JP3134963B2 - Leather-like staple fiber non-woven fabric - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leather-like short-fiber nonwoven fabric excellent in moldability and abrasion resistance while maintaining the soft and warm feel of the nonwoven fabric. The present invention relates to a leather-like short-fiber non-woven fabric that can be used as a surface covering material as an interior part of a vehicle, such as an automobile or a train, and the like.

[0002]

2. Description of the Related Art In recent years, in automobile interior materials,
He hated PVC leather and began to use a lot of textiles. The reason is the leather-like appearance of PVC leather,
Because of its low cost, good wear resistance, good moldability, etc., it is used in ceiling skin materials, door trims, instrument panels, etc. of mass passenger cars. On the other hand, textiles are preferred for warm texture and natural appearance, but in the above-mentioned applications, except for the ceiling skin material, the fabric does not reach the price performance of the PVC leather and some fabrics are used in the ornament part of the door trim. It is only being done. Further, the conventional nonwoven fabric has good moldability, but has a drawback that the pattern is poorly changed and fluffing occurs due to long-term use, and the appearance is significantly impaired. Therefore, they are hardly used in the above-mentioned applications. A short-fiber nonwoven fabric which is impregnated with a thermoplastic resin to the surface or inside and then pressure-bonded by hot embossing, has fluff on the surface and does not have a leather-like appearance, but also has poor abrasion resistance.

[0003]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned conventional problems and maintains a soft and warm touch feeling, and has no fuzz on the surface and is a low-priced leather tone excellent in moldability and wear resistance. Short fiber nonwoven fabrics are to be provided.

[0004]

The present invention adopts the following means in order to solve such a problem. That is,
The present invention relates to a short-fiber nonwoven fabric in which a surface layer portion and an inner layer portion are three-dimensionally entangled and integrated, and a thermoplastic resin adhered by 5 to 40% by weight of the weight of the short-fiber nonwoven fabric. The surface layer portion is made of a fine continuous leather-like pattern, the concave portion of the cross section of the nonwoven fabric is a fiber layer in which constituent fibers are bonded together at a high density by the thermoplastic resin, and the convex portion of the cross section is A fiber layer in which the constituent fibers are bonded to each other at a low density by the thermoplastic resin, and the ratio of the average depth A of the concave portion of the cross section of the nonwoven fabric to the average thickness B of the nonwoven fabric satisfies the following expression; there is fluff on the surface of the surface layer portion
And the stress (ST40) at 40% elongation of the nonwoven fabric
It is a leather-like short-fiber nonwoven fabric characterized by being 5 kg / 5 cm to 25 kg / 5 cm . 0.12 ≦ A / B ≦ 0.55 (1)

[0005] Further, the present invention provides the above-mentioned non-woven leather nonwoven fabric comprising a non-woven nonwoven fabric entangled by needle punching or hydroentanglement, wherein the non-woven non-woven leather fabric has a thickness of 0.5 mm to 5.0 mm. 80g / m ² 〜 30
Is 0 g / m ² is a leather-like short fiber non-woven fabric of claim 1.

Hereinafter, the present invention will be described in detail. In the present invention, the short-fiber non-woven fabric is obtained by forming cellulose-based fibers such as rayon acetate, synthetic fibers such as polyester and polyamide into a web and needle-punching or hydro-entangled them to be three-dimensionally entangled and integrated. .
The fiber length of the short fibers is 10 mm or more, preferably 30 mm or more and 50 mm or less.

As the thermoplastic resin impregnated in the short-fiber nonwoven fabric, polyvinyl acetate, polyethylene, polyacrylate and the like are preferably mentioned. In addition, a plasticizer, a softener, and the like, a flame retardant, and a pigment may be mixed with these resins.

[0008] The thermoplastic resin is 5 to 4 weight of the total weight of the nonwoven fabric.
0% by weight, preferably 10 to 30% by weight. Here, if the amount of the thermoplastic resin is less than 5% by weight, the constituent fibers cannot be bonded to each other, so that fluff is present on the surface of the surface layer portion, which causes a reduction in wear resistance. On the other hand, if the content exceeds 40% by weight, the softness of the nonwoven fabric is reduced, resulting in a plastic feeling.

In the present invention, the thermoplastic resin is impregnated with
The process is performed uniformly from the surface of the short-fiber nonwoven fabric. At least 2% of the total thickness of the short-fiber nonwoven fabric is bonded to each other by a thermoplastic resin.

When the thermoplastic resin is impregnated up to 100% of the total thickness of the short-fiber nonwoven fabric, the dipping method may be used. However, when the resin is impregnated from 2% to less than 100% of the total thickness, coating is performed. The method is preferred. If the resin layer is less than 2% from the surface, the constituent fibers cannot be adhered to each other by hot embossing, so that fluffs are present on the surface, causing a problem that the abrasion resistance is reduced and the leather does not look like leather. Further, if the resin layer exceeds 60%, the soft feeling of the nonwoven fabric is reduced, and the nonwoven fabric becomes a plastic feeling. Therefore, the resin layer is preferably 5% or more and less than 50% of the total thickness from the nonwoven fabric surface.

The convex portion of the non-woven fabric has a low adhesion density of the constituent fibers, and the concave portion has a high adhesion density of the constituent fibers. The ratio of the cross section of the nonwoven fabric with leather to the average thickness B is in the range of 0.12 ≦ A / B ≦ 0.55, preferably in the range of 0.18 ≦ A / B ≦ 0.55. . In addition,
The depth A and average thickness B of the concave portion are measured by a digital thickness gauge (micron measuring device) by reading the maximum, minimum, and average values from a waveform obtained by a surface roughness meter (micron measuring device). Is obtained by When A / B is less than 0.12, the leather-like pattern becomes inconspicuous and the leather-like pattern is elongated during molding, and the leather-like short-fiber nonwoven fabric of the present invention is not obtained. On the other hand, when A / B exceeds 0.55, the uniformity of the appearance of the leather-like surface is deteriorated, which is not preferable. Preferably 0.18 ≦ A /
B ≦ 0.50.

[0012] The non-woven fabric of short-fiber leather according to the present invention comprises a non-woven fabric of short fibers which is entangled by needle punching or hydroentanglement. It is preferably 5.0 mm. When the thickness is less than 0.5 mm, it is difficult to form a resin layer, and the amount of resin is extremely small, so that the surface becomes fuzzy. On the other hand, if it exceeds 5.0 mm, not only the cost is increased but also the workability during embossing is inferior, which is not preferable. The thickness is measured with a digital thickness gauge at intervals of 20 cm with respect to the entire width. However, the size of the presser foot is 9 mm or more in diameter, the load is 100 g / cm ^2, and the presser foot is allowed to stand for an appropriate time (usually about 10 seconds) until the thickness is settled.
Also, the basis ^{weight, 80g / m 2 ~300g / m} 2 is preferred. When the basis weight is less than 80 g / m ^2, the tensile strength of the base fabric is reduced, and the fabric cannot be used for interior materials such as automobiles. On the other hand, if it exceeds 300 g / m ² , it leads to an increase in cost and is inferior in workability at the time of embossing. The basis weight (g / m ² ) is obtained by measuring one sample per 1 m width with a sample having a size of 1 m × 1 m and allowing water to reach a water equilibrium.

The stress at 40% elongation (ST40) is
5kg / 5cm~25kg / 5cm range near the is, it is preferable that further 7kg / 5cm~20kg / 5cm. When ST40 is less than 5 kg / 5 cm, the leather-like short-fiber nonwoven fabric is partially stretched at the deeply drawn portion during molding, and the leather-like pattern at the deeply drawn portion becomes inconspicuous. ST4
When 0 exceeds 25 kg / 5 cm, wrinkles are formed in the base fabric during molding of the nonwoven fabric of leather-like staple fibers, and the appearance is unpreferably deteriorated. The stress at 40% elongation refers to the stress at 40% elongation in the measurement of the strength and elongation of the leather-like short-fiber nonwoven fabric. Specifically, the sample size is 5 cm.
× 20cm per 1m width, take 3 pieces each for vertical and horizontal, JI
According to SL-1096, it was measured using a constant speed elongation type tensile tester at a gripping interval of 10 cm and a pulling speed of 20 + 2 cm / min.

Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a cross-sectional view of a non-woven leather-like short-fiber nonwoven fabric according to the present invention, wherein 1 indicates a surface layer, and 2 indicates an inner layer. FIG. 2 is a perspective view of the leather-like short-fiber nonwoven fabric. FIG. 3 is an enlarged cross-sectional view of the non-woven leather-like short-fiber nonwoven fabric, where B is the average thickness, and A is the depth of the recess. FIG. 4 is an enlarged sectional view of an embossing roll pair used in the present invention. Reference numeral 3 denotes a steel roll engraved with a leather-like pattern, and reference numeral 4 denotes a paper roll in which the leather-like pattern has the opposite irregularities and is completely fitted in pairs. The paper roll 4 is made by stamping the handle of the steel roll 3 onto the paper over time, and both are completely fitted. With such an embossing roll,
The pressure is easy to apply evenly to the entire surface as well as the convex part of the steel, and the whole surface of the nonwoven fabric is bound by the thermoplastic resin,
They will not have fluff. However, if the unevenness is too deep as described above, the convex portion of the steel roll 3 (FIG. 3)
Pressure is excessively applied, and conversely, the pressure on the concave portion (the convex portion of the non-woven fabric) of the roll is reduced, so that the binding of the fibers by the thermoplastic resin becomes insufficient, and the uniformity of the appearance is deteriorated.
The temperature of the embossing roll is preferably higher, but is preferably higher than the softening point of the thermoplastic resin. In order to further improve the abrasion resistance, it is also possible to incorporate a low melting point fiber up to 10% by weight. If the content is more than 10% by weight, it is not preferable because the color matching becomes difficult, the moldability is lowered, and the fusion of the low-melting fiber becomes glossy and the leather-like appearance becomes poor in uniformity.

FIG. 5 is an enlarged cross-sectional view of a commonly used embossing roll pair. Reference numeral 5 denotes a general engraved roll, and reference numeral 6 denotes a flat roll. A feature of the present invention is that it does not have fluff on the surface irrespective of the fact that it is made of a short fiber non-woven fabric, so that a leather-like appearance like PVC leather can be obtained due to such an appearance. Therefore, the effect of the present invention cannot be obtained by embossing for obtaining a leather-like pattern, such as a flat steel roll paired with an embossed steel roll which is a pattern used in a normal nonwoven fabric as shown in FIG.
In other words, in the concave portion (compression-bonded portion) of the non-woven fabric, the fibers are sufficiently bound by the thermoplastic resin and have no fluff, but the convex portion of the non-woven fabric has insufficient pressure. Insufficient binding leaves fluff and leaves no leather-like appearance, but also lowers abrasion resistance.

[0016]

【Example】

Example 1 Using a 3d × 51 mm cut regular polyester fiber, a web of 180 g / m ² was prepared, and then three-dimensionally entangled with a needle punch to form a nonwoven fabric of 150 g / m ^2. To 40 g / m ²
It was applied, impregnated, dried and pressed at 175 ° C. with a hot emboss having a leather-like pattern paired with a paper roll to produce a leather-like short-fiber nonwoven fabric. As shown in Table 1, the physical properties of this product were not only excellent in physical properties but also good in texture and appearance.

Example 2 A web was obtained in the same manner as in Example 1, and a resin was applied and impregnated. Thereafter, the entire surface of the resin-processed surface was overprinted like a finish coat in order to improve the appearance and color matching, and then embossed under the same conditions as in Example 1 to produce a non-woven fabric with leather-like staple fibers. Table 1 shows the physical properties of this product.
It was shown to. As compared with Example 1, the difference was in the physical properties, but the appearance was further improved.

Example 3 A web was obtained in the same manner as in Example 1, and the resin was impregnated by impregnation. Thereafter, the resin-processed surface was entirely overprinted like a finish coat in the same manner as in Example 2, and embossed under the same conditions as in Example 1 to produce a non-woven fabric with leather-like short fibers. A short-fiber leather nonwoven fabric having no difference in physical properties and appearance as compared with Examples 1 and 2 was obtained.

Comparative Example 1 A web was obtained in the same manner as in Example 1, and a resin was dipped and impregnated. Then, it was pressed at 175 ° C. with a hot emboss having a leather-like pattern paired with a paper roll different from that of Example 1 to produce a leather-like short-fiber nonwoven fabric. Table 1 shows the results of measuring the depth A of the concave portion of the product and the total thickness B of the nonwoven fabric. Although there was no particular difference in physical properties, A /
Since B was small, the uneven pattern disappeared at the time of molding, and a leather-like appearance was not obtained.

Comparative Example 2 A web was obtained in the same manner as in Example 1, and a resin was dipped and impregnated. Then, it was press-bonded at 175 ° C. with a hot emboss having a leather-like pattern paired with a paper roll different from that of Example 1 and Comparative Example 1 to produce a leather-like short-fiber nonwoven fabric.
Table 1 shows the results of measuring the depth A of the concave portion of the product and the total thickness B of the nonwoven fabric. Although there was no particular difference in physical properties, the unevenness was remarkable due to the large A / B, and the appearance was glaring, and the appearance became plastic-like. The result was a decrease.

[0021]

[Table 1]

The characteristics in the table were determined in the following manner. ○ Abrasion resistance: Wear wheel (NO. CS-10), load 250g, using Taber tester according to JIS L-1096.
Based on 500 classifications. ○ Appearance: Compare and judge the degree of leather-like appearance visually 5th grade: Good leather-like pattern with good uniformity and no fuzz on the surface 4th grade: Good leather-like pattern, slightly good uniformity and good surface No fluff 3rd grade: leather pattern is poor in uniformity or fuzz is observed on the surface 2nd grade: leathery pattern is easily broken and has shallow or fuzzy 1st grade: leathery pattern is unclear Or a lot of fluff ○ Texture: Tactile feeling and softness are compared as follows Class 5: Most soft Class 4: Soft Class 3: Hard Class 2: Hard and rough Class 1: Plastic-like Judging from the required characteristics, it is not a factor as important as the appearance and the abrasion resistance. ○ Comprehensive evaluation: Comparative evaluation with a little weighting of the above three items A: Best (pass) B: Good (pass) C: Normal (pass) D: Bad (fail) E: Worst (fail)

[0023]

According to the present invention, the following excellent effects can be obtained. 1) A short-fiber leather nonwoven fabric excellent in abrasion resistance, appearance and texture can be obtained. 2) Since it has the inherent extensibility of a nonwoven fabric, it is excellent in moldability, and the leather-like pattern does not disappear even when hot press molding or cold press molding is performed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a leather-like short-fiber nonwoven fabric of the present invention.

FIG. 2 is a perspective view of a leather-like short-fiber nonwoven fabric of the present invention.

FIG. 3 is an enlarged cross-sectional view of a leather-like short-fiber nonwoven fabric of the present invention.

FIG. 4 is a partial sectional view of a pair of rolls used in the present invention.

FIG. 5 is a partial sectional view of a pair of conventional rolls for embossing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Surface part 2 Interior part 3 Leather-like steel roll 4 Leather-like paper roll 5 Conventional embossing roll 6 Flat roll A Depth of the concave part of the surface part of leather-like staple nonwoven fabric B Average thickness of leather-like staple nonwoven fabric

Claims (2)

(57) [Claims] 1. A short fiber nonwoven fabric in which a surface layer portion and an inner layer portion are three-dimensionally entangled and integrated, and a thermoplastic resin adhering to 5 to 40% by weight of the weight of the short fiber nonwoven fabric. Is compressed, the surface layer portion is formed of a fine continuous pattern of leather tone, the concave portion of the cross section of the nonwoven fabric is a fiber layer in which constituent fibers are bonded together at a high density by the thermoplastic resin, and the convex portion of the cross section. Is a fiber layer in which the constituent fibers are adhered to each other at a low density by the thermoplastic resin, and the ratio of the average depth A of the concave portions of the cross section of the nonwoven fabric to the average thickness B of the nonwoven fabric satisfies the following expression; Fluff present on the surface of the surface layer
No, and stress at 40% elongation of the nonwoven fabric (ST40)
Is 5 kg / 5 cm to 25 kg / 5 cm . 0.12 ≦ A / B ≦ 0.55 (1) 2. The nonwoven fabric of leather-like staple fibers is a nonwoven fabric of short fibers entangled by needle punching or hydroentanglement, and the nonwoven fabric of leather-like staple fibers has a thickness of 0.5 mm to 5.0.
^{2. The} nonwoven fabric made of leather according to claim 1, wherein the basis weight is 80 g / m ^{2 to} 300 g / m ² .