Method for producing clothing or bedding, and clothing or bedding

Abstract

Provided are: a method for producing clothing or bedding that is tough against use in high-temperature and high-humidity environments and also can be easily disassembled into parts; and such clothing or bedding. In this method for producing clothing or bedding, when clothing or bedding (1) is produced by means of a sewing machine that uses a top thread (2) and a bobbin thread (3), a water-insoluble sewing thread made of cotton, silk, or chemical fibers, or a blend thereof, is used as the top thread (2), and a water-soluble sewing thread in which polyvinyl alcohol serves as the starting material is used as the bobbin thread (3).

Description

Clothing or bedding manufacturing method and clothing or bedding

[0001] The present invention relates to a method for manufacturing clothing or bedding using a sewing machine that uses an upper thread and a lower thread, and to clothing or bedding manufactured by this method.

[0002] In recent years, recycling of sewn products, particularly clothing, has begun to attract attention. The most efficient way to decompose sewn products is to dissolve the sewing threads. In response to this, applications have been filed for clothing constructed by joining parts made of insoluble fibers with soluble fiber threads (see, for example, Patent Document 1).

[0003] According to the garment disclosed in Patent Document 1, the garment is immersed in medium- to high-temperature water to dissolve the soluble fiber yarns, thereby leaving only the parts of the garment made of insoluble fibers, which can be recovered. Specifically, this garment is completed by sewing together garment parts such as the body and sleeves made of fibers insoluble in hot water, alkaline solution, etc., with sewing thread that is soluble in hot water, alkaline solution, etc.

[0004] As the soluble sewing thread, a fiber thread made of polyvinyl alcohol-based fiber that is easily dissolved by immersion in warm water, an alkaline solution, or the like is used (see, for example, Patent Document 2).

[0005] Japanese Patent Publication No. 8-81811 Publication No. 43-8992

[0006] However, as mentioned above, when sewing using a water-soluble polyvinyl alcohol-based soluble fiber thread as the sewing thread, if the resulting sewn product is used in a hot and humid environment, the sewing thread that connects each sewing material (piece of fabric) of the sewn product may melt, causing the sewn product to become brittle.

[0007] SUMMARY OF THE INVENTION In view of the problems of the prior art, an object of the present invention is to provide clothing or bedding that is strong enough to withstand use in a hot and humid environment and that can be easily disassembled into individual parts.

[0008] The method for manufacturing clothing or bedding of the present invention is characterized in that, when sewing materials together with a sewing machine using an upper thread and a lower thread to manufacture clothing or bedding, the upper thread is a water-insoluble sewing thread made of cotton, silk, chemical fiber, or a blend, and the lower thread is a water-soluble sewing thread made from polyvinyl alcohol, the lower thread being made of water-soluble polyvinyl alcohol fiber produced by a solvent-wet cooled gel spinning method, and being twisted under twisting conditions in which the ratio of the number of top twists to the number of first twists is within the range of 94 to 108%.Furthermore, the clothing or bedding of the present invention is characterized in that it is manufactured by the manufacturing method for clothing or bedding of the present invention.

[0009] According to the present invention, even when clothing or bedding is used in a hot and humid environment, the upper thread exposed on the front side of the clothing or bedding does not dissolve, ensuring reliable bonding of the sewing materials, thereby maintaining the strength of the clothing or bedding. On the other hand, when separating the clothing or bedding into each sewing material, the lower thread exposed on the back side of the clothing or bedding is exposed to moisture, which dissolves the lower thread and makes it easy to separate the clothing or bedding into each sewing material.

[0010] The bobbin thread is made of water-soluble polyvinyl alcohol fiber produced by the solvent-wet cooled gel spinning method, and has been twisted under twisting conditions where the ratio of the number of top twists to the number of bottom twists is within the range of 94 to 108%. Therefore, it can be used as a suitable sewing thread.

[0011] 2A to 2C are diagrams showing the degree of twist that can occur for the proper sewing thread, the slightly problematic sewing thread, and the inappropriate sewing thread obtained by the experiment in FIG. 2.

[0012] An embodiment of the present invention will now be described with reference to the drawings. Fig. 1 shows an enlarged cross section of clothing or bedding, taken along a sewing thread, produced by a method for producing clothing or bedding according to one embodiment of the present invention. As shown in the figure, this sewn product 1 is produced by joining together the sewing materials 4 that make up the clothing or bedding 1 using a sewing machine that uses an upper thread 2 and a lower thread 3. The upper thread 2 is a water-insoluble sewing thread made of cotton, silk, chemical fiber, or a blended yarn.

[0013] A water-soluble sewing thread made from polyvinyl alcohol is used as the lower thread 3. Specifically, the lower thread 3 is made by subjecting a thread made of water-soluble polyvinyl alcohol fibers obtained by a solvent-wet cooling gel spinning method (see Japanese Patent Publication No. 43-8992) to twisting (first twist and second twist).

[0014] The bobbin thread 3 may be one that dissolves in warm water at, for example, 40 to 100°C, but to ensure the strength of the bobbin thread 3 when used in a humid environment, it is preferable to use one that has a low degree of saponification and dissolves in warm water at 70°C or higher. The sewing materials 4 that are sewn together with the upper thread 2 and the bobbin thread 3 are made of water-insoluble fibers. The sewing machine that uses the upper thread 2 and the bobbin thread 3 may be, for example, a sewing machine.

[0015] Incidentally, sewing threads used in sewing machines, such as ordinary sewing threads made of cotton or silk, have a ratio of top twists to bottom twists of approximately 70%. However, the inventors' experiments have shown that this twisting condition cannot be applied to sewing threads made of water-soluble polyvinyl alcohol fibers produced by the solvent-wet cooled gel spinning method, which dissolve at temperatures above 70°C.

[0016] Figure 2 shows the results of an experiment investigating the relationship between the twisting conditions when twisting a water-soluble polyvinyl alcohol fiber yarn obtained by the solvent-wet cooled gel spinning method to obtain sewing threads and the suitability of the resulting sewing threads. The results show whether the sewing threads obtained under each twisting condition were suitable (○), slightly unsuitable (△), or unsuitable (×). The results also show the results of an experiment using two types of yarn, No. 60 and No. 30.

[0017] Figures 3A to 3C show the twist that occurs in sewing threads that are deemed to be suitable (○), slightly problematic (△), or unsuitable (×). If the sewing thread is suitable (○), there is no twist in the sewing thread, as shown in Figure 3A. If the sewing thread is slightly problematic (△), twist occurs, as shown in Figure 3B. If the sewing thread is unsuitable (×), there is a considerable amount of twist in the thread, as shown in Figure 3B, making it unsuitable for sewing thread.

[0018] In the experiment shown in Fig. 2, the twisting conditions were such that a first twist of 650 [T / m] was performed with multiple types of final twists of different numbers. In Fig. 2, the percentage of the number of final twists when the number of first twists of 650 [T / m] was set to 100 [%] was also shown.

[0019] The final twist of 455 [T / m] in Figure 2 (70% final twist rate) corresponds to the twisting conditions applied to ordinary sewing threads. The sewing threads obtained under these conditions, both for No. 60 and No. 30 threads, were found to be unsuitable (x) for use as sewing threads. Furthermore, the final twist of 768 [T / m] (118%]) was also found to be unsuitable (x).

[0020] On the other hand, there were some difficulties (△) when the final twist was 610 [T / m] and 704 [T / m], while the results were appropriate (○) when the final twist was 620 [T / m], 640 [T / m], 650 [T / m], 660 [T / m], 672 [T / m], and 682 [T / m].

[0021] As shown in FIG. 2, the appropriate twisting conditions for obtaining machine-twisted sewing threads by twisting threads made from water-soluble polyvinyl alcohol fibers that are produced by the solvent-wet cooled gel spinning method and that dissolve at 70°C or higher are such that the ratio of the number of final twists to the number of first twists for a 650 [T / m] first twist is in the range of 95 to 105 [%].

[0022] Furthermore, the twisting conditions, including those with some difficulty, exist within the range of 94 to 108%. On the other hand, if the twisting ratio is below 70% or above 118%, it is determined that there are no appropriate twisting conditions. In other words, while sewing is possible under twisting conditions in this range, as shown in Figure 3C, twisting of the yarn occurs, which is undesirable and causes problems with sewing.

[0023] When manufacturing clothing or bedding 1, first, a sewing thread made of cotton, silk, chemical fiber, or a blend that has been appropriately twisted is prepared as the upper thread 2. Then, a lower thread 3 is prepared that has been twisted under the appropriate twisting conditions shown in Figures 2 and 3A to 3C and dyed in a low-temperature environment below the melting point. Note that, since the lower thread 3 is often less noticeable than the upper thread, dyeing may be omitted, simplifying the process and reducing manufacturing costs.

[0024] Next, the upper thread 2 and the lower thread 3 are set in a sewing machine, such as a sewing machine, that uses these threads to sew. The joining portions of the two pieces of sewing material (pieces of fabric) 4 to be joined by the upper thread 2 and the lower thread 3 are then placed in a predetermined position on the sewing machine, and the sewing machine is driven to join the two pieces of sewing material 4 with the upper thread 2 and the lower thread 3.

[0025] As a result, two sewing materials (pieces of fabric) 4 are joined together as shown in Figure 1. By repeating this joining of sewing materials 4, clothing or bedding 1 is manufactured in a state where the upper thread 2 is exposed on the front side of the clothing or bedding 1 and the bobbin thread 3 is exposed on the back side.

[0026] On the other hand, when separating the clothing or bedding 1 into individual sewing materials (cloth pieces) 4, the lower thread 3 can be easily separated by exposing it to moisture and dissolving it. Exposing the lower thread 3 to moisture is carried out, for example, by storing the clothing or bedding 1 in a storage bag and immersing it in hot water of, for example, 95°C filled in a dissolving tank for, for example, 30 minutes. At this time, to promote dissolution of the lower thread 3, for example, a nonionic surfactant may be added to the hot water at a concentration of, for example, 0.01 to 20 [g / L].

[0027] As a result, the shape of the clothing or bedding 1 is maintained by the storage bag, the bobbin thread 3 dissolves, and the clothing or bedding 1 is separated into individual sewing materials (pieces of fabric) 4. The separated sewing materials (pieces of fabric) 4 are reused.

[0028] Note that when exposing the lower thread 3 to moisture, steam at 100°C or higher or hot water supplied from a hose or funnel may be used. Alternatively, moisture applied to the lower thread 3 with an iron or the like may be heated to a temperature at which the lower thread 3 dissolves. To facilitate exposing the lower thread 3 to moisture, a jig for holding the clothing or bedding 1 may be used.

[0029] According to this embodiment, even when the clothing or bedding 1 is used in a humid environment, the upper thread 2 exposed on the front side of the clothing or bedding 1 is water-insoluble and ensures the bonding of the sewing materials 4, thereby maintaining the strength of the clothing or bedding 1. On the other hand, the lower thread 3 exposed on the back side of the clothing or bedding 1 is a water-soluble sewing thread made from polyvinyl alcohol, so that by exposing the lower thread 3 to moisture, the clothing or bedding 1 can be easily separated into the sewing materials 4 and reused.

[0030] The bobbin thread 3 is made of polyvinyl alcohol fiber that can be dissolved in hot water at 70°C or higher using a solvent-wet cooled gel spinning method, and is twisted under twisting conditions where the ratio of the number of top twists to the number of bottom twists is within the range of 94 to 108%. Therefore, it can be used as an appropriate sewing thread.

[0031] Furthermore, since the lower thread 3 is dyed in an environment at a temperature lower than the temperature at which it melts, the lightness, saturation and hue of the dyeing can be adjusted as desired when viewed from the upper thread 2 side of the clothing or bedding 1. Note that since the color of the lower thread 3 does not significantly affect the appearance from the upper thread 2 side, dyeing of the lower thread 3 may be omitted to improve productivity.

[0032] 1...Clothing or bedding, 2...Upper thread, 3...Lower thread, 4...Piece of cloth.

Claims

1. A method for manufacturing clothing or bedding, in which sewing materials are sewn together using a sewing machine that uses an upper thread and a lower thread, and a water-insoluble sewing thread made of cotton, silk, chemical fibers, or a blend is used as the upper thread, and a water-soluble sewing thread made from polyvinyl alcohol is used as the lower thread, and the lower thread is made of water-soluble polyvinyl alcohol fiber produced by a solvent-wet cooled gel spinning method, and is twisted under twisting conditions in which the ratio of the number of upper twists to the number of lower twists is within the range of 94 to 108%.

2. The method for manufacturing clothing or bedding according to claim 1, wherein the lower thread is dyed in a low-temperature environment lower than the temperature at which the lower thread melts.

3. Clothing or bedding manufactured by the method of manufacturing clothing or bedding according to claim 1 or 2.

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