JP5789385B2 - Laminated nonwoven fabric for pipe-type coating materials and pipe-type coating materials - Google Patents

Description

  The present invention relates to a pipe-type coating material useful for coating an object, and in particular, binds a covered electric wire or wiring used in various heavy electrical machines, electrical appliances, automobiles, or other members (particularly long members). The present invention relates to a binding material useful for protection; a protective material useful for covering and protecting a linear object, a rod-like object, or a plate-like object.

  As binding materials for various types of covered electric wires and wiring, polyolefin resin coating materials (Patent Document 1 etc.), heat-shrinkable polyester film (Patent Document 2 etc.), slanted in the axial direction of a tube made of rubber or synthetic resin There are known those in which a linear cut is provided (Patent Document 3, etc.). A binding method is also known in which a spiral cut is made in a heat-shrinkable tube, processed into a spiral wrap, wound around an optical fiber, and heat-shrinked (Patent Document 4, etc.). However, these binding materials have problems such as being hard and difficult to follow the shape of the object to be bound, having a poor cushioning property, and requiring work to be crafted.

  As a protective material or a method of using the same, a method is known in which an object is covered with a high-shrinkage nonwoven fabric to protect the object, and the high-shrinkage nonwoven fabric is thermally shrunk (Patent Document 5, etc.). In addition, a bulky highly shrinkable nonwoven fabric is used for the wiper or the like (Patent Document 6, etc.). However, these non-woven fabrics do not become pipe-shaped even when thermally contracted.

  In addition, patent documents 7-9 etc. are known as a pipe-shaped thing made from a nonwoven fabric, for example. In patent document 7, the pipe-shaped thing is produced by needling the structure of a nonwoven fabric to cylindrical shape. In Patent Document 8, a cylindrical nonwoven fabric is produced by stitching both side edges of a sheet-like nonwoven fabric. In the techniques of Patent Documents 7 and 8, there is a problem that a special machine is required and it is difficult to make a large-diameter pipe-like material, or that it takes time for sewing. Patent Document 9 describes that a laminated sheet is three-dimensionally bent by heat shrinkage of heat-shrinkable fibers, and this is used as a carrier for adhesion of microorganisms. The present invention is completely different from the present invention in terms of use, problems (required characteristics), and the like.

JP 2006-179552 A Japanese Patent Laid-Open No. 6-100671 JP 2005-287176 A JP-A-2005-207577 JP 2003-336151 A JP-A-9-67748 Japanese Patent Laid-Open No. 11-279921 JP-A-7-304099 JP-A-8-243579

  The present invention has been made by paying attention to the above-described circumstances, and an object of the present invention is to provide a laminated nonwoven fabric for a pipe-type covering material that is not easily deformed and can be easily handled on site.

  As a result of intensive studies to solve the above problems, the present inventor has laminated fiber layers (nonwoven fabrics) having different heat shrinkage rates. It is a well-known physical phenomenon that the higher the difference in weight ratio, thickness ratio, and thermal shrinkage between the upper and lower layers, the greater the bimetal phenomenon that causes curling, and when this laminate is heated, A pipe type covering material (for example, a protective material, a binding material, etc., preferably a binding material) is formed in order to curl with a layer exhibiting a phenomenon and a large heat shrinkage rate inside, and this pipe type covering material is a fiber. Because it is a product, it has cushioning properties and is not easily deformed, and since it can be easily formed into a pipe shape with hot air, it is easy to work on site, and the laminated nonwoven fabric is appropriately cut and heated. Thus, the inventors have found that a desired diameter and length can be easily manufactured at the site, and have completed the present invention.

That is, the laminated nonwoven fabric for pipe-type covering materials according to the present invention is a laminated body of first and second fiber layers. The first fiber layer is mechanically entangled with a high-melting fiber that is at least one selected from thermoplastic fibers having a melting point of 150 ° C. or higher, natural fibers, and glass fibers, and a low-melting fiber A having a melting point of less than 150 ° C. A non-woven fabric layer, the weight ratio of the high-melting fiber and the low-melting fiber A (the former / the latter) is 60/40 to 90/10, and the thermal shrinkage SHD _{1 at} a temperature of 150 ° C. is 5% In addition to the following, the basis weight is 30 g / m ² or more and less than 350 g / m ² . The second fiber layer is a non-woven fabric layer in which a high heat-shrinkable fiber capable of shrinking by 30% or more at a temperature of 130 ° C. and a low-melting fiber B having a melting point of less than 150 ° C. are mechanically entangled, and the high heat shrinkability The weight ratio of the fiber to the low-melting fiber B (the former / the latter) is 30/70 to 95/5, the thermal shrinkage SHD _{2 at} a temperature of 150 ° C. is 15% or more, and the basis weight is 50 to 500 g / m ² . The weight ratio (the former / the latter) of the first fiber layer and the second fiber layer is 70/30 to 15/85, and the difference in heat shrinkage rate between the first and second fiber layers at a temperature of 150 ° C. (SHD ₂ -SHD ₁₎ is 10 to 50%. The high heat-shrinkable fibers are preferably oriented in a substantially constant direction within the plane direction, and the area of the plane used is preferably 100 cm ² or more.

  The pipe type covering material is a circular pipe shape or a C type pipe shape obtained by curling the laminated nonwoven fabric for pipe type covering materials by heating, and a slit is formed in the axial direction. The pipe-type covering material is curled so as to wrap the object to be bound, whereby a binding structure is formed. The present invention is also useful for a wire harness in which the object to be bound is a covered electric wire.

  A laminated nonwoven fabric for a pipe-type covering material is manufactured by laminating the first fiber layer and the second fiber layer and mechanically intertwining these fibers. In this production method, it is desirable to orient the high heat-shrinkable fibers in a substantially constant direction in the plane direction, and in particular, when the laminated nonwoven fabric for pipe-type coating materials is a long sheet, the high heat-shrinkable fibers Is preferably arranged in the width direction of the long sheet. In the manufacturing method, the first and second fiber layers are mechanically entangled and then heated to a temperature at which the shrinkage of the highly heat-shrinkable fibers is developed, so that the laminated nonwoven fabric for pipe-type coating material curls, so that the pipe It is possible to manufacture a type covering material. The present invention also includes a bundling method in which a material to be bound is disposed on the second fiber layer side of the laminated nonwoven fabric for pipe-type covering material, and the laminated nonwoven fabric for pipe-type covering material is heated and curled.

  The laminated nonwoven fabric (sheet) for a pipe-type coating material according to the present invention is composed of a first fiber layer and a second fiber layer, and the fibers are mechanically entangled and bonded between the fibers. It is easy to handle and is not easily deformed. Since the heat shrinkage rate is greatly different between the first and second fiber layers, when heated, the fiber layer having a high heat shrinkage rate can be curled to form a pipe-type coating material. Therefore, it is possible to transport the sheet in the form before it is made into a pipe (for example, with the sheet cut to an appropriate size or with the sheet wound around a core material), which can increase the loading efficiency. It is. In the field, it is possible to easily obtain a pipe-like material having a desired diameter and length by heating.

FIG. 1 is a schematic perspective view showing an example of a laminated nonwoven fabric for pipe-type coating materials according to the present invention. FIG. 2 is a schematic perspective view showing an example of the pipe type covering material of the present invention.

1) Laminated nonwoven fabric for pipe-type coating materials FIG. 1 is a schematic perspective view showing an example of a laminated nonwoven fabric for pipe-type coating materials according to the present invention (hereinafter sometimes simply referred to as “laminated nonwoven fabric”). As shown in FIG. 1, the laminated nonwoven fabric is a laminate of a first fiber layer (nonwoven fabric, web) and a second fiber layer (nonwoven fabric, web) having different heat shrinkage rates. In the present invention, the heat shrinkage rate of the first fiber layer is small, and the heat shrinkage rate of the second fiber layer is set large. The direction of curling is determined by the difference in thermal shrinkage between the first and second fiber layers, and the laminated nonwoven fabric is uniformly curled. The cushioning property of the first fiber layer on the outside is effective as a protective material and a binding material.

More specifically, the heat shrinkage SHD _{1 at} a temperature of 150 ° C. of the first fiber layer is 5% or less, preferably 4% or less, more preferably 3% or less. Further, the lower limit of the heat shrinkage SHD ₁ is preferably 0% or more. If the heat shrinkage SHD ₁ is greater than 5%, the first fiber layer is also shrunk by heating, and the entire laminated nonwoven fabric is difficult to curl uniformly.

The heat shrinkage SHD _{2 at} a temperature of 150 ° C. of the second fiber layer is 15% or more, preferably 16% or more, more preferably 17% or more. Further, the upper limit of the heat shrinkage SHD ₂ is not particularly limited, but is, for example, 60% or less, preferably 50% or less, more preferably 45% or less. A thermal shrinkage SHD ₂ is less than 15%, be heated pipe type covering material laminated nonwoven is not preferable because the sheet is not curled sufficiently. If the heat shrinkage ratio SHD ₂ is greater than 60%, the second fiber layer may shrink excessively, and the cross-sectional shape of the pipe-type coating material is unlikely to be a circular shape or a C-shaped pipe shape, forming a pipe. It may be difficult to do.

The difference in heat shrinkage (SHD ₂ −SHD ₁ ) between the first and second fiber layers at a temperature of 150 ° C. is 10% or more, preferably 15% or more, and more preferably 20% or more. By setting the difference in thermal shrinkage to 10% or more, the laminated nonwoven fabric can be made into a pipe by thermal shrinkage. The difference (SHD ₂ −SHD ₁ ) is 50% or less, preferably 45% or less, more preferably 40% or less. By setting the difference in heat shrinkage to 50% or less, the cross-sectional shape of the pipe after heat shrinkage can be prevented from becoming uneven, and it is possible to form a circular or C-shaped pipe.

  The first fiber layer is mainly composed of high melting point fibers. By using the high melting point fiber, the shape stability of the first fiber layer is increased, and even when the laminated nonwoven fabric is heated, the cross section is prevented from being uneven and can be curled uniformly.

  A fiber having a melting point of 150 ° C. or higher is used as the high melting point fiber. Here, the melting point of 150 ° C. or higher means that the melting point does not exist below 150 ° C., and the present invention can use fibers having no melting point, that is, natural fibers such as cotton and wool.

  Specific examples of the high melting point fiber include thermoplastic fibers having a melting point of 150 ° C. or higher, natural fibers such as cotton and wool having no melting point, and glass fibers. As thermoplastic fibers having a melting point of 150 ° C or higher, general-purpose synthetic fibers such as polyester fibers, nylon fibers, acrylic fibers, and polypropylene fibers as well as high-performance fibers such as aramid fibers, polyimide fibers, and polyphenylene sulfide fibers can be used. is there. In applications where hydrophilicity is required, chemical fibers such as rayon fibers, cotton of natural fibers, and the like are suitable.

  Moreover, there is no restriction | limiting in particular in the fiber diameter of the high melting point fiber which can be used. However, if possible, the fibers are preferably 1 dtex to 30 dtex, more preferably 2 to 20 dtex, and even more preferably 3 to 10 dtex. Similarly, the fiber length of the high melting point fiber that can be used is not limited. However, if possible, the fiber length is preferably 20 to 100 mm, more preferably 30 to 70 mm, and still more preferably 40 to 60 mm. There is no restriction | limiting also in the cross-sectional shape of a high melting point fiber, A cross-section may be a round solid, and an irregular cross section and a hollow may be sufficient as it.

  The first fiber layer also includes a low melting point fiber (low melting point fiber A), which is mechanically entangled with the high melting point fiber. The low melting point fiber is a fiber having a melting point of less than 150 ° C, preferably less than 140 ° C, more preferably less than 130 ° C. When heated above the melting point of the low-melting fiber, the low-melting fiber is melted and cooled, thereby bonding other fibers constituting the first fiber layer. Furthermore, the low melting point fiber A may be heat-sealed not only with the fibers in the first fiber layer but also with the second fiber layer. Specifically, any fiber can be used as long as the melting point is less than 150 ° C. In particular, in the present invention, modified polyester fibers are preferably used, and other various modified nylon fibers, single fibers such as polypropylene-polyethylene fibers can be used, and core-sheath type or side-by-side type fibers can also be used. is there.

  The fiber diameter of the low melting point fiber A is not particularly limited. However, if possible, the fiber diameter is preferably 1 dtex to 30 dtex, more preferably 2 to 20 dtex, and still more preferably 3 to 10 dtex. Similarly, the fiber length of the low melting point fiber A is not limited. However, if possible, the fiber length is preferably 20 mm to 100 mm, more preferably 30 to 80 mm, and even more preferably 40 to 70 mm. The difference in fiber length between the high melting point fiber and the low melting point fiber A may be, for example, 30 mm or less, preferably 20 mm or less, and more preferably 10 mm or less. There is no restriction | limiting also in the cross-sectional shape of a low melting-point fiber, A cross section may be a round solid, and an irregular cross section and a hollow may be sufficient as it.

  The weight ratio of the high-melting fiber and the low-melting fiber A (the former / the latter) is 60/40 to 90/10, preferably 65/35 to 85/15, more preferably 70/30 to 80/20. It is. When the ratio of the high melting point fiber to the total of 100% by weight of the high melting point fiber and the low melting point fiber A is less than 60% by weight, various mechanical strengths are insufficient. If the blending ratio of the low melting point fiber A is less than 10% by weight, the first fiber layer cannot be sufficiently bonded and fixed, and the shape stability of the laminated nonwoven fabric or pipe is impaired. Moreover, since the whole 1st fiber layer will become hard when the compounding ratio of the low melting point fiber A is more than 40% by weight, handling after heating becomes difficult, which is not preferable.

Basis weight of the first fiber layer, 30 g / m ² or more and less than 350 g / m ^2, preferably from 50 to 300 g / m ^2, more preferably from 100 to 250 g / m ^2. If the basis weight is less than 30 g / m ² , the influence of the second fiber layer is strongly expressed, and the curling and curing of the laminated nonwoven fabric becomes intense, which is not suitable for practical use. If the basis weight is 350 g / m ² or more, depending on the amount of the second fiber layer, curling becomes weak even when heated, and a pipe-like product cannot be obtained.

  In addition, you may mix | blend another fiber and resin with the 1st fiber layer in the range in which this 1st fiber layer can satisfy the said specific heat shrinkage rate.

  The second fiber layer is mainly composed of highly heat-shrinkable fibers. By having the second fiber layer, when the laminated nonwoven fabric (sheet) is heated, it is possible to form a circular pipe-shaped product or a C-shaped pipe-shaped product.

  The high heat-shrinkable fiber is preferably used as long as the heat shrinkage rate at a temperature of 130 ° C. is 30% or more. More preferably, fibers that can shrink by 40% or more are suitable. The upper limit of the shrinkage rate is not particularly limited as long as technically possible, but is usually 80% or less at a temperature of 130 ° C.

  In the production of the second fiber layer, the high heat-shrinkable fibers are preferably oriented in a substantially constant direction within the plane direction. When the number of oriented fibers increases, shrinkage in the orientation direction becomes stronger when heated, and it becomes possible to produce a circular pipe-shaped product that shrinks more uniformly.

  As the high heat-shrinkable fibers, for example, known high heat-shrinkable fibers such as olefin resin fibers (ethylene-propylene random copolymer fibers, etc.), polyester resin fibers (modified polyester fibers, etc.) and polystyrene resin fibers can be used. is there.

  There is no restriction | limiting in particular in the fiber diameter of the said high heat-shrinkable fiber. However, if possible, the fibers are preferably 0.2 dtex to 20 dtex, more preferably 0.5 to 15 dtex, and still more preferably 1 to 10 dtex. There is no restriction | limiting also in the fiber length of a high heat-shrinkable fiber. However, if possible, the fibers are preferably 20 mm to 100 mm, more preferably 30 to 70 mm, and even more preferably 40 to 60 mm. There is no restriction | limiting also in the cross-sectional shape of a fiber, A cross section may be a round-shaped solid, and a deformed cross section and hollow may be sufficient.

  The second fiber layer also includes a low melting point fiber (low melting point fiber B), which is mechanically entangled with the high shrinkable fiber. When low melting point fibers are contained in the first fiber layer and the second fiber layer, the low melting point fibers are melted and solidified by heating (heating for curling, heating after curling, etc.), and the fibers are fixed. As a result, the pipe-type covering material is less likely to lose its shape. The details of the low melting point fiber B are the same as those of the low melting point fiber A. However, the low melting point fiber A and the low melting point fiber B may be the same or different. Note that the smaller the melting point difference between the low-melting fiber A and the low-melting fiber B, the more desirable, and this difference is, for example, 30 ° C. or less, preferably 10 ° C. or less, and more preferably 5 ° C. or less.

  The weight ratio (the former / the latter) of the high heat-shrinkable fiber and the low-melting fiber B is 30/70 to 95/5, preferably 40/60 to 90/10, more preferably 50/50 to 80 /. 20. When the ratio of the high heat-shrinkable fiber to the total of 100% by weight of the high heat-shrinkable fiber and the low-melting fiber B is less than 30% by weight, the expression of the heat shrinkage force becomes poor. On the other hand, when the ratio of the low melting point fibers is less than 5% by weight, the second fiber layer is not sufficiently bonded and solidified.

The basis weight of the second fiber layer is 50 to 500 g / m ² , preferably 100 to 450 g / m ² , and more preferably 150 to 400 g / m ² . If the basis weight is less than 50 g / m ^{2, the} cross section of the sheet after curling does not become circular or C-shaped, or even an arc, which is not preferable. On the other hand, if the basis weight exceeds 500 g / m ² , the influence of the second fiber layer is strongly developed, and the curling and curing of the laminated nonwoven fabric becomes intense, so that it is not suitable for practical use.

  In the second fiber layer, other fibers and resins may be blended within a range in which the second fiber layer can satisfy the specific heat shrinkage rate. In particular, in order to improve the shape stability and heat resistance of the second fiber layer, the high melting point fiber blended in the first fiber layer may be blended in the second fiber layer. The blending ratio of the high melting point fiber is, for example, about 40% by weight or less, preferably about 5 to 35% by weight, and more preferably about 10 to 30% by weight of the entire second fiber layer.

  The weight ratio (the former / the latter) of the first fiber layer and the second fiber layer is 70/30 to 15/85, preferably 65/35 to 20/80, and more preferably 60/40 to 30/70. When the ratio of the first fiber layer is more than 70% by weight, curling becomes difficult, and when the ratio is less than 15% by weight, the influence of the second fiber layer is more easily expressed, which is not preferable.

The area of the plane of use of the pipe-type laminated nonwoven fabric for coating is, for example, 10 cm ² or more, preferably 50 cm ² or more for small ones, 100 cm ² or more, preferably 200 cm ² or more, more preferably 300 cm ² or more for large ones. is there. When the area is too small, it is difficult to coat the object to be coated (protected object, object to be bound, etc.) even if the laminated nonwoven fabric is curled, which is not preferable.

  Each layer of the laminated nonwoven fabric may be flame retardant, water repellent, antibacterial and the like as necessary. In order to impart these functions, fibrous materials (flame retardant fibers, water-repellent fibers, antibacterial fibers, etc.) having these functions may be used in each layer, and each layer may be sprayed or treated with a chemical solution having each function. Coating may be performed, or a drug having each function may be kneaded into the high-melting fiber, low-melting fiber A, B, or high heat-shrinkable fiber.

  In the laminated nonwoven fabric for pipe-type coating of the present invention, a third layer may be laminated in addition to the first fiber layer and the second fiber layer described above. Examples of the third layer include an adhesive layer, an antistatic layer, a waterproof layer, and a protective layer. The third layer is located at any position of the laminated nonwoven fabric for pipe-type coating, such as the surface of the first fiber layer, between the first fiber layer and the second fiber layer, or the surface of the second fiber layer. Can also be laminated. The third layer is not limited to a single layer, and any number of layers may be stacked. Further, the third layer is not limited to the fiber layer, and may be a film layer, for example.

2) Pipe type covering material FIG. 2 is a schematic perspective view showing an example of the pipe type covering material of the present invention. This pipe type covering material is formed by heating the pipe type covering laminated nonwoven fabric of FIG. 1 and curling (incurling) the second fiber layer 2 inside and the first fiber layer 1 outside. . The cross-sectional shape of the pipe-type covering material is preferably circular or C-shaped, and a slit is formed in the axial direction of the pipe-type covering material. When curled to a circular shape or a C shape, various products and objects around us can be wrapped, and these can be protected or bound. For example, a pipe-type covering material may be used as a protective material for electric appliances, a heat insulating material such as a gas pipe or water supply. Moreover, if a to-be-bundled thing, such as an electric wire (especially covered electric wire), is used as a covering, a pipe type covering material can be suitably used as a binding material for a wire harness or the like. Further, if the object to be coated (particularly the object to be bound) is heated after being wrapped with the pipe-type laminated nonwoven fabric for covering, the laminated nonwoven fabric is formed so as to follow the shape of the object to be coated, and becomes a suitable coating material.

3) Manufacturing method The laminated nonwoven fabric for pipe-type coating is manufactured by laminating the first fiber layer and the second fiber layer having the above predetermined relationship, and then mechanically intertwining the fiber layers. Further, when the manufactured laminated nonwoven fabric for pipe type coating is heated, curl is generated with the second fiber layer inside, and a pipe type coating material is obtained.

  The pipe-type laminated nonwoven fabric for covering can be manufactured according to various known production methods. Therefore, as an example of a method for forming a nonwoven fabric layer, a case where a web is formed by a card method, then laminated by a cross wrapper, and then the web fibers are mechanically entangled (particularly by a needle punch method) is taken up. It explains from.

  When forming the first fiber layer by the needle punch method, for example, after measuring raw fibers such as high-melting fiber and low-melting fiber A, they are mixed together, and the fibers are sent out in a certain direction by a carding machine. Form the web. After the intermediate web is lapped, needle punching is performed to form a first fiber layer. On the other hand, in the second fiber layer, after the fibers constituting the layer are weighed, the fibers are mixed, and the fibers are sent out in a certain direction by a card machine to form an intermediate web. After lapping the intermediate web, needle punching is performed to form a second fiber layer. However, in the lapping step, it is an important and preferable aspect that the high heat-shrinkable fibers are superposed so that they are oriented in a certain direction in the plane direction as much as possible. Particularly in the manufacturing process, the second fiber layer is a long sheet, and the high heat-shrinkable fibers are preferably oriented in the width direction of the long sheet. It is preferable that the number of oriented fibers increases, because the shrinkage in the orientation direction becomes strong when heated, and it becomes easy to manufacture a uniformly contracted circular or C-type pipe covering material. For the wrapping, a cross wrapper or the like is preferably used.

  Each of the first fiber layer and the second fiber layer is usually rolled up. Then, the first fiber layer and the second fiber layer are overlapped while rewinding these rolls, and then needle punched. In this way, the first fiber layer and the second fiber layer are integrated by unwinding and superimposing the rolled up fiber layers, and delamination occurs when the fibers are mechanically intertwined. It becomes difficult to do.

  The web forming method and the web fiber bonding method are preferably the above dry / mechanical entanglement (particularly the needle punch method), but are not limited to this, and various known methods can be employed. In any case, it is preferable to orient the highly shrinkable fibers in a substantially constant direction (particularly in the width direction) in the plane direction.

  The laminated nonwoven fabric (sheet) formed as described above may be further heated and curled to form a pipe-type coating material. However, before or together with the curl, other fibers are melt-bonded with the low-melting fibers A and B. Further, fiber omission from a laminated nonwoven fabric (sheet) or a pipe obtained from the laminated nonwoven fabric (sheet) may be prevented. In this case, the pipe-type laminated nonwoven fabric may be heated at a temperature equal to or higher than the temperature at which the low melting point fibers A and B melt (for example, 70 ° C. or higher, more preferably 80 ° C. or higher) and 170 ° C. or lower.

  When other fibers are bonded with the low-melting fibers A and B before curling, the upper limit of the heating temperature is lower than the temperature at which the shrinkage of the high heat-shrinkable fibers is manifested. If the sheet heated in this temperature range is heated again to a high temperature (above the temperature at which the shrinkage of the highly heat-shrinkable fibers is manifested), the sheet curls and can be used as a pipe-type coating material.

  In the case where other fibers are bonded with the low-melting fibers A and B together with the curl, the lower limit of the heating temperature is a temperature at which the shrinkage of the high heat-shrinkable fiber is expressed, for example, 100 ° C. or higher, preferably 130 ° C. or higher, more preferably 140 ° C. or higher. When heated at this temperature, the high-shrinkable fibers contract and curl, and the low-melting fibers A and B can also melt and bond other fibers.

  The heating method is preferably hot air heating. The heating may be in a state where the pipe-type laminated nonwoven fabric for covering is long or cut into a predetermined size. If the laminated nonwoven fabric is in a long state, the laminated nonwoven fabric may be continuously passed using a hot air circulation dryer or the like. Moreover, if the laminated nonwoven fabric is cut, it can be heated using a hot air generator or a dryer. In particular, when the laminated nonwoven fabric is cut into a predetermined size, or the core material (paper tube etc.) is rolled up to the work site, and when trying to obtain a circular or C-shaped pipe, A small hot-air dryer is effective.

  In order to more appropriately manufacture the pipe-type coating material, when the laminated nonwoven fabric is heated, it may be heated while covering the laminated nonwoven fabric on a columnar or cylindrical material (such as a metal pipe) having a desired diameter. For example, if a long sheet-like laminated nonwoven fabric is passed through a hot air drier while being covered with a long columnar material or cylindrical material, a continuous pipe-like product made of fibers having a certain diameter is obtained. Moreover, it is possible to obtain a pipe-type coating material by heating the cut laminated nonwoven fabric while covering the columnar material or the cylindrical material.

Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited by the following examples, and can of course be implemented with appropriate modifications within a range that can be adapted to the above-described gist. Included in the range.
Evaluation of the laminated nonwoven fabric for pipe type coating obtained in Examples and Comparative Examples was performed as follows.

(1) Basis weight According to JIS L1913 6.2.

(2) Heat Shrinkage A 20 cm line was drawn on each of the nonwoven fabric (laminated nonwoven fabric) cut into 25 cm × 25 cm, and was left for 10 minutes in a hot-air circulating drier kept at a temperature of 150 ° C. and then taken out. At room temperature (about 21 ° C.), the length L (cm) of the previously drawn line was measured with JIS steel rule 1 grade, and the two heat shrinkage ratios were obtained according to the following formula, and the average value was calculated for the sample. It was set as the shrinkage rate.
Thermal contraction rate (%) = (20−L) / 20 × 100

(3) Cross-sectional shape after heating The cross-sectional shape of the sample used for the measurement of the heat shrinkage rate was determined by visual observation.

(4) Thermal contraction rate of fiber The thermal contraction rate at a temperature of 130 ° C. was determined according to JIS L1015 8.15b (dry thermal contraction rate).

Examples 1-4
80% by weight of a regular polyester fiber (high melting point fiber) having a melting point of 264 ° C., a fineness of 6.6 dtex, and a length of 51 mm, and a modified polyester fiber (low melting point fiber A) having a melting point of 110 ° C., a fineness of 4.4 dtex, and a length of 51 mm 20% by weight was weighed and blended, and the fibers were sent out in a certain direction by a card machine to form an intermediate web. The intermediate web was lapped with a cross wrapper, and then needle punching was performed with a needle number of 40 and a needle number of 180 n / cm ² and a needle depth of 14 mm to form web A. The basis weight of the web A was 200 g / m ² , and the thermal shrinkage rate at a temperature of 150 ° C. was 0%.

A predetermined amount (90% by weight (Example 1), 80% by weight) of polyethylene-polypropylene fiber (high heat shrinkable fiber; heat shrinkage rate 45% at 130 ° C.) having a melting point of 140 ° C., a fineness of 2.2 dtex, and a length of 51 mm (Example 2), 60% by weight (Example 3), 40% by weight (Example 4)), and a modified polyester fiber (low melting point fiber B) having a melting point of 110 ° C., a fineness of 4.4 dtex, and a length of 64 mm. Predetermined amounts (10% by weight (Example 1), 20% by weight (Example 2), 40% by weight (Example 3), 60% by weight (Example 4)) are weighed, blended, and then fibered using a card machine. Was sent out in a fixed direction to form an intermediate web, and this intermediate web was wrapped with a cross wrapper. In this lapping, the high heat-shrinkable fibers were arranged in the width direction of the intermediate web. Next, needle punching was performed with a needle number of 40 and needle punching under the conditions of a number of driven needles of 160 n / cm ² and a needle depth of 13 mm. The basis weight of the web B is 150 g / m ² , and the thermal shrinkage at a temperature of 150 ° C. is 42% (Example 1), 38% (Example 2), 28% (Example 3), and 18% (implemented), respectively. Example 4).

The web A and web B were laminated, and needle punching was performed twice under the conditions of a number of needles of needle number 40 and a number of driven needles of 160 n / cm ² and a needle depth of 13 mm, to obtain a laminated nonwoven fabric having a basis weight of 350 g / m ² . . The thermal shrinkage rates of the laminated nonwoven fabric at a temperature of 150 ° C. were 30% (Example 1), 28% (Example 2), 18% (Example 3), and 12% (Example 4), respectively. After cutting the laminated nonwoven fabric into 300 mm squares and leaving them in a hot-air circulating drier kept at a temperature of 150 ° C. for 2 minutes, a pipe-like product having a length of 295 mm having a circular cross-section of 90 mm in diameter is obtained. It was. The cross-sectional state after heating of the obtained laminated nonwoven fabric was a circular shape in Examples 1 to 3, and a C shape in Example 4.

  After slitting the laminated nonwoven fabric of Example 2 to a width of 160 mm and passing it through a small hot-air circulating dryer maintained at a temperature of 150 ° C. for 2 minutes, a pipe-like product having a circular cross section with a diameter of 50 mm Was obtained continuously.

Examples 5-8
According to Example 1, the optimum blending ratio of web A and web B was examined. 80% by weight of a regular polyester fiber (high melting point fiber) having a melting point of 264 ° C., a fineness of 6.6 dtex, and a length of 51 mm, and a modified polyester fiber (low melting point fiber A) having a melting point of 110 ° C., a fineness of 4.4 dtex, and a length of 51 mm 20% by weight was weighed and blended, and the fibers were sent out in a certain direction by a card machine to form an intermediate web. The intermediate web was lapped with a cross wrapper, and then needle punching was performed with a needle number of 40 and a needle number of 180 n / cm ² and a needle depth of 14 mm to form web A. The basis weight of the web A is 100 g / m ² (Example 5), 200 g / m ² (Example 6), 300 g / m ² (Example 7), 200 g / m ² (Example 8), and a temperature of 150 ° C. The heat shrinkage rate in each was 0%.

A predetermined amount (80% by weight (Examples 5 to 7)) of polyethylene-polypropylene fiber (high heat shrinkable fiber; heat shrinkage rate 45% at 130 ° C.) having a melting point of 140 ° C., a fineness of 2.2 dtex, and a length of 51 mm, 60 % By weight (Example 8)) and a predetermined amount of modified polyester fiber (low melting point fiber B) having a melting point of 110 ° C., a fineness of 4.4 dtex, and a length of 64 mm (20% by weight (Examples 5 to 7), 20% by weight) % (Example 8)) and, in Example 8, 20% by weight of regular polyester fiber (high melting point fiber) having a melting point of 264 ° C., a fineness of 6.6 decitex, and a length of 51 mm, and mixed, Then, the fibers were sent out in a certain direction to form an intermediate web, and this intermediate web was wrapped with a cross wrapper. In this lapping, the high heat-shrinkable fibers were arranged in the width direction of the intermediate web. Next, needle punching was performed with a needle number of 40 and needle punching under the conditions of a number of driven needles of 160 n / cm ² and a needle depth of 13 mm. The basis weight of the web B is 400 g / m ² (Example 5), 300 g / m ² (Example 6), 200 g / m ² (Example 7), 300 g / m ² (Example 8), and a temperature of 150 ° C. The thermal shrinkage percentages of were 37% (Example 5), 35% (Example 6), 34% (Example 7), and 25% (Example 8), respectively.

The web A and the web B were laminated, and needle punching was performed twice under the conditions of a number of needles of needle No. 40 and a needle number of 160 n / cm ² and a needle depth of 13 mm, to obtain a laminated nonwoven fabric having a basis weight of 500 g / m ² . . The thermal shrinkage rates of the laminated nonwoven fabric at a temperature of 150 ° C. were 33% (Example 5), 32% (Example 6), 30% (Example 7), and 29% (Example 8), respectively. After cutting the laminated nonwoven fabric into 300 mm squares, the laminate was left for 2 minutes in a hot-air circulating drier kept at a temperature of 150 ° C. and then taken out, and the cross-sectional shape was observed.

Comparative Examples 1-2
80% by weight of a regular polyester fiber (high melting point fiber) having a melting point of 264 ° C., a fineness of 6.6 dtex, and a length of 51 mm, and a modified polyester fiber (low melting point fiber A) having a melting point of 110 ° C., a fineness of 4.4 dtex, and a length of 51 mm 20% by weight was weighed and blended, and the fibers were sent out in a certain direction by a card machine to form an intermediate web. The intermediate web was lapped with a cross wrapper, and then needle punching was performed with a needle number of 40 and a needle number of 180 n / cm ² and a needle depth of 14 mm to form web A. The basis weight of the web A was 200 g / m ² , and the thermal shrinkage rate at a temperature of 150 ° C. was 0%.

A predetermined amount (100 wt% (Comparative Example 1), 20 wt%) of polyethylene-polypropylene fiber (high heat shrinkable fiber; heat shrinkage rate 45% at 130 ° C.) having a melting point of 140 ° C., a fineness of 2.2 dtex, and a length of 51 mm (Comparative Example 2)) and a predetermined amount (0 wt% (Comparative Example 1), 80 wt% (Comparative Example) of a modified polyester fiber (low melting fiber B) having a melting point of 110 ° C., a fineness of 4.4 dtex, and a length of 64 mm 2)) were weighed and blended, the fibers were sent out in a certain direction with a card machine to form an intermediate web, and this intermediate web was wrapped with a cross wrapper. Next, needle punching was performed with a needle number of 40 and needle punching under the conditions of a number of driven needles of 160 n / cm ² and a needle depth of 13 mm. The basis weight of the web B was 300 g / m ² , and the thermal shrinkage rates at a temperature of 150 ° C. were 65% (Comparative Example 1) and 66% (Comparative Example 2), respectively.

The web A and the web B were laminated, and needle punching was performed twice under the conditions of a number of needles of needle No. 40 and a needle number of 160 n / cm ² and a needle depth of 13 mm, to obtain a laminated nonwoven fabric having a basis weight of 500 g / m ² . . The thermal shrinkage of the laminated nonwoven fabric at a temperature of 150 ° C. was 37% (Comparative Example 1) and 4% (Comparative Example 2), respectively. When the laminated nonwoven fabric is cut into a 300 mm square and then left for 2 minutes in a hot-air circulating dryer maintained at a temperature of 150 ° C., the laminated nonwoven fabric in Comparative Example 1 has an uneven cross-sectional shape. The shape of the nonwoven fabric was an arc shape. Both of these shapes were difficult to say as stable pipes.

Comparative Example 3
80% by weight of a regular polyester fiber (high melting point fiber) having a melting point of 264 ° C., a fineness of 6.6 dtex, and a length of 51 mm, and a modified polyester fiber (low melting point fiber A) having a melting point of 110 ° C., a fineness of 4.4 dtex, and a length of 51 mm 20% by weight was weighed and blended, and the fibers were sent out in a certain direction by a card machine to form an intermediate web. The intermediate web was lapped with a cross wrapper, and then needle punching was performed with a needle number of 40 and a needle number of 180 n / cm ² and a needle depth of 14 mm to form web A. The basis weight of the web A was 400 g / m ² , and the thermal shrinkage rate at a temperature of 150 ° C. was 0%. Melting point 140 ° C., fineness 2.2 dtex, length 51 mm polyethylene-polypropylene fiber (high heat shrinkable fiber; heat shrinkage 45% at 130 ° C.) 80% by weight, melting point 110 ° C., fineness 4.4 dtex, long A modified polyester fiber having a thickness of 64 mm (low melting point fiber B) 20% by weight was weighed and blended, and the fiber was sent out in a certain direction by a card machine to form an intermediate web, and this intermediate web was wrapped with a cross wrapper. In this lapping, the high heat-shrinkable fibers were arranged in the width direction of the intermediate web. Next, needle punching was performed with a needle number of 40 and needle punching under the conditions of a number of driven needles of 160 n / cm ² and a needle depth of 13 mm. The basis weight of the web B was 100 g / m ² , and the thermal shrinkage rate at a temperature of 150 ° C. was 32%.

The web A and the web B were laminated, and needle punching was performed twice under the conditions of a number of needles of needle No. 40 and a needle number of 160 n / cm ² and a needle depth of 13 mm, to obtain a laminated nonwoven fabric having a basis weight of 500 g / m ² . . The heat shrinkage rate of the laminated nonwoven fabric at a temperature of 150 ° C. was 11%. When the laminated nonwoven fabric was cut into a 300 mm square and then left for 2 minutes in a hot-air circulating drier maintained at a temperature of 150 ° C., it was taken out and the sectional shape of the laminated nonwoven fabric became an arc shape, which was unsuitable as a pipe. .

Comparative Example 4
Melting point 140 ° C., fineness 2.2 dtex, length 51 mm polyethylene-polypropylene fiber (high heat shrinkable fiber; heat shrinkage 45% at 130 ° C.) 70% by weight, melting point 110 ° C., fineness 4.4 dtex, A modified polyester fiber having a length of 64 mm (low-melting fiber B) of 30% by weight was weighed and blended, and the intermediate web was formed by feeding the fiber in a certain direction with a card machine, and this intermediate web was wrapped with a cross wrapper. Needle punching was performed twice with a needle number of 40 and a needle depth of 160 n / cm ² and a needle depth of 13 mm, to obtain a laminated nonwoven fabric having a basis weight of 200 g / m ² . The heat shrinkage rate of this laminated nonwoven fabric at a temperature of 150 ° C. was 45%. However, the cross-sectional shape of the pipe-like material was irregular, and the surface was severely uneven, which did not withstand practical use.

The results of the above examples and comparative examples are summarized as shown in Table 1 below.

DESCRIPTION OF SYMBOLS 1 1st fiber layer 2 2nd fiber layer 3 Bundling thing

Claims (11)

A laminate of first and second fiber layers,
The first fiber layer is mechanically entangled with a high-melting fiber that is at least one selected from thermoplastic fibers having a melting point of 150 ° C. or higher, natural fibers, and glass fibers, and a low-melting fiber A having a melting point of less than 150 ° C. A non-woven fabric layer, the weight ratio of the high-melting fiber and the low-melting fiber A (the former / the latter) is 60/40 to 90/10, and the thermal shrinkage SHD _{1 at} a temperature of 150 ° C. is 5% And the basis weight is 30 g / m ² or more and less than 350 g / m ² ,
The second fiber layer is a non-woven fabric layer in which a high heat-shrinkable fiber capable of shrinking by 30% or more at a temperature of 130 ° C. and a low-melting fiber B having a melting point of less than 150 ° C. are mechanically entangled, and the high heat shrinkability The weight ratio of the fiber to the low-melting fiber B (the former / the latter) is 30/70 to 95/5, the thermal shrinkage SHD _{2 at} a temperature of 150 ° C. is 15% or more, and the basis weight is 50 to 500 g / m ²
The weight ratio of the first fiber layer to the second fiber layer (the former / the latter) is 70/30 to 15/85,
A laminated nonwoven fabric for pipe-type covering materials, wherein the difference in heat shrinkage (SHD ₂ -SHD ₁ ) at a temperature of 150 ° C. between the first and second fiber layers is 10 to 50%. The high heat shrinkable fibers, pipe type covering material laminated nonwoven fabric according to claim 1 which has been Oriented in the plane direction. Pipe type covering material laminated nonwoven fabric according to claim 1 or 2 plane product is 100 cm ² or more. It is obtained by curling the laminated nonwoven fabric for pipe type covering materials according to any one of claims 1 to 3, and is a circular pipe shape or a C type pipe shape, and a slit is provided in the axial direction of the pipe type covering material. Pipe type coating material that is formed.   A binding structure in which the pipe-type coating material according to claim 4 is curled so as to wrap the object to be bound.   The wire harness according to claim 5, wherein the object to be bound is a covered electric wire. A nonwoven fabric layer in which a high melting point fiber, which is at least one selected from thermoplastic fibers having a melting point of 150 ° C. or higher, natural fibers and glass fibers, and a low melting point fiber A having a melting point of less than 150 ° C. are mechanically entangled. The weight ratio of the high-melting fiber and the low-melting fiber A (the former / the latter) is 60/40 to 90/10, the thermal shrinkage SHD _{1 at} a temperature of 150 ° C. is 5% or less, and the basis weight is A first fiber layer of 30 g / m ² or more and less than 350 g / m ² ;
A non-woven fabric layer mechanically entangled with a high heat-shrinkable fiber capable of shrinking by 30% or more at a temperature of 130 ° C. and a low melting point fiber B having a melting point of less than 150 ° C., and the high heat-shrinkable fiber and the low melting point fiber B The weight ratio (the former / the latter) is 30/70 to 95/5, the thermal shrinkage SHD ₂ at a temperature of 150 ° C. is 15% or more, and the basis weight is 50 to 500 g / m ² . The weight ratio of the fiber layer to the second fiber layer (the former / the latter) is 70/30 to 15/85, and the difference between the heat shrinkage rates SHD ₁ and SHD ₂ (SHD ₂ −SHD ₁ ) = 10 Laminating a second fiber layer that can satisfy 50%,
A method for producing a laminated nonwoven fabric for a pipe-type coating material, wherein these fiber layers are mechanically entangled. Wherein the high heat-shrinkable fiber, pipe type method for producing a coating material for a laminated nonwoven fabric according to claim 7 obtained by Oriented in the plane direction.   The manufacturing method of the laminated nonwoven fabric for pipe type coating materials according to claim 7 or 8, wherein the laminated nonwoven fabric for pipe type coating materials is a long sheet, and the high heat-shrinkable fibers are arranged in a width direction of the long sheet.   In the manufacturing method of the laminated nonwoven fabric for pipe-type coating materials according to any one of claims 7 to 9, after the first and second fiber layers are mechanically entangled, the shrinkage of the high heat-shrinkable fiber is developed. A method of manufacturing a pipe-type coating material, which is heated to a temperature and curls the laminated nonwoven fabric for pipe-type coating materials.   The bundling method which arrange | positions a to-be-bound material to the 2nd fiber layer side of the laminated nonwoven fabric for pipe type coating materials in any one of Claims 1-3, and heats and curls the laminated nonwoven fabric for pipe type coating materials.