JPH05209352A - Production of laminated nonwoven fabric - Google Patents

Abstract

PURPOSE:To provide a process for producing a laminated nonwoven fabric having high bulkiness and good formation. CONSTITUTION:Filaments produced by a melt-spinning process are discharged from an air sucker while developing crimps on the filaments. The filaments are opened at the outlet of the air sucker and the crimped filaments are collected on a collection conveyor to obtain a bulky web layer. Separately, other filaments produced by a melt-spinning process are discharged from an air sucker without developing crimps. The crimp-free filaments are opened at the outlet of the air sucker and accumulated on the bulky web layer formed on the collection conveyor to obtain a flat web layer. The flat web layer is laminated to the bulky web layer simultaneously with the formation of the flat web layer to obtain a laminated web. The objective nonwoven fabric is produced by mutually bonding the filaments constituting the laminated web.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention laminates a bulky web layer composed of crimpable filaments and a flat web layer composed of non-crimpable filaments to form a bulky and textured fabric. The present invention relates to a method for producing a laminated nonwoven fabric excellent in heat resistance.

[0002]

2. Description of the Related Art At present, long-fiber nonwoven fabrics represented by spunbonded nonwoven fabrics are used in various fields of application. The spunbonded nonwoven fabric has an advantage that it is superior in tensile strength or high in productivity as compared with the short fiber nonwoven fabric obtained by the card method. However, on the other hand, it has a drawback that it is inferior in bulkiness as compared with the above-mentioned short fiber nonwoven fabric. For this reason, in the case of direct contact with human skin such as a surface material of a sanitary material, the usage amount thereof may be smaller than that of the short fiber non-woven fabric. However, since the spunbonded nonwoven fabric has high productivity, the cost can be reduced, and it is optimal for use in disposable applications such as surface materials for sanitary materials. Therefore, various techniques for producing a spunbonded nonwoven fabric having a high bulkiness have been adopted.

It is known that in order to impart bulkiness to a spunbond nonwoven fabric, it is effective to crimp the long fibers which are the constituent fibers. This is because the crimping of the long fibers increases the volume of the gap between the long fibers and improves the bulkiness. As a conventional technique, for example, a latent crimpable side-by-side composite continuous fiber or a latent crimpable eccentric core-sheath composite continuous fiber composed of two types of thermoplastic resins is opened and accumulated to form a nonwoven web. After that, the composite long fibers are shrunk, and crimps are expressed by utilizing the difference in shrinkage ratio between different types of thermoplastic resins, and spunbonded nonwoven fabrics having crimped long fibers as constituent fibers are known. (Japanese Patent Laid-Open No. 48-1471
Japanese Patent Laid-Open No. 63-282350). In addition, polyethylene terephthalate and a polyethylene terephthalate copolymer having an intrinsic viscosity different from that of polyethylene terephthalate are used as raw materials, and these two polyesters are spun using a side-by-side type composite spinning hole. A method is also known in which crimpable side-by-side type composite long fibers are formed and a nonwoven fabric is produced using the long fibers (Japanese Patent Laid-Open No. 2-182963).

However, each of the above techniques has the following drawbacks because it uses two types of thermoplastic resins. That is, when a long-fiber nonwoven fabric is manufactured, there are inevitably formed portions called ears having thin thickness and uneven texture at both ends thereof. These ears are cut and discarded during or after the production of the long-fiber nonwoven fabric, but they are generally recovered and reused from the viewpoint of effective utilization of raw materials. However, this ear has a drawback that it is difficult to reuse because the two kinds of thermoplastic resins are mixed in this ear. For example, there is a drawback that it is difficult to melt this to obtain long fibers.

For this reason, when one type of polymer is melt-spun from a spinneret having irregularly shaped spinning holes and then stretched and solidified, only one side surface of the long fiber is cooled to crystallize in the cooled portion. The degree of crystallinity is increased in the non-cooled part and the density is made different in the cross section of the long fiber, that is, the volume shrinkage ratio from the molten state to the solid state is made different. A spunbonded nonwoven fabric is also proposed in which the crimped filaments are opened after being crimped and then accumulated (Japanese Patent Laid-Open No. 1-148862).
Publication). However, this method avoids the above-mentioned drawbacks but introduces the following new drawbacks. That is, in this method, since the crimps are applied to the long fibers before the long fibers are opened and accumulated, the long fibers are easily entangled with each other at the time of opening, and the good fibers cannot be opened well. There was a drawback. If the opening of the long fibers becomes poor, when the long fibers are collected to obtain the nonwoven web, uniform accumulation becomes impossible, and only a nonwoven web having a poor texture is obtained. In particular, in the case of a thin non-woven web having a basis weight of 30 g / m ² or less, the poor texture is remarkable as compared with a thick non-woven web having a basis weight of 50 g / m ² or more.

[0006]

SUMMARY OF THE INVENTION Therefore, the present invention provides a nonwoven web which is bulky but has a poor texture by using long fibers in which crimps are developed before opening and accumulating the long fibers.
On the other hand, non-crimped long fibers are used to obtain another nonwoven web which is not bulky but has a good texture. By laminating these both nonwoven webs, the bulkiness and texture are good as a whole. It is intended to obtain such a laminated nonwoven fabric.

[0007]

Means for Solving the Problems That is, according to the present invention, after the long fibers are discharged from the air sucker, the crimps are immediately developed, the fibers are then opened, and then the long fibers are integrated to form crimpable long fibers. A step of obtaining a bulky web layer and discharging the long fibers from the air sucker, then opening the fibers without causing crimps, and then accumulating to obtain a flat web layer composed of non-crimped long fibers. The present invention relates to a method for producing a laminated non-woven fabric, which comprises: a step; and a step of laminating the bulky web layer and the flat web layer.

First, the step of obtaining the bulky web layer in the present invention will be described. The crimpable long fibers constituting the bulky web layer are those in which the long fibers discharged from the spinneret are introduced into the air sucker, stretched and solidified, and then discharged from the air sucker to immediately develop crimps. is there. As described above, as a method for immediately developing crimps after being discharged from the air sucker, the method described in the above-mentioned JP-A 1-148862 can be adopted. That is, when one type of polymer is used, and when it is spun and stretched and solidified, by giving a difference in the volumetric shrinkage ratio in the cross section of the long fiber, the long fiber is crimped before forming the nonwoven web. Any method can be adopted as long as it is a method of expressing. In other words, when two kinds of polymers are used, the heat shrinkage rate of each polymer is different, and therefore, when the nonwoven web is discharged from the air sucker, the nonwoven web is not crimped (latent crimp). After forming, heat may be applied to develop crimps, but when one type of polymer is used, since the heat shrinkage rates are the same, crimps develop after forming the nonwoven web. It cannot be done and the crimp must be developed before forming the nonwoven web.

In the present invention, it is preferable to employ the following method as a method of using one kind of polymer and immediately developing the crimp after discharging from the air sucker. That is, the fiber-forming thermoplastic resin as the first component is supplied to the spinneret 3, while the same mixture of the fiber-forming thermoplastic resin as the first component and the inorganic compound powder as the second component is spun into the spinneret 3. It is supplied to the spinneret 3, and the first component and the second component are separately discharged from the pair of holes 6, 6'of the side-by-side type composite spinning hole 5 provided in the spinneret, and immediately thereafter the first component and the second component are discharged. This is a method in which the second component is laminated and then introduced into the air sucker 4 while being stretched and solidified to obtain a side-by-side type composite long fiber, which is then discharged from the air sucker 4 to immediately develop crimps.

Now, the reason why crimps appear immediately after being discharged from the air sucker 4 in the above method will be described. First, in this method, the fiber-forming thermoplastic resin S ₁ (first component) is charged into the extruder 1 and melted at a predetermined temperature. On the other hand, the same mixture S ₂ (second component) of the fiber-forming thermoplastic resin S ₁ and the inorganic compound powder S ₃ is put into the extruder 2 and melted at a predetermined temperature. The first component S ₁ and the second component S ₂ respectively reach the spinneret 3 through the pipes. The spinneret 3 is provided with a side-by-side type composite spinning hole 5, through which the first component S ₁ and the second component S ₂ are separately discharged. For example, the first component S ₁ is discharged through the hole 6 and the second component S ₂ is discharged through the hole 6 ′. When discharged, they are in a molten state, and at this time, the first component S ₁ and the second component S ₂ are bonded together. After that, both S ₁ and S ₂ are stretched and solidified and introduced into the air sucker 4.

In the above manufacturing process, the first component S ₁ and the second component S ₂ are in a molten state when discharged from the spinneret 3 and in a solid state when introduced into the air sucker 4. .. Therefore, the crystallization of the first component S ₁ and the second component S ₂ occurs at a certain position between the spinneret 3 and the air sucker 4. However, the crystallinity of the first component S ₁ is different from that of the second component S ₂ . For example, if the crystallinity of the first component S ₁ is X ₁ and the crystallinity of the second component S ₂ is X ₂ , then X ₁ <X ₂ .
The reason for this is that the second component S ₂ contains an inorganic compound powder, and this inorganic compound powder functions as a crystal nucleating agent and promotes crystallization. Since the density increases as the crystallinity increases, let the density of the first component be ρ ₁ ,
If the density of the second component is ρ ₂ , then ρ ₁ <ρ ₂ .

As described above, the first component S ₁ and the second component S ₂ are separately discharged from the pair of holes 6, 6'of the side-by-side type composite spinning hole 5 provided in the spinneret 3. Immediately after being discharged, the first component S ₁ and the second component S ₂ are bonded and stretched and solidified to obtain a side-by-side type composite continuous fiber. At this time, both the first component S ₁ and the second component S ₂ are in a molten state at the time of discharging from the side-by-side type composite spinning hole 5, and at the time of being introduced into the air sucker 4, both resins are crystallized and both resins are melted. It becomes a solid state. However, as is clear from the above description, the crystallinity X ₁ of the first component S ₁ is smaller than the crystallinity X ₂ of the second component S ₂ . That is, the degree of crystallization of the first component S ₁ is smaller. When the degree of crystallization is small, the volumetric shrinkage ratio from the molten state to the solid state is small. That is, the volumetric shrinkage ratio of the first component S ₁ is V ₁
And the volumetric shrinkage of the second component S ₂ is V ₂ , V ₁ <
It becomes V ₂ . In this way, when the volume contraction rate differs between the components S ₁ and S _{2 of} the side-by-side type composite long fiber, crimping occurs with the position where the second component S ₂ having a large volume contraction is located inside. As described above, the crimpable continuous fibers are formed by using one kind of the fiber-forming thermoplastic resin. It should be noted that this crimp does not appear on the surface in the state where tension is applied to the side-by-side type composite continuous fiber, but appears when the tension is released.
Therefore, when the side-by-side type composite continuous fiber is discharged from the air sucker 4, the crimp is developed.
It should be noted that the first component contains a small amount of the inorganic compound powder, the second component contains a large amount of the inorganic compound powder, and the crystallinity of the second component is made larger than that of the first component. Although it is possible to develop crimp, it is not preferable to include an inorganic compound powder in both components because a difference in crystallinity does not occur so much and it becomes difficult to impart sufficient crimp to the long fibers.

As is clear from the above description, this crimpable continuous fiber is produced by adjusting the crystallinity of the second component, that is, by adjusting the content of the inorganic compound powder in the second component. The degree of crimp can be increased or decreased. In addition, the degree of crimp can be increased or decreased by adjusting the composite ratio of the first component and the second component in the composite long fiber. That is, the higher the composite ratio of the second component, the greater the degree of crimping, and the lower the composite ratio of the second component, the smaller the degree of crimping.

After the long fibers are discharged from the air sucker 4 as described above, crimps are immediately developed. Then, the crimped continuous fibers are opened. To open the crimpable filaments, a conventionally known fiber-spreading device may be used. For example, the crimpable filaments are frictionally charged to give the same charge, and the crimpable filaments are repelled with each other. It is sufficient to open the fiber by allowing it. However, this fiber-opening property is not good as described above, and there is a portion where the crimpable long fibers are entangled with each other. After the crimpable long fibers are opened, the crimpable long fibers are accumulated on a collecting conveyor or the like to obtain a bulky web layer.

[0015] for use in forming the crimped long fibers, as a fiber forming thermoplastic resin S ₁ fiber forming thermoplastic resin S ₁ and the second component S ₂ is the same thermoplastic resin Any material having a fiber-forming ability can be used. Typically, a polyolefin-based thermoplastic resin such as polyethylene, polypropylene, a copolymer thereof, or a mixture thereof is used.
Alternatively, polyethylene terephthalate, polyamide, a copolymer thereof, or a mixture thereof may be used. In the present invention, in particular, the melt flow rate (measured under JIS K 7210 Table 1, Condition 14) is 10 to 80.
Polypropylene of the order of magnitude is preferred, most preferably 30-
50 is good. This is because when such polypropylene is used, the crimpable continuous fibers can be favorably formed. When such a polypropylene is used, the melting temperature in the extruder 1 or 2 is 180
It is preferably set to 280 ° C. If the melting temperature is lower than 180 ° C or higher than 280 ° C, stable spinning of polypropylene tends to be difficult.

As the inorganic compound powder S _{3 in} the second component S ₂ , any one can be used as long as it functions as a crystal nucleating agent. Titanium dioxide is typically used. The maximum particle size of the inorganic compound powder S ₃ such as titanium dioxide is preferably 0.4 μm or less. Maximum particle size 0.4μ
If it exceeds m, the dispersibility of the inorganic compound powder S ₃ when mixed with the fiber-forming thermoplastic resin S ₁ tends to be poor, or the screen (filter) in the spinning pack tends to be clogged. The content ratio of the inorganic compound powder S ₃ in the second component S ₂ may be about 0.5% by weight. At this level, a sufficient difference in crystallinity with the first component S ₁ occurs, and a volume shrinkage ratio difference that causes crimping of the side-by-side type composite long fibers is provided between the molten state and the solid state. You can When the content ratio of the inorganic compound powder S ₃ exceeds 0.5% by weight, for example, about 1.0% by weight, the difference in volumetric shrinkage becomes large, and the crimp becomes too violent. The spreadability becomes extremely poor, and even when laminated with a flat web layer having a good texture, only a laminated web having a poor texture as a whole tends to be obtained.

When the first component S ₁ and the second component S ₂ are bonded together to obtain a side-by-side type composite long fiber,
The composite ratio of S ₁ and S ₂ is a matter that can be arbitrarily determined within the range where crimping occurs when forming long fibers. For example, when the content ratio of the inorganic compound powder S ₃ in the second component S ₂ is 0.5% by weight, the first component S ₁ and the second component S ₂
The composite ratio of is preferably about S ₂ : S ₁ = 1: 1 to 4. In addition, for example, the inorganic compound powder S ₃ in the second component S ₂
When the content ratio of S is 1.0 wt% and the composite ratio of the first component S ₁ and the second component S ₂ is S ₂ : S ₁ = 1: 1, the degree of crimping of the obtained long fiber becomes severe. A tendency arises. Therefore, in such a case, to reduce the degree of crimping,
The content ratio of the inorganic compound powder S ₃ in the second component S ₂ may be reduced, or the composite ratio of S ₂ may be reduced.

The present invention comprises a step of obtaining a flat web layer composed of non-crimpable continuous fibers, in addition to the step of obtaining a bulky web layer described above. The flat web layer can be obtained by discharging the long fibers from the air sucker, then opening the fibers without causing crimps, and accumulating the long fibers. That is, the flat web layer may be formed by a method of stretching and solidifying the long fibers without giving a difference in the volumetric shrinkage in the cross section of the long fibers, and opening and accumulating the long fibers, that is, a conventionally known method. is there. For example, a fiber-forming thermoplastic resin is supplied to a spinneret, and a fiber-forming thermoplastic resin is discharged from a normal spinning hole provided in the spinneret to obtain long fibers. It can be obtained by introducing it into air sucker while stretching and solidifying it with a uniform volume shrinkage, and opening and accumulating long fibers discharged from the air sucker. Here, the non-crimpable long fibers mean long fibers having substantially no crimp, and include long fibers having no crimps and long fibers having some crimps. To do. That is, even when the normal melt spinning method is adopted, the volume shrinkage ratio may accidentally differ in the transverse cross section of the long fiber, and in such a case, a long fiber having a slight crimp is obtained. It is sometimes done. As the fiber-forming thermoplastic resin used when forming the non-crimpable continuous fiber, various conventionally known ones such as polyethylene, polypropylene, polyester, polyamide are used. It is also possible to use a crystal nucleating agent such as an inorganic compound powder or a material containing other additives. In particular, it is preferable to use the same thermoplastic resin as the fiber-forming thermoplastic resin used when forming the crimped continuous fibers. This is because when the bulky web layer and the flat web layer are heat-sealed to each other, the affinity is improved and a laminated nonwoven fabric which is difficult to peel off is obtained.

The bulky web layer and the flat web layer obtained as described above are laminated. For example, the bulky web layer and the flat web layer may be prepared separately, and the both may be laminated, or while the non-crimpable continuous fibers are accumulated on the bulky web layer to form the flat web layer. Alternatively, the bulky web layer and the flat web layer may be laminated. Further, the flat web layer and the bulky web layer may be laminated while the crimped continuous fibers are accumulated on the flat web layer to form the bulky web layer. Further, the bulky web layer and the flat web layer may be laminated one by one to have a two-layer structure, or a flat web layer may be laminated between two bulky web layers or two flat web layers. A bulky web layer may be laminated between the layers to form a three-layer structure. Further, a plurality of bulky web layers and a plurality of flat web layers may be alternately laminated to form a multilayer structure.
The weight ratio of the bulky web layer and the flat web layer is a matter that can be arbitrarily determined, but in general, the bulky web layer: flat web layer = 1: 0.3 to 3 or so.

After the bulky web layer and the flat web layer are laminated to form a laminated web, the crimped continuous fibers, the non-crimped continuous fibers, and the crimped continuous fibers of each laminated web layer are laminated. The laminated non-woven fabric can be obtained by bonding the non-crimpable long fibers to each other by any conventionally known method. For example, a laminated web is introduced between each roll of a hot embossing device consisting of a heated concavo-convex roll and a smooth roll, the laminated web is partially thermocompressed by the convex portions of the concavo-convex roll, and crimped in this crimping area. It is possible to obtain a laminated non-woven fabric by melting or softening the elastic long fibers and the non-crimpable long fibers, and self-fusing and bonding the long fibers together.

The fineness of the crimped long fibers and the non-crimped long fibers in the present invention can be arbitrarily determined, but when the obtained laminated nonwoven fabric is used as a surface material for sanitary materials, About 5 denier is preferable. When the fineness is smaller than less than 1 denier, it tends to be difficult to produce the crimped continuous fiber. On the other hand, when the fineness is more than 5 denier, the obtained laminated nonwoven fabric has low flexibility or soft touch, and is not suitable for use as a surface material for sanitary materials. When the resulting laminated nonwoven fabric is used as a surface material for sanitary materials, it is preferable to have a two-layer structure of a bulky web layer and a flat web layer, and the weight ratio of the bulky web layer to the whole is 30 to. It is preferably 70% by weight. Furthermore, it is preferable to use the surface on which the flat web layer is located as the side that comes into contact with the skin. This is because the flat web layer is smoother and has a better texture. On the other hand, the surface of the bulky web layer is in contact with the absorbent body of the sanitary material, and the bulky web layer provides elasticity to the skin through the flat web layer. The use of the laminated nonwoven fabric obtained by the method according to the present invention is not limited to the above-mentioned surface material of sanitary material, and can be used for various conventionally known uses.

[0022]

EXAMPLES First, the method of measuring physical properties used in the examples will be clarified as follows. [Melt flow rate of fiber-forming thermoplastic resin] JIS
K 7210 Measured under the condition 14 in Table 1. [Crimp number of crimpable continuous fiber] The crimp number was measured according to the crimp number measuring method of JIS L 1074. [Unit Weight of Laminated Nonwoven Fabric] The weight (g) per 1 m ^{2 of the} laminated nonwoven fabric is shown. [Tensile Strength of Laminated Nonwoven Fabric] The tensile strength was measured by the Tensilon tensile test according to JIS L 1096, and expressed as the average value of the tensile strength in the longitudinal and transverse directions. [Bulkiness of laminated nonwoven fabric] Using a compression tester KES-FB3 manufactured by Kato Tech Co., Ltd., the thickness is A (mm) when the measurement load is 2 g / cm ² , and when the measurement load is 50 g / cm ² . When the thickness of B is (mm), Y = [(A−B) / A] × 10
Y represented by 0 was expressed as bulkiness (%).

EXAMPLE As a fiber-forming thermoplastic resin, a melt flow rate of 40 was used.
Of polypropylene was prepared. Then, this polypropylene (first component) was charged into the extruder 1 and melted at a temperature of 230 ° C. In addition, this extruder 95.5
% By weight and titanium dioxide (rutile type, average particle size 0.20 μm,
A mixture (second component) having a maximum particle size of 0.34 μm) and 0.5 wt% was charged and melted at a temperature of 230 ° C. And
Each component was supplied from the extruders 1 and 2 to the spinneret 3 by a gear pump. Here, the spinneret 3 is provided with several side-by-side type composite spinning holes 5 having 120 holes, and the temperature thereof is set to 230 ° C. Each component has a total discharge amount per single hole of the side-by-side type composite spinning hole 5
It was set to 1 g / min, and the composite ratio of the first component and the second component was set to second component: first component = 3: 7 (weight ratio).
The side-by-side type composite continuous fiber obtained as described above was introduced into the air sucker 4 and melt-spun at a speed of 4000 m / min. The resulting crimped filament had a fineness of 2.26 denier and a crimp number of 11/25 mm. And
This crimpable long fiber was opened by a fiber-opening device provided at the exit of the air sucker 4, and then collected on a collecting conveyor to form a bulky web layer having a basis weight of 12 g / m ² .

On the other hand, polypropylene having a melt flow rate of 40 was used as the fiber-forming thermoplastic resin, which was put into an extruder and melted at a temperature of 230 ° C. Then, it was supplied to the spinneret through a gear pump. This spinneret was equipped with several ordinary spinnerets having 120 holes, and the temperature was set to 230 ° C. The long fibers discharged so that the total discharge amount per single hole of the spinning hole was 1 g / min were introduced into air sucker and melt-spun at a speed of 4000 m / min. The fineness of the obtained non-crimpable filament is 2.23.
It was denier and the number of crimps was 4/25 mm. Then, the non-crimpable long fibers are opened by an opening device provided at the exit of the air sucker, and then accumulated on the bulky web layer placed on the collection conveyor to have a basis weight of 12 g / m 2. The flat web layer of ² was formed, and the bulky web layer and the flat web layer were laminated to obtain a laminated web.

This laminated web was introduced between the rolls of a hot embossing device having a heated concavo-convex roll on the upper stage and a smooth roll on the lower stage to perform partial thermocompression bonding.
At this time, the shape of the convex portion of the concave-convex roll is round, and the diameter is 0.
It was set to 3 mm. The heating temperature of the uneven roll was 140 ° C. The laminated non-woven fabric obtained as described above has a fusion area ratio (the ratio of the total area of the areas where the long fibers are self-fused to each other to the total area of the non-woven fabric) of 3%, and the texture is also good. It was good. The weight of this laminated non-woven fabric is 23.9g.
/ M ² , tensile strength 5.0 kg / 5 cm, bulkiness 6
It was 2%.

Comparative Example In the examples, a fibrous web having a basis weight of 24 g / m ² was obtained by forming only a flat web layer without forming a bulky web layer. At this time, the fineness of the obtained non-crimpable continuous fiber was 2.24 denier and the number of crimps was 4/25 mm. Then, this fibrous web was partially subjected to thermocompression bonding in the same manner as in Example to obtain a nonwoven fabric. The texture of this non-woven fabric was as good as the laminated non-woven fabric according to the example. Also,
The basis weight of this non-woven fabric is 24.1 g / m ² , and the tensile strength is 5.3.
It was kg / 5 cm and the bulkiness was 30%. As is clear from the above results, the laminated nonwoven fabric according to the example and the nonwoven fabric according to the comparative example show the same formation and tensile strength, but the laminated nonwoven fabric according to the example is superior in bulkiness. There is.

[0027]

The method for producing a laminated non-woven fabric according to the present invention comprises a bulky web layer obtained by opening and accumulating crimpable filaments and a flat web obtained by opening and accumulating non-crimpable filaments. And a step of laminating the layers. Therefore, even if the crimped continuous fibers are not opened easily and a bulky web layer having a good texture cannot be obtained, the non-crimped continuous fibers having good spreadability are spread and accumulated on the bulky web layer. Moreover, since the flat web layers having a uniform texture are laminated, the poor texture of the bulky web layer is hidden by the flat web layer. Therefore,
The effect that a laminated nonwoven fabric having a good texture as a whole can be obtained. Further, since the bulky web layer is composed of the crimpable long fibers, it is highly bulky. Therefore, the obtained laminated nonwoven fabric also has the effect of being highly bulky.

When the bulky web layer is obtained by the method of claim 2, the crimpable continuous fiber is not a side-by-side type composite continuous fiber composed of two kinds of components as in the conventional case, but is formed of a single component. In addition, the inorganic compound powder is contained in only one component. Therefore, the ears generated during the production process of the bulky web layer are composed of a mixture of a single component fiber-forming thermoplastic resin and an inorganic compound powder, as opposed to the conventional mixture of two fiber-forming thermoplastic resins. .. Therefore, the ear can be recovered during the production of the bulky web layer, and a desired amount of the inorganic compound powder can be additionally added to be reused as the mixture (second component) in the method according to claim 2. The effect is that it can be done.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an example of an apparatus for producing a crimpable continuous fiber in the present invention.

FIG. 2 is a diagram schematically showing a plan view of a side-by-side type composite spinning hole.

[Explanation of symbols]

 1 Extruder 2 Extruder 3 Spinneret 4 Air sucker 5 Side-by-side composite spinning hole 6 Side-by-side composite spinning hole One hole 6'Side-by-side composite spinning hole Another hole

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location D04H 3/10 C 7199-3B 3/16 7199-3B

Claims (4)

[Claims] 1. A step of discharging a long fiber from an air sucker, immediately developing a crimp, then opening the fiber, and then accumulating it to obtain a bulky web layer composed of a crimpable long fiber, After the fibers are discharged from the air sucker, the fibers are opened without causing the crimp to develop, and then the fibers are accumulated to obtain a flat web layer composed of non-crimpable long fibers, and the bulky web layer and the flat web layer. And a step of laminating a web layer. 2. A mixture of the same fiber-forming thermoplastic resin and inorganic compound powder as the first component, which is the second component, while the fiber-forming thermoplastic resin as the first component is supplied to the spinneret 3. Is supplied to the spinneret 3, and the pair of holes 6 of the side-by-side composite spinning hole 5 provided in the spinneret 6 are provided.
From 6 ', after separately ejecting the first component and the second component,
Immediately, the first component and the second component are bonded together and then introduced into the air sucker 4 while being stretched and solidified to obtain a side-by-side type composite long fiber, and then the air sucker 4
The method for producing a bulky web layer according to claim 1, wherein crimps are developed immediately after being discharged from the sheet. 3. The method for producing a bulky web layer according to claim 2, wherein an olefinic thermoplastic resin is used as the fiber-forming thermoplastic resin. 4. The method for producing a bulky web layer according to claim 2, wherein the inorganic compound powder is titanium dioxide having a maximum particle size of 0.4 μm or less.