JPH0478742B2 - - Google Patents

Description

[Detailed description of the invention]

(a) <Technical field> The present invention provides a novel nonwoven fabric that is extremely suitable for use as an auxiliary base material for clothing interlining, synthetic leather base fabric, etc.
In particular, the present invention relates to a method of manufacturing a nonwoven fabric with excellent flexibility. More specifically, the present invention relates to a method for manufacturing a nonwoven fabric, characterized by using a pair of rolls: a metal roll having protrusions on its entire surface and an elastic roll having a smooth elastic body on its entire surface. (b) <Prior art> In recent years, nonwoven fabrics have been used in various fields.
As one of these, when used as an auxiliary base material such as interlining for clothing or synthetic leather base fabric, it is necessary to fully satisfy the following points. High strength Good moldability Good adaptability Although flexibility includes flexibility as one of its elements, the two are not the same. Good adaptability means that, for example, when a nonwoven fabric is used as an interlining for clothing, it not only naturally functions as an interlining, but also maintains the flexibility of the fiber itself, so it does not affect the clothing itself or the human body. It should adapt well to exercise and not give a feeling of being a foreign body. Furthermore, when used in synthetic leather, it not only functions as a natural leather substitute, but also has flexibility and good compatibility with other materials. Although some conventionally known nonwoven fabrics have been used as such auxiliary substrates, these have the following problems. ○ Needle-punched nonwoven fabric It has relatively good adaptability, but it has low strength and has a lot of fluff on the surface, which makes it easy to fall off, so it has poor moldability. ○B Nonwoven fabric completely fixed with adhesive It has good strength and moldability, but because it is fixed with adhesive, it has poor flexibility. ○C Nonwoven fabric partially fixed with adhesive or thermocompression bonding The adaptability is somewhat improved compared to ○B, but it is insufficient. In order to solve these problems with nonwoven fabrics, the present inventors attempted to improve adhesives, improve partial bonding methods, etc., but could not obtain satisfactory results. Therefore, we conducted further research including structural analysis of the nonwoven fabric itself, and finally completed the present invention. (c) <Object of the invention> That is, the object of the present invention is to provide a method for producing a nonwoven fabric that eliminates the above-mentioned drawbacks, has high strength, good moldability, and excellent flexibility. be. (d) <Structure of the Invention> The method for producing a nonwoven fabric according to the present invention is a nonwoven fabric in which partial joints are scattered over the entire surface, and a protrusion having a substantial surface area of 0.03 mm ² to 4 mm ² at the top is formed within 10 mm. A linear pressure of 5 kg/cm was applied between a pair of rolls, consisting of a metal roll with a spacing of
It is characterized by being allowed to pass under conditions of ~50Kg/cm and a surface velocity ratio of 0.5 to 0.95. (e) <Specific explanation of the structure of the invention> The present invention will be explained in detail below. The fibers used as the raw material for the nonwoven fabric used in the method of the present invention are not limited, and almost all fibers can be used. However, when partial bonding is performed by thermocompression bonding, thermoplastic synthetic fibers or a fiber mixed web containing thermoplastic synthetic fibers as a main component are used. Thermoplastic synthetic fibers include nylon 6, nylon 66, and nylon 6.
- Polyamide-based or copolyamide-based products such as 10, polyester-based or ether-based products such as polyethylene terephthalate, polyolefin-based products such as polyethylene and polypropylene, polyvinyl chloride, and polyvinylidene such as polyvinylidene chloride. Examples include fibers made of halide or copolymerized polyvinyl halide, and composite fibers made by blending or laminating these various polymers. Furthermore, two or more types of fibers constituting the web may be mixed. Cellulose fibers can also be used as mixing fibers, but the mixing ratio is 50%.
It is preferable not to exceed. Thermoplastic fibers do not need to be used when partial bonding is performed using adhesives. In the present invention, thermocompression bonding is more preferable in order to achieve the object. The denier of the fiber is
Generally, 0.5 to 10 deniers are used. Although both short fibers and long fibers can be used, long fibers are preferred in order to obtain a high-strength nonwoven fabric. The nonwoven fabric used in the method of the present invention has partially bonded portions scattered over the entire surface of the nonwoven fabric.
A partial bond is a point where the single fibers in that area are substantially bonded over a certain area of the surface of the nonwoven fabric, and at this point, the single fibers are similarly bonded to each other from the front side to the back side of the nonwoven fabric. combined. Single fibers are glued together, self-adhesive,
They are joined by fusion. FIG. 1a is a schematic surface view of a nonwoven fabric having partial joints, and FIG. 1b is a cross-sectional view. In Fig. 1, 3 is a nonwoven fabric, 1 is a partial joint,
2 is a non-bonding part. The pattern of this partial connection part can be set arbitrarily, and examples thereof include a staggered arrangement, a square arrangement, and the like. Further, various types of partial joints may be considered, such as those in which the partial joints are continuous and unbroken. Typical partial bonding methods include thermocompression bonding and adhesive bonding, but partial bonding by thermocompression bonding is best achieved by processing between hot plates with an uneven embossed pattern on the surface or between hot rolls. This is common, and one plane may be smooth. Moreover, one of the rolls may be made into a flexible roll if necessary. The conditions for thermocompression bonding must be determined appropriately depending on the fibers used, but it is necessary to ensure sufficient bonding so that the bonded parts will not separate during subsequent special processing. Therefore, although the temperature usually depends on the fiber, it is preferably determined in combination with the pressure to be applied within the range of 5 to 50°C below the melting point of the fiber. When an adhesive is used, a so-called gravure roll and printing method is used. The area ratio of the partially bonded portion to the surface of the nonwoven fabric is preferably in the range of 5 to 60%. As the area ratio decreases and as the distance between the partial joints increases, flexibility improves, but fuzz increases. The distance between the partial joints is preferably 0.3 mm or more, more preferably 0.5 to 10 mm. Next, this nonwoven fabric is passed through a device consisting of a metal roll having protrusions on its surface (hereinafter referred to as a protrusion roll) and an elastic roll having elasticity (hereinafter referred to as an elastic roll) with a difference in roll surface speed between the two rolls. This protrusion roll may be the same as the embossed roll in any pattern for providing partial bonding as described above. Therefore, the shape and arrangement of the projections of the projection roll can be arbitrarily selected, but the cross-sectional shape of the top of the projection may be any shape such as circular, oval, square, rectangular, or triangular, and the side shape of the top may also be selected. , may be either a flat or curved surface. However, in order to reduce damage to the fibers, it is preferable that the edges be edged to a depth of 0.05 Rmm or more. The effective surface area of the top of this protrusion is 0.03mm ²
to 4 mm ² , more preferably 0.1 mm ² to 2 mm ²
This range is necessary for appropriate flexibility processing. Protrusions with a substantial surface area of less than 0.03 mm ² will become pin-like and will seriously damage the fibers, while protrusions exceeding 4 mm ² will have an area that is too large and will cause uneven processing, making it necessary to carry out appropriate softening processing. I can't.
Furthermore, the distance between the protrusions (pitch) is 10 mm.
Hereinafter, it is necessary to preferably set the thickness to 1 to 5 mm in order to perform appropriate flexibility processing. This interval is 10
If it exceeds mm, sufficient machining will not be obtained and local machining unevenness will occur. This protruding roller is preferably made of hard steel in terms of its function and durability, and is preferably subjected to various hardening treatments such as chrome plating or surface nitriding. The elastic roll may be made of paper, fibrous felt, plastic, elastomer, rubber, etc., but durable rubber is most preferred. Specifically, they are polyurethane rubber and styrene-butadiene rubber. In addition to durability, it is also preferable to add auxiliary materials such as carbon black and zinc oxide to adjust hardness. In addition, hardness, which is one of the important factors for softening, is determined primarily by the material used, but it is also necessary to control the degree of crosslinking by adjusting the amount of the above-mentioned auxiliary materials added and, especially in the case of rubber, by increasing or decreasing the crosslinking agent. The desired hardness can also be achieved by The strength of this elastic roll needs to be 50° to 90°, more preferably 60° to 70°, in order to perform appropriate softening. When the hardness is less than 50°, the material used is too soft and has poor durability, making continuous operation difficult. On the other hand, hardness
If it exceeds 90°, the nip width with the protrusion cannot be widened,
The processing area is small and sufficient softening processing cannot be performed. Incidentally, the core of the elastic roll is made of metal in order to drive the roll and keep the linear pressure constant in the width direction, and only the processed surface is made of an elastic material. The thickness of the elastic material is not particularly limited, but from the viewpoint of durability and economy, it is 3 mm or more.
A range of 50mm is appropriate. The hardness measurement method is JIS-
Using a spring-type hardness tester standardized by 6301, read the scale of the pointer and determine the hardness. The surface smoothness of the elastic body becomes rough to the level of matte finish due to processing, so there is no need to limit the smoothness at the time of installation. Common sense dictates that it's "visually smooth"
It is acceptable as long as it is within the range of . Next, the device for setting the speed ratio between the rolls may use a gear as a driving means for each roll, may be a V-pulley or timing pulley type, or the gear may be a chain gear, and the device may be a gear for driving each roll. A system in which the rolls are driven in conjunction with each other by a chain may also be used. Of course, so that the speed ratio can be changed, the gears, pulleys, etc. at the end of the roll must be removable and replaceable with different numbers of teeth and outer diameters. The processing speed of non-woven fabrics varies depending on the non-woven fabric being processed and the desired degree of flexibility, but generally it is 1~
It is best to set it within the range of 300m/min. Furthermore, it is not essentially important which surface speed of the protruding roll or the elastic roll should be faster. The relative speed ratio is important and only increases or decreases the actual processing speed in production. In the present invention, the surface speed of the protruding roll is defined as the processing speed, and the value obtained by dividing the surface speed of the elastic roll by this speed is determined as the speed ratio. If this surface speed ratio exceeds 0.95, the soft processing will not be sufficient, and if it is less than 0.5, the nonwoven fabric will be severely damaged, which is unsuitable, and a surface speed ratio in the range of 0.5 to 0.95 is desirable. Furthermore, the processing pressure generated between the above-mentioned protruding roll and elastic roll can be adjusted using a fixed interval method in which one of the bearings of both rolls is micro-slided to set a constant surface interval, and a nonwoven fabric is inserted between them. Alternatively, it can be processed by a constant pressure method of pressing with spring force, air force, hydraulic pressure, spring or gravity. Compared to the constant-space method, the constant-pressure method is less affected by changes in the thickness of the treated object, and can cause less damage to the nonwoven fabric or roll. To be more specific, if the linear pressure is less than 5 kg/cm, the softening process will not be applied substantially, resulting in insufficient softening, whereas if the linear pressure exceeds 50 kg/cm, the nonwoven fabric will be seriously damaged. This may cause fuzzing or a decrease in strength. Therefore, a range of 5 to 50 kg/cm is effective. Also, with respect to the surface speed ratio, if it is 0.95 or more, machining will be insufficient, and if it is less than 0.5, damage will be severe and it will be unsuitable. Therefore, a range of 0.5 to 0.95 is valid. By using this method, the action of combing and loosening is performed locally on the nonwoven fabric, and a considerable amount of loose yarns and free loops are actively generated in the fibers between the partial joints, resulting in A nonwoven fabric is produced in which the single fibers connecting the partial bonds have a loose thread ratio of 20% or more and a surface loop napping rate of 20 threads/cm or more. The softened nonwoven fabric obtained by the present invention has a loose yarn ratio P (%) ≧
20, and the surface loop napping degree F (strands/cm)≧20 is satisfied at the same time. P is P=R/N×100 (N: number of single fibers existing between partial joints, R: single fibers existing between partial joints that have a slack of 10% or more with respect to the straight line distance) It is defined as the number of single fibers bent and relaxed. F indicates the average number of single loop yarns per unit width that protrude to the surface and become napped. In known products, P (%) is less than 20 (%) because there are few single fibers with slack of 10% or more between partial bonds, and there are few raised loops (F (fibers/cm)).
is less than 20 (lines/cm). On the other hand, the nonwoven fabric produced by the method of the present invention has a large number of single fibers with a slack of 10 (%) or more between the partially bonded parts, and P (%) of 20
(%) or more, and there are many loops with raised hair F
(lines/cm) is 20 (lines/cm) or more. By adopting such a structure, the nonwoven fabric obtained by the method of the present invention not only maintains strength, has less surface fuzz, improves moldability, but also maintains the flexibility of the fiber itself. Shows excellent adaptability. The difference in flexibility and strength retention between a conventional partially bonded nonwoven fabric and a nonwoven fabric produced by the method of the present invention is shown in FIG. 2 as a stress-elongation curve. is a conventional nonwoven fabric, and is a nonwoven fabric produced by the method of the present invention. According to this figure, the method of the present invention improves the initial tensile modulus to a very low level and also lowers the overall modulus of elasticity, resulting in a very flexible nonwoven fabric.
It is clear that there is little decrease in strength and that sufficient strength is maintained. Such an effect is caused by the stress-elongation characteristics of nonwoven fabric in the intermediate tensile modulus (intermediate modulus) when the tensile modulus at 3% elongation (3% modulus) is half the breaking strength. It becomes even more noticeable when it is 1.2 times or less. The reason why the method of the present invention exhibits such effects is considered to be as follows. That is, partial bonding by adhesive and heat has a non-negligible temporary bonding effect, setting effect, etc. on fibers other than the partially bonded portion of the web, and originally the web before being partially bonded is placed on a collection bed such as a mesh. When stacked, most of the single fibers are already laid laterally parallel to the mesh plane, and there is little freedom in the vertical direction, so the effect of fixing the fibers due to these bonds is greater than expected. This appears as hardness. If this effect is eliminated and the fibers between these bonds are given a sufficient degree of freedom, the strength and fluffiness will hardly change, and the flexibility of the entire nonwoven fabric will be greatly increased. Is possible. Moreover, if the degree of freedom extends to the surface and pops out as a free loop on the surface, the tactile texture is considered to exhibit exceptionally improved softness. Typical partial bonding methods include thermocompression bonding and adhesive bonding, but partial bonding by thermocompression bonding involves bonding between hot plates with uneven embossed patterns on their surfaces;
Alternatively, treatment is generally performed between heated rolls, and one plane may be smooth. Moreover, one of the rolls may be made into a flexible roll if necessary. The conditions for thermocompression bonding must be determined appropriately depending on the fibers used, but it is necessary to ensure sufficient bonding so that the bonded parts will not separate during subsequent special processing. Therefore,
Usually, the temperature depends on the fiber, but it is preferably determined in combination with the pressure applied within the range of 5°C to 50°C below the melting point of the fiber. When an adhesive is used, a so-called gravure roll and printing method is used. Next, this nonwoven fabric is passed through a device consisting of a metal roll having protrusions on its surface (hereinafter referred to as a protrusion roll) and an elastic roll having elasticity (hereinafter referred to as an elastic roll) with a difference in roll surface speed between the two rolls. This protrusion roll may be the same as the embossed roll in any pattern for providing partial bonding as described above. Therefore, the shape and arrangement of the projections of the projection roll can be arbitrarily selected, but the cross-sectional shape of the top of the projection may be any shape such as circular, oval, square, rectangular, or triangular, and the side shape of the top may also be selected. , may be either a flat or curved surface. However, in order to reduce damage to the fibers, it is preferable that the edges be edged to a depth of 0.05 ^R mm or more. The effective surface area of the top of this protrusion is 0.03mm ²
to 4 mm ² , more preferably 0.1 mm ² to 2 mm ²
This range is necessary for appropriate flexibility processing. Protrusions with a substantial surface area of less than 0.03 mm ² will become pin-like and will seriously damage the fibers, while protrusions exceeding 4 mm ² will have an area that is too large and will cause uneven processing, making it necessary to carry out appropriate softening processing. I can't.
Furthermore, the distance between the protrusions (pitch) is 10 mm.
Hereinafter, it is necessary to preferably set the thickness to 1 to 5 mm in order to perform appropriate flexibility processing. This interval is 10
If it exceeds mm, sufficient machining will not be obtained and local machining unevenness will occur. This protruding roller is preferably made of hard steel in terms of its function and durability, and is preferably subjected to various hardening treatments such as chrome plating or surface nitriding. The elastic roll may be made of paper, fibrous felt, plastic, elastomer, rubber, etc., but durable rubber is most preferred. Specifically, they are polyurethane rubber and styrene-butadiene rubber. In addition to durability, it is also preferable to add auxiliary materials such as carbon black and zinc oxide to adjust hardness. In addition, hardness, which is one of the important factors for softening, is determined primarily by the material used, but it is also necessary to control the degree of crosslinking by adjusting the amount of the above-mentioned auxiliary materials added and, especially in the case of rubber, by increasing or decreasing the crosslinking agent. The desired hardness can also be achieved by The strength of this elastic roll needs to be 50° to 90°, more preferably 60° to 70°, in order to perform appropriate softening. When the hardness is less than 50°, the material used is too soft and has poor durability, making continuous operation difficult. On the other hand, hardness
If it exceeds 90°, the nip width with the protrusion cannot be widened,
The processing area is small and sufficient softening processing cannot be performed. Note that the core of the elastic roll is made of metal in order to drive the roll and to maintain constant linear pressure in the width axis direction, and only the processed surface is made of an elastic material. The thickness of the elastic material is not particularly limited, but from the viewpoint of durability and economy, it is 3 mm.
A range of ~50mm is appropriate. Hardness measurement method is JIS
Using a spring-type hardness tester standardized by -6301, read the scale of the pointer and measure the hardness. The surface smoothness of the elastic body becomes rough to the level of satin due to processing, so there is no need to limit the smoothness at the time of installation. It may be within the range of "visually smooth" according to common sense. Next, the device for setting the speed ratio between the rolls may use a gear as a driving means for each roll, may be a V-pulley or timing pulley type, or the gear may be a chain gear, and the device may be a gear for driving each roll. A system in which the rolls are driven in conjunction with each other by a chain may also be used. Of course, so that the speed ratio can be changed, the gears, pulleys, etc. at the end of the roll must be removable and replaceable with different numbers of teeth and outer diameters. The processing speed of non-woven fabrics varies depending on the non-woven fabric being processed and the desired degree of flexibility, but generally it is 1~
It is best to set it within the range of 300m/min. Furthermore, it is not essentially important which surface speed of the protruding roll or the elastic roll should be faster. The relative speed ratio is important and only increases or decreases the actual processing speed in production. In the present invention, the surface speed of the protruding roll is defined as the processing speed, and the value obtained by dividing the surface speed of the elastic roll by this speed is determined as the speed ratio. If this surface speed ratio exceeds 0.95, the soft processing will not be sufficient, and if it is less than 0.5, the nonwoven fabric will be severely damaged, which is unsuitable, and a surface speed ratio in the range of 0.5 to 0.95 is desirable. Furthermore, the processing pressure generated between the above-mentioned protruding roll and elastic roll can be adjusted using a fixed interval method in which one of the bearings of both rolls is micro-slided to set a constant surface interval, and a nonwoven fabric is inserted between them. Alternatively, it can be processed by a constant pressure method of pressing with spring force, air force, hydraulic pressure, spring or gravity. Compared to the constant-space method, the constant-pressure method is less affected by changes in the thickness of the object to be treated, and can cause less damage to the nonwoven fabric and rolls. To be more specific, if the linear pressure is less than 5 kg/cm, the softening process will not be applied substantially, resulting in insufficient softening, whereas if the linear pressure exceeds 50 kg/cm, the nonwoven fabric will be seriously damaged. This may cause fuzzing or a decrease in strength. Therefore, a range of 5 to 50 kg/cm is effective. Also, with respect to the surface speed ratio, if it is 0.95 or more, machining will be insufficient, and if it is less than 0.5, damage will be severe and it will be unsuitable. Therefore, a range of 0.5 to 0.95 is valid. By using this method, the action of combing and loosening is performed locally on the nonwoven fabric, and a considerable amount of loose yarns and free loops are actively generated in the fibers between the partial joints, resulting in A nonwoven fabric is produced in which the single fibers connecting the partial bonds have a loose thread ratio of 20% or more and a surface loop napping rate of 20 threads/cm or more. As described above, the nonwoven fabric obtained by the method of the present invention not only has sufficient strength and good moldability, but also has
Because it exhibits the above-mentioned excellent adaptability, it has become possible to be applied to applications that could not be adequately achieved with conventional nonwoven fabrics or knitted fabrics. Examples include shoe base fabrics, clothing interlinings, synthetic leather base fabrics, and various interior materials for vehicles and others. The methods for measuring various characteristic values in the present invention are as follows. Loose thread ratio (P) Take an enlarged planar photograph at an appropriate magnification, e.g. 8x,
Set an arbitrary part in a square whose side is the pitch dimension of the pattern of the partial joint part, and for each fiber in that width, select a single yarn with a slack of 10% or more (relative to a straight line). It is calculated as the value (ratio) obtained by dividing the number of threads by the total number of single threads. As a general rule, the yarn length is measured on a photograph along the curve. In addition, since a circular arc is usually drawn, draw a straight line from the photo of the single fiber connecting both ends, and measure the perpendicular distance from the straight line to the apex of the circular arc at the center, which is further away from the straight line.
The judgment can be made by comparing it with that of a pre-calculated arc of yarn length 10% longer. In addition, when the basis weight of the nonwoven fabric is large and the number of fibers is too large, it is sufficient to further draw an arbitrary line within the set square frame, trace the fibers that are approximately perpendicular to the line, and measure the degree of relaxation. Generally, if a method is adopted in which at least N=20 or more are randomly sampled within one square frame, the loose thread rate will be determined almost accurately. That is, in the enlarged plane photograph of the nonwoven fabric surrounded by a square in FIG. 3, 1 is a partially bonded portion, and 2 is a single fiber in a non-bonded portion. Now draw an arbitrary line o, and randomly draw a fiber almost perpendicular to it, y ₁ y ₂ ...
...y _o Select and mark about 20 or more. Next, trace the trajectory of each single fiber one by one on a semi-transparent paper.
Trace and copy each line separately, and judge whether the thread is 10% or more loose with respect to the set field of view frame or the point entering and exiting the partial joint _{1 1} ... _{o o} at the height of the bulge H ₁ of the approximate arc . As shown by A _o B _o ,
When there are two or more circular arcs, it is sufficient to check each arc and determine the total length by approximate calculation. Surface loop napping degree (F) The measurement method for expressing the napping degree of loop-shaped single fibers per unit is to mark a 1 cm width of sample 4 and mark it on the fourth
Fold it in half as shown in the figure, magnify its tip with a microscope, and count the number of raised hairs 5 protruding from the surface over a 1 cm width. (One loop is counted as one.) Most measurements can be made by projecting light from the side. (Those that protrude will appear shiny.) If there is only a slight amount of protrusion, it is obvious when viewed diagonally or from the side that the upper part of the loop is more than three times the diameter of the single yarn than the horizontal line on the surface. Determined by distance. Once confirmed, surface bird-eye observation is enough to make a determination. Strength Measured according to JIS-L-1068 (slip method) and expressed directly per unit width and basis weight. (For directional materials, use the average value for vertical and horizontal directions.) 3% elastic modulus The 3% stress value of the stress-elongation curve obtained from strength measurement is calculated per unit elongation and width, and per basis weight. Indicated by the value of Intermediate modulus of elasticity The stress value at 1/2 elongation at break is expressed as a value per unit elongation and width, and per basis weight. Next, the present invention will be specifically explained with reference to Examples. (f) <Example> Example 1, Comparative Example 1 An uneven roll having a pattern made by heating a polyester long fiber web (single yarn 1 d, basis weight 30 g/m ² ) obtained by a spunbond method to 230°C. (emboss depth 0.4 mm) and a metal roll with a flat surface to obtain a partially thermocompressed nonwoven fabric. This non-woven fabric is then heated to the height of the protrusion at room temperature.
0.4mm, 3mm pitch, 0.2mm apex, ² protruding rolls with a circular pattern and hardness.
Linear pressure is applied between 70° butadiene rubber elastic rolls.
A nonwoven fabric of the present invention was obtained by performing a softening process at 15 kg/cm with a speed ratio of 0.8 between both rolls. The processing speed is 50 m/min. Next, Table 1 shows the differences in performance with known partially thermocompression bonded nonwoven fabrics. The nonwoven fabric obtained by the method of the present invention has almost no change in strength and fluff compared to known fabrics, and has a 3% modulus of elasticity, bending resistance, and surface texture.
As shown by the loose yarn rate and surface loop napping rate, it has excellent adaptability.

[Table] The elastic modulus ratio is shown as the ratio between the above 3% elastic modulus and the intermediate elastic modulus. The Γ bending strength was measured according to JIS-L-1085 (cantilever method). Surface texture judgment is ○...soft,
△...Slightly soft, ×...Hard. To remove fluff, use a Gakushin friction tester, use cloth as the friction element, and rub it 100 times with a load of 250g.
judge. Grade 5 shows no fluff, grade 4,
There is only a slight fluff. Grade 3 has noticeable scattered fluff. Grade 2 has noticeable fluff.
Grade 1 has a lot of fluff on the entire surface. Example 2, Comparative Example 2 Nylon-6 long fiber web obtained by spunbond method (single yarn 1.5d, basis weight 150g/m ² ) was 190
The process was carried out between a patterned uneven roll (emboss depth 0.8 mm) heated to 0.degree. C. and a metal roll with a flat surface to obtain a partially thermocompressed nonwoven fabric. This non-woven fabric was then heated to a protrusion height of 0.3 mm at room temperature.
Processing is performed by applying a linear pressure of 20 kg/cm and a speed ratio of both rolls of 0.7 between a protruding roll with a diagonal pattern of 0.4 mm apex arranged at a pitch ^{of 2} mm and an elastic roll made of urethane rubber with a hardness of 60°. A nonwoven fabric of the present invention was obtained. The processing speed is 30 m/min. Performance was then measured in the same manner as in Example 1. The results are shown in Table 2.

[Table] As a result, as in Example 1, a nonwoven fabric with excellent strength, moldability, and adaptability was obtained. In addition, as a comparative example, a nonwoven fabric whose entire surface was lightly thermocompressed as in Example 2 (at the same pressure and temperature) was used.
When a web (treated at 100°C) was passed between the protrusion roll and elastic roll in the same manner as above, the fibers were completely broken and returned to the original web, making it impossible to handle. As described above, it is clear that the nonwoven fabric of the present invention not only has sufficient strength but also has good flexibility due to the increased degree of freedom of the fibers in areas other than the areas where they are partially thermocompressed. be. Examples 3 to 5, Comparative Examples 3 to 4 When producing processed nonwoven fabrics under the same conditions using the same equipment as in Example 1, the linear pressure was set to 1 Kg/cm, 5 Kg/cm, and 15 Kg/cm.
cm, 50Kg/cm, and 70Kg/cm.
The performance of the obtained nonwoven fabric is shown in Table 3. As a result, it was found that a linear pressure in the range of 5Kg/cm to 50Kg/cm is effective.

[Table] * Overall evaluation: ○ Good, △ Fair, × Not possible Examples 6 to 8, Comparative Examples 5 to 7 A partially thermocompressed nonwoven fabric with a basis weight of 30 g/m ² similar to that in Example 1 was placed on the top of a protruding roll. change the surface area,
A linear pressure of 15 kg/cm was applied between a protruding roll with a pitch of 5 mm between the tops and an elastic roll made of butadiene rubber with a hardness of 70°C, and a speed ratio of 0.8 was applied to both rolls to soften the material. obtained a nonwoven fabric,
The results are shown in Table 4. From the results in Table 4, the effective surface area of the top is 0.03
If it is within the range of ^mm2 to ^4.00mm2 , it is the object of the present invention.
It has been found that flexible nonwoven fabrics are produced. On the other hand, if the surface area of the top is less than 0.03 mm ² , the nonwoven fabric becomes pin-shaped and is likely to be damaged, and if it exceeds 4 mm ² , the area to be pressed becomes large, resulting in uneven flexibility processing performance.

【table】

[Table] * Overall evaluation: ○ Good, △ Fair, × Poor Examples 9 to 11, Comparative Examples 8 to 9 The top surface area of the protruding roll was set to 0.20 ^mm2 , and the pitch between the tops was changed to The conditions were the same as in Example 6 to obtain a softened nonwoven fabric. The results are shown in Table 5. From Table 5, it was found that if the pitch was within 10 mm, the flexibility processing performance targeted by the present invention could be obtained. On the other hand, it was found that when the pitch exceeds 10 mm, the flexibility of the nonwoven fabric, which is the object of the present invention, cannot be obtained.

【table】

[Table] * Overall evaluation: ○ Good, △ Good, × Bad Examples 12 to 15, Comparative Examples 10 to 11 When making processed nonwoven fabric using the same equipment and under the same conditions as Example 2, only the material of the elastic roll was changed. The hardness was changed to 40°, 50°, 60°, 80°, 90°, and 95°. The performance of the obtained nonwoven fabric is shown in Table 6. As a result, it was found to be effective in the hardness range of 50° to 90°.

【table】

[Table] * Overall evaluation: ○ Good, △ Fair, × Poor Examples 16 to 19, Comparative Examples 12 to 13 Polyester composite fiber obtained by spunbond method (single yarn 5D, sheath-core type, sheath: isophthalic acid) A long fiber web made of polymerized polyester m/p 210°C, core: polyethylene terephthalate m/p 260°C) is rolled between an uneven roll with a textured pattern (emboss depth 0.3 mm) and a relatively smooth roll with silk joints on the surface. Both rolls were processed at a surface temperature of 200°C and bonded by thermocompression. (Weight: 100g/m ² ), subsequent processing is as follows:
Using the same protruding roll and elastic roll as in Example 1, the linear pressure was 20 kg/cm, the speed difference between both rolls was 1.0,
Machining was performed under six different conditions: 0.95, 0.8, 0.6, 0.5, and 0.3. The performance of the obtained nonwoven fabric is shown in Table 7. As a result, it was found that a speed ratio in the range of 0.5 to 0.95 is effective.

[Table] * Overall evaluation: ○ Good, △ Fair, × Poor
(G) <Effects of the Invention> As described above, by applying the treatment method according to the present invention to nonwoven fabrics, it is possible to create a nonwoven fabric that has greater strength, better moldability, and better adaptability than conventional treatment methods. Flexible processing can be performed. Therefore,
It is now possible to apply it to uses that could not be fully achieved with conventional nonwoven fabrics, such as shoe base fabrics, clothing interlinings, synthetic leather base fabrics, etc., and its industrial significance is great.

[Brief explanation of the drawing]

FIG. 1a is a surface view schematically showing a nonwoven fabric having a partially bonded portion, b is a sectional view thereof, and FIG. Diagram showing elongation curve, 3rd
The figure is a schematic diagram showing the method of measuring loose thread ratio, and Figure 4 is a
FIG. 2 is a schematic diagram showing a surface loop pilaster measurement method. 1: Partially bonded portion, 2: Non-bonded portion, 3: Nonwoven fabric,
4: Sample, 5: Napped, A: Conventional nonwoven fabric, B: Nonwoven fabric of the present invention.

Claims (1)

[Claims] 1. A metal roll made of a nonwoven fabric with partial bonds scattered over the entire surface, and a metal roll having protrusions with a substantial surface area of 0.03 mm ² to 4 mm ² on the entire surface at intervals of 10 mm or less, and a hardness of 50° to 90°. Between a pair of elastic rolls with a smooth elastic body of ゜ on the entire surface,
Linear pressure from 5Kg/cm to 50Kg/cm, surface velocity ratio from 0.5 to
A method for producing a nonwoven fabric characterized by passing the material under conditions of 0.95.