JP3072952B2 - Nonwoven fabric, method for producing nonwoven fabric using the same, and interlining - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention has a
g / m ² or less, the present invention relates to an invention capable of obtaining a base material having a low basis weight such as not more than g / m ² , and having a very good texture and hand. A nonwoven fabric and a nonwoven fabric for easily obtaining such a base material The present invention relates to a method for producing an interlining used and an interlining obtained by the method.

[0002]

2. Description of the Related Art Conventional nonwoven interlinings for women's clothing and men's clothing are mainly made of synthetic fibers such as polyester fibers and nylon fibers. Interlining made of the former polyester fiber is generally used as a general-purpose product because it is harder and has a lower shrinkage ratio to heat and is less expensive than those made of the latter nylon fiber due to the properties of the material, and Interlining made of the latter nylon fiber is used mainly in the field of luxury goods because of its softness and high cost.

[0003] In such nonwoven fabric interlining,
As a matter of course, it changes with the change in the required characteristics of the clothing material of the object to be used, taking advantage of the characteristics of the surface material, especially its soft texture, in response to the trend of upgrading women's clothing and men's clothing. Adhesive interlining is required, and conventional adhesive liquid impregnation, drying and heat treatment processes are required.The production process is long and the quality obtained is hard. The use of the so-called thermal bond type interlining, which has a short manufacturing process that can only be fused and has a soft quality, is used because of its simple manufacturing process and stable quality and productivity. It is well known that the share is increasing. That is, it is well known that an interlining material that makes use of a softer hand is required by a thermal bond type interlining material that uses a fiber that can be heat-sealed as a constituent fiber of the nonwoven fabric for interlining material.

[0004] However, even with this thermal bond type interlining, although there is a further request to make use of the softer texture of the surface material, a satisfactory solution capable of responding to the request has not yet been proposed.

[0005] That is, in order to obtain an interlining that can be sufficiently adapted to a thin and soft surface cloth, even if the basis weight of the interlining is considered, at present, it is about 8 to 10 g / m ^2. Is the limit. That is, for example, when using a heat bonding fiber having a fineness of about 1.2 dr, an interlining (nonwoven fabric) having a basis weight of about 10 to ¹² g / m ² can be obtained, but if the basis weight is to be reduced below this, In the web forming process, formation unevenness occurs, the entanglement between the single fibers is reduced, the spread to the doffer is deteriorated, and the production itself becomes difficult. Even if it can be manufactured, it is not possible to obtain a web having a good feeling, and eventually, there is a limit to reducing the basis weight.

Further, for example, the fineness is set to 0.8 to 0.5 dr.
When using a heat-bonded fiber reduced to a degree, the basis weight is 8 to 1
Although an interlining (non-woven fabric) of about 0 g / m ² can be obtained, in this case, if the weight per unit area is reduced below this, in addition to the above-described problems, the fiber opening due to the fineness of the single fiber is further increased. Unevenness occurs frequently, and the crimping fastness is reduced, so that the cylinder passage property is extremely deteriorated. In this case as well, there is a limit to the reduction of the basis weight from the viewpoint of production and product quality.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention overcomes the prior art in which the production of such a kind of interlining is difficult and stable quality cannot be obtained. A softer and better textured interlining with a lower fabric weight, and a softer and better textured interlining with finer fibers are stable in production and on products. It is something to get.

[0008]

Means for Solving the Problems As a result of diligent studies on the above-mentioned problems, the present inventors have found that the object can be achieved by constructing the nonwoven fabric for interlining as follows. That is, the first invention of the present invention relates to a “sea-island structural fiber (a) in which the high-melting polymer is a sea component and the low-melting water-soluble polymer is an island component, and the whole is water-soluble and thermocompression-bondable.
And a fiber (b) other than the fiber (a) containing at least one other water-insoluble heat-meltable fiber, wherein the non-woven fabric is fused by thermocompression bonding. The fiber (a) is characterized in that the sea component of the fiber (a) is broken and the island component released on the fiber surface is fused to bond the fibers. Nonwoven fabric suitable for ". The first invention is based on the description that "the fiber (a) constituting the nonwoven fabric of the first invention has a sea component having a melting point of 1;
90 ° C. or higher polyvinyl alcohol polymer,
The island component is a water-soluble polymer having a melting point 20 ° C. or more lower than the melting point of the sea component, and the blend ratio of the sea and island components is 98 /
2 to 55/45 sea-island structural fiber with a strength of 3 g / dr
As described above, it is a water-soluble and thermocompression-bondable polyvinyl alcohol-based fiber having a water dissolution temperature of 5 to 99 ° C. ".

[0009] The third invention relates to a sea-island structural fiber (a) having a water-soluble and thermocompression-bondable whole, wherein the high-melting polymer is a sea component and the low-melting water-soluble polymer is an island component. The fiber (b) other than the fiber (a) containing the other water-insoluble heat-fusible fiber is mixed with the fiber (b) at a mixing ratio of 10/90.
混 95/5 to perform cotton blending and web formation, and further perform thermocompression bonding that partially breaks the sea component phase of the fiber (a) but does not destroy its fiber structure. To form an adhesive non-woven fabric, and thereafter, the non-woven fabric is washed with water to remove the fiber (a), and the fiber (b)
The third invention is a method for producing a nonwoven fabric suitable for an interlining, wherein the fiber (a) constituting the nonwoven fabric according to the third invention is a polyvinyl alcohol-based material whose sea component has a melting point of 190 ° C. or higher. A water-soluble polymer in which the island component has a melting point lower than the melting point of the sea component by at least 20 ° C. A water-soluble and thermocompression-bondable polyvinyl alcohol fiber having a dissolution temperature in water of 5 to 99 ° C as described above, and a thermocompression condition for forming the nonwoven fabric at a temperature of 80 to 230 ° C and a linear pressure of 1 kg / cm or more The surface pressure is 2 kg / cm ² or more, and the removal of the fiber (a) from the nonwoven fabric is water washing at a temperature of 5 to 100 ° C. ”. That is, according to the above invention, an excellent interlining material having an extremely low basis weight of less than 8 g / m ² , and more specifically, 5 g / m ² or less can be obtained.

[0010]

According to the present invention, in order to obtain a nonwoven fabric which is particularly suitable for an interlining having an extremely low basis weight, the web constituting the nonwoven fabric is produced from the beginning with the use of the desired low basis weight fiber. The fiber (a), which is heat-fusible and water-soluble to the fiber (b) containing the desired (finally remaining) heat-fusible fiber, is interposed between A web is manufactured (that is, in an easy-to-operate state), heat-fused into a bonded nonwoven fabric having excellent formation and strength, and the interposed water-soluble fiber (a) is washed with water. And finally a non-woven fabric having a low weight per unit weight, which is made of the fiber (b) bonded with the heat-fusible fiber, is adopted.
It overcomes the difficulties of producing low weight webs directly from low weight fibers. Furthermore, in the present invention, the water-soluble fiber (a) is mixed with a polyvinyl alcohol-based polymer having a high melting point and a water-soluble polymer having a low melting point or a low fusing temperature, and the former is a sea component and the latter is an island component. Fibers with a structure in which the island component is extruded to the fiber surface during heat fusion, resulting in a fiber with excellent heat fusion properties, and stable dimensions due to the sea component during heat fusion. It can maintain a high fiber strength and can easily obtain a high-strength bonded non-woven fabric with no dimensional change during thermal fusion, and can treat and handle the bonded non-woven fabric before washing with water. Becomes extremely easy. As described above, the present invention has opened the way to produce industrially an excellent interlining material having an extremely low basis weight of less than 8 g / m ² , or even 5 g / m ² or less, which has not been realized conventionally.

In the present invention, the water-soluble fiber (a) which is added in advance to the fiber (b) containing the heat-fusible fiber, which finally remains as an interlining component, and which is finally washed and removed is used. This is an important point of the invention, but it is essential that the fiber (a) be water-soluble,
It is necessary that the heat-fusing property with the fiber (b) is excellent, and furthermore, the strength and the dimensional stability are excellent even under high humidity, and the dimensional change also occurs during the thermocompression bonding for the heat-sealing. It is necessary to have a small and high strength.

Therefore, as such a fiber (a),
The sea component is a high-melting polymer, and the island component is a low-melting water-soluble polymer. The heat-fusible, low-melting water-soluble polymer forming islands near the surface layer is extruded onto the fiber surface, and is fused with other fibers (b) and the fibers of itself (a). Although high pressure-bonding properties can be ensured, and even though the whole is water-soluble, highly oriented and highly crystallized high-melting polymer forms a matrix phase. It has excellent strength and dimensional stability even underneath, and the matrix phase is not greatly affected even during thermocompression bonding, the dimensional change is small, and high strength can be obtained even after thermocompression, such a fiber Realize , It is the basic gist of the invention to be used.

[0013] As such a sea-island structure fiber, for example, a high melting point polymer is a polyvinyl alcohol-based polymer, a low melting point polymer is a water-soluble polymer, and a mixed solution or a mixed liquid of the two is used. We focused on the fact that the latter can be realized by a polyvinyl alcohol-based fiber obtained by solution spinning so as to be an island component. In this case, the melting point of the sea component PVA-based polymer serving as the matrix is 190 ° C. or higher, and the difference in melting point (ΔTm) from the sea component PVA-based polymer is 20 ° C. or lower as the island component water-soluble polymer. Is necessary, the blend ratio of the sea-island component is in the range of 98/2 to 55/45, the strength is 3 g / dr or more, and the dissolution temperature in water is 5 to 5.
Desirably, the fiber has a temperature of 99 ° C.

If the melting point of the PVA-based polymer serving as a matrix is less than 190 ° C., heat resistance and handleability under high humidity become insufficient, and it is not possible to obtain a fiber which can be used for the purpose of the present invention. . In addition, high strength fibers cannot be obtained. The melting point of the sea component PVA polymer is 200
It is more preferable that the temperature is not lower than ° C. The upper limit of the melting point of the sea component polymer is not particularly limited, but the melting point is preferably 230 ° C. or less from the viewpoint of hot water solubility and thermocompression bonding.
When the temperature is 25 ° C. or lower, the water dissolution temperature lowers, which tends to be more preferable.

Specific examples of the sea component PVA-based polymer include a polymerization degree of 500 to 18,000 and a saponification degree of 88 to 1
High saponification degree PVA of 00 mol%. Polymerization degree is 150
It is more preferable that the saponification degree is 0 to 4000 and the saponification degree is 93 to 99.5 mol% in terms of hot water solubility and thermocompression bonding. In addition, ethylene, allyl alcohol, itaconic acid, acrylic acid, maleic anhydride and its ring-opened product, arylsulfonic acid, fatty acid vinyl ester having 4 or more carbon atoms such as vinyl pivalate, vinylpyrrolidone and a part of the ionic group Further, PVA modified by a modifying unit such as a neutralized product is also included. The method for introducing the modifying unit is not particularly limited, whether it is a copolymerization or a post-reaction. The distribution of the denaturing units is not limited to random or block. When distributed in blocks, the crystallization inhibitory effect is small, and a high melting point can be maintained even when denatured more than random. By using a high-melting-point PVA-based polymer having a high saponification degree as a continuous phase, it is possible to obtain a performance close to that of a single fiber of a high-melting-point polymer. Sticking can be prevented.

As the island component polymer, a water-soluble polymer having a melting point difference (ΔTm) lower than that of the sea component PVA-based polymer by 20 ° C. or more is used. If ΔTm is less than 20 ° C., the thermocompression bonding temperature becomes too high, and the orientation and crystallinity of the PVA-based polymer as the sea component are easily broken during thermocompression bonding, and the shrinkage during thermocompression bonding is undesirably increased. In this specification,
Even if it is a water-soluble amorphous polymer having no melting point, the amorphous polymer chip is heated to a predetermined temperature, and 0.1 kg
The minimum temperature at which the chips fuse together when a pressure of / cm ² is applied for 10 minutes is defined as the fusion temperature, and this fusion temperature is included in the above melting point. That is, the water-soluble amorphous polymer whose fusion temperature is lower than the melting point of the sea component PVA-based polymer by 20 ° C. or more is included in the water-soluble polymer of the present invention, and can be effectively used as the island component water-soluble polymer. The ΔTm with the island component water-soluble polymer is more preferably 30 ° C or higher, and further preferably 50 ° C or higher. Further, if the low melting point polymer is present on the outermost surface of the fiber, the fiber tends to stick when the fiber is manufactured or the fiber is left under high humidity. From this viewpoint, it is necessary that the low melting point polymer is an island component.

Specific examples of the water-soluble polymer of the island component differ depending on the PVA-based polymer of the sea component, but include low saponification degree PVA, high ionic group-modified PVA, cellulose derivatives such as highly-modified carboxymethyl cellulose, alginic acid and chitosan. And water-soluble polymers such as polyvinylpyrrolidone, and modified acrylic polymers. In particular, low saponification degree PVA or allyl having a saponification degree of 50 to 92 mol% and a polymerization degree of 50 to 4000 in terms of handleability (particularly at high humidity), adhesion, performance reproducibility (stability) and cost. Alcohol, acrylic acid, methacrylic acid, itaconic acid, maleic anhydride and its ring-opened product, arylsulfonic acid, vinylpyrrolidone, and 3 to 10 mol% of the ionic groups and partially or completely neutralized modified units. % Modified PVA is preferred. There is no particular limitation on the method of introducing the modifying unit, whether copolymerization or post-reaction. There is no particular limitation on the distribution of denaturing units, whether random or block. When the saponification degree is 65 mol% or less, the water solubility at high temperatures is particularly reduced. Therefore, a PVA-based polymer combined with a small amount of modification with the above modification unit is useful as an island component in the present invention. Although there is no particular limitation on the degree of polymerization of the island component polymer, it is important that the island component does not contribute to the fiber strength and contributes to the adhesiveness. ~ 1000 is preferred.

The blend ratio of sea component / island component of the sea-island fiber is in the range of 98/2 to 55/45 by weight. If the high melting point PVA-based polymer of the sea component is less than 55%, high strength fibers cannot be obtained. The high melting point PVA-based polymer is 5
When the content is less than 5% and the content of the low-melting water-soluble polymer is more than 45%, the low-melting water-soluble polymer tends to become a sea component, which is not preferable in terms of sticking. On the other hand, if the content of the low-melting-point water-soluble polymer is less than 2%, it is impossible to obtain thermocompression bonding performance that can withstand practical use. From the balance between strength and thermocompression bonding, the sea / island blend ratio is more preferably from 95/5 to 60/40, and even more preferably from 92/8 to 70/30.

In the above sea-island fiber, the low-melting point polymer of the island component is not preferably present on the outermost surface of the fiber, but is preferably present near the outermost layer, and the island is 0.1 to 2 μm from the outermost surface. Preferably, the components are present. The minimum thickness of the sea component in the vicinity of the outermost layer is important in that the high-melting-point PVA-based polymer in the outermost layer is broken at the time of thermocompression bonding, and the low-melting water-saturable polymer of the island component is extruded to the surface to obtain an adhesive force. The island components may be distributed uniformly in the fiber cross-sectional direction, but are preferably distributed more concentrated on the surface side. The island component may be continuous in the fiber axis direction, but is not necessarily continuous, and may be spherical, intermittent, elongated rod-like or rugby ball-like. As described above, it is important that the island component is present near the outermost layer of the fiber, and is not necessarily limited to the number of the island components. Preferably, more preferably 50, even 20
More preferably, the number is 0 or more.

The strength of the fiber (a) is desirably 3 g / dr or more. When the fiber strength increases, the amount of the fiber (a) blended with the fiber (b) itself can be reduced, the production cost can be reduced, and the web production speed can be improved. Further, in the present invention, the fiber (a) is finally removed by washing with water, but if the dimensional stability is high under high humidity at the nonwoven fabric stage before washing with water, it is practically extremely strict in storage and handling. However, complicated management is required and a serious problem is caused. However, if the dimensional stability under high humidity is improved, the problem can be solved and a great merit can be obtained. Therefore, in view of the relationship between the degree of orientation and crystallinity of the sea component of the fiber (a) in this case, the strength of the fiber (a) is at least 3 g / dr and the dissolution temperature in water is 5 to 99 ° C. Proved to be effective. Further, if the fibers have such characteristics, the fibers (a) are dissolved without significant shrinkage during removal by washing with warm water, so that the form of the remaining nonwoven fabric is not adversely affected. From this point, it was found that it was preferable.

As the fiber (b) constituting the interlining finally left as an interlining, synthetic fibers such as nylon fiber, polyester fiber, polyethylene fiber and polypropylene fiber, rayon which are conventionally used for interlining, for example. ,
Any fibers such as cupra, polynosic, solvent-based cellulose fibers, cellulose fibers such as cotton, wool, and water-insoluble polyvinyl alcohol fibers (so-called vinylon fibers) can be used. However, in the present invention, when the fiber (a) is washed and removed from the nonwoven fabric composed of the fiber (a) and the fiber (b) to reduce the weight per unit area, the form of the remaining fiber (b) as the nonwoven fabric is stabilized. The fiber (b) must be a heat-fusible synthetic fiber that can be bonded by the thermocompression bonding itself, or a fiber containing at least a part of the heat-fusible fiber (mixed cotton). is necessary.

Examples of such heat-fusible fibers include:
Typically, for example, a polyester polymer having a melting point of 210 ° C. or more is disposed in the inner layer, and a melting point of 105 to 145 is disposed in the outer layer.
Core-sheath type composite thermoplastic synthetic fiber in which a thermoplastic polymer made of polyethylene, polypropylene, polyamide, polyester, or the like is disposed at a temperature of 80 ° C., but is not necessarily limited thereto.
Any fiber can be used as long as it can be fused and bonded between fibers by thermocompression bonding at a pressure of 2 cm / cm ² or more or a surface pressure of 2 kg / cm ² or more.

An example of a method for producing the fiber (a) will be described. The high-melting-point PVA-based polymer and the low-melting-point water-soluble polymer are dissolved in a solvent at a ratio of 98/2 to 55/45 to obtain a spinning dope. The solvent herein must be a solvent that dissolves at least the high-melting-point PVA-based polymer. It is more preferable that the solvent is a common solvent that also dissolves the low-melting water-soluble polymer. However, even if it is not necessarily dissolved, it can be used as long as it can be pulverized and dispersed so as to be dispersed to 10 μm or less in the high-melting PVA-based polymer solution. . Dispersion particle size is 5
It is preferably at most 1 μm, more preferably at most 1 μm. Even when dissolved in a common solvent of both polymers, a uniform transparent solution is not obtained depending on the compatibility of both polymers. Rather, in the form of a spinning stock solution, a high-melting-point PVA-based polymer becomes a polymer blend solution in which a low-melting-point water-soluble polymer is finely dispersed in a matrix phase (sea phase) and a low-melting water-soluble polymer is an island phase, resulting in a turbid homogeneous finely dispersed phase separation liquid. Is preferred. Needless to say, when the compatibility of both polymers is good, a uniform transparent solution is obtained, and at the time of fiberization, if a stock solution and spinning conditions are adopted so that the high melting point polymer becomes a sea component, a desired fiber can be produced.

Specific examples of the solvent include polar solvents such as dimethylsulfoxide (hereinafter abbreviated as DMSO), dimethylacetamide, N-methylpyrrolidone and dimethylimidazolidinone; polyhydric alcohols such as glycerin and ethylene glycol; nitric acid; Examples thereof include a strong acid such as sulfuric acid, a rhodane salt, a concentrated aqueous solution such as zinc chloride, and a mixture of these solvents. In particular, DMSO is preferred in terms of low-temperature solubility, low toxicity, low corrosion, and the like. Add both polymers to the solvent and stir and dissolve, or especially when it becomes a phase separation liquid, vigorously stir so that it disperses finely when dissolving and stir at low speed so that bubbles do not bite so that coagulation and sedimentation do not occur when leaving for defoaming Consideration such as continuing is preferable.

The resulting stock solution is subjected to dry spinning, dry-wet spinning or wet spinning. In dry spinning, the high-melting polymer becomes a matrix (sea component) while the solvent evaporates,
The spinning conditions are selected so that the low melting point polymer becomes an island, and the obtained fiber is wound. In dry-wet spinning, the stock solution is once discharged from a nozzle into an inert gas layer (for example, an air layer), then passed through a solidification solution, and solidification and extraction of the stock solution solvent are performed. If necessary, wet drawing and dry heat drawing are performed. Alms and winds. In wet spinning, an undiluted solution is discharged directly from a nozzle into a solidified liquid, solidified and extracted, and if necessary, wet-drawn and dry-heat drawn to take up. In any spinning method, it is necessary to consider the stock solution and spinning conditions so that the high melting point polymer becomes the sea component and the low melting point polymer becomes the island component. Specifically, it is effective to increase the blend ratio of the high melting point polymer to be a sea component. It is also effective to set the stock solution and spinning conditions in a direction in which phase separation is easy.

In order to increase the fiber strength to 3 g / dr or more,
In the solidification process, it is made into a uniform solidified yarn. To confirm that uniform solidification has been performed, the cross section of the drawn fiber is observed with an optical microscope, and when a fiber having a substantially circular cross section is obtained, it can be determined that uniform solidification has been performed. If a concentrated aqueous sodium sulfate solution, which is generally used for spinning PVA, is used as a solidification bath, the solidification becomes non-uniform, so that the cross-section becomes cocoon-shaped and stretching orientation cannot be performed sufficiently. Also, when boric acid is added to the stock solution and solidified in an alkaline dehydrated salt bath, partially saponified PVA is saponified during spinning, the melting point increases, and the water solubility decreases. On the other hand, alcohols such as methanol and ethanol, ketones such as acetone and methyl ethyl ketone, aliphatic esters such as methyl acetate and ethyl acetate, and high melting point PVA-based polymers serving as sea components such as mixed solvents of these and stock solutions. On the other hand, when an organic solvent having a solidifying ability is used for the solidifying bath, the solidification becomes uniform, so that the cross section becomes substantially circular, and sufficient orientation crystallization can be performed by subsequent wet stretching and dry heat stretching.

The cross-sectional shape of the fiber as referred to in the present invention is observed using a normal optical microscope. In order to obtain a more uniform gel, the solidification bath temperature should be 0-10.
It is preferable that the temperature be as low as ° C. Note that these solidifying baths do not necessarily have to have a solidifying ability with respect to the low-melting water-soluble polymer serving as an island component. Extremely low melting polymers can be spun even if they are soluble in the solidification bath. However, in this case, if the blending ratio of the high melting point polymer / the low melting point polymer is more than 6/4, it is not preferable because the low melting point polymer is eluted into the solidification bath or the fibers stick. More preferably, the low melting point polymer is less than 7/3. When the low-melting polymer is soluble in the solidification bath, the low-melting polymer tends to move toward the surface of the solidified itoshino together with the undiluted solvent during solidification, and tends to be more distributed in the surface layer than in the center of the fiber. An unexpectedly favorable tendency was found that even if the blending amount of the low melting point polymer was small, the decrease in thermocompression bonding property was small.

The itoshino which has come out of the solidification bath is subjected to a wet stretching bath consisting of a solidification solvent or a mixture of a solidification solvent and a stock solution for 2 to 8 hours.
Wet stretch twice. It is important to increase the magnification within the range where there is no fluff in order to suppress the sticking of the shinoshi. If the wet stretching is less than 2 times, sticking occurs, and if it exceeds 8 times, fluff is likely to appear. In order to increase the wet stretching ratio, it is also effective to raise the temperature of the wet stretching bath to near the boiling point. It is also effective to perform wet stretching in two or more stages.

The wet-stretched Ishino is brought into contact with an extraction bath mainly containing a solidifying solvent to extract the undiluted solvent from the Itoshino. This extraction preferably reduces the stock solution solvent content of Itoshino to 1% or less, preferably 0.1% or less. Such an extraction is achieved with a short residence time by continuously flowing the pure solidifying solvent in a countercurrent direction to the itoshino. The contact time is preferably at least 15 seconds, particularly preferably at least 20 seconds. The solidification solvent is preferably heated to increase the extraction rate and improve the extraction. Conventionally, generally, after wet drawing, a method of immediately drying without extracting and removing a stock solution solvent has been used.However, in the case of a fiber made of a polymer which is liable to cause agglomeration between single yarns, the above-described method is used. If only the conventional method is used, sticking between single yarns occurs during drying, and uneven shrinkage occurs during subsequent shrinking treatment, resulting in uneven shrinkage. Therefore, the solvent extraction treatment after wet stretching is an important step.

After the extraction, the dried itoshino is dried in a gas at 150 ° C. or lower. Attaching a hydrophobic oil such as a mineral oil, silicone, or fluorine before drying or shrinking to reduce shrinkage stress during drying is also effective in suppressing sticking.

The dry raw yarn is subjected to dry heat drawing at 100 to 220 ° C. 1 to 6 times, and in particular, oriented crystallization of the sea component PVA,
Preferably, a dry heat shrink treatment of 0 to 40% is then performed at 110 to 230 ° C. Although the dry heat yarn can be used as it is, it is also preferable to subject the dry heat yarn to a dry heat shrinkage treatment at 100 to 200 ° C and 0 to 20%.

The dry heat shrinkage treatment is not limited to one step, but if the shrinkage temperature is increased stepwise and shrunk in multiple steps, the shrinkage treatment can be performed at a higher temperature and a higher shrinkage rate without deteriorating the fiber and sticking. More complete strain relaxation becomes possible, and the maximum shrinkage ratio in water can be reduced. If the shrinkage rate is sufficiently large, even if the temperature is raised in water, the shrinkage does not occur at all, but rather may spontaneously elongate.

By the above, a fiber having a high strength of 3 g / dr or more can be obtained and a water-soluble fiber having a dissolution temperature in water of 5 to 99 ° C. can be formed. In addition, the fiber (a) having a small shrinkage upon dissolution in water can be obtained.

The fiber (a) obtained above is subjected to crimping and cutting to form staples,
And cotton. The mixing ratio of both fibers is preferably in a weight ratio of fiber (a) / fiber (b) = 10/90 to 95/5. The characteristic feature of the production method of the present invention is that it is less than 8 g / m ² or even 5 g / m ^2.
/ M ² or less in order to obtain a well-bonded interlining having a very low basis weight, if a web is formed from the beginning using a small amount of fiber, a good web cannot be formed. In a later stage, a water-soluble fiber that can be washed and removed is temporarily interposed to form a web with a fiber amount that facilitates the formation of the web, and thereafter, the water-soluble fiber is removed. If the ratio of the fiber (a) is less than 10/90 at this point, the characteristic point in the production method in the present invention cannot be exhibited, which is not preferable. If the ratio is more than 95/5, the amount of fibers to be washed and removed increases, which is not preferable in terms of the production method.

The mixed cotton fibers are spread by a conventional method, and are formed on a card or a random webber to form a web. The formed web is then subjected to thermocompression bonding on a calender roll or the like to obtain the nonwoven fabric for interlining described in the present invention. The formed web may be subjected to an entangling process such as a needle bunch or an air entangling before the thermocompression bonding.

The conditions for thermocompression bonding of the web with a calender roll are as follows: the temperature is 80 to 230 ° C., the linear pressure is 1 kg / cm or more, or the surface pressure is 2 kg / cm, in relation to the fiber characteristics of the fiber (a) to be used. It is preferably at least ² . These temperatures and pressures are the temperatures and pressures actually applied to the web, not the set temperatures and pressures. The actual temperature and pressure can be measured with a thermo label or a pressure indicator. When the compression temperature is less than 80 ° C., the linear pressure is less than 1 kg / cm, or the surface pressure is less than 2 kg / cm ² , the adhesive force by thermocompression is low,
Not practical. If the pressing temperature exceeds 230 ° C., the melting point of the PVA-based polymer as a sea component forming the matrix is exceeded, and the oriented and crystallized fiber structure is broken, and the fiber strength is reduced or shrinks. In view of the adhesiveness by thermocompression and the fiber strength and dimensional stability after compression, the temperature is 100
More preferably, the temperature is 130 to 190 ° C., the linear pressure is 5 to 50 kg / cm, or the surface pressure is 10 to 210 ° C., the linear pressure is ² to 200 kg / cm, or the surface pressure is 5 to 400 kg / cm ^2. More preferably, it is 100 kg / cm ² .

The nonwoven fabric (for interlining) obtained above is then subjected to a washing treatment to remove the fiber (a) from the nonwoven fabric.
Finally, a nonwoven fabric (interlining) made of the fiber (b) is formed. The treatment for removing the fiber (a) is performed by introducing the nonwoven fabric into a water bath at a temperature of 5 to 100 ° C. . As such a water bath, an ordinary dyeing machine such as a Wins system, a beam system, an Overmeyer system or the like is used. The water bath may be set at a temperature equal to or higher than the water dissolution temperature of the fiber (a). From the viewpoint of efficiency, it is necessary to keep the temperature of the water bath at a high temperature of 95 to 100 ° C. preferable. The bath ratio may be at least 1:30, but is preferably at least 1:50, and more preferably overflow from the viewpoint of efficiency. The dissolution time varies depending on the method, but is generally 20 to
It takes 180 minutes. After dissolution, wash thoroughly with overflowing with fresh water.

The nonwoven fabric for an interlining material of the present invention, the method for producing an interlining material using the nonwoven fabric, and the interlining material obtained from the production methods have been described. The most characteristic feature of the present invention is to obtain an interlining having a low basis weight of less than 8 g / m ^2. However, the method for producing a nonwoven fabric for an interlining according to the present invention and the interlining are also preferred. It is needless to say that the production method of the above does not exclude the interlining above the above-mentioned basis weight, as will be understood from the process.

The definition of the parameters used in this specification and the method of measuring the parameters are as follows. (1) Melting point: Mettler differential scanning calorimeter (DSC)
-20), 10 mg of the sample polymer was placed at 20 ° C. under nitrogen.
/ Min means a temperature at which an endothermic peak is exhibited when the temperature is increased at a rate of / min.

(2) Number of islands in the fiber: The fiber is embedded in a suitable resin such as paraffin, and the section is formed into an ultra-thin section by a microtome or the like. The number of islands is observed in a state where the island components are most easily observed using a microscope or a transmission electron microscope.

(3) Fiber strength: According to JISL-1015, a tensile test is performed at a single fiber strength of a test length of 20 mm and a tensile speed of 50% / min.

[0042]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In the examples,% is a value based on weight unless otherwise specified. Example 1 PVA having a polymerization degree of 1700 and a saponification degree of 98.5 mol% and a melting point of 225 ° C., a polymerization degree of 600 and a saponification degree of 7
15% and 5% of PVA with 3 mol% and melting point of 173 ° C.
Was mixed and stirred in DMSO at 90 ° C. under nitrogen so as to be dissolved. The blend ratio of the high melting point PVA-based polymer / low melting point water-soluble polymer was 75/25. The resulting blend solution was a semi-turbid solution having good spinnability, and did not tend to separate into two phases even after being left at 90 ° C. for 8 hours, and was a stable dispersion solution. This spinning dope was used with a hole diameter of 0.08 mm and a number of holes of 500.
Was wet-spun into a solidified solution of 70% methanol and 30% DMSO at 3 ° C. The obtained solidified itoshino was cloudy, and it was presumed that both PVAs were phase-separated. This solidified yarn is subjected to a 5.0-fold wet stretching, and is immersed in a methanol solution to extract and wash the solidified Itoshino DMSO.
A mineral oil-based oil agent was applied to obtain a 600 dr / 500 f filament. This filament had no sticking and the fusing temperature in water was 71 ° C. The single yarn strength is 9.3 g.
/ Dr. According to the cross-sectional observation of this fiber, the high melting point PVA having a saponification degree of 98.5 mol% is a sea component and the low melting point PVA having a saponification degree of 73 mol% is an island component. Individual fibers were present, and the cross-sectional shape of each fiber was found to be circular when examined with an optical microscope. This fiber was mechanically crimped, cut to 38 mm, and stapled. (This fiber is now referred to as fiber (A).)

The fiber (A) is 50% and the single fiber diameter is 1.
2dr, 38 mm long nylon fiber (melting point 190
° C) (this fiber is referred to as fiber (B)) at 50%.
And put it on a card, and the basis weight is 12 g / m.
^A web consisting of ² was produced. This web was guided between the embossed metal roll and the flat metal roll, and subjected to a thermocompression calender roll treatment at a temperature of 190 ° C., a linear pressure of 60 kg / cm and a treatment time of 1 second or less to obtain a bonded nonwoven fabric. The obtained nonwoven fabric was well adhered, the single yarn did not break even when rubbed by hand, and showed a breaking length of 5.3 km in length and 1.6 km in width. The bonding is performed by observing the nonwoven fabric with an electron microscope, the sea phase in the fiber (A) is partially broken, and the fibers are bonded together by island components extruded from the broken portion to the surface of the sea phase. ,
Adhesion between fibers due to fusion in the fiber (B) was mixed.

Next, this nonwoven fabric was put into warm water of 95 ° C. at a bath ratio of 1:50 using a beam dyeing machine, and was subjected to a dissolving and washing treatment for 60 minutes while overflowing, to reduce the basis weight, and then passed through a conveyor. It led to the drying process and dried. The obtained nonwoven fabric was excellent in texture and texture in which the entire nonwoven fabric was uniformly dissolved and removed. The measured basis weight was 6 g / m ² . When this nonwoven fabric was observed with a microscope, it was found that the above fiber (A) was not present on the nonwoven fabric, but only the fiber (B).
In the case of this example, this nonwoven fabric was finished into an adhesive interlining by attaching a polyamide-based thermoplastic adhesive to one surface in a dot-like manner. The dots were randomly arranged at 30 pieces per square inch, and the amount of the adhesive applied to the dots was 3 g / m ² . When this adhesive interlining was used as an interlining of a thin blouse for women, it became a blouse with excellent drape properties and a soft feel as compared with the conventional high-weight interlining.

Comparative Example 1 A fiber consisting of only the high-melting-point PVA component in Example 1 was produced under the same conditions as in Example 1 instead of the sea-island-type PVA fiber of Example 1. (Hereinafter, this fiber is referred to as fiber (C).) 70% of this fiber (C) is mixed with 30% of the fiber (B) used in Example 1 under the same conditions as in Example 1.
A web was formed on a card and subjected to a calender roll treatment by thermocompression bonding to obtain a bonded nonwoven fabric having a basis weight of 20 g / m ² . This nonwoven fabric can form a web well, but the nonwoven fabric obtained by thermocompression bonding has an insufficient overall adhesive force, is likely to cause a morphological change, and is difficult to handle. When this nonwoven fabric was observed for its bonding point with an electron microscope, the fiber (C)
No adhesion like the fiber (A) in Example 1 was observed, and only the fiber (B) was used, and it was found that the adhesion point was insufficient. That is, in the case of this example, the fiber (C) is not a fiber that bonds between the fibers, and therefore, the basis weight consisting of only the finally remaining fiber (B) is:
In the case of this example, if the weight is 6 g / m ² , the mixing ratio of the fiber (B) is too low. Therefore, the mixing ratio of the fiber (C) and the fiber (B) is, for example, 50/5.
If the ratio of the fiber (B) is increased to 0, the basis weight of only the finally remaining fiber (B) must be increased to 10 g / m ^2, and the initial basis weight is 6 g / m ^2. This makes it impossible to obtain a sufficient amount of nonwoven fabric.

[0046]

According to the present invention, in particular conventional interlining less than 8 g / m @ 2 which could not be obtained in the production process, the interlining of 5 g / m ² or less, such as very low basis weight, the formation and feeling good This is a method that can open the way to industrially stably produce the product, and can expand the area of the interlining.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI D06M 11/05 D06M 7/02 A (56) References JP-A-6-248548 (JP, A) (58) Fields investigated ( Int.Cl. ⁷ , DB name) D04H 1/00-18/00 D06M 1/00-11/18 D06M 16/00 D06M 19/00-23/18

Claims (6)

(57) [Claims] 1. A sea-island structural fiber (a) having a high-melting polymer as a sea component and a low-melting water-soluble polymer as an island component, which is entirely water-soluble and thermocompression-bondable, and at least one other water-insoluble heat A non-woven fabric comprising fibers (b) other than the fibers (a) containing fusible fibers, wherein the non-woven fabric is bonded by thermocompression bonding to the heat-fusible fibers. The non-woven fabric according to claim 1, wherein the fiber (a) has its sea component torn and the island component released on the fiber surface is fused to bond the fibers. 2. The fiber (a) whose sea component has a melting point of 190
Is a polyvinyl alcohol-based polymer having a melting point of 20 ° C. or more lower than the melting point of the sea component.
The nonwoven fabric according to claim 1, which is a water-soluble and thermocompression-bondable polyvinyl alcohol fiber having a strength of 3 g / dr or more and a dissolution temperature in water of 5 to 95 ° C, which is a 55/45 sea-island structure fiber. 3. A sea-island structural fiber (a) having a high-melting polymer as a sea component and a low-melting water-soluble polymer as an island component, the whole being water-soluble and thermocompressible, and at least one other water-insoluble heat. The fiber (b) other than the fiber (a) containing the fusible fiber is mixed with the fiber (b) at a mixing ratio of 10/90 to 95/5 to form a web, and the sea component phase of the fiber (a) is further removed. A thermocompression bonding that partially breaks but does not destroy the fiber structure is performed, the heat-fused fibers are melted to bond the fibers together to form an adhesive nonwoven fabric, and then the nonwoven fabric is washed with water to obtain the fibers (a). And a method for producing a nonwoven fabric comprising the fiber (b). 4. A method according to claim 1, wherein the sea component is a polyvinyl alcohol polymer having a melting point of 190 ° C. or higher, and the island component is a water-soluble polymer having a melting point lower than the melting point of the sea component by 20 ° C. or higher. Blend ratio of 98/2 to 55
/ 45 is a water-soluble and thermocompression-bondable polyvinyl alcohol-based fiber having a strength of 3 g / dr or more and a dissolution temperature in water of 5 to 99 ° C., and the thermocompression bonding conditions for forming the nonwoven fabric are temperature Is 80-230 ° C and linear pressure is 1kg
/ Cm or more, or a surface pressure of 2 kg / cm ² or more.
The method for producing a nonwoven fabric according to claim 3, wherein the washing is carried out at a temperature of from 100C to 100C. 5. An interlining made of a nonwoven fabric produced by the production method according to claim 3, wherein the basis weight is less than 8 g / m ² . 6. An interlining made of a nonwoven fabric produced by the production method according to claim 3, wherein the basis weight is 5 g / m ² or less.