JPH0115614B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a nonwoven fabric and a method for producing the same. More specifically, it is made of a long-fiber nonwoven fabric coated or impregnated with a resin, and has fiber weak points and fiber fluff on one or both sides of the nonwoven fabric, as well as micropores that allow ventilation. This paper relates to a novel nonwoven fabric and its manufacturing method. [Prior Art] Conventionally, nonwoven fabrics have been manufactured by spunlace, spunbond, jet spinning, etc., all of which typically use some kind of convergence means to maintain their fabric form. That is, for example, means such as entanglement, adhesion using a binder, and even thermal adhesion can be used. When considering the use of nonwoven fabrics in clothing, it is necessary to have at least the following properties. In other words, it provides anti-plumping and pilling properties, anti-pilling properties, breathability, dimensional stability, skin adhesion (flexibility), durability, etc. . However, since nonwoven fabrics are not common materials for clothing, the reality is that they have hardly been studied. [Problems to be solved by the invention] Here, if a large amount of resin is impregnated with the purpose of preventing the occurrence of puckering and pilling among the above properties, it will not only give a paper-like texture with a rough and hard feel. Breathability is extremely deteriorated, resulting in unsatisfactory clothing performance. On the other hand, if the amount of resin is kept low in order to take advantage of flexibility, the above-mentioned puckering and pilling will occur, resulting in a fatal defect such as a significant deterioration of the appearance. The object of the present invention is to provide a flexible nonwoven fabric that does not cause puckering or pilling, which is essential for making into clothing, and to provide a novel method for manufacturing the nonwoven fabric. [Means for Solving the Problems] In order to achieve the above object, the present invention has the following configuration. That is, the nonwoven fabric of the present invention is a nonwoven fabric formed by coating or impregnating a laminated sheet made of continuous filaments with a resin, and the single fibers arranged on the surface layer of one or both sides forming the nonwoven fabric include This nonwoven fabric is characterized by having weak points and cut areas (fluff), and the presence of fine ventilation holes in the nonwoven fabric. In addition, the method for producing a nonwoven fabric of the present invention includes a spinning process, a process of collecting spun continuous filaments into a sheet, and a process of imparting entanglement to the collected fiber sheet. A first step to obtain a laminated sheet, a second step of coating or impregnating the fiber laminated sheet with a resin, a third step of pressing the fiber laminated sheet with a rough surface having protrusions, and then This method of manufacturing a nonwoven fabric is characterized by comprising a fourth step of subjecting the fiber laminated sheet to a punching treatment. Preferred embodiments of the nonwoven fabric or the method for producing a nonwoven fabric of the present invention will become clearer in accordance with the following description. [Operation] The present invention will be explained in more detail below. The nonwoven fabric of the present invention is formed from continuous long fibers made of a monopolymer or modified polymer having a main chain of polyethylene terephthalate, polyamide, polyacrylonitrile, polyethylene, polypropylene, polysulfide polyimide, or polybutylene terephthalate. be. The continuous long fibers include ordinary single-component fibers as well as
The single fiber may be a conjugate fiber exhibiting a sea-island structure, or a splittable conjugate fiber made of a combination of different polymers. Further, the fiber cross-sectional shape is not particularly limited, and various shapes such as a general round cross section to various irregularly shaped cross sections can be used. Furthermore, the various fibers, various composite fibers, various cross-section fibers, etc. made of the above-mentioned polymers may be used alone or in combination of two or more. The fineness of such continuous long fibers is not particularly limited, and can be applied from around 0.01 denier to several tens of deniers, but when aiming for general clothing, it is in the range of 0.05 to 5 denier. It is preferable to set it within the range, and this may be determined as appropriate depending on the desired characteristics of the nonwoven fabric. For example, when using ultrafine fibers and aiming for particular flexibility, sea-island type composite fibers should have a single fiber denier within the range of 0.01 to 1.0 after the sea component has been eluted, and splittable type composite fibers should have a split denier of 0.01 to 1.0. It is preferable to use fibers whose single fiber denier after splitting is within the range of 0.05 to 5.0. Also,
For conventional melt spinning of conventional mono or modified polymers, the denier is preferably within the range of 0.1 to 5 denier. In addition, when the single fiber fineness is small, for example, 0.01 to 0.05 denier, the fiber density in the laminated sheet increases and the entanglement itself improves, resulting in a nonwoven fabric that does not easily flop. Since it is easy to cut, the occurrence of snags and pilling is actually extremely low, and from this point of view it can be said to be preferable. On the other hand, if the fineness of the single fiber exceeds, for example, 5 denier, the rigidity of the single fiber increases, so the flexibility tends to gradually decrease, but if it is permissible for the purpose, there is no problem with it. . The nonwoven fabric of the present invention uses, as a raw material, a nonwoven fabric (fiber laminated sheet) formed using at least the above-mentioned continuous long fibers as starting filaments. The fiber laminated sheet is produced by a process of spinning continuous long fibers, collecting the spun continuous fibers into a sheet, and a process of collecting the spun continuous fibers into a sheet, which have been conventionally adopted as a method for producing a long fiber nonwoven fabric. It is manufactured in the first step of the present invention, which mainly includes a step of imparting entanglement to the fiber sheet-like material. The step of imparting entanglement in the first step may be any method such as waterjet punching or needle punching, but
Water jet punching is preferred in order to obtain the desired soft feel. Further, in the present invention, as a second step,
The fiber laminated sheet is impregnated or coated with at least a resin such as a polymeric elastomer to provide inter-fiber reinforcement, and then in the third step, one or both sides of the nonwoven fabric containing the resin is coated with emery paper or emery cloth. Coarse-grained trachyhedra, such as
Or diamond, ceramic, alumina,
Coarse-grained roughened bodies coated with granular materials such as titanium oxide or glass, or coarse-grained roughened bodies made by roughening surface protrusions by buffing etc. of molded products made of these are pressed together. Then, at least a weak point is created in the fibers constituting the sheet on one or both sides of the fiber sheet, and then, as a fourth step, a punching process to be described later is performed to cut the fibers at the weak point and destroy the resin layer. . Therefore, in the nonwoven fabric of the present invention, weak points and cut portions (fuzz) are present in the single fibers mainly arranged in the surface layer on one or both sides forming the nonwoven fabric.
This means that there is. Although the above-mentioned pressure welding is carried out mainly for the purpose of imparting a weak point to the constituent fibers, it does not matter if the constituent fibers are cut to some extent by the pressure welding. There are no particular limitations on the pressure welding process of the coarse-grained roughened bodies, but according to the studies of the present inventors, it is convenient to use the above-mentioned roughened bodies, and even in that case, the actual processed yarn is Although not particularly limited, the weak point imparting processing system may be configured with a pressure roller system or a pressure plate system having the coarse grain surface, and the processing system may apply pressure to the fiber laminated sheet flowing along the process. It is practical to apply According to the findings of the present inventors, it is important to set the roughness of the coarse-grained trachyhedron to a coarse grain surface with an average roughness of 1 to 5000μ, preferably an average roughness of 50 to 5000μ.
It is preferable to set it within a range of about 500μ. This corresponds to the Emery Cross standard and is #40~
Equivalent to about #600. The pressing load during pressure welding varies depending on the characteristics of the fibers that make up the fiber sheet.
Although there are some points that cannot be stated unambiguously, the most important point is that the pressure welding imparts a weak point to the fiber group constituting the fiber sheet, and that the fibers are cut in some of the weak points. Moreover, it is preferable that the fibers be easily cut and the resin destroyed in the high-pressure water jet punching process (waterjet punching) or needle punching process, which is the fourth process described later. In addition,
Such pressure contact may cause destruction of the resin layer applied in the second step, and in this case, micropores will also be created due to the destruction. The punching treatment, which is the fourth step in the method of the present invention, has two main purposes: as described above, the punching causes the fibers to be cut at weak points and fluffs them, and also to provide a large number of fine through holes in the nonwoven fabric. It is something. However,
The nonwoven fabric according to the present invention exhibits the feel, appearance, and feel of a short fiber nonwoven fabric, and has air permeability due to the presence of through holes. Such punching treatment may be performed by waterjet punching, needle punching, etc., but waterjet punching is preferred in order to obtain the desired soft feel. That is, by such waterjet punching or needle punching, the fibers are cut and the cut fluff ends penetrate the fabric layer and protrude to the back side, resulting in a nonwoven fabric with naps, and at the same time, the resin deteriorates due to pressure welding. The membrane components are destroyed and numerous vent holes are created. In addition to cases in which almost all of the cut fluff ends protrude to the back surface, there are cases in which not all of the cut ends necessarily protrude to the back surface and some of them remain inside the nonwoven fabric. The nonwoven fabric obtained in this way may be used as a product as it is, or it may be further subjected to appropriate post-processing (such as surface brushing, surface unevenness imparting, surface sliminess imparting) to give surface effects and texture changes. Needless to say, it can also be used as a final product. In the above-described method of the present invention, the first step may also include a step of pressing the fiber sheet with a rough surface having projections. By doing so, the effect of imparting weak points can be enhanced and a further fluffing effect can be expected. Here, to explain in more detail about the resin-containing nonwoven fabric used for needle punching and water jet punching, typical examples of resins that can be used in the present invention include polymers such as polyurethane resins. It is an elastic body, and the amount of the resin attached is as follows: Weight of nonwoven fabric without resin applied; A Weight of nonwoven fabric after applying resin; B Weight of adhered resin; C (equivalent to B-A). For example, the A/C weight ratio is 99/1 to 20/
preferably in the range of 80, most preferably
It is best to set it within the range of 95/5 to 70/30. When impregnating a polymer elastomer, the resin amount is 1%.
If it is less than that, the fabric will be highly flexible, but it will tend to have poor anti-pilling properties and softness. On the other hand, if it exceeds 80%, the anti-pilling properties and momoke will be at a level that is sufficiently satisfactory for practical use, but the roughness and hardness will increase and the texture will tend to deteriorate. The amount of the resin to be applied is not particularly limited in the present invention, but may be appropriately determined in accordance with the desired nonwoven fabric texture, nonwoven fabric properties, etc., keeping the above matters in mind. In addition, it is preferable that B of the present invention, that is, the basis weight of the nonwoven fabric after applying the resin, is 20 to 300 g/m ² . Impregnation or coating with the polymeric elastomer such as the polyurethane resin can be carried out by either a wet method or a dry method. In the case of the former method, the polyurethane resin generally exhibits a microporous honeycomb structure due to foaming, so it is flexible. Suitable for impregnation or coating processing where a desired texture is desired. In the latter dry method, the solvent is blown away in the air and is suitable for thin film surface coating. Impregnating or coating with a polymeric elastic material (resin) is highly effective in bonding and elasticity between fibers, preventing residual strain after elongation (elasticity, crease removal), and improving durability. It is. In the present invention, after impregnating or coating with the resin, any one or more of the following post-processing may be performed, such as calendar pressing, embossing, buffing (raising), and wrinkle-imparting processing. It may also be processed. Particularly regarding these processes, calender press processing is effective in smoothing the surface, imparting gloss, and imparting a thin texture, and also has a blinding effect, and is also effective in further improving heat retention. Furthermore, embossing changes the surface (grain, touch, gloss) of the fabric, and is particularly effective in improving gloss. In addition, buffing (napping) is effective in raising the nap and making it soft to the touch. Further, the wrinkle-imparting process produces a wrinkle structure on the surface, which has a large effect of improving fashionability. The nonwoven fabric obtained by the present invention has anti-pilling performance.
Generally shows grade 3 or higher by ICI method (after 5 hours),
It has excellent anti-pilling properties. here,
To explain this anti-pilling property in detail, ICI, which is commonly used for knitting fabrics as a method for determining pilling.
It is rated on a 5-point scale according to the law, and in addition, with the addition of this pure pilling evaluation,
The presence or absence of peach was evaluated by evaluating the fuzziness of the evaluation fabric. It goes without saying that pilling occurs in the initial stage when fluff becomes entangled with each other to form minute naps, and then the fibers slip off and grow from naps to pilling (pilling), which significantly reduces the surface quality. Since the inter-fiber binding force of non-woven fabrics is extremely small, it is common for pilling to occur in a short period of time. In particular, nonwoven fabrics made of long fibers have a weak inter-fiber binding force due to migration compared to those made of short fiber webs, and since they are long fibers, once the naps become tangled, the fibers will inevitably slip off, resulting in pilling (momoke). This is a common problem in that it tends to occur. In contrast, in the present invention, by adding weak points and breaking the continuity of the fibers by cutting the fibers, and in addition, by adopting a structure in which the fibers are bonded with resin, anti-pilling and prevention of peach formation are achieved. It exhibits excellent effects. Furthermore, even when impregnated with resin, the amount of resin impregnated can be minimized, and the fabric can exhibit a spuntouch feel due to fluff, making it possible to create a fabric with a more natural feel. By suppressing the amount of resin impregnated in this way, a fabric with high breathability can be obtained, making it possible to create comfortable clothing. Furthermore, in the present invention, the sharp convex portions of the coarse grained protrusions are destroyed in the thickness direction of the fabric by pressure, and as a result, fine ventilation holes can be generated, which further improves the passing performance. It will improve. It is important that the degree of such destruction is such that the tearing strength by the Elmendorf method does not fall below 0.5 kg. When the value falls below 0.5 kg, the durability is extremely reduced and it tends to be difficult to use it as clothing. To explain the present invention in more detail with reference to the drawings, FIG. 2 shows a model of a conventional laminated sheet 2 of continuous long fibers 1, and shows a model of the state of fiber entanglement caused by water punching or needle punching. It shows. FIG. 3 shows a model of the laminated sheet 1 of FIG. 2 impregnated with resin 3, and corresponds to the base fabric 4 for obtaining the nonwoven fabric of the present invention. 1st
The figure shows an enlarged model diagram of the nonwoven fabric 6 according to the present invention, and shows the weak point A of the continuous long fibers 1.
(indicated by a V symbol), cut portion B and microvent hole C are shown, respectively. The fine pores C are randomly distributed, and according to the findings of the present inventors, the frequency of their presence is preferably 1 pore/cm ² to 30 pores/cm ² or less.
If it is less than 1 piece/cm ² , air permeability decreases, which is not preferable.
On the other hand, if it exceeds 30 pieces/cm ² , the air permeability is good, but the strength of the fabric decreases, which is not preferable in terms of durability. FIG. 4 shows a flowchart of one embodiment showing an example of a process for obtaining the nonwoven fabric 6 of the present invention. FIG. 5 shows that the base fabric 4 obtained through the first and second steps in FIG. This figure shows an outline of the process of interlacing, cutting fibers at weak points, and destroying the resin film in the interlacing device 7. In the figure, 8 and 8' are squeezing rolls, 9 and 9' are winding rolls, 10 indicates a net conveyor belt. The coarse-grained coarse surface bodies of the pressing treatment devices 5 and 5' are, for example, sheet-like materials coated with powders of zirconia, alumina, silicon carbide, garnet, diamond ceramic, titanium oxide, glass, etc., in a flat plate type or roll type. In the latter case, the material is not limited to the sheet-like material described above, and may be made into a roll alone. A plurality of these roles may be combined. [Example] The present invention will be explained below with reference to Examples. Example 1 A polyamide-based polymer was spun at high speed to have a single fiber fineness of 0.5 denier (the fineness after taking it off from the ejector), and was scattered onto a net conveyor belt to obtain a tentatively set nonwoven fabric with a basis weight of 50 g/m ² . The nonwoven fabric was heated with a nozzle diameter of 0.14 mm, a pitch between nozzles of 1.1 mm, and water pressure.
Preliminary entanglement using a waterjet punch was performed once on each front and back under the condition of 40Kg/cm ² , and then full-scale entanglement was carried out once on each of the front and back under 50Kg/cm ² . After drying the nonwoven fabric, it was impregnated with a polymeric elastic material (polyurethane resin) at a weight ratio of 78/2 (grey nonwoven fabric/resin), and then fed between rolls equipped with emery cloth of mesh number #150. Line pressure 40
Pressure treatment was performed at kg/cm. Following the pressing treatment, water punching treatment was performed at a water pressure of 65 kg/cm ² . The nonwoven fabric thus obtained has fluff,
It has a soft feel and is excellent in anti-pilling and anti-pilling properties. In addition, the performance was evaluated using a nonwoven fabric that was not subjected to the pressing treatment under the above-mentioned conditions as a comparative example, and the results were as shown in Table 1.

[Table] As is clear from Table 1, the anti-pilling property of the product of the present invention maintained grade 4 even after 10 hours, which fully satisfies the practical level. On the other hand, the comparative product was observed to deteriorate rapidly in the initial stage of evaluation (1 to 2 hours), suggesting that the single fibers easily slipped off. In addition, in terms of air permeability, the fabric of the present invention showed a value about 7 times higher than that of the comparative product, resulting in a fabric with less stuffiness. In addition, the fabric of the present invention was overwhelmingly superior in terms of soft feel. Example 2 Single fibers made of polyethylene terephthalate with a fineness of 1.3 denier (after being taken up by the ejector) were spun at high speed and scattered onto a net conveyor belt to obtain a temporarily set laminated sheet with a basis weight of 65 g/m ² . The laminated sheet was subjected to water jet punching once on each front and back at a nozzle diameter of 0.14 mm, pitch between nozzles of 1.0 mm, and water pressure of 30 Kg/cm ² , and then the same treatment at 50 Kg/cm ² once on each front and back. The resin was wet-impregnated. The amount of resin was 18.8% of the overall fabric weight ratio. The fabric was subjected to pressing treatment (passed three times) using a roller equipped with mesh number #120 emery cloth. The linear pressure was 60Kg/cm ² . Subsequently, water jet punching treatment was performed at a water pressure of 60 kg/cm ² . Both the thus obtained nonwoven fabric according to the present invention and a fabric before being subjected to pressing treatment for comparison were subjected to performance evaluation, and the results were as shown in Table 2.

〔Effect of the invention〕

The effects of the present invention are listed below. In other words, the resulting nonwoven fabric has high pill resistance. This is based on the anti-slip effect due to interruption of the continuity of single fibers. It has high ventilation performance. This is based on the effect of providing ventilation holes. It has a soft touch and drapability. This is based on the presence of surface fuzz. It has little slimy feel (waxy feeling) and has a mild luster. This is thought to be due to the fact that the pressing treatment also imparts a fine uneven structure to the surface of the fabric. Through the above steps, it has become possible to create clothing made of nonwoven fabric that is high quality and has excellent performance, which has not been seen before. Moreover, according to the method of the present invention, the novel nonwoven fabric as described above can be obtained relatively easily without requiring any major changes compared to conventional nonwoven fabric manufacturing processes.

[Brief explanation of drawings]

FIG. 1 shows an enlarged model diagram of a nonwoven fabric 6 according to the present invention. FIG. 2 shows a model of a conventional laminated sheet 2 of continuous long fibers 1, and shows the state of fiber entanglement by water punching or needle punching. Figure 3 shows the laminated sheet 1 in Figure 2.
This is a model of the material impregnated with resin 3. FIG. 4 shows a flowchart of one embodiment showing an example of a process for obtaining the nonwoven fabric 6 of the present invention. FIG. 5 shows that the base fabric 4 obtained through the first and second steps in FIG. This figure shows an outline of the process in which the interlacing device 7 performs interlacing, cutting fibers at weak points, and destroying the resin film. 1: Continuous long fiber, 2: Laminated sheet, 3: Resin,
5: Press treatment device, 6: Nonwoven fabric according to the present invention,
A: Weak point, B: Cut portion, C: Fine ventilation hole.

Claims (1)

[Scope of Claims] 1. A nonwoven fabric formed by coating or impregnating a laminated sheet-like material made of continuous long fibers with a resin, in which the single fibers arranged on the surface layer of one or both sides forming the nonwoven fabric have weak points. section and cut section (fuzz)
1. A nonwoven fabric characterized in that the nonwoven fabric has fine air holes. 2. A first step for obtaining a fiber laminated sheet, which mainly includes a spinning step, a step of collecting spun continuous filaments into a sheet shape, and a step of imparting entanglement to the collected fiber sheet material; , a second step of coating or impregnating the fiber laminated sheet with a resin, a third step of pressing the fiber laminated sheet with a rough surface having projections, and a subsequent step of punching the fiber laminated sheet. A method for producing a nonwoven fabric characterized by comprising four steps. 3. The method for producing a nonwoven fabric according to claim 2, wherein the punching treatment is a waterjet punching treatment. 4. The method for producing a nonwoven fabric according to claim 2 or 3, wherein the first step also includes a step of pressing the fiber sheet with a rough surface having projections.