JP2003166160A - High-rigidity nonwoven fabric, curtain core and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a high-rigidity nonwoven fabric which has high rigidity at a high temperature regardless of thinness, uniform formation and is suitable for various kinds of core materials and reinforcing support and to provide a method for producing the same. <P>SOLUTION: This high-rigidity nonwoven fabric is a short fiber nonwoven fabric which comprises a short fiber A having <25 μm fiber diameter and a short fiber B having 25-45 μm fiber diameter. The nonwoven fabric in an amount 50-100 mass % is a heat bondable conjugate fiber having a low-melting component with 160-230°C melting point. Preferably tenacity in the lateral direction of the nonwoven fabric is ≥1.3 times tenacity in the longitudinal direction. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a highly rigid nonwoven fabric. More specifically, the present invention relates to a high-rigidity nonwoven fabric which has high rigidity at high temperature and has a uniform texture even though it is thin, and which is suitable for various core materials and reinforcing supports, and a method for producing the same. The present invention also relates to a curtain core obtained by slitting the nonwoven fabric.

[0002]

2. Description of the Related Art Conventionally, a non-woven fabric having a high rigidity has been used as a reinforcing material such as a curtain interlining material or a filter support. However, it was effective to increase the fiber diameter as a means for producing a nonwoven fabric with high rigidity, but the problem that the texture is not good because the number of constituent fibers decreases with the same nonwoven fabric weight when the fiber diameter is large. was there. Further, there is a problem in that the non-woven fabric whose rigidity is increased by using a binder is difficult to recycle due to the presence of the binder resin and has a large environmental load. Further, the conventionally used nonwoven fabric has a problem that the shape stability is poor in a high temperature atmosphere of 60 ° C. or higher and the rigidity is apt to decrease.

Monofilament woven fabrics and resin-processed non-woven fabrics have been commonly used in curtain core applications.
Further, the curtain core is often used by slitting it in the longitudinal direction, and it has been said that it is preferable to increase the rigidity in the transverse direction, which is a direction orthogonal to the longitudinal direction, but there is almost no nonwoven fabric corresponding thereto. Further, since the curtain is cleaned, morphological stability at high temperature is important, but there are not many nonwoven fabrics that can meet the requirement. Recently, it has come to be used for automobile interior related applications.
A non-woven fabric having high dimensional stability at a temperature of ℃ or higher is required, and a heat-bonding fiber having a high melting point has been developed. These fibers are
For example, it has been used for manufacturing non-woven fabrics having a relatively high basis weight, and has been used for automobile ceiling materials and the like.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a high-rigidity non-woven fabric which has high rigidity at high temperature and uniform texture even though it is thin, and is suitable for various core materials and reinforcing supports, and its production. The purpose is to provide a method. Moreover, it aims at providing the nonwoven fabric suitable for the curtain core which slit-processed this nonwoven fabric.

[0005]

The present invention takes the following means in order to solve such a problem. The first invention is a short fiber A having a fiber diameter of less than 25 microns and a fiber diameter of 25 to 45.
A short fiber non-woven fabric containing at least micron short fibers B, wherein 50-100% by mass of the non-woven fabric has a melting point of 160-
A high-rigidity nonwoven fabric characterized by being a thermo-adhesive conjugate fiber having a low melting point component of 230 ° C.

The second invention is that the lateral strength of the nonwoven fabric is
The high-rigidity nonwoven fabric according to the first aspect is characterized in that it has a strength of 1.3 times or more in the longitudinal direction.

In a third aspect of the invention, the unit weight of the non-woven fabric is 60.
-150 g / m < ² >, thickness is 0.3-0.9 mm, It is a high rigidity nonwoven fabric as described in 1 or 2 characterized by the above-mentioned.

A fourth aspect of the present invention is a curtain core, wherein the nonwoven fabric of any one of the first to third aspects is cut into a width of 40 to 150 mm for use.

A fifth aspect of the present invention is a method for producing a short fiber non-woven fabric according to any one of the first to fourth aspects, in which a card web obtained by mixing short fibers A and short fibers B into a web by a carding method is used as a cross layer. Alternatively, it is a method for producing a high-rigidity non-woven fabric, which is obtained by laminating a non-woven fabric sheet by a cross wrapper so that the fibers are mainly arranged in the lateral direction, and then integrating them by an air-through method.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.
The non-woven fabric used in the present invention includes a short fiber A having a fiber diameter of less than 25 microns and a short fiber B having a fiber diameter of 25 to 45 microns.
It is necessary that the short-fiber nonwoven fabric contains at least and. Fiber diameter 25-45 microns, preferably 30
High rigidity can be obtained by using thick short fibers B in the range of up to 45 microns. On the other hand, it is possible to improve the texture by using the short fibers A having a fiber diameter of less than 25 microns, preferably around 22 microns. It was confirmed by experiments that the ratio of the fiber diameters of the short fibers A and the short fibers B should be 1.2 or more, preferably 1.5 or more, and particularly preferably 1.7 or more in order to obtain a proper mixing effect. Was done.

Next, the nonwoven fabric of the present invention needs to be a heat-adhesive conjugate fiber having a low melting point component having a melting point of 160 to 220 ° C. of 50 to 100% by mass. The heat-sealing fibers may be short fibers A, short fibers B, or both. Also, a third component containing the heat-adhesive fiber may be present. The content of the heat-adhesive conjugate fiber needs to be 50 to 100% by mass, preferably 70% by mass or more, and particularly preferably 90% by mass or more. When the content of the heat-sealing fiber is low, it becomes difficult to obtain the high rigidity which is the object of the present invention. In the range of studies by the inventor, the larger the amount of the heat-adhesive component, the more preferable the direction because the fraying due to the fraying of the non-woven fabric due to cutting and abrasion is suppressed.

The melting point of the low melting point component of the heat fusion fiber is 160-
It is 230 ° C, and preferably 190 to 230 ° C. If the melting point is low, it becomes difficult to increase the rigidity at high temperature. Further, if the melting point is higher than 230 ° C., the temperature difference with the high melting point component is small, so that a long time heat treatment is required, and a thin non-woven fabric is easily subjected to thermal deterioration during processing, causing a problem in durability, and reducing productivity. There may be a problem that it is difficult to raise the price. Although it depends on the processing method of the nonwoven fabric, generally, the higher the melting point of the heat-sealing fiber, the higher the dimensional stability at high temperature, and the smaller the shrinkage upon washing when used as a curtain, which is preferable. The heat-adhesive fiber may be a core-sheath type fiber, a side-by-side type fiber, or a split fiber type fiber without any particular problem.

Further, in the nonwoven fabric of the present invention, the strength of the nonwoven fabric sheet in the transverse direction is preferably 1.3 times or more, and particularly preferably 1.4 times or more and 2 times or less than the longitudinal strength. The nonwoven fabric of the present invention preferably has higher rigidity in the lateral direction than in the longitudinal direction when it is used for a support or a curtain core. This is because the sheet is pleated so as to have a fold line in a direction perpendicular to the longitudinal direction of the sheet, so the distance between the fold lines in that direction is not so large, and rather the strength is relatively low in order to make the fold line easier. Is considered to be preferable. On the other hand, in order to use it as a filter support or a curtain core, it is more preferable that the lateral rigidity is high. The strength ratio can be set in an appropriate range by controlling the fiber arrangement during the production of the nonwoven fabric. When used as a curtain core, it is difficult to perform sampling and measurement because it is used with a narrow width, and therefore it is preferable to manage by substituting thickness and strength.

It is preferable that the basis weight of the nonwoven fabric is between 60 and 150 g / m ² and the thickness is between 0.3 and 0.9 mm. When the basis weight is less than 60 g / m ² , the high rigidity targeted by the present invention cannot be expected so much. On the other hand, when the basis weight exceeds 150 g / m ² , the nonwoven fabric becomes too thick, and when it becomes too thin, it becomes too stiff or becomes a film, which causes a problem that the composite filter material and the curtain outer material are damaged. There is a case. Even if the basis weight is set too large, the curtain and filter may become too heavy or too stiff, which makes the workability such as sewing workability, pleating workability, and needle passing property of the sewing machine convenient and convenient for use. There is a tendency that the sex is not good. If the thickness of the non-woven fabric is less than 0.3 mm, it becomes difficult to obtain the high rigidity that is the object of the present invention, and the cut surface becomes an acute angle, which may hurt the surface of the curtain or the hand of the operator. Further, if the thickness is more than 0.9 mm, the filter tends to be bulky and the curtain core may have a poor texture.

The bending resistance of the non-woven fabric is JIS L 1
It is preferably 100 mgf or more, more preferably 130 mgf or more, as measured by the 085 B method (Gurley method).

The material constituting the nonwoven fabric of the present invention is not particularly limited, but a polyester material is preferable because it is easy to recycle and has excellent heat resistance. Polyester is also excellent in achieving the object of the present invention in that it is unlikely to undergo discoloration or deterioration during use. Further, when used as a curtain core, polyester or nylon is particularly preferable from the viewpoint of compatibility with the outer material. On the other hand, there is no problem in mixing fibers made of a plurality of materials. Within the scope of the study by the present inventors, it was particularly effective to use the core-sheath type polyester fiber in order to obtain high rigidity. It is particularly preferable that the low melting point component of the sheath component is a copolyester having a melting point of about 190 to 210 ° C. and the core component is polyethylene terephthalate. When the heat-adhesive fiber having a relatively high melting point is used, it is easy to prevent wrinkles and shrinkage during washing when used as a curtain core.

In the production of the present invention, short fibers A and short fibers B are mixed and then webbed by a carding method. The card web is laminated by a cross layer, a cross wrapper, or the like, and then hot air is passed through the nonwoven fabric by the air-through method to be heat-sealed. By laminating with a cross layer or a cross wrapper, the fibers in the non-woven fabric can be arranged more laterally. At this time, it is necessary to set the melting point and the bonding condition of the heat-bondable fiber within an appropriate range so that the non-bonding fiber does not cause a problem such as shrinkage due to heat. It is possible to control the fiber arrangement and the shrinkage of the non-woven fabric by sandwiching the web with a net during heat treatment or restraining the ends with a pin tenter.

Further, it is possible to control the fiber arrangement of the non-woven fabric by applying an appropriate overfeed in consideration of shrinkage during heat treatment to some extent. For the purpose of further increasing the adhesive strength obtained by the air-through method, it is preferable to perform a press treatment in a subsequent step. Preferably, it is possible to increase the adhesive strength and the rigidity by passing between plain rolls having a smooth surface and pressing at a temperature of about 120 to 200 ° C. In particular,
For curtain core applications, it is preferable because the surface is smooth and the thickness is uniform.

When used as a curtain core, the nonwoven fabric of the present invention can be cut into a width of 40 to 150 mm and used. It is also possible to use it by punching it out as a tassel core.

[0020]

EXAMPLES The present invention will be described below with reference to examples. The evaluation used the following method. (Average fiber diameter) A scanning electron micrograph was taken at an appropriate magnification, 20 or more fiber side surfaces were measured, and the average value was measured. When the ultrafine fiber non-woven fabric is produced by the melt blow method, the variation in fiber diameter is large, so 100 or more fibers were measured and the average value was adopted.

A non-woven fabric (with a basis weight) was cut into a piece of 20 cm square, and its mass was measured to convert it to a basis weight per 1 m ² .

(Thickness) A non-woven fabric was measured evenly per 1 m width at 5 locations under a load of 50 g / cm ² , and the average value was adopted.

(Tensile Strength and Elongation) A non-woven fabric having a length of 20
It was cut out into a rectangle with a width of 5 cm. At 25 ° C. at room temperature, the maximum strength and elongation at break were obtained when the low-speed elongation tensile measurement was carried out with a test length of 10 cm and a crosshead of 20 cm / min.

(Shrinkage rate) The nonwoven fabric was cut into rectangles each having a length of 30 cm. The nonwoven fabric was heat-treated in an oven at 160 ° C. for 15 minutes, the shrinkage ratio of length and width directions was measured, and the average value was adopted.

Example 1 Fibers having an average fiber diameter of about 20 microns and about 34 microns (trade name: Melty 208, manufactured by Nippon Ester Co., Ltd.
(0, core component melting point: about 255 ° C., sheath component: about 200 ° C.) were mixed in a weight ratio of 3: 2, and then a nonwoven fabric having a basis weight of 90 g / m ² was prepared by carding treatment and a cross wrapper. Next, after thermally bonding the fibers by the air-through method, press processing with a plain calender,
The thickness was adjusted to 0.45 mm. The characteristics of the nonwoven fabric (longitudinal and transverse tensile strength and elongation, heat shrinkage) are shown in Table 1. The obtained non-woven fabric was cut into a width of 7.5 cm to obtain a curtain core. When processed at a sewing factory, it was possible to finish the edges with good workability.

Comparative Example 1 Fibers having an average fiber diameter of about 20 microns manufactured by Nippon Ester Co., Ltd. (trade name: Melty 2080, core component melting point about 25)
(5 ° C., sheath component about 200 ° C.) was opened, and then a carding treatment and a cross wrapper were used to prepare a nonwoven fabric having a basis weight of 90 g / m ² . Subsequently, the fibers were heat-bonded by the air-through method, and then pressed with a plain calender to adjust the thickness to 0.25 mm. The characteristics of the nonwoven fabric (longitudinal and transverse tensile strength and elongation, heat shrinkage) are shown in Table 1. Although the obtained non-woven fabric had a good texture, it had a problem of low rigidity. The nonwoven fabric was cut into a width of 7.5 cm to form a curtain core, but the pleats processed at the sewing factory had a weak waist and could not be finished neatly.

Comparative Example 2 Fiber manufactured by Nippon Ester Co., Ltd. having an average fiber diameter of about 34 microns (trade name: Melty 2080, melting point of core component of about 25)
(5 ° C., sheath component about 200 ° C.) was opened, and then a carding treatment and a cross wrapper were used to prepare a nonwoven fabric having a basis weight of 90 g / m ² . Subsequently, the fibers were heat-bonded by the air-through method, and then pressed with a plain calender to adjust the thickness to 0.45 mm. The characteristics of the nonwoven fabric (longitudinal and transverse tensile strength and elongation, heat shrinkage) are shown in Table 1. The resulting non-woven fabric texture was poor and was a problem. The non-woven fabric was cut into 7.5 cm width to make a curtain core,
When it was processed at a sewing factory, it did not follow the outer material well and wrinkled, so it could not be finished neatly.

The results of Examples and Comparative Examples are summarized in Table 1.

[Table 1]

[0029]

INDUSTRIAL APPLICABILITY The non-woven fabric obtained by the present invention is suitable for various core materials and reinforcing supports because it has high rigidity at high temperature and uniform texture even though it is thin. In particular, when the nonwoven fabric is subjected to slit treatment, it is preferably used as a curtain core.

Continued front page    F-term (reference) 2E182 CC09                 4L047 AA27 AA28 AB02 AB07 BA08                       BA23 CA19 CB01 CB10 CC10                       CC16 EA10

Claims (5)

[Claims] 1. A short fiber non-woven fabric containing a short fiber A having a fiber diameter of less than 25 microns and a short fiber B having a fiber diameter of 25 to 45 microns, wherein 50 to 100% by mass of the non-woven fabric has a melting point of 160 to 230. A high-rigidity non-woven fabric, which is a thermo-adhesive conjugate fiber having a low melting point component of ℃. 2. The high-rigidity nonwoven fabric according to claim 1, wherein the strength of the nonwoven fabric in the transverse direction is 1.3 times or more the strength in the longitudinal direction. 3. The basis weight of the non-woven fabric is 60 to 150 g / m.
^2. The high-rigidity nonwoven fabric according to claim 1 or 2, having a thickness of 0.3 to 0.9 mm. 4. The nonwoven fabric according to any one of claims 1 to 40
A curtain core that is used by cutting it to a width of 150 mm. 5. A method for producing a short-fiber non-woven fabric according to any one of claims 1 to 4, wherein a short-fiber A and a short-fiber B are mixed and a card web made by a carding method is used as a cross layer or cloth. A method for producing a high-rigidity non-woven fabric, which comprises stacking the non-woven fabric sheets by a wrapper so that the fibers are mainly arranged in the lateral direction and then integrating them by an air-through method.