sheet is not particularly limited, and a woven fabric or a knitted fabric may be used.
The fiber sheet of the present invention can be produced, for example, by the following production method. That is, first, a web is obtained by a conventional method using the atypical cross-section short fibers. In that case, it is preferable that the web contains 50% by weight or more of the modified cross-section short fibers because the permeability and lightness are improved.

Subsequently, a fiber sheet having a basis weight of 290 g / m ² or less is obtained by performing entanglement processing on the web. In this case, examples of the entanglement method include a needle punch method, a chemical bonding method, an air through method, a spun lace method, and an airlaid method. Among these, the needle punch method is preferable for obtaining a fiber sheet excellent in lightness.

Further, a known functional process such as a normal dyeing process, a water repellent process, a flameproof process, a flame retardant process, and a negative ion generation process may be added.
Since the fiber sheet thus obtained contains the atypical cross-section short fibers, the fiber sheet has excellent permeability even though it is lightweight. Here, the permeability of the fiber sheet is preferably 1.6 or more (preferably 1.6 to 3.0).

  However, the transmittance of the fiber sheet is measured using a spectrophotometer in the wavelength region of 360 to 830 nm, and the integral value T1 of the transmittance in the wavelength region is obtained from the obtained transmittance curve, and the integral of this transmittance is obtained. From the value T1 and the density M of the fiber sheet, the non-permeability per unit density ((100−T1) / M) is calculated and defined as the permeation resistance.

Further, in such a fiber sheet, when the average density of the fiber sheet is 200 kg / m ³ or less (more preferably 10 to 100 kg / m ³ , particularly preferably 10 to 60 kg / m ³⁾ , excellent permeation resistance is obtained. It is preferable. Since the fiber sheet of the present invention has a low basis weight, if the density of the fiber sheet is increased, light is likely to pass therethrough, and the permeation resistance may be impaired. Moreover, when it is low density, it is excellent also in manufacturing process passage property and durability of a product.

  Next, the textile product of the present invention comprises a ceiling material, a wall material, a floor material, a carpet, a partition of a living space, and an automobile interior material (ceiling material, car seat skin material, floor mat) using the fiber sheet. Or any other fiber product selected from the group consisting of: Here, such a fiber product may be configured using only the above-described fiber sheet, or a resin backing processing on the back surface, and further, various nonwoven fabric sheets on the back surface layer for improving shape stability or sound absorption, There is no problem in bonding woven or knitted fabric, urethane foam, film or the like.

Since such a fiber product uses the above-described fiber sheet, it is excellent in lightness and permeability. Particularly in the automobile field, both cost reduction and improvement in fuel consumption can be expected.
In addition, it cannot be overemphasized that the said fiber sheet is used for another use, without being limited to these textiles.

  Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited thereto.

(1) Deformation An embedding block in which a block in which fibers are embedded in an epoxy resin is subjected to metal dyeing as necessary, and a single fiber cross section is obtained by cutting in a direction perpendicular to the fiber axis with an ultramicrotome. The cross section of the single fiber was observed with a scanning electron microscope (SEM) at an arbitrary magnification of 1000 to 20000 times, and the obtained photograph was digitized. In the cross-sectional photograph, the ratio (D1 / D2) between the diameter D1 of the circumscribed circle and the diameter D2 of the inscribed circle in the single fiber cross section was calculated as the degree of irregularity.

(2) Area ratio An embedding block in which a block in which fibers are embedded in an epoxy resin is subjected to metal dyeing as necessary, and a single fiber cross section is obtained by cutting in a direction perpendicular to the fiber axis with an ultramicrotome. The cross section was observed with a scanning electron microscope (SEM) at an arbitrary magnification of 1000 to 20000, and the resulting photograph was digitized. In the cross-sectional photograph, the ratio (S1 / S2) of the cross-sectional area S1 and the circumscribed circle area S2 in the single fiber cross section was calculated under the above-mentioned conditions, and was defined as the area ratio.

(3) Degree of embedding An embedding block in which a block in which fibers are embedded in an epoxy resin is subjected to metal dyeing as necessary, and a single fiber cross section is obtained by cutting in a direction perpendicular to the fiber axis with an ultramicrotome. The cross section was observed with a scanning electron microscope (SEM) at an arbitrary magnification of 1000 to 20000, and the resulting photograph was digitized. In the cross-sectional photograph, the ratio (H1 / D1) between the diameter D1 of the circumscribed circle in the cross section of the short fiber and the height H1 set to be the lowest under the above-described conditions was calculated and defined as the degree of spread.

(4) Thickness, basis weight, density Measured according to JIS K6400.

(5) Permeability The transmittance was measured for a wavelength region of 360 to 830 nm using a spectrophotometer. The integral value T1 of the transmittance in the wavelength region was determined from the transmittance curve obtained by averaging the results of four measurements performed at different measurement locations in each sample. The non-transmittance per unit density ({100−T1} / De) was calculated from the integral value T1 of the transmittance and the density De of the sample, and used as the permeation resistance.

[Example 1]
Using a die capable of forming a cross-section fiber shown in Table 1 as the die, melt spinning and stretching of polyethylene terephthalate containing a colorant (manufactured by DIC, product names MC-034, MC-059, MC-083) are performed. After that, it was cut by a conventional method to obtain short fibers. The obtained short fiber has a cross shape as shown in Table 1 in cross-sectional shape, and has a deformed short fiber having a deformity of 2.0, an area ratio of 0.65, a spread of 0.71, a fiber diameter of 23 μm, and a fiber length of 51 mm ( (Colored gray). The deformed short fiber web was formed by carding and cross layer, and then needle punched to obtain a lightweight fiber sheet having a basis weight of 151 gr / m ² , a thickness of 3.0 mm, and an average density of 50 kg / m ³ . The fiber sheet had a sufficiently high permeability of 1.94 and was excellent in the permeability.

[Example 2]
Using a base capable of forming an H-section fiber shown in Table 1 as the base, the same polyethylene terephthalate melt spinning and stretching as in Example 1 were performed, and then cut into a short fiber by a conventional method. The obtained short fiber has an H shape whose cross-sectional shape is shown in Table 1. Short fiber (gray) having an irregularity of 2.5, an area ratio of 0.53, a spread of 0.74, a fiber diameter of 25 μm, and a fiber length of 51 mm. Color). The deformed short fiber web was formed by carding and cross layer, and then needle punched to obtain a fiber sheet having a basis weight of 153 gr / m ² , a thickness of 3.1 mm, and an average density of 49 kg / m ³ . In the lightweight fiber sheet, the permeability was sufficiently high as 1.95, and the permeability was excellent.

[Example 3]
Using a base capable of forming a modified hollow cross-section fiber shown in Table 1 as the base, the same polyethylene terephthalate as in Example 1 was melt spun and stretched, and then cut into a short fiber by a conventional method. The obtained short fiber is an irregular hollow type whose cross-sectional shape is shown in Table 1. The short fiber having an irregularity of 2.9, an area ratio of 0.57, a spread of 0.77, a fiber diameter of 24 μm, and a fiber length of 51 mm ( (Colored gray). The deformed short fiber web was formed by carding and cross layer, and then needle punched to obtain a fiber sheet having a basis weight of 151 gr / m ² , a thickness of 2.8 mm, and an average density of 54 kg / m ³ . In the lightweight fiber sheet, the permeability was sufficiently high as 1.72, and the permeability was excellent.

[Example 4]
Using a base capable of forming cross-section fibers shown in Table 1 as the base, the same polyethylene terephthalate as in Example 1 was melt-spun and stretched, and then cut by a conventional method to obtain short fibers. The obtained short fiber has a cross-shaped cross section, and has an irregularity of 2.0, an area ratio of 0.65, a spread of 0.71, a fiber diameter of 23 μm, and a fiber length of 51 mm (colored gray). )Met. Blended using 50% by weight of this irregularly shaped short fiber and 50% by weight of a round short section fiber (fiber diameter 18 μm, fiber length 51 mm, colored gray) made of ordinary polyethylene terephthalate (not containing a colorant). Then, a web of 50% of the irregular short fibers is formed by carding and cross layer, and then needle punched to obtain a lightweight fiber sheet having a basis weight of 155 gr / m ² , a thickness of 2.8 mm, and an average density of 55 kg / m ^3. It was. In the fiber sheet, the permeability was sufficiently high as 1.65, and the permeability was excellent.

[Comparative Example 1]
Using a base capable of forming a normal round cross-section fiber as the base, the same polyethylene terephthalate melt spinning and stretching as in Example 1 were performed, and then cut into a short fiber by a conventional method. The obtained short fiber has a round cross-sectional shape, a short fiber having an irregularity of 1.0, an area ratio of 1.0, a spread of 1.0, a fiber diameter of 18 μm, and a fiber length of 51 mm (colored gray). Met. The deformed short fiber web was formed by carding and cross layer, and then needle punched to obtain a fiber sheet having a basis weight of 183 gr / m ² , a thickness of 3.2 mm, and an average density of 57 kg / m ³ . The fiber sheet had a low permeability of 1.58.

[Comparative Example 2]
Using a base capable of forming a triangular cross-section fiber shown in Table 1 as the base, the same polyethylene terephthalate as in Example 1 was melt-spun and stretched, and then cut into a short fiber by a conventional method. The obtained short fiber has a triangular cross-sectional shape, a short fiber having a degree of deformity of 1.9, an area ratio of 0.68, a degree of spread of 0.74, a fiber diameter of 20 μm, and a fiber length of 51 mm (colored gray). Met. The deformed short fiber web was formed by carding and cross layer, and then needle punched to obtain a fiber sheet having a basis weight of 154 gr / m ² , a thickness of 2.6 mm, and an average density of 59 kg / m ³ . The fiber sheet had a low permeability of 1.53.

[Comparative Example 3]
Using a base capable of forming a perfect circular hollow cross-section fiber shown in Table 1 as the base, the same polyethylene terephthalate as in Example 1 was melt spun and stretched, and then cut into a short fiber by a conventional method. The obtained short fiber has a perfect circular hollow cross-sectional shape, a short fiber (gray color) having an irregularity of 2.8, an area ratio of 0.88, a spread of 1.0, a fiber diameter of 22 μm, and a fiber length of 51 mm. Coloration). The deformed short fiber web was formed by carding and cross layer, and then needle punched to obtain a fiber sheet having a basis weight of 152 gr / m ² , a thickness of 2.4 mm, and an average density of 63 kgr / m ³ . The fiber sheet had a low permeability of 1.41.

  ADVANTAGE OF THE INVENTION According to this invention, the lightweight fiber sheet excellent in lightweight property and permeation resistance, and the textiles using this lightweight fiber sheet are provided, The industrial value is very large.

Claims (7)

A fiber sheet having a basis weight of 290 g / m ² or less, wherein the fiber sheet includes atypical short section fibers that simultaneously satisfy the following requirements (1) and (2) , and the fiber sheet has the atypical cross section length: An automotive interior material using a lightweight fiber sheet , wherein a web containing fibers is entangled by a needle punch method .
(1) In the single fiber cross section of the atypical section short fiber, the degree of atypia is 2.0 or more.
However, the atypical degree is a ratio D1 / D2 between the circumscribed circle diameter D1 and the inscribed circle diameter D2 of the single fiber cross section.
(2) In the single fiber cross section of the irregular cross-section short fiber, the ratio S1 / S2 between the cross-sectional area S1 and the circumscribed circle area S2 is 0.65 or less. The automobile interior material according to claim 1, wherein a circumscribed circle diameter of the irregular cross-section short fiber is within a range of 10 to 100 μm. The automobile interior material according to claim 1 or 2, wherein a fiber length of the modified cross-section short fiber is in a range of 30 to 100 mm. The automobile interior material according to any one of claims 1 to 3, wherein the odd-shaped short section fibers are made of polyester fibers. The automobile interior material according to any one of claims 1 to 4, wherein the atypical short section fiber is made of a polymer containing a colorant. The automobile interior material according to any one of claims 1 to 5, wherein an average density of the fiber sheet is 200 kg / m ³ or less . The automobile interior material according to any one of claims 1 to 6, wherein the fiber sheet has a permeability of 1.6 or more .
However, the transmittance of the fiber sheet is measured using a spectrophotometer in the wavelength region of 360 to 830 nm, and the integral value T1 of the transmittance in the wavelength region is obtained from the obtained transmittance curve, and the integral of this transmittance is obtained. From the value T1 and the density M of the fiber sheet, the non-permeability per unit density ((100−T1) / M) is calculated and defined as the permeation resistance.