JPH04146226A - Raw staple for padding with high bulkiness - Google Patents

Abstract

PURPOSE:To provide the title raw staple satisfying both initial bulkiness and that after compression, suitable for coverlets with adequate bulky feeling etc., comprised of opened component and unopened component through developing crimps due to structural difference by heat treatment at a specified temperature of crimped staples of specified hollow rate. CONSTITUTION:Raw staple consisting of crimped staples with section 10-40% in hollow rate is cut and opened and then heat treated at >=120 deg.C (pref. 125-160 deg.C) to effect developing crimps due to structural difference, thus obtaining the objective raw staple comprised of (A) 10-40wt.% of opened component (number of crimps: 7-13/25mm; crimp percent: 25-40%) and (B) 90-60wt.% of unopened component (number of crimps: 3-7/25mm; crimp percent: 15-24%).

Description

[Detailed Description of the Invention] [Industrial Application Fields] The present invention provides raw cotton for stuffing with excellent bulkiness, especially having bulkiness based on the hollow structure and structural difference crimp ability, and is suitable for use in comforters. The present invention relates to suitable raw cotton for stuffing.

[Prior Art] Conventionally, raw cotton for stuffing with structural differential crimp has been known, such as fibers obtained by asymmetric cooling of hollow or non-hollow fibers or composite or multilayered fibers made of polymers with different degrees of polymerization. Yes, it is widely put into practical use.

However, even with such raw cotton for stuffing, the quality and performance of the cotton in its current state are by no means satisfactory, and various proposals have been made for improvements.

For example, Japanese Patent Publication No. 56-34658 discloses that by specifying the mechanical crimping conditions for hollow polyester fibers for stuffing wire, the heat treatment conditions after crimping, etc., it is possible to make stuffing cotton for a long period of time. It has been shown that the so-called "sagging" phenomenon, such as a decrease in bulkiness and compression resistance, can be prevented during use.

In this way, if the conditions for crimping the hollow polyester fiber for stuffing wire and the heat treatment conditions after crimping are specified,
Although it is possible to prevent the phenomenon of "sagging" of stuffed cotton to some extent, the level of bulkiness of conventional stuffed cotton itself is not fully satisfactory, and therefore, there is a problem of preventing "sagging" phenomenon, especially in the field of comforter cotton. In addition, how to improve the overall level of bulkiness has become an important consideration.

[Problem to be solved by the invention] The object of the present invention is to provide raw cotton for stuffing as described above.

In particular, for use in comforters, we have further improved the overall level of bulkiness based on the hollow structure and differential crimp ability of the structure.
To provide high-quality, high-performance futon cotton for comforters, which gives a sense of thickness even though the comforter itself is light, and has excellent draping properties at the shoulders and the like.

[Means for Solving the Problems] The above object of the present invention is to provide a structural differential crimped staple having a cross section with a hollowness ratio of 10 to 40%, in which a 10 to 40% opened portion and the remainder are unopened fibers. This problem can be solved by using raw cotton for stuffing, which has excellent bulkiness and is made up of several sections and whose staples are heat-treated at a temperature of 120° C. or higher.

Hereinafter, the configuration of the present invention will be specifically explained.

That is, the raw cotton for stuffing according to the present invention (hereinafter simply referred to as raw cotton), particularly for use in comforters, is required to have superior bulkiness.

For this purpose, first, hollow fibers having a hollowness ratio of 10 to 40% and a structural differential crimp ability are used.

At this time, fibers with a hollowness ratio of less than 10% are difficult to obtain sufficient bulkiness, while on the other hand, when the hollowness ratio exceeds 40%, cracks occur in the hollow part of the fibers due to the cloth of the card during cotton manufacturing, and the fibers cannot be used as raw cotton for stuffing. is inappropriate.

The hollow ratio here refers to the ratio (%) of the cross-sectional area of the hollow portion to the apparent cross-sectional area of the fiber, and is a value obtained by.

Next, the bulk properties of the raw cotton are generally controlled by the crimp properties, but sufficient bulk properties cannot be obtained simply by keeping the crimp properties within a certain range. In other words, the bulk characteristics of raw cotton are mainly determined by applying a load of 5 g/d to 40 g of a carded sample cut to a size of 20 cm on the initial bulk knee side, and determining the height of the sample after 30 seconds have elapsed. , initial bulk (c, c/g).

b. Compression bulk: Change the above load to 10 g/a (30
The height of the sample after seconds has passed is the compressed bulk (C, C/g)
shall be.

Of these bulky characteristics, as indicated by.

The initial bulk has a peak value within a certain range of crimp numbers.

The initial bulk becomes lower before and after that. Although this bulky peak varies depending on the crimp type, it is generally said that the number of crimp is around 6 to 9 crimp/25 crimp. On the other hand, the compressed bulk increases approximately in proportion to the number of crimps. For this reason, when setting the crimp characteristics of conventional raw cotton for stuffing, emphasis is placed on either the initial bulk or compressed bulk (i.e., one of the initial bulk and compressed bulk is sacrificed). The crimp characteristics have been set depending on the bulkiness of the material.

In contrast, in the present invention, in order to satisfy both the characteristics of initial bulk and compressed bulk as raw cotton for stuffing, fibers having crimp characteristics that match the bulk characteristics of initial bulk and compressed bulk are mixed in raw cotton. In other words, the invention is characterized by widening the distribution of crimp characteristics in the raw cotton over a certain range, and as a specific technical means, after controlling the opening state of the raw cotton within a predetermined range, , heat treatment is performed.

In other words, ordinary structurally crimped fibers develop structurally differentially crimped by heat treatment, but the crimping is influenced by the binding force between the single fibers, and when the binding force is large, crimping does not occur. is significantly suppressed. That is, the crimp characteristics vary depending on the spread state of the fibers, in other words, the composition ratio of the spread portion and the unspread portion. Therefore, if the composition ratio of both the spread part and the unspread part is controlled within a certain range, raw cotton having at least two crimp characteristic distributions can be obtained by combining the structural crimp expression ability of the fiber itself. It is.

Therefore, in the raw cotton of the present invention, the proportion of the spread portion in the raw cotton is 10 to 40%, preferably 15 to 30%.
The remaining part is kept as an unopened part. At this time, if the spread portion in the raw cotton is less than 10%, the compressed bulk will be low, while if it exceeds 40%, the compressed bulk will improve, but the initial bulk will be low. In other words, if the ratio of the opened fiber portion to the unspread portion in the raw cotton is outside the range specified in this application, the
The initial bulk is determined by the unopened portion, which accounts for ~90%, and the compressed bulk is determined by the opened portion, which is less than 40%, making it impossible to simultaneously improve both initial bulk and compressed bulk.

The spread part of the raw cotton referred to here refers to the fiber part in which each fiber is sufficiently separated, and the unopened part refers to the so-called chip-shaped or scallop-shaped part in which single fibers are grouped together. This is the part.

Next, the raw cotton of the present invention has a temperature of 120°C or higher, preferably 1
It must be heated at a heat treatment temperature of 25 to 160°C. If the heat treatment temperature at this time is less than 120 degrees Celsius, structural differential crimp will not occur easily, so not only will it not be possible to use it as raw cotton for stuffing, but even if some crimp occurs, heat fixation will be insufficient and it will not be used for a long time. When this occurs, "sagging" occurs due to external force.

Such heat-treated raw cotton further has a number of crimps of approximately 7 to 13 crimps/25 mm in the spread portion, and a crimp degree of approximately 25 to 40%, and a number of crimps of approximately 3 to 7 crimps/25 mm in the unspread portion.

It is desirable to have crimp characteristics of 15 to 24% in terms of crimp degree. To achieve this, it is necessary not only to control the composition ratio of the spread part and the unspread part mentioned above, but also to control the asymmetric cooling conditions during spinning (chimney wind speed, temperature), or the difference in the degree of polymerization, etc. It is desirable to enhance the ability to express structural differential crimp.

Next, an example of manufacturing raw cotton for stuffing according to the present invention will be described using polyethylene terephthalate polyester fiber.

That is, a polyethylene terephthalate polymer is melt-spun using a hollow fiber spinneret by an asymmetric cooling method.

At this time, the ability of the fiber to develop crimp is determined by cutting the undrawn yarn into three pieces, and measuring the diameter of the undrawn yarn curling after treatment in clean water for 5 minutes. (abbreviated as function 1/d). The smaller this value is, the higher the ability to develop crimp is, usually about 0. 25-0. A range of 40 (mm) is desirable. Furthermore, as described above, in the asymmetric cooling method, this crimp development ability 1/d is usually controlled mainly by the cooling conditions of the spun yarn or by the difference in the degree of polymerization.

The spun yarn (undrawn tow) is heated in a steam drawing bath or hot water drawing bath for about 2. Stretch 0 to 3.5 times.

If necessary, the tow after stretching may be mechanically crimped using a push-in crimper or the like, but the number of crimps in this case is preferably about 1 to 4 crimps/25 mm.

The drawn tow is cut to a fiber length of approximately 51-80 mm.

Next, the raw cotton after cutting is subjected to a fiber-spreading process using a fiber-spreading machine so that about 10 to 40% of the raw cotton is spread, and the remainder is unspread.

The aim of this opening treatment for cut cotton is to obtain fibers with at least two distributions of crimp characteristics in the raw cotton, based on the difference in crimp ability between the opened portion and the unopened portion. . Therefore, in the raw cotton of the present invention, the opening part is 1
It is important to keep it within the range of 0 to 40% (unopened portion; 60 to 90%). The proportion of the spread portion in the raw cotton is desirably set within the above range, taking into consideration the relationship between the ability of the fiber itself to develop structural differential crimp and the heat treatment applied to the fiber after opening. In this case, the opening means used includes spikes used in staple spinning, opening means using air, etc., and an opener that rotates blades facing each other.

The cut cotton after the opening treatment is further subjected to heat treatment at 120°C or higher, preferably about 125 to 160°C.

At this time, heat treatment means used include a tunnel type heat treatment machine using hot air circulation, and a method of heat treatment using hot air at the same time as fiber opening.

In addition to the above-mentioned requirements, the bulkiness of the raw cotton of the present invention is also controlled by the single yarn denier, heat shrinkage rate, and the like. Therefore, the single yarn denier is approximately 4 to 8 denier,
It is desirable that the shrinkage rate be within the range of about 2-7%.

It goes without saying that the raw cotton for stuffing in the present invention is not limited to the hollow fibers produced by the asymmetric cooling method described above, but also includes composite hollow fibers and the like.

[Example] The present invention will be specifically described below with reference to Examples.

In addition, in the evaluation results in this example, ◎: Good, ○: Fairly good, △
; Slightly poor; ×; Indicates poor.

Example 1 The intrinsic viscosity determined at 25°C in 0-chlorophenol was 0.
No. 65 polyethylene terephthalate polymers were each melt-spun at 290° C. by an asymmetric cooling method using hollow fiber spinnerets (60 holes) with different hollow ratios as shown in Table 1. The spun yarn with a single yarn fineness of 18 denier is approximately 13
00m/min.

These spun yarns (undrawn yarns) were bundled into a tow of approximately 300,000 denier, stretched to 2.8 times with pressurized steam using a conventional method, and then stretched to approximately 3 peaks/25 mm using a push-in crimper. After applying a certain degree of crimp, it was cut to a size of 750 mm. The cut cotton was then opened using a opening machine with the composition ratio of the opening portion (hereinafter simply referred to as opening ratio) set at 25%.

After opening, the cut cotton was further heat-treated at about 140° C. for 20 minutes using a hot air circulation heat treatment machine to develop structural differential crimp.

Futon cotton is prepared from these cut cotton in the usual manner,
Initial bulk, compressed bulk, and texture were evaluated. We also conducted a wearing test on a prototype comforter made from the futon cotton.

These results are shown in Table 1.

(Hereinafter, blank spaces) Table 1 Example 2 Example 1. At level 5, the opening rate during the opening process was changed, and the initial bulk, compressed bulk,
and the relationship with texture.

These results are shown in Table 2.

Table 2 Example 3 Example 1. In Level 5, the heat treatment temperature during the crimp development treatment was changed, and the relationship between the heat treatment temperature and the initial bulk, compressed bulk, and texture of the resulting cut cotton was investigated.

These results are shown in Table 3.

(Hereinafter, blank spaces) Table 3 Example 4 Example 1. In level 5, the chimney wind speed (air temperature: 16°C) during asymmetric cooling during spinning was changed, and the crimp characteristics, bulk characteristics, and The relationship between texture was investigated and shown in Table 4.

(Hereafter, margin) Table 4 [Effect of the invention] As mentioned above, the present invention is used as raw cotton for stuffing cotton.

The key point of the invention lies in limiting the composition ratio of the spread portion and unspread portion in the structurally differentially crimped fiber having a hollow cross section, and the heat treatment temperature, thereby simultaneously increasing both the initial bulk and the compressed bulk. Because the comforter is fully filled, even though the comforter itself is light, it has sufficient thickness and heat retention, and has excellent drapability over the shoulders and other areas. The effects of the fibers of the present invention, especially for use in duvets, are remarkable.

Claims (2)

[Claims] (1) A differentially crimped staple with a cross section with a hollowness ratio of 10 to 40%, consisting of a 10 to 40% opened portion and the remainder of the unspread portion, and the temperature at which the staple is subjected to heat treatment is Raw cotton for stuffing with excellent bulk and temperature of 120℃ or higher. (2) In claim (1), the spread part has 7 to 13 crimps/25 mm, the crimp degree is 25 to 40%, and the unopened part has 3 to 7 crimps/25 mm, Crinkage degree 15-2
Raw cotton for stuffing with excellent bulk and a crimp property of 4%.