JPS63165559A - Molding cloth - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a molding fabric for automobile interiors, etc., which has a three-dimensionally complicated curved surface. There are few.

The present invention also relates to a molding fabric with good appearance quality.

(Prior Art) Conventionally, a method for thermoforming fabrics such as woven or knitted fabrics into a curved shape such as a hat is disclosed in Japanese Patent Application Laid-open No. 15698/1983.
Further, a method of thermoforming to conform to the irregularities of automobiles and buildings is known from Japanese Patent Publication No. 1811/1983. That is, the former has a birefringence (△n
) is 0.02-0.10 by using a fabric such as a woven or knitted fabric made of undrawn polyester yarn, it is possible to avoid applying unreasonable stress to the woven or knitted fabric even in the mountain portions where maximum deformation occurs during thermoforming. In addition, highly oriented undrawn polyester yarn with a birefringence index (△n) of 0.02 to 0.08 is arranged in the ground part, and the softening point is higher than that of the fiber. It is disclosed that thermoforming into a three-dimensional shape is possible by using a moldable fiber sheet in which fibers having the above properties are arranged in a pile portion.

(Problems to be Solved by the Invention) However, in any molding sheet, when the yarn is made of polyester, the birefringence (An) is 0.02 to 0.
Since it uses an undrawn yarn of 1O, it has the following disadvantages.

That is, in the case of a highly oriented undrawn yarn with a birefringence index (An) of 0.065 or more, the initial elastic modulus is higher than that of a low oriented undrawn yarn, so there is less deformation due to force, and the molecular orientation is high, so there is no noticeable necking. However, in the case of such highly oriented undrawn yarns, crystallization is progressing along with single-molecule orientation, so the heat shrinkage rate of the yarn is small, and fabric manufacturing is difficult. Since the amount of shrinkage of the yarn is small even after the subsequent heat treatment, there is a drawback that when thermoforming is performed by vacuum forming, there is little room for the yarn to stretch, making it difficult to obtain a molded product that conforms to the irregularities of a complicated curved surface.

In order to solve these problems, the present inventors previously proposed Japanese Patent Application No. 61-203270 as a base fabric for reinforcing molding. This base fabric for reinforcing molding is a single knitted fabric composed of low-oriented polyester drawn yarn, and has a good lift rate by limiting the average yarn feeding length of one loop of the knitted fabric to a specific range. It has high extensibility. However, since the first stitch structure is plain and loose,
During thermoforming, elongation becomes uneven at each uneven portion, uneven pile density is observed after thermoforming, and the appearance quality is poor.

(Means for Solving the Problems) The present inventors have discovered that it is possible to easily ripen three-dimensional shaped objects having various curved surfaces, and that it is possible to easily ripen three-dimensional objects having various curved surfaces, and that it is possible to easily ripen a three-dimensional object having various curved surfaces. The present invention was achieved as a result of extensive research in order to obtain a forming fabric that is easy to manufacture, has fewer defects after knitting, and has a good pile appearance after forming.

That is, the present invention is a polyester yarn whose main repeating unit is an ethylene terephthalate unit, which has an average birefringence (An) of more than 0.08 and less than 0.15, and an average density of 1.365 g/cn! A single made of a low oriented drawn yarn as shown below arranged in the ground part and a highly oriented drawn thread having a single filament fineness of 0.1 denier or more and 3 denier or less and which has a higher orientation than the low oriented drawn thread in the pile part. It is a pile knitted fabric, and the gist thereof is a fabric for forming, in which the pile portion of the knitted fabric is subjected to napping and shearing treatment.

The polyester yarn whose main repeating unit is an ethylene terephthalate unit used in the present invention is polyethylene terephthalate or a copolymerized polyester yarn mainly composed of ethylene terephthalate units. As the copolymerization component, conventionally known acid components and glycol components can be used, and the acid components include isophthalic acid, 5-sodium sulfoisophthalic acid, adipic acid, and cepatic acid, and the glycol components include propylene glycol, butylene glycol, diethylene glycol, neoplastic acid, etc. Pentyl glycol and the like are used. In addition, from the standpoint of stability over time and thermal stability of polyester, the ethylene terephthalate component is
Polyester containing 5 mol% or more is preferred.

Second, the yarn quality of the yarn constituting the ground portion of the molding fabric of the present invention is such that the average birefringence (△n) is greater than 0.08 and 0.15 or less, and the average density is 1.365 g. /
c + d or less, and in order to obtain this yarn, for example, if the natural draw ratio of a highly oriented undrawn yarn with a birefringence (An) of 0.03-0.065 is X, then It is obtained by cold-stretching the drawn yarn at a draw ratio of X to 1.2X.

Here, the birefringence index (An) is widely used as a measure of the orientation of nine molecular chains, and is measured using a polarizing microscope.
It is determined by measuring the retardation value under a monochromatic light source with a constant wavelength.

The average birefringence (S) is determined by continuously measuring the low oriented drawn yarn in the length direction, calculating the average value of An for the unstretched portion and the stretched portion. The average length ratio between the two is calculated from the cross-sectional area, and is obtained from equation (1).

-1 (An m ×L a+△nbXLb)
(1) However, S1°: average birefringence △nii birefringence △n of the stretched part, ; birefringence of the unstretched part L a i length fraction (%) of the stretched part L, ; unstretched Length fraction (%) of the part If the average birefringence (Δ lower) of the oriented drawn yarn is set to 0.08 or less, the elongation during thermoforming will be thick (so the formability will improve, but this If the stretching ratio is increased more than necessary, the average birefringence (lower τ) after stretching is undesirable. 0
．． As the yarn becomes larger than 15, the residual elongation of the yarn decreases, and the elongation of the ground part of the single-pile knitted fabric cannot be expected even if napping and shearing are performed before forming, resulting in fabric defects such as peeling. This is not desirable because it stands out. Therefore, the average birefringence (...) of the low-oriented drawn yarn is 0.
It is preferable from the viewpoint of moldability and process operation that the value is greater than 0.08 and less than or equal to 0.15.

Next, it is preferable that the average density of the yarn is 1.365 g/crl or less. The average density of yarn is 1.365
If it is higher than g/era, the 1 heat shrinkage rate becomes small and elongation of the yarn during molding cannot be expected, which is not preferable.

The average density of the yarn was sampled at 50 random points from the yarn to be measured, and was heated to 20°C using a density gradient tube.

This is the average value of 50 measurements for ligroin/carbon tetrachloride system.

That is, since the yarn has been subjected to a drawing process, it has great resistance due to abrasion and bending during the production of knitted fabrics, and the damage to the yarn itself is minimal, unlike highly oriented undrawn yarn. In addition, since the average density of the yarn is less than 1.36587 cut and crystallization has not progressed, the elongation rate and thermal shrinkage rate are high. The amount of shrinkage of the strips increases, and the elongation of the base fabric increases dramatically.

However, if brushing and shearing are not performed, depending on the degree of unevenness of the three-dimensional object, unevenness will be observed in the pile density due to uneven elongation at each uneven part during thermoforming, resulting in poor appearance quality. . In order to improve these problems, it is necessary to cover the surface of the fabric with uniform fluff by napping and shearing treatments.

By arranging the above-mentioned low-oriented drawn yarn in the ground part and using drawn yarn with a higher orientation than the ground part in the pile part, a fabric with stable knitting properties and fewer surface defects caused by dyeing spots etc. can be obtained. . The drawn yarn constituting the pile part can be a highly oriented drawn yarn produced by a known spinning/drawing method, and the materials are polyamide fibers such as nylon 6°, nylon 66, polyethylene, etc., depending on the dyeability and mechanical properties of the yarn. Polyester fibers made of terephthalate and copolymers thereof are preferably used.

The single yarn fineness of highly oriented drawn yarn is 0.1 denier or more 3
It is important that it is no more than denier. If the single yarn fineness exceeds 3 denier, the fluffed part after raising will have a hard texture and rough appearance, lacking a luxurious feel. On the other hand, if the denier is less than o or i, it is difficult to manufacture the yarn and the cost is high, and because the fineness of the single yarn is small in the raising process, the effect of drawing out the fibers by the clothing is small, the fluff density is low, and the fluff length is short. This is not preferable because only a raised fabric can be obtained. The softness of the texture is better when the single yarn fineness is smaller.

Considering the napping properties and workability of the knitted fabric, the single yarn fineness is 0.3.
A denier or higher is particularly preferred.

Next, in order to obtain a molding fabric with a high fluff density after thermoforming, knitting is performed with the yarn feeding length ratio of the pile portion being 1.2 or more and 2.5 or less, compared to the yarn feeding length ratio of 1 in the ground portion. It is preferable. If the pile portion yarn feeding length ratio is less than 1.2, the pile length after raising will be short and the texture will be noticeable, resulting in poor appearance quality. On the other hand, if the yarn feeding length ratio exceeds 2.5, the raised clothing will penetrate deeply, making it difficult to separate the needles and making uniform raising difficult.

It goes without saying that conventionally known napping techniques can be used to obtain a molding fabric with a high fluff density after ripening.

In other words, the napping structure is a loose structure with many floating weft yarns, the addition of a silicone or paraffin softener that gives appropriate flexibility and squeaky feel in order to improve the width of the nap, and the use of hydraulic pressure. Any raising technique may be applied, such as a strong raising method using a type raising machine.

(Function) The present inventors have considered the following as the reason why the molding fabric of the present invention is suitable for molding fabrics such as automobile interiors having three-dimensionally complicated curved surfaces.

First, since the low orientation drawn yarn constituting the ground portion of the single pile knitted fabric is cold drawn, it has a higher initial elastic modulus and is less deformed by external force than undrawn yarn spun at high speed. Also, J! ! ! Since it is durable against over-bending, there are almost no problems such as thread breakage during fabric production.

Next, the pile part uses normally highly oriented hot drawn multifilament yarn with a single yarn fineness of 0.1 denier or more and 3 deniers or less, but the yarn feeding length of the ground part is When the raising and shearing treatment is performed by limiting the yarn feeding length ratio of the pile part to a range of 1.2 or more and 2.5 or less compared to a ratio of 1.

It has an appropriate napping density and can be raised smoothly. Furthermore, the pile part is freed from the ground threads by shearing, so it does not cause large distortion to the fabric during deformation, and the difference between the ground part and the pile part is reduced. The difference in shrinkage characteristics has also been resolved, and no slack is observed when the fabric is hung.

Also, the low orientation drawn yarn used in the ground section.

Due to its low crystallinity, it has a high thermal shrinkage rate, and the yarn shrinks well when heat treated before thermoforming. As mentioned above, the shrinkage force of the gland thread is not constrained by the threads of the pile part, so increasing the shrinkage capacity of the ground thread leads to an increase in the elongation capacity during ripening. This means that it is possible to perform molding that is suitable for objects that have

Therefore, the elongation at break of the molding fabric in the present invention is 180% or more in the longitudinal direction and 230% or more in the transverse direction when measured at room temperature, and 23% or more in the longitudinal direction when measured at 180°C.
It shows a high elongation rate of over 0% and over 250% in the horizontal direction,
The resulting fabric can be easily deformed during thermoforming. Furthermore, unnecessary fuzz is removed by the shearing process, and the length of the fuzz on the surface of the fabric is evened out, so density unevenness in the fabric due to differences in extensibility during thermoforming is less noticeable.

Note that the exact correspondence between omnidirectional deformation during thermoforming and deformation in one axial direction is not understood.

In general, if the elongation at break in the vertical and horizontal directions is well balanced, and the elongation in both directions is high, it is thought that the elongation at break in omnidirectional deformation will be high.

As mentioned above, using low oriented drawn yarn in the ground part,
A single pile knitted fabric using a drawn multifilament yarn having a higher orientation than the low orientation drawn yarn in the pile part, and the knitted fabric is further subjected to napping and shearing treatment,
This is a fabric for molding that has improved the conventional drawbacks, has good appearance quality, and has a soft feel.

(Example) The present invention will be explained below with reference to nine examples. In addition.

The physical properties measured in Examples were evaluated by the methods described below.

(1) Birefringence (△n) Using a POH type polarizing microscope manufactured by Nippon Kogaku Co., Ltd., the sample was placed diagonally and the letter d'rayon value was measured with white light.

The average birefringence (△Ryo-) is determined by continuously measuring the low-oriented drawn yarn 100 times in the length direction at 1 cffl intervals, and calculating the average value of △n for each of the unstretched and stretched parts.
Next, the average length ratio of the unstretched portion and the stretched portion was calculated from the cross-sectional area of the unstretched portion and the stretched portion, and was determined from formula (11) in the specification.

(2) Water conduction shrinkage rate Using an ε meter manufactured by Toyobo Engineering ■, sample length 50 cm, load 0.001 g/d, temperature 98°C
, the treatment time was 5 seconds, and the measurement was performed under the conditions of n=20.

(3) Density Using a ligroin/carbon tetrachloride density gradient tube.

Measured at 20°C.

(4) Elongation rate of yarn ■ Tensilon UTM-4-10 manufactured by Toyo Baldwin
It was determined from the average value of n=10 using Type 0, with a sample length of 20 cm and a tensile rate of 20 cn+/min.

(5) Fabric elongation rate ■Tensilon IITM-4- manufactured by Toyo Ball Dry
100 type, sample length 10 am, tensile speed Loa
m/min.

The elongation rate at room temperature and under heating at 180''C was determined from the average value of n=10 under the condition that the sample width was 3 cm.

Examples 1-6. Comparative Examples 1-2 Polyethylene terephthalate with an intrinsic viscosity of 0.69 was used as the first
A yarn for the ground portion of a single-pile knitted fabric was manufactured under the spinning and drawing conditions shown in the table.

(Brand: 150 denier/48 filament) Table 1 ILI, 1, 1, 1, 1, 1, 1. 'Icself)=i'z8
0°C Next, the above yarn was arranged in the ground part, and polyethylene terephthalate drawn yarn 75 denier/72 filament (single yarn fineness 1.04 denier, elongation rate 27%) was placed in the pile part.
, boiling water shrinkage rate 11%) and 75 denier/250 filament (single yarn fineness 0.30 denier, elongation rate 27%).

Spring water shrinkage rate 11%) was used, the yarn feeding length ratio of the ground part/pile part was changed to 1:1.10 to 1.65, and sinker pile knitting machine manufactured by Fukuhara Seiki ■, type XL-FL2.28 was used.
A single pile knitted fabric was knitted using a gauge and a hook diameter of 30 inches. Subsequently, hair was raised (three times) using a hydraulic hair raising machine under strong raising conditions, and presetting was performed using a tenter at 130° C. for 60 seconds. Next, the hair was sheared using a shearing machine (passed twice), and then dyed using a jet dyeing machine at 130° C. for 30 minutes. Next, 2 tenting treatments (140° C. x 30 seconds), shearing treatment (twice), and finishing treatment (150° C. x 6 seconds) were performed.

The elongation rate of the obtained fabric for molding was measured at room temperature and 180° C. using a Tensilon.

The results are shown in Table 2.

From Table 2, the fabric elongation rate of the fabric for molding in the present invention is 180% or more in the vertical direction and 210% or more in the horizontal direction at room temperature, and 190% or more in the vertical direction at 180°C.

It showed 250% or more in the horizontal direction. On the other hand, when ordinary highly oriented drawn yarn is used in the ground section, at room temperature the vertical direction
0%, horizontal direction 120%, vertical direction 11 at 180°C
It was low at 0% and 140% in the horizontal direction.

Next, the moldability of the obtained fabric for molding was evaluated.

First, polyvinyl chloride resin with the following resin formulation was mixed with 17% and 0% of polyvinyl chloride resin.
After coating with a comma roll coater at 51 liters, vacuum forming was performed at 160° C. using the vacuum forming machine shown in FIG. At this time, the vacuum forming is performed by sandwiching the forming fabric 2 between the hot plate 1 and the mold 4 shown in Fig. 1 and forming it at the above forming temperature, and the position 4 of the fabric after forming is indicated by the dotted line in the figure. As shown, the fabric was deformed along the concave portion of the mold 4. The results are shown in Table 2.

Note that all parts in these two examples indicate parts by weight.

(Resin formulation) Vinyl chloride resin base resin 100 parts (emulsion polymerized product 9 degree of polymerization 1350, particle size 1.2μ, latex concentration 21%) Dioctyl phthalate 40 parts Antimony trioxide 15 As is clear from the phloem, the fabric of the present invention is elongated. Fabrics with a high shearing ratio had good moldability and surface quality, with the pile portions being straightened by the shearing treatment and no ground structure visible. On the other hand, as in Comparative Example 2, the fabric having a yarn feeding length ratio (pile/ground) outside the range of the present invention had a poor quality as the ground texture was visible in the ground portion.

(Effects of the Invention) The present invention has the above-mentioned configuration, and is effective in the steps up to thermoforming, which was a drawback of the conventional method.

Problems such as thread breakage are eliminated, and it can be easily molded without requiring excessive pressure during the thermoforming process.
Even if it is a three-dimensional structure, a laminated fabric with good surface quality can be obtained without internal distortion, and can be widely used in the field of molded products with many uneven parts such as automobile interior parts and buildings.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view of the vacuum forming apparatus. Note that the arrows in Figure 1 indicate the flow of air in a vacuum state. 1------1 heating plate 2---1 fabric for forming 3---1 position of fabric after forming 4--Mold

Claims (2)

[Claims] (1) A polyester yarn whose main repeating unit is an ethylene terephthalate unit, with an average birefringence @(
△n) A low oriented drawn yarn whose @ is greater than 0.08 and 0.15 or less and whose average density is 1.365 g/cm^3 or less is arranged in the ground part, and has a higher orientation than the low oriented drawn yarn. A single pile knitted fabric in which highly oriented drawn yarns having a single yarn fineness of 0.1 denier or more and 3 denier or less are arranged in the pile part, and the pile part of the knitted fabric is subjected to napping and shearing treatment. . (2) Claim 1, wherein the pile part yarn feeding length ratio is in the range of 1.2 or more and 2.5 or less with respect to the gland part yarn feeding length ratio 1.
The molding fabric described in Section 1.