JPH0819611B2 - High-fitting non-woven fabric and its manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a non-woven fabric having an excellent fit property and a method for producing the same. Particularly, the non-woven fabric has an excellent fit property to the body, and its application is, for example, external use. The present invention relates to a non-woven fabric which can be suitably used mainly as a sanitary material, such as a medicine base cloth, a hand wipe impregnated with a medicine, a wiping cloth, clothes for doctors and sick people, gowns, and macula covers.

Conventional technology and its problems Conventional needle-punched non-woven fabrics have good strength, but generally tend to be bulky, and their fit to the body is not good. A non-woven fabric by hydroentanglement has been developed as a fiber entanglement means to replace the needle punch, and this technique involves injecting a high-pressure water column from an orifice to obtain inter-fiber entanglement of the web, and a non-woven fabric with a fairly good fit. It is a manufacturing method that can obtain

However, even in this hydroentangled non-woven fabric, when the degree of entanglement is increased, the strength is improved, but the elongation is limited, and as a result, the fit property is insufficient. Therefore, there is a problem that the fitting property becomes good but the strength becomes weak.

The present invention is intended to solve the problems of the above-mentioned hydroentangled nonwoven fabrics, and to provide a nonwoven fabric which is further improved in fit and has good strength.

(B) Structure and Action of the Invention The structure of the present invention is a non-woven fabric that contains side-by-side type crimpable fibers and is hydroentangled and has a basis weight of 90
The strength is g / m ² or less and the average length and width is 3 kg / 5 cm width or more, and the elongation recovery rate is 10% when the length and width average is 30% or more and 50% when the length and width average is 30%. A high-fitting non-woven fabric characterized by the following, and as a method for producing the same, a web containing at least 30% or more of side-by-side crimpable fibers is hydroentangled, and then heat-treated to obtain the latent crimpability. A method for producing a high-fitting non-woven fabric, which is characterized by expressing crimps of fibers.

Means for solving the problem By including crimped fibers in the constituent fibers of the nonwoven fabric by hydroentanglement, we succeeded in improving the fit property, and the basis weight, strength, and elongation recovery rate of the nonwoven fabric. If it is limited to a predetermined range, it becomes an extremely excellent non-woven fabric for sanitary materials, and as its manufacturing method, the latent crimpable fiber is contained in the web in a ratio of a predetermined range or more, and after hydroentangling this, It has been found that a highly suitable nonwoven fabric with high fit can be obtained by expressing crimps.

 The present invention will be described according to its manufacturing method.

First, fibers having latent crimpability are blended with a web as a raw material of a non-woven fabric at a ratio of at least 30% or more. If this mixing amount is less than 30%, the object of the present invention cannot be achieved and the fit property cannot be improved.

The amount of this mixture is preferably 50% or more, and may be composed of 100% latently crimpable fibers. In this case, the best result is obtained.

So-called side-by-side type composite fibers can be used as the latently crimpable fibers, and the crimps are expressed by the difference in shrinkage rate by the action of dry heat or wet heat.

Such a web is hydroentangled to form a nonwoven fabric, which is for injecting high-pressure columnar water streams from a large number of orifices to obtain interfiber entanglement, and the diameter of the orifices is 0.1 to 0.2 mm, The water pressure is preferably in the range of 10 to 60 kg / cm ² .

According to the experiments conducted by the present inventor, a relatively low degree of hydroentanglement produces a good result.

The hydroentangled nonwoven fabric thus obtained is dried and heat-treated by dry heat or wet heat with hot water or the like. The higher the processing temperature, the better, but it is needless to say that it needs to be below the melting point of the constituent fibers.

By this heat treatment, the side-by-side type crimpable fiber develops the crimp and becomes the nonwoven fabric of the present invention.

Since the non-woven fabric of the present invention has the greatest purpose of improving its fit, it is desirable that the thickness is inevitably small, usually 1 m or less, and if it is water entanglement, it is likely to be less than this thickness. , The basis weight is 90 g / m ²
Limiting to the following is a necessary condition for the fit that comes from the thickness.

The preferable range of the basis weight is 50 to 75 g / m ² , and a too small basis weight does not satisfy the strength condition.

The strength requirement of this non-woven fabric is 3 kg / vertical on average.
It is required that the width is 5 cm or more, and if the strength is lower than this, the nonwoven fabric cannot be used for the various applications mentioned above.

The most necessary condition for satisfying the fitting property of the nonwoven fabric of the present invention is that the elongation recovery rate is set within a predetermined range.

In other words, the nonwoven fabric of the present invention needs to have an elongation recovery rate of 30% or more in the vertical and horizontal directions at the time of 10% elongation, which is close to the original dimension when the tensile force is lost when slightly elongated. The condition is that it is easy to recover, while
When stretched 50%, it is necessary that the average length and width be 30% or less, which means that when stretched to a large extent, there is little recovery from that stretch even if the tensile force is removed.

In other words, it indicates that stretchability is necessary, but if the stretchability is too strong, the fit property will deteriorate.

This growth recovery rate is 30% on average in the vertical and horizontal directions at 10% growth
If it is less than the range, the elasticity is low and the fit to the body is poor. On the other hand, 30% vertical and horizontal average at 50% growth
In the case of a high elongation recovery rate of more than%, it is not preferable because there is too much stretchability and the dimensional stability during processing and the sewability deteriorate, and the problem of fluffiness during use occurs.

Since the nonwoven fabric of the present invention contains a large amount of crimpable fibers in its constituent fibers and is hydroentangled, it is easy to satisfy the above-mentioned various limiting conditions, and particularly the latent crimpable fibers. In the case of manufacturing by using, it is easy to entangle because it is not crimped at the time of hydroentangling, and it is possible to obtain a very favorable result in terms of strength because crimping is performed after entanglement is completed. It will be.

Needless to say, the non-woven fabric of the present invention can be obtained by using crimped fibers originally having crimps instead of latent crimped fibers as long as the above-mentioned conditions are satisfied.

Needless to say, various physical properties may be imparted to the nonwoven fabric of the present invention by post-processing, and for example, embossing for improving strength and abrasion resistance and other welding processing may be applied.

Example 1 A 100 g side-by-side type polyester composite fiber having a thickness of 2.5 d and a cut length of 51 mm was used as a latent crimpable fiber to form a web of 25 g / m ^{2 so} as to be oriented in one direction by a card method, After laminating a crosslay web made of 100% of the same composite fiber having the same basis weight as above,
Water entanglement by high pressure columnar water flow under the following conditions: 50.1 g /
An entangled sheet of m ² was obtained.

The high-pressure columnar water flow conditions are as follows: a nozzle with an orifice diameter of 0.15 mm and a number of orifices of 1000 / m at a speed of 5 m / min per step, first with a pressure of 12 kg / cm ² on the crosslay web side, and then reversing. 28 Kg / cm ² from one side of the web
It was performed so as to be jetted at a pressure of.

This sheet was dried with a dryer at 110 ° C., and then placed in a hot air oven at 190 ° C. for 1 minute to develop crimps, and a non-woven fabric of 76.3 g / m ² was obtained.

Various physical properties of this nonwoven fabric were measured before and after heat treatment. The results are shown in Table 1.

By developing crimping properties according to this table, strength and elongation are greatly improved, pilling is reduced and the feel is good, and the elongation recovery rate is high at low elongation and low at strong elongation, making it an ideal fit. It is understood that the dimensional stability is satisfied at the same time as the property.

In addition, the elongation recovery rate is measured by drawing a strong elongation curve as shown in FIG. 1 and measuring the areas of A and B. It is calculated and obtained in.

(The same applies to the following examples and comparative examples) Example 2 A web having the same conjugate fiber as that of Example 1 and the same overlap as that of Example 1 is hydroentangled under a condition that a higher entanglement is obtained as compared with Example 1. It was

The conditions are the same nozzle and processing speed as in Example 1, first, a high pressure water column of 10 Kg / cm ² on the crosslay web side, then a reversal of a high pressure water column of 50 Kg / cm ² , and a further reversal of a high pressure of 60 Kg / cm ² . The water column was reversed again, and a high-pressure water column of 20 Kg / cm ² was jetted, respectively.

Then, it was dried and heat-treated under the same conditions as in Example 1 to obtain the nonwoven fabric of the present invention.

Various physical properties of this nonwoven fabric were measured before and after heat treatment. Table 2 shows the results.

When the degree of hydroentanglement is higher than in this table, there is no problem in strength even if crimping is not expressed, but the stretchability when stretched a little is poor, and 10% by heat treatment of this
The elongation recovery rate during elongation is 30% or more, which falls within the range of the elongation recovery rate of the nonwoven fabric of the present invention.

However, since the value is close to the limit of this range, it is better not to perform stronger hydroentanglement to obtain a preferable result.

Example 3 The same conjugate fiber as in Example 1 was used 100%, a web was formed by the card method so as to be oriented in one direction, and the same nozzle and processing speed as in Example 1 were used to hydroentangle under the following conditions. It was

First, a high pressure water column of 24 kg / cm ² from the front side, then 24 from the back side.
A high-pressure water column of Kg / cm ² was jetted for each test.

Then, it was dried under the same conditions as in Example 1 and heat-treated to obtain the nonwoven fabric of the present invention.

When the physical properties of this product were measured, the results shown in Table 3 were obtained.

From this table, it is recognized that even with a unidirectional web, a non-woven fabric with excellent fit can be obtained by using crimpable fibers.

Comparative Example 1 10 mm latently crimpable polyester fiber 2.5 mm thick and 51 mm long
After the web consisting of 0% was needling at a needle density of 100 pieces / cm ² , the web was placed in a hot air oven at 190 ° C. for 1 minute to develop crimp, and a non-woven fabric having a basis weight of 93.5 g / m ² was obtained. Next, a belt press machine set at 150 ° C was used to reduce the thickness and improve the fit.

Various physical properties of the nonwoven fabric of Comparative Example 1 were measured before and after pressing.

 The results are shown in Table 4.

From this table, the non-woven fabric by needle punching has a large basis weight and the strength does not reach that of the non-woven fabric of the present invention even if the thickness is about 1 mm, and the elongation recovery rate is high even at 50% elongation and the elasticity is too strong, causing a problem in dimensional stability. It is determined that the

Example 4 A web composed of 60% of the same composite fiber as in Example 1 and 40% of a normal crimped 3d, 64 mm polyester fiber was hydroentangled under the same conditions as in Example 1 and heat treated in the same manner. The crimp was developed.

 The physical properties before and after this heat treatment are shown in Table 5.

Thus, even if the latent crimpable fiber and the non-crimpable fiber are blended, when the former is relatively large, the heat-crimping effect exhibited by heat treatment exhibits excellent high fit.

Example 5 The blending ratio in Example 4 was 40% for the composite fiber and 60% for the other fibers, and hydroentangling was performed under the following conditions with the same nozzle and processing speed as in Example 1.

First, 12 Kg / cm ² high-pressure water column from the front side,
A high-pressure water column of Kg / cm ^{2 and} a high-pressure water column of 40 Kg / cm ² were inverted and jetted.

Then, drying and heat treatment were performed under the same conditions as in Example 1.

 Various physical properties before and after the heat treatment are shown in Table 6.

In this case, the degree of hydroentangling is increased in order to increase the breaking strength to 3 kg or more. Therefore, the growth recovery rate at 10% growth is low at 38.7% on average.

Comparative Example 2 A nonwoven fabric was prepared in the same manner as in Example 4, except that the compounding ratio of Example 4 was 20% of the composite fiber and the other fiber was 80%.

Table 7 shows the physical properties of this product before and after heat treatment.

In this case, the strength is insufficient even after the heat treatment, and the elongation recovery rate at 10% elongation is too small, resulting in poor fit.

(C) Effect of the Invention The present invention is as described above, and is a non-woven fabric having a high fitting property and a method for producing the same, which is mainly composed of crimpable fibers and which is produced by hydroentanglement. In particular, it has excellent fit to the body, and also has good strength, and has excellent handling and suitability for use as various sanitary materials.
It has various excellent uses such as a wiping cloth and clothing for doctors, sick people, the elderly, etc., and its utility is extremely high.

[Brief description of drawings]

FIG. 1 is a graph of a strong elongation curve for explaining the elongation recovery rate in the present invention.

Claims (2)

[Claims] 1. A non-woven fabric containing side-by-side type crimpable fibers and hydroentangled, having a basis weight of 90 g / m ² or less and a strength of 3 kg / 5 cm width or more on a vertical / horizontal average.
And when the growth recovery rate is 10%, the vertical and horizontal average is 30
Non-woven fabric with a high fit, characterized by an average length of 30% or less when stretched by 50% or more at 50% or more. 2. A high-fitting method characterized in that a web containing at least 30% or more of side-by-side latent crimpable fibers is hydroentangled and then heat-treated to develop crimp of the latent crimpable fibers. For producing a flexible nonwoven fabric.