JPH08260325A - Nonwoven fabric, wiping cloth made of the same and their production - Google Patents

Abstract

PURPOSE: To obtain nonwoven fabric having excellent shape stability and stain removing properties, suitably usable as a wiping cloth for lens for glasses. CONSTITUTION: Conjugate filament 1 is subjected to melt spinning. The filament 1 comprises a core component and plural shell components bonded to the outer peripheral part of the core component. Either the core component or the shell components have a lower melting point. The filament 1 is accumulated to form a yarn web 3, which is partially heated and pressurized to provide a great number of first fused zones in which the web is fused between the filaments 1. Then the web is subjected to filament splitting treatment and separated into the core component and the shell components of the filament 1 in the first fused zones to form ultrafine filaments composed of the shell components. A filament fleece 9 comprising the formed ultrafine filaments is partially heated and pressurized to give a great number of second fused zones in which the fleece is fused between the core components and the ultrafine filaments. In this way, nonwoven fabric suitable as a wiping cloth is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-woven fabric containing ultrafine fibers and a method for producing the same, and particularly to a nonwoven fabric which is excellent in stain removal performance due to ultrafine fibers and can be suitably used as a cloth for wiping lenses of eyeglasses and the like. It is about the method.

[0002]

2. Description of the Related Art Conventionally, nonwoven fabrics containing ultrafine fibers having a fineness of 1 denier or less have been widely used as wiping cloths for lenses such as glasses. Since such ultrafine fibers are difficult to be directly melt-spun to be manufactured, once the splittable conjugate fiber having a large fineness is melt-spun, and then the nonwoven sheet is prepared, and then the splittable conjugate fiber is split and split. Therefore, it is generally performed to generate ultrafine fibers. For example, after melt-spinning a splittable composite long fiber consisting of a core component and a plurality of bonding components joined to this core component, this is accumulated to form a fiber web, and then split fiber splitting treatment is performed on this fiber web. By separating the core component and the bonding component,
Ultrafine fibers composed of a joining component are produced. After that, by partially applying heat and pressure to this fiber fleece, a fusion-bonded area is provided, and a morphologically stabilized nonwoven fabric containing ultrafine fibers is manufactured (actually developed 4- No. 77863, Japanese Utility Model Laid-Open No. 4-78291).

According to this method, it is not necessary to directly melt-spin ultrafine fibers having fineness, but it is sufficient to melt-spin splittable conjugate fibers having large fineness, so that a nonwoven fabric containing ultrafine fibers can be obtained relatively easily. be able to. However,
In this method, the fiber web accumulating the splittable conjugate fibers is subjected to split splitting treatment to obtain a fiber fleece,
The following drawbacks occurred during the transportation of the fiber fleece before the fusion zone was provided to stabilize the shape. That is, when the fiber fleece is gripped while being pressed by the nip rolls and conveyed by the rotation of the nip rolls, the ultrafine fibers in the fiber fleece adhere to the surface of the nip roll, and the fiber fleece easily winds around the nip roll. The reason why the ultrafine fibers are likely to adhere to the surface of the nip roll is that the ultrafine fibers have a relatively large surface area and a relatively large electrostatic charge amount, or the adhesion area with the nip roll surface becomes large. Conceivable.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks, and the basic technical idea thereof is to preliminarily mutually partly divide a plurality of splittable composite long fibers in a fibrous web. After fusion fixing, even after the ultrafine fibers are produced by the split splitting treatment, the ultrafine fibers are held together by the fusion fixing, even if the ultrafine fibers adhere to the nip roll surface,
This is to prevent the nip roll from being wrapped around.

[0005]

The method for producing a nonwoven fabric according to the present invention, which embodies the above-mentioned basic technical idea, is as follows. That is, a composite long fiber composed of a core component and a plurality of outer shell components bonded to the outer peripheral portion of the core component and having a melting point lower than the melting point of the core component is accumulated to form a fiber web, The outer shell component is softened or melted by partially applying heat and pressure to the web, and a large number of first fusion zones in which the composite long fibers are fused to each other are provided, and then the split division is performed. A fiber fleece is produced by performing a fiber treatment to separate the core component and the outer shell component of the composite long fiber in a region other than the first fusion-bonded region, and generating ultrafine fibers composed of the outer shell component. And then by partially applying heat and pressure to the fiber fleece to soften or melt the ultrafine fibers to provide multiple second fusing zones where the core components are fused together. The present invention relates to a method for producing a characteristic nonwoven fabric.

Further, the melting points of the core component and the outer shell component are reversed, and a fiber web in which composite long fibers having a core component having a lower melting point than the outer shell component is accumulated is prepared, and the fiber web is partially heated. And, by applying pressure to soften or melt the core component, after providing a large number of first fusion zones where the composite long fibers are fused to each other, a split fiber treatment is applied, By separating the core component and the outer shell component of the composite long fiber in a region other than the one fusion-bonded region to produce ultrafine fibers composed of the outer shell component to form a fiber fleece, and then to the fiber fleece. A method for producing a non-woven fabric, characterized in that the core component is softened or melted by partially applying heat and pressure, and a large number of second fusion zones in which the ultrafine fibers are fused to each other are provided. It is about.

The nonwoven fabric according to the present invention obtained on the basis of the above-mentioned basic technical idea is as follows. That is, a nonwoven fabric formed by using a composite long fiber composed of a core component and a plurality of outer shell components bonded to the outer peripheral portion of the core component and having a melting point lower than the melting point of the core component. The outer shell component comprises a plurality of first fusion zones and a plurality of second fusion zones, wherein the first fusion zones are bonded to the core component between the composite long fibers. Are fused and formed by softening or melting of the core component and the outer shell component in the composite continuous fiber in the second fusion zone, and the core component and the outer shell component are separated from each other. The outer shell component is fused and formed by softening or melting, and in the region outside the first fusion zone and the second fusion zone, the core component and the outer shell in the composite long fiber are formed. The present invention relates to a non-woven fabric characterized in that ultrafine fibers composed of the outer shell component are produced by separating the components.

The nonwoven fabric according to the present invention obtained by reversing the melting points of the core component and the outer shell component is as follows. That is, a nonwoven fabric formed by using a composite long fiber composed of a core component and a plurality of outer shell components bonded to the outer peripheral portion of the core component and having a melting point higher than the melting point of the core component,
The non-woven fabric comprises a plurality of first fusion zones and a plurality of second fusion zones, wherein the first fusion zones are fused between the composite long fibers by softening or melting the core component. The second fusion-bonded area is separated from the core component and the outer shell component in the composite continuous fiber, and the outer shell component is separated from each other.
The core component is formed by being fused by softening or melting of the core component, and in the region outside the first fusion zone and the second fusion zone, the core component in the composite long fiber and the outer shell The present invention relates to a non-woven fabric characterized in that ultrafine fibers composed of the outer shell component are generated by separating the components.

First, the composite long fibers used in the present invention will be described. This composite long fiber is composed of a core component and a plurality of outer shell components bonded to the outer peripheral portion of the core component. Specifically, it is as shown in FIGS. 1 to 4 show an example of a cross section of a composite continuous fiber used in the present invention, which shows a core component (A).
And a plurality of outer shell components (B) joined to the outer peripheral portion of the core component (A). Outer shell component (B)
There are five in the drawing, but a plurality of two or more may exist. Particularly, in the present invention, it is preferable to use the composite long fibers having 5 to 8 outer shell components (B). The outer shell component (B) is joined to the outer peripheral portion of the core component (A) so as to be easily separated from the core component (A) by the split splitting treatment.

In order to facilitate the separation of the core component (A) and the outer shell component (B) of the composite long fiber, the most preferable structure is that both components (A) and (B) have the following relationship. Is when. This point will be described based on FIGS. 5 and 6 which schematically show the cross section of the composite continuous fiber.
First, a plurality of convex lens-shaped outer shell components (B) are joined to the outer peripheral portion of one core component (A). Furthermore, the weight ratio of the outer shell component (B) is 30 to 70 relative to the total weight.
% By weight. The radius of the circumscribed circle of the core component (A) is R ₀ , the radius of the circumscribed circle of the outer shell component (B) is R _1, and the outer shell component (B) having a convex lens shape is in contact with the core component (A). The radius of curvature of the arc is R ₂ , the arc length of this arc is L,
This is a case where the thickness of the convex lens-shaped outer shell component (B) is H, and there is a relationship that satisfies the following expressions (1) to (3). Note R ₁ / R ₀ > 1 (1) R ₂ / R ₀ ≧ 1 (2) L / H ≧ 1 (3)

The melting point of the outer shell component (B) is lower than that of the core component (A). This is because in the present invention, the outer shell component (B) which has not been separated from the core component (A) is used as a fusion component by softening or melting, and further the outer shell component (B) separated from the core component (A) ( This is because B) is softened or melted and used as a fusion component. Any combination of the core component (A) and the outer shell component (B) may be used as long as the melting point of the outer shell component (B) is lower. In the present invention, as a particularly preferred combination, a polyester-based polymer such as polyethylene terephthalate is used as the core component (A), and a polyolefin-based polymer such as polyethylene or polypropylene is used as the outer shell component (B). A combination in which a polyester polymer is used as (A) and a polyamide polymer such as nylon 6 or nylon 66 is used as the outer shell component (B) is preferable. In these cases,
The melting point of the polyester polymer is around 260 ° C., the melting point of the polyolefin polymer is around 130 ° C., and the melting point of the outer shell component (B) is lower. Further, the melting point of the polyamide-based polymer is around 200 to 260 ° C.,
In this case, there may be no difference from the melting point of the core component (A). In such a case, if the wet heat is applied instead of the dry heat, the melting point of the polyamide polymer is lowered, so that the melting point of the outer shell component (B) becomes lower.

Further, in the present invention, the outer shell component (B)
You may use the thing whose melting point of is higher than the melting point of a core component (A). In this case, the core component (A) is used as the fusing component. The core component (A) is surrounded by a plurality of outer shell components (B), but since there is a gap between adjacent outer shell components (B), the outer shell component (B) is still separated. If not, the core component (A) is softened or melted in this gap and fused with other composite long fibers. Also,
After the core component (A) and the outer shell component (B) are separated, the outer shell component (B) is fused to each other by softening or melting the core component (A). Core component (A) and outer shell component (B)
Any combination may be used as long as the melting point of the core component (A) is lower. As the polymer component that is not specifically adopted, the above-mentioned combination (combination when the melting point of the outer shell component (B) is lower)
The opposite combination may be adopted.

The weight ratio of the shell component (B) is preferably 30 to 70% by weight based on the total weight. When the weight ratio of the outer shell component (B) is less than 30% by weight, the weight ratio of the core component (A) becomes relatively large, and the fineness of the core component (A) tends to be large, resulting in a nonwoven fabric obtained. The texture tends to decrease. Generally, the fineness of the core component (A) is preferably less than 4 denier. When the weight ratio of the outer shell component (B) exceeds 70% by weight, the joint area between the core component (A) and the outer shell component (B) becomes large,
By the split splitting process, both components tend to be difficult to separate, and the fineness of the ultrafine fibers produced by separating the outer shell component (B) tends to increase. Generally, the fineness of the individual shell component (B) is preferably less than 1 denier, particularly preferably about 0.1 to 0.8 denier. It is difficult to adjust the fineness of the outer shell component (B) to less than 0.1 denier in terms of production of composite long fibers by melt spinning. When the fineness of the outer shell component (B) exceeds 1 denier, the stain removability tends to decrease. The fineness of the composite long fibers is a matter that can be set arbitrarily.

The composite long fibers are used to form a fibrous web by any method. As a method for producing a fibrous web, a composite long fiber is produced by a conventionally known melt-spinning method, a fiber web is produced by taking out the composite filaments, and then spreading and accumulating the fiber web by a so-called spunbond method. Is preferably created. The fibrous web may have any basis weight, but it is generally preferably about 10 to ²⁰⁰ g / m ² .
When the basis weight of the fibrous web is less than 10 g / m ² , the amount of the composite long fibers is small, and the strength of the resulting nonwoven fabric tends to decrease. On the other hand, when the basis weight exceeds 200 g / m ² , the thickness of the obtained nonwoven fabric becomes too thick, which may cause delamination.

Then, heat and pressure are partially applied to the fibrous web by a conventionally known method. As a method of partially applying heat and pressure, it is preferable to employ a so-called embossing method in which a fibrous web is passed between a heated uneven roll and a smooth or uneven roll. When this embossing method is adopted, a large number of convex portions of the heated concavo-convex roll are brought into contact with the fibrous web, and heat and pressure are applied to this portion, and heat and pressure are partially applied to the fibrous web as a whole. Of. The heating temperature of the heated concavo-convex roll may be a temperature at which the outer shell component in the composite long fiber softens or melts when the outer shell component has a low melting point, and when the core component has a low melting point. It does not matter if the temperature is such that the core component in the composite long fiber softens or melts. Also, the linear pressure (pressure) between the heated uneven roll and the smooth or uneven roll.
Also, when the outer shell component has a low melting point, the pressure may be such that the outer shell component softens or melts, and when the core component has a low melting point, the pressure may be such that the core component softens or melts. Absent.

When heat and pressure are applied to the fibrous web, the outer shell component or core component, which is a low melting point component in the composite long fibers constituting the fibrous web, is softened or melted, and the composite long fibers are separated from each other. Fused. And, since the heat and pressure are partially applied, a large number of fusion zones are provided. In the present invention, the fusion-bonded area formed by fusion-bonding the composite long fibers to each other is called the first fusion-bonded area. this is,
This is for distinguishing from the fusion-bonding area provided after splitting and splitting the composite continuous fiber, and the fusion-bonding area provided later is called the second fusion-bonding area in the present invention.

The individual area of the first fusion-bonding area is a matter which can be set arbitrarily, but in general, it is preferably about 0.1 to 3.0 mm ² . Any shape may be used as the shape of each first fusion-bonding area. For example, any shape such as a circle, a triangle, an ellipse, a quadrangle such as a square or a rhombus, and a slit shape may be adopted. You can Further, the density of the first fusion-bonding area is also a matter that can be arbitrarily set, but it is generally preferably ² to 100 pieces / cm ² , and particularly 4 to
Most preferably, it is 60 / cm ² . Further, the ratio of the first fusion bonding area to the entire surface of the fibrous web can be set arbitrarily, but it is generally preferably 2 to 50%, and particularly preferably 4 to 20%. Since the first fusion-bonding area plays a role of holding the ultrafine fibers generated by the split split fibers, the individual area is less than 0.1 mm ² or the density is less than 2 pieces / cm ² . If there is, or the ratio is less than 2%, there is a tendency that the role of holding the ultrafine fibers is reduced. In addition, since the composite long fibers in the area outside the first fusion-bonding area, that is, in the non-fusion-bonding area are separated into each component by the split split fibers to produce ultrafine fibers, each area is 3.0 mm ^2.
When the density exceeds 100, the density exceeds 100 / mm ² , or the ratio exceeds 50%, the ratio of the ultrafine fibers generated by the split split fibers tends to decrease, and the resulting non-woven fabric has good stain removal. It tends to be difficult to impart sex.

After the fiber web is provided with the first fusion-bonded area, a split splitting treatment is performed. Conventionally known means can be adopted as a specific means of the splitting and splitting treatment. For example,
When introducing the fibrous web between the pair of rolls, a buckling bending method can be adopted in which the introducing speed is made faster than the drawing speed to bend the fibrous web (that is, the composite long fibers).
It is also possible to employ a high pressure liquid flow treatment method in which a high pressure liquid flow is applied to the fibrous web and the composite filaments are bent by this liquid flow. In addition, any method may be adopted as long as it has a rubbing action or a bending action that splits and splits the composite long fibers. When the buckling bending method is adopted, it is preferable to use a Microcreper machine manufactured by Mike Rex or a cam fit machine manufactured by Uenoyama Kiko. When the high-pressure liquid stream treatment method is adopted, it is preferable to use a commonly used high-pressure liquid stream dyeing machine or a water needling machine for ejecting a high-pressure liquid film stream or a high-pressure liquid columnar stream. . When the high pressure liquid flow treatment method is adopted, the fibrous web gets wet, so that it is necessary to add a drying step. From this point as well, it is preferable to adopt the buckling bending method.

By performing the splitting and splitting treatment, the core component and the outer shell component in the composite long fiber are separated, and ultrafine fibers are formed by the outer shell component to obtain a fiber fleece. The splitting rate, which is the rate at which the core component and the outer shell component are separated by the split splitting treatment, is preferably 60% or more, and particularly preferably 70% or more. If the splitting ratio is less than 60%, the amount of ultrafine fibers produced becomes small, and the wiping property tends to deteriorate. When a low melting point one is adopted as the outer shell component and a high melting point one is adopted as the core component, the composite long fibers in the first fusion zone are fused by the softening or melting of the outer shell component. The core component is surrounded by the softened or melted outer shell component. Therefore, the core component and the outer shell component of the composite long fibers existing in the first fusion-bonding zone are difficult to separate, and the splitting ratio tends to be low. On the other hand, when the core component having a low melting point and the outer shell component having a high melting point are used, the composite long fibers in the first fusion zone are fused by the softening or melting of the core component. Therefore, the core component is in a state of flowing out of the outer shell component, and is less likely to be surrounded by the outer shell component. Therefore, the core component and the outer shell component of the composite long fiber existing in the first fusion-bonding region are relatively easy to separate, and the splitting ratio tends to increase. Therefore, when the latter composite long fibers are adopted, the production rate of the ultrafine fibers becomes higher, the feeling becomes softer, and a wiping cloth having an improved wiping property can be obtained.

Depending on the method of divided splitting treatment (for example,
When a high-pressure liquid columnar flow is used), the separated core component and outer shell component may be entangled three-dimensionally, but in the present invention, it is desirable to prevent this three-dimensional entanglement from occurring. preferable. The reason for this is that if three-dimensional entanglement occurs, the texture of the resulting nonwoven fabric may deteriorate. Therefore, it is preferable to adopt a buckling bending method in which three-dimensional entanglement is less likely to occur, or a treatment with a high-pressure liquid dyeing machine or a high-pressure liquid film flow, as the method of the divided splitting treatment. In the present invention, a composite long fiber which is a constituent fiber is integrated and formed into a sheet in a state where it is not yet separated, and is referred to as a fibrous web. The composite long fiber which is a constituent fiber has a core component and an outer shell component. What is collected in the state of being separated and is made into a sheet is called a fiber fleece. In the present invention,
Before the split fiber treatment, the composite long fibers in the fiber web are fused to each other by the softening or melting of the outer shell component or the softening or melting of the core component. The fibers will also be tethered by this first fusion zone. Therefore, even after the splitting and splitting treatment, the fine fibers can be prevented from being wound around the nip roll side even if they are conveyed while being pressed and held by the nip roll.

After the splitting and splitting treatment, the fibers are conveyed by a nip roll or the like, and then the heat and pressure are partially applied to the fiber fleece to provide the second fusing zone. As a method of partially applying heat and pressure, the same method as the method of providing the first fusion bonding zone can be adopted. When heat and pressure are applied to the fiber fleece, when the outer shell component has a low melting point, the ultrafine fibers composed of the outer shell component in the fiber fleece are softened or melted, and the core components are fused to each other, resulting in the second fusion. A landing area is provided. Further, when the core component has a low melting point, the core component in the fiber fleece is softened and melted, and the ultrafine fibers made of the outer shell component are fused to each other to provide the second fusion zone. Each area of the second fusion zone, the shape of the second fusion zone, the density of the second fusion zone, the ratio of the second fusion zone to the entire surface of the fiber fleece is a matter that can be set arbitrarily, respectively. It may be the same as in the case of the first fusion zone. This second fusion zone is for imparting morphological stability that can be used in the resulting nonwoven fabric, and therefore, than in the case of the first fusion zone which simply serves to hold the ultrafine fibers together. It is preferable that each area is large, its density is also high, and its ratio is also large.

From the above, it is preferable that the degree of fusion in the second fusion zone is stronger than the degree of fusion in the first fusion zone. That is, it is possible to realize stronger fusion by setting the second fusion zone by setting the heat and the pressure to be applied partially higher. For example, when the outer shell component has a low melting point, the heat applied when the first fusion-bonding zone is provided is 5 to 70 higher than the melting point of the outer shell component in the composite long fiber.
Fusion of the second fusion-bonding zone is performed such that heat applied at a temperature lower than the melting point of the outer shell component by 0 to 30 degrees Celsius is applied at the time of providing the second fusion-bonding zone. The degree of may be increased. When the core component has a low melting point,
The heat applied when providing the first fusion bonding area is applied at a temperature 5 to 70 ° C. lower than the melting point of the core component in the composite long fiber,
The heat applied when the second fusion-bonding zone is provided may be applied at a temperature 0 to 30 ° C. lower than the melting point of the core component to strengthen the degree of fusion in the second fusion-bonding zone. . That is, the amount of heat when providing the second fusion zone may be increased to strengthen the degree of fusion in the second fusion zone. Further, the pressure (linear pressure) applied when the first fusion-bonding area is provided is less than 80 kg / cm, and the pressure (linear pressure) applied when the second fusion-bonding area is provided is 10-150 kg / cm. The degree of fusion in the two fusion zones may be increased.

The manufacturing method according to an example of the present invention will be described below with reference to FIG. First, the melt-spun composite long fibers 1 are accumulated on a conveyor 2 to obtain a fiber web 3. The fibrous web 3 is passed between the heated concavo-convex roll 4 and the smooth roll 5 to provide a first fusion zone. After this, the fibrous web 3 is Microcreper II
The composite long fiber 1 is passed through the fiber 6, and is split and split. Then, the fiber fleece 9 is conveyed by being gripped by the two pairs of nip rolls 7 and 8 at an appropriate speed. Then, the fiber fleece 9 is heated by the uneven roll 1-
A second fusion-bonding area is provided by passing between the and the smooth roll 11. Then, the obtained nonwoven fabric 13 is wound around the winding roll 12.

The non-woven fabric obtained as described above has a large number of first fusion-bonding areas and a large number of second fusion-bonding areas. When the outer shell component having a low melting point is used, in the first fusion zone, the composite long fibers are fused by softening or melting of the outer shell component, and in the second fusion zone. The core components are fused to each other by softening or melting the outer shell component separated from the core component. Further, when the core component having a low melting point is used, in the first fusion zone, the composite long fibers are fused to each other by softening or melting of the core component, and in the second fusion zone, the core The components are fused by softening or fusing. When the degree of fusion of the second fusion zone is made stronger than the degree of fusion of the first fusion zone, the degree of softening or melting of the outer shell component or the degree of softening or fusion of the core component becomes high. As a result, the thickness of the second fusion-bonding area becomes smaller than the thickness of the first fusion-bonding area. Then, in the area outside the first fusion-bonding area and the second fusion-bonding area (non-fusion-bonding area), the ultrafine fibers composed of the outer shell component are generated due to the split splitting of the composite long fibers. Since such a non-woven fabric contains ultrafine fibers in the non-fused area, it has excellent stain removal performance,
It can be suitably used as a lens cloth for glasses or the like, or other cloth.

[0025]

【Example】

Example 1 As an outer shell component, a high-density polyethylene having a melting point of 130 ° C. and a melt index value (measured according to the method described in ASTM D1238 (E)) of 20 g / 10 minutes was prepared. On the other hand, as a core component, polyethylene terephthalate having a melting point of 258 ° C. and a relative viscosity of 1.38 at 20 ° C. when dissolved in an equal amount mixed solvent of tetrachlorofuran and phenol was prepared. Then, using both components, composite melt spinning was performed, and a composite continuous fiber having a cross-sectional shape as shown in FIG. 1 and a fineness of 2.70 denier was obtained. Then, the composite long fibers are accumulated to give a basis weight of 60 g /
An m ² fiber web was created. This fibrous web is
The fibrous web was introduced between a concavo-convex roll heated to 0 ° C. and a smooth roll heated to 80 ° C., a linear pressure of 15 kg / cm was applied to the fibrous web, and a large number of circular first fusion zones were provided. The individual area of this first fused area was 0.2 mm ² , its density was 7.5 pieces / cm ² , and the ratio of the first fused area to the entire surface of the fibrous web was 1.5%. It was

Next, the fibrous web provided with the first fusion-bonding area was applied to Microcreper II manufactured by Mikelex Co., Ltd.
The composite filaments were split and split by the buckling bending method at a processing speed of 10 m / min. As a result, in the non-fusing zone outside the first fusion zone, the core component and the outer shell component in the composite filament were separated, and a large number of ultrafine fibers were produced. The fineness of the ultrafine fibers thus produced was about 0.25 denier. The fiber fleece thus obtained,
As shown in FIG. 7, the sheet was conveyed through two pairs of nip rolls. During this conveyance, the ultrafine fibers sometimes adhered to the nip roll, but they did not wind around the nip roll side.

The fiber fleece conveyed as described above is
Introduced between the concavo-convex roll heated to 120 ° C and the smooth roll heated to 120 ° C, 20 kg /
A linear pressure of cm was applied and a number of circular second fused areas were provided. The individual area of the second fused area was 0.8 mm ² , the density thereof was 20 pieces / cm ² , and the ratio of the second fused area to the entire surface of the fiber fleece was 16%. In the non-woven fabric obtained as described above, the thickness of the first fusion-bonding area was 0.3 mm, and the thickness of the second fusion-bonding area was 0.
It was 22 mm. Here, the thickness of each fused region is measured under no load. In addition, the first fusing area and the second fusing area had an overlapping area in a part thereof, but the thickness in that area was substantially the same as the thickness of the second fusing area. .

This non-woven fabric was cut into a size of 10 cm × 20 cm and used as a cleaning cloth for spectacle lenses. This wiping cloth is unlikely to stretch or break during use,
It was excellent in morphological stability and was able to satisfactorily remove lens stains.

Example 2 A nonwoven fabric was produced in the same manner as in Example 1 except that the temperature of the concavo-convex roll and the smooth roll at the time of providing the second fusing zone was 130 ° C. and the linear pressure was 15 kg / cm. did. Also in this case, as in the case of Example 1, the fiber fleece was not wound around the nip roll side. In the obtained nonwoven fabric, the thickness of the first fusion bonded area was 0.3 mm and the thickness of the second fusion bonded area was 0.2 mm. The spectacle lens wiping cloth obtained by cutting this non-woven fabric into an appropriate size had good usability and stain removability.

Example 3 A nonwoven fabric was produced in the same manner as in Example 1 except that the temperature of the concavo-convex roll and the smooth roll at the time of providing the second fusing zone was 110 ° C. and the linear pressure was 50 kg / cm. . Also in this case, as in the case of Example 1, the fiber fleece was not wound around the nip roll side. Also,
The thickness of the first fused area in the obtained nonwoven fabric is 0.3.
mm, and the thickness of the second fused area was 0.22 mm. The spectacle lens wiping cloth obtained by cutting this non-woven fabric into an appropriate size had good usability and stain removability.

Example 4 Nylon 6 having a melting point of 225 ° C. and a relative viscosity of 2.57 measured at 25 ° C. with 96% concentrated sulfuric acid was prepared as an outer shell component. On the other hand, as the core component, the same polyethylene terephthalate as that used in Example 1 was prepared. Then, in the same manner as in Example 1, a composite long fiber having a fineness of 2.70 denier was obtained, and the composite long fibers were accumulated to form a fiber web. This fibrous web was introduced between a concavo-convex roll heated to 210 ° C. and a smooth roll heated to 210 ° C., a linear pressure of 15 kg / cm was applied to the fibrous web, and a large number of circular first fusion-bonding areas were provided. Was set up. The individual area of this first fused area was 0.2 mm ² , its density was 7.5 pieces / cm ² , and the ratio of the first fused area to the entire surface of the fibrous web was 1.5%. It was

Thereafter, in the same manner as in Example 1, the composite long fibers were subjected to splitting and splitting treatment to obtain a fiber fleece in which ultrafine fibers having a fineness of about 0.25 denier were produced, and further conveyed. . Then, this fiber fleece was introduced between an uneven roll heated to 220 ° C. and a smooth roll heated to 220 ° C., a linear pressure of 25 kg / cm was applied to the fiber fleece, and a large number of circular second melts were applied. A dressing area was set up. The individual area of the second fused area was 0.8 mm ² , the density thereof was 20 pieces / cm ² , and the ratio of the second fused area to the entire surface of the fiber fleece was 16%. In the non-woven fabric obtained as described above, the thickness of the first fusion-bonded area was 0.
28 mm and the thickness of the second fused area was 0.18 mm. In addition, the first fusing area and the second fusing area had an overlapping area in a part thereof, but the thickness in that area was substantially the same as the thickness of the second fusing area. .

This non-woven fabric was cut into a size of 10 cm × 20 cm and used as a cloth for eyeglass lenses. This wiping cloth is unlikely to stretch or break during use,
It was excellent in morphological stability and was able to satisfactorily remove lens stains.

Example 5 Example 4 is repeated except that the split fiber treatment is carried out using a loco-type jet dyeing machine instead of using the Microclaper II.
A nonwoven fabric was produced in the same manner as in. At this time, the condition for applying the liquid flow to the fiber web was a nozzle pressure of 3 kg / cm ^2, and thereafter, the fiber fleece was conveyed by a nip roll and passed through a dehydration and drying step. In the obtained nonwoven fabric, the thickness of the first fusion bonded area was 0.3 mm and the thickness of the second fusion bonded area was 0.18 mm. The spectacle lens wiping cloth obtained by cutting this non-woven fabric into an appropriate size had good usability and stain removability.

Comparative Example 1 A nonwoven fabric was produced in the same manner as in Example 1 except that the first fusion-bonding area was not provided. In this case, after performing the splitting and splitting treatment with the Microclaper II and before providing the second fusion-bonding area, the fiber fleece was easily wrapped around the nip roll, and it was difficult to continuously manufacture the nonwoven fabric. .

Comparative Example 2 A non-woven fabric was produced in the same manner as in Example 1 except that the second fusing zone was not provided. This non-woven fabric was the same as the fiber fleece having only the first fusion bonded area, and when cut and used as a cleaning cloth for eyeglass lenses, it was easily stretched and was inferior in usability. Regarding the stain removability, it had substantially the same performance as the nonwoven fabric obtained by the method according to Example 1.

Example 6 As an outer shell component, there was prepared polyethylene terephthalate having a melting point of 258 ° C. and a relative viscosity of 1.38 at 20 ° C. when dissolved in an equal amount mixed solvent of tetrachlorofuran and phenol. On the other hand, the core component has a melting point of 130.
Melt index value at ℃ (ASTM D1238 (E)
A high-density polyethylene having a measurement value of 20 g / 10 minutes according to the method described in 1) was prepared. Then, using both components, composite melt spinning was performed, and a composite continuous fiber having a cross-sectional shape as shown in FIG. 1 and a fineness of 2.70 denier was obtained. Then, the composite long fibers are accumulated to give a basis weight of 60 g /
An m ² fiber web was created. This fibrous web is
It was introduced between an uneven roll heated at 0 ° C. and a smooth roll heated at 120 ° C., a linear pressure of 50 kg / cm was applied to the fibrous web, and a large number of circular first fusion zones were provided. The individual area of this first fusion zone is 0.2 mm ² .
The density was 7.5 pieces / cm ² , and the ratio of the first fused area to the entire surface of the fibrous web was 1.5%.

Next, the fibrous web provided with the first fusion-bonding area was applied to Microcreper II manufactured by Mikelex Co., Ltd.
The composite filaments were split and split by the buckling bending method at a processing speed of 10 m / min. As a result, in the non-fusing zone outside the first fusion zone, the core component and the outer shell component in the composite filament were separated, and a large number of ultrafine fibers were produced. The fineness of the ultrafine fibers thus produced was about 0.25 denier. The fiber fleece thus obtained,
As shown in FIG. 7, the sheet was conveyed through two pairs of nip rolls. During this conveyance, the ultrafine fibers sometimes adhered to the nip roll, but they did not wind around the nip roll side.

The fiber fleece conveyed as described above is
Introduced between the concavo-convex roll heated to 125 ° C and the smooth roll heated to 125 ° C, 100 kg of fiber fleece
A linear pressure of / cm was applied and a number of circular second fused areas were provided. The individual area of this second fusion zone is 0.8 mm ²
The density was 20 pieces / cm ² , and the ratio of the second fusion bonded area to the entire surface of the fiber fleece was 16%.
In the nonwoven fabric obtained as described above, the thickness of the first fusion bonded area was 0.30 mm and the thickness of the second fusion bonded area was 0.22 mm. Here, the thickness of each fusion zone is
It is measured under no load. In addition, the first fusing area and the second fusing area had an overlapping area in a part thereof, but the thickness in that area was substantially the same as the thickness of the second fusing area. .

This nonwoven fabric was cut into a size of 10 cm × 20 cm and used as a cloth for eyeglass lenses. This wiping cloth is unlikely to stretch or break during use,
It was excellent in morphological stability and was able to satisfactorily remove lens stains. In addition, Example 1
As compared with the cleaning cloth for eyeglass lenses obtained by the method according to any one of 1 to 5, the texture was soft and the stain removability was excellent.

Example 7 As the shell component, the same polyethylene terephthalate as used in Example 1 was prepared. On the other hand, as the core component, nylon 6 having a melting point of 225 ° C. and a relative viscosity of 2.57 measured at 25 ° C. with 96% concentrated sulfuric acid was prepared. Then, in the same manner as in Example 1, the fineness is 2.70.
A denier composite filament was obtained, and the composite filament was accumulated to form a fibrous web. This fibrous web was introduced between a concavo-convex roll heated to 210 ° C. and a smooth roll heated to 210 ° C., a linear pressure of 15 kg / cm was applied to the fibrous web, and a large number of circular first fusion-bonding areas were provided. Was set up. The individual area of this first fused area was 0.2 mm ² , its density was 7.5 pieces / cm ² , and the ratio of the first fused area to the entire surface of the fibrous web was 1.5%. It was

Thereafter, in the same manner as in Example 1, the composite long fibers were subjected to splitting and splitting treatment to obtain a fiber fleece in which ultrafine fibers having a fineness of about 0.25 denier were produced and further conveyed. . Then, this fiber fleece was introduced between an uneven roll heated to 220 ° C. and a smooth roll heated to 220 ° C., a linear pressure of 25 kg / cm was applied to the fiber fleece, and a large number of circular second melts were applied. A dressing area was set up. The individual area of the second fused area was 0.8 mm ² , the density thereof was 20 pieces / cm ² , and the ratio of the second fused area to the entire surface of the fiber fleece was 16%. In the non-woven fabric obtained as described above, the thickness of the first fusion-bonded area was 0.
28 mm, and the thickness of the second fused area was 0.20 mm. In addition, the first fusing area and the second fusing area had an overlapping area in a part thereof, but the thickness in that area was substantially the same as the thickness of the second fusing area. .

This non-woven fabric was cut into a size of 10 cm × 20 cm and used as a cloth for spectacle lenses. This wiping cloth is unlikely to stretch or break during use,
It was excellent in morphological stability and was able to satisfactorily remove lens stains. In addition, Example 1
As compared with the cleaning cloth for eyeglass lenses obtained by the method according to any one of 1 to 5, the texture was soft and the stain removability was excellent.

Example 8 Example 7 is repeated except that a split fiber treatment is carried out using a loco-type jet dyeing machine instead of using the Microclaper II.
A nonwoven fabric was produced in the same manner as in. At this time, the condition for applying the liquid flow to the fiber web was a nozzle pressure of 3 kg / cm ^2, and thereafter, the fiber fleece was conveyed by a nip roll and passed through a dehydration and drying step. In the obtained nonwoven fabric, the thickness of the first fusion bonded area was 0.3 mm and the thickness of the second fusion bonded area was 0.18 mm. The spectacle lens wiping cloth obtained by cutting this non-woven fabric into an appropriate size had good usability and stain removability. It should be noted that, compared with the wipes for eyeglass lenses obtained by the methods according to Examples 1 to 5, the feeling was soft and the stain removability was excellent.

Comparative Example 3 A nonwoven fabric was produced in the same manner as in Example 6 except that the first fusion-bonding area was not provided. In this case, after performing the splitting and splitting treatment with the Microclaper II and before providing the second fusion-bonding area, the fiber fleece was easily wrapped around the nip roll, and it was difficult to continuously manufacture the nonwoven fabric. .

Comparative Example 4 A nonwoven fabric was produced in the same manner as in Example 6 except that the second fusion-bonding area was not provided. This non-woven fabric was the same as the fiber fleece having only the first fusion bonded area, and when cut and used as a cleaning cloth for eyeglass lenses, it was easily stretched and was inferior in usability. Regarding the stain removability, the non-woven fabric obtained by the method according to Example 6 had substantially the same performance.

As is apparent from the above Examples 1 to 8 and Comparative Examples 1 to 4, the method according to the example is such that the splitting treatment is performed after the first fusion zone is provided, and By providing the two fusion bonded areas, a nonwoven fabric containing ultrafine fibers can be continuously and reasonably manufactured, and a nonwoven fabric that can be suitably used as a wiping cloth can be obtained. On the other hand, when the first fusion-bonding area is not provided, a nonwoven fabric containing ultrafine fibers cannot be reasonably manufactured continuously, and when the second fusion-bonding area is not provided, the wiping is performed. It is understood that it is not possible to obtain a non-woven fabric that can be suitably used as a cloth. Moreover, when comparing the wiping cloths obtained by the methods according to Examples 1 to 4 with the wiping cloths obtained by the methods according to Examples 5 to 8, the latter wiping cloth is softer and has stain removability. It was also excellent in terms of.

[0048]

According to the present invention, the first fusion zone is provided in the fibrous web formed of the splittable composite filaments, whereby the composite filaments are fused and fixed to each other. Therefore, when the ultrafine fibers are generated by the subsequent splitting and splitting treatment, the ultrafine fibers are connected by the first fusion-bonding area which is the fusion-bonding fixing area. Accordingly, when the fiber fleece containing the generated ultrafine fibers is conveyed by the nip roll, it is possible to prevent the ultrafine fibers from adhering to the surface of the nip roll and winding the fiber fleece on the nip roll side. Then, a second fusing zone is further provided on the fiber fleece, and the core components are fused and fixed with the ultrafine fibers, or the ultrafine fibers are fused and fixed with the core component to obtain a nonwoven fabric. Therefore, this nonwoven fabric has excellent morphological stability. Further, in the non-fusing area outside the first fusing area and the second fusing area, ultrafine fibers are formed, and therefore, when used as a wiping cloth, the stain removability is excellent.

[0049]

As a result of the above, when the nonwoven fabric is manufactured by the method according to the present invention, the fiber fleece can be prevented from being wound around the nip roll when the fiber fleece is conveyed by the nip roll during the manufacturing, so that continuous production is possible. Therefore, the non-woven fabric can be reasonably manufactured. Further, since the nonwoven fabric according to the present invention is excellent in shape stability and stain removability, it has an effect that it can be suitably used as a wiping cloth for eyeglass lenses and the like. In the above description, the case where the non-woven fabric according to the present invention is mainly used as a wiping fabric has been described, but it goes without saying that it can be applied to other uses.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a composite long fiber used in the present invention.

FIG. 2 is a cross-sectional view showing an example of a composite long fiber used in the present invention.

FIG. 3 is a cross-sectional view showing an example of a composite long fiber used in the present invention.

FIG. 4 is a cross-sectional view showing an example of a composite long fiber used in the present invention.

FIG. 5 is a cross-sectional view of a composite continuous fiber for explaining a preferred example of the composite continuous fiber used in the present invention.

FIG. 6 is a cross-sectional view of a composite continuous fiber for explaining a preferred example of the composite continuous fiber used in the present invention.

FIG. 7 is a schematic view showing an entire manufacturing method according to an example of the present invention.

[Explanation of symbols]

 1 Composite long fiber 3 Fiber web 7 Nip roll 8 Nip roll 9 Fiber fleece 13 Non-woven fabric

Claims (9)

[Claims] 1. A non-woven fabric formed by using a composite long fiber composed of a core component and a plurality of outer shell components bonded to the outer peripheral portion of the core component and having a melting point lower than the melting point of the core component,
The non-woven fabric comprises a plurality of first fusing zones and a plurality of second fusing zones, wherein the first fusing zones are bonded to the core component between the composite filaments. The outer shell component is fused and formed by softening or melting, and in the second fusion zone, the core component and the outer shell component in the composite continuous fiber are separated from each other, and the core component is separated from each other. Is fused and formed by softening or melting of the outer shell component, and is formed with the core component in the composite long fiber in the region outside the first fusion zone and the second fusion zone. A non-woven fabric characterized in that the outer shell component is separated to form ultrafine fibers composed of the outer shell component. 2. A nonwoven fabric formed by using a composite long fiber comprising a core component and a plurality of outer shell components bonded to the outer peripheral portion of the core component and having a melting point higher than the melting point of the core component,
The non-woven fabric comprises a plurality of first fusion zones and a plurality of second fusion zones, wherein the first fusion zones are fused between the composite long fibers by softening or melting the core component. The second fusion-bonded area is separated from the core component and the outer shell component in the composite continuous fiber, and the outer shell component is separated from each other.
The core component is formed by being fused by softening or melting of the core component, and in the region outside the first fusion zone and the second fusion zone, the core component in the composite long fiber and the outer shell A non-woven fabric characterized in that ultrafine fibers composed of the outer shell component are produced by separating the components. 3. The nonwoven fabric according to claim 1, wherein the thickness of the second fusion-bonding area is smaller than the thickness of the first fusion-bonding area. 4. A non-woven cloth made of the non-woven fabric according to any one of claims 1 to 3. 5. A fibrous web is prepared by accumulating composite long fibers composed of a core component and a plurality of outer shell components bonded to the outer peripheral portion of the core component and having a melting point lower than the melting point of the core component. After softening or melting the outer shell component by partially applying heat and pressure to the fibrous web and providing a plurality of first fusing zones where the composite filaments are fused together. , Split fiber treatment is performed to separate the core component and the outer shell component of the composite long fiber in a region other than the first fusion-bonded region, and an ultrafine fiber composed of the outer shell component is generated to produce a fiber. By making a fleece and then partially applying heat and pressure to the fiber fleece, the ultrafine fibers are softened or melted to create a number of second fused zones where the core components are fused together. A method for manufacturing a non-woven fabric, which is characterized by being provided. 6. A fibrous web is prepared by accumulating composite long fibers composed of a core component and a plurality of outer shell components bonded to the outer peripheral portion of the core component and having a melting point higher than the melting point of the core component. , By softening or melting the core component by partially applying heat and pressure to the fibrous web to provide a large number of first fusion zones where the composite long fibers are fused to each other, A fiber fleece is produced by performing a split fiber treatment to separate the core component and the outer shell component of the composite long fiber in a region other than the first fusion-bonded region to generate ultrafine fibers composed of the outer shell component. And then partially applying heat and pressure to the fiber fleece to soften or melt the core component to provide multiple second fusing zones where the ultrafine fibers are fused together. A method for producing a non-woven fabric, comprising: 7. The method for producing a nonwoven fabric according to claim 5, wherein the heat for providing the second fusion-bonding area has a larger amount of heat than the heat for providing the first fusion-bonding area. 8. The method for producing a nonwoven fabric according to claim 5, wherein the pressure when the second fusion-bonding area is provided is higher than the pressure when the first fusion-bonding area is provided. 9. A method for manufacturing a non-woven cloth according to any one of claims 5 to 8, wherein the non-woven cloth obtained by the method according to claim 5 is cut into an arbitrary shape.