JPH0116945B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for producing a new highly entangled felt suitable for producing superior nonwoven fabrics, superior suedes, and artificial leathers with silver surfaces.

(Prior Art) It is well known that a fiber entangled felt is produced by needle punching a sheet-like fiber web.

Normally, when needle punching is performed, it is processed using a needle punch machine or what is called a fiber locker room, but in order to obtain a good needle felt, the size and shape of the barb,
The number and other factors are appropriately selected, and the "needle depth" that does not penetrate more than the thickness of the fiber web, based on the position of the needle barb near the needle tip, is the "needle depth" that does not penetrate more than the thickness of the fiber web. needle punched at 'depth'.
In other words, when using a perforated bed plate in a needle punch machine, set the position of the bed plate so that the barb position of the needle does not exceed the surface of the needle, or even if it exceeds it only a little. (The idea is the same for both upward and downward punches.) The same goes for needle punching from the back side. This is generally repeated from the front and back. Because the fibers were caught on the barbs and did not protrude beyond the opposite side, a felt with an extremely clean surface appearance was formed. However, typical fiber sheet materials include the random web method and the cross wrapper method combined with a card machine, but there are few fibers lined up in the longitudinal direction of the sheet, and the felt may stretch during needle punching. If it stretches during the process of making artificial leather, or if it is further processed into a suede-like shape by raising or buffing, it greatly depends on the properties and micromorphology of the polymeric elastic material used at the same time. It had the disadvantage that it could not necessarily be said to be particularly strong against ``. Momoke refers to the change in the collar, elbows, etc. from a suede-like appearance to a blanket-like appearance during practical use.

In particular, when forming a web using a combination of a card and a cross wrapper, the fiber thin layer web vertically arranged by the card can theoretically be formed using a cross wrapper.
In practice, although the fibers were held at a slight angle and crossed, they were almost completely horizontally arranged, and had extremely few vertically arranged fibers. For this reason, the above-mentioned drawbacks were even more severe.

(Problems to be Solved by the Invention) The first object of the present invention is to provide a needle punching method that provides a new reinforced felt structure with a large number of longitudinally aligned fiber components contributing to reinforcement. do. Furthermore, the purpose is to achieve faster entanglement than before, and to reduce the elongation of the sheet during needle punching and processing into artificial leather. Another purpose is when made into suede-like artificial leather,
The object of the present invention is to provide a felt that provides a durable base material with less "fluffing". Another object of the present invention is to provide a method for providing base materials such as strong felt and strong grained artificial leather. Also, during needle punching, no matter how uniform the web is fed, the weight (weight per unit area) of the edges gradually becomes larger than that of the center, but if this can be reduced even a little, then The purpose is also to provide a method for

(Means for solving problems) The gist of the present invention is as follows.

When manufacturing a fiber-entangled felt by needle-punching a sheet-like fiber web, [first stage] the needle-punching is performed so as to sufficiently penetrate the thickness of the fiber web, and the needling surface (A
(referred to as a surface), the fibers are made to protrude on the opposite side (referred to as a B side), [second step] the protruding fibers are mainly turned in the longitudinal direction of the sheet and to the opposite side (referred to as a B side),
[Third step] From the opposite side (Side B), a needle punch is applied to sufficiently penetrate the thickness of the fiber web to make the fibers protrude to the opposite side (Side A) of the needling side (Side B). The protruding fibers are turned to the opposite side (side A), and the operations of steps 1 to 3 are repeated at least once. Then, [fourth step] the barb depth is deep enough to penetrate to the opposite side. 1. A method for producing a highly entangled felt, which comprises applying needle punching or jet punching with a fluid selected from a back pressure of 10 to 300 Kg/cm ² of a fluid discharge nozzle.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 shows the state of needle punching a cross section of a web together with a needle (also referred to as a felting needle), particularly a cross section along the longitudinal direction of the web.

In the figure, 1 is a web, 2 is a needle, and 3 is a barb attached to the needle (an enlarged example is shown in Figure 6), which fulfills the role of hooking and moving fibers. It can be said that there is. 4 is the fiber being moved by this barb. 5 is a fiber moved by needle punching.

"Barb depth" refers to the bottom surface of the web or felt, that is, from the surface (B side) opposite to the surface into which the needle is inserted (Side A), that is, from the surface of the bed plate.
It is defined as the distance in the needle direction (direction of movement of the needle beam) to the barb when the barb is penetrated the deepest. It must be noted that in strict terms, there is no direct relationship to the position of the needle tip, that is, the needle depth. For example, if there is a barb 4 mm from the needle tip and the barb depth is 5 mm, then the needle depth is 9 mm. This shows how long the fibers protrude from the opposite side (side B).

In the present invention, the barb depth in the first stage is 8
mm or more is preferable. This is because if the depth is shallower than that, the entanglement referred to in the present invention is sufficiently difficult to occur.

The location of the barb on the needle is important. It is particularly preferred that one barb is provided within at least 4 mm from the needle tip. This is because if the barb is located too far away, the "needle depth" must be too large in order to bring out the effects of the present invention, and in this case the needle marks will generally become noticeable and become needle streaks, resulting in a good quality of felt. This is because they tend to hinder the formation of. In this sense, the number of barbs per needle is particularly preferably one. More preferably, the barb is so small that it does not substantially catch three or more fibers during one needle punch. There are many barbs,
If the barbs are too large, the fibers may move too much all at once, resulting in poor uniformity.

FIG. 2 is a diagram showing the state of "fibers sufficiently protruded" from the front surface (side A) to the back surface (side B) by needle punching, that is, needling. That is, 1 is a web, and 5 (5 needles, 5 two needles) is a fiber moved by a needle punch.

Next, the fibers 5 protruded in the direction of this B plane
(5 darts, 5 two darts) on the B side. To do this, simply stroke the B side with something. Particularly preferred are those with a rough surface, such as a brush, cloth, or rubber surface. This may be any shape such as a plate, roll, or rod. In punch machines that use bed plates that are relatively uneven, when the punched web (called felt) is taken up or rolled up, the fibers in 5 are rubbed and form 6 in Figure 3. ) to be defeated. FIG. 3 shows a state in which the protruded fibers are turned over on the opposite side, that is, on the B side. It should be noted that this is done mainly in the longitudinal direction. There is no need to explain how the fibers protruding in the longitudinal direction are rubbed or toppled, and can be easily understood. The following description will focus particularly on such fibers. FIG. 4 shows how the felt is needle-punched by turning it over (or by needle-punching it from the opposite direction without turning it over. 1 is the web. The same applies hereafter). That is, FIG. 4 shows the state of needle punching from the opposite direction based on the present invention. FIG. 5 further shows the situation when needle punching is performed from above. The needle punch at this stage preferably has a barb depth of 5 mm or more. This is because the purpose is not only to deeply penetrate the fibers moved by the punch in the opposite direction, but also to move other fibers in the same manner as above. This allows the entanglement from the opposite side to proceed in a well-balanced manner, making it possible to form a good felt. The fallen fibers 6 are pushed into the felt as if they were sewn with sewing thread, mainly in the longitudinal direction, like 7 (7 needles). It will be clearly understood that this creates a kind of stitch effect. When more fibers are pushed out by this needle punch, the condition shown in FIG. 2 is formed again, and similarly, the conditions shown in FIGS. 3 and 4 occur successively. Focusing on this specific fiber, it can be seen that the fiber seam is formed by the fibers within the web, and a strong stitch-like entanglement in the longitudinal direction is formed. It goes without saying that this has a much higher probability of forming every fiber in the web than with conventional methods, and that this occurs all over the sheet. Once entangled, it is commonly called felt.

However, if you leave it as it is, you will end up with an unpalatable felt that is fluffed all over the surface, so it is important to ``sequently perform needle punching so that the fibers do not remain protruding from the surface of the felt.'' Therefore, it is necessary to add a needle punch with a barb depth of 3 mm or less, preferably 1 mm or less, to level the felt surface. It must be noted that the gist of this is very different from the deep needle punch at the preliminary stage. This allows the protruding fibers to be entangled and housed in the felt.

There is a way to achieve this. It is a fluid jet punch, typified by a water jet punch. Strong water jet punches are used to cut fibers, boards, rocks, etc., but the back pressure of the mouthpiece for the jet must be set at 10 to 300 kg/cm ²
By making an appropriate selection within this range, the fibers can be entangled mainly on the felt surface. This fluid treatment is particularly suitable for the fourth stage process.
Fluid processing has the disadvantage of requiring a drying process since the felt gets wet, which requires extra cost and consumes energy.
This can be achieved by a combination of dynamics and interruptions.

As a result, the long fibers protruding from the surface of the felt are pushed into the felt.
If it is too strong, the fibers will stick out from the other side or be cut. Also, if it is too weak, entanglement will not proceed. However, as long as the pressure is within the above-mentioned range, an appropriate value can be easily found, depending on the nozzle diameter, length, and other factors.

FIG. 6 shows an example of a needle for needle punching (felting needle). Barb is 1-9
These are commonly used and can be selected and used as appropriate.
In the present invention, 1 is particularly preferred. Needle thickness ranges from straight to graduated needle thickness, and 1.
There are also products whose cross-sectional area is changed in stages, two stages, and three stages.
Well used. An appropriately long needle is used.

On the other hand, the results of double-sided punching are shown in FIGS. 7 and 8 using the same method of expression as in FIGS. 1 to 5 to show what the conventional good needle punching method is. In other words, it is common sense for a good needle punch to only perform needle punching in such a way that the needle barb does not protrude to the opposite side of the webbing or felt (because if you always hit deeply, you will only get felt with a fluffy surface). ) It is applied to both the front and back sides of the web or felt. FIG. 7 shows the entangled state of fibers when the web is subjected to a suitable (not too deep) needle punch from the surface according to a conventional method. When the fabric is turned over and further needle punched, the result is that the fibers simply stand up within the felt and no stitching effect is observed at all, as shown in Figure 8. (Even if you don't turn it over and push it up from below, it's relative and the same is true.) By repeating this, it will become even better and a neatly intertwined felt will be formed. Unlike the present invention, a felt with an entangled structure is formed. The same is true when using a needle with multiple needle punches. If the barb is located far away from the needle tip, which results in a shallow strike, the effect of ejecting the fibers will be shallow, and the fibers will simply mix into other fibers. The basic idea remains unchanged.

In the present invention, the length of the fibers protruding from the reverse side of the felt or web is preferably 5 mm or more, particularly preferably 8 mm or more and 50 mm. The fibers are turned upside down. To make this invention, here referred to as the second step, more effective, aids such as brushing, scratching with a wire brush or cloth, sandpaper or honing may be used. This latter effect of pulling out the fibers, that is, the action of protruding the fibers for a slightly longer period of time and then picking them up and pulling them out further, is particularly noticeable (when a strong action as described above is applied). It should be particularly noted that excellent effects are exhibited even when the barb depth in the first and third stage needle punches is between 4 and 8 mm. This is because the barb depth is 8mm due to this drawer.
This is because it brings about the same effect as the needle punch described above. In particular, when the fibers are microfiber-generating fibers such as splittable conjugate fibers, peelable conjugate fibers, polymer mutual array fibers, and specific polymer blend fibers, the fibers may be split during this process. Microfibers may occur partially or wholly, but this is often preferred as it improves the strength and durability of the felt.
This is because the entanglement of thick fibers and the entanglement of ultra-fine fibers coexist. Furthermore, when performing ultrafine fiber generation treatment in a later step, the entanglement of bundles of ultrafine fibers and the entanglement of ultrafine fibers coexist, giving an even better felt.

The web of the present invention may be a random web or a crosslap web. The fibers may be long fibers such as spunbond or directly spun fabrics, or short fibers.
Particularly preferred are those with crimp. Particularly preferred is a web of short fibers. In order to perform good needle punching, it is particularly preferable and important that the fibers be crimped. 30~ for short fibers
150mm is preferable. Crosslap web refers to a web forming machine that is normally connected from a card machine to a crosslapper. According to this, since the cross angle during fiber cross wrapping is generally extremely small, the fibers are arranged almost at right angles to the longitudinal direction (lengthwise direction of the sheet). This can be easily seen by folding and stacking a tape with long vertical stripes. This is because the fibers coming out of the card machine are substantially aligned in the longitudinal direction.

The object to be needle punched is not limited to just a single piece of felt. It is also extremely effective when the felts made as described above are used in layers. This is called veneer composite felt or composite veneer felt. This is particularly effective when later slicing the felt into two pieces to double the productivity.
The reason why conventional punch felt becomes weak is because the surface is buffed to make it fluffy.
This is because the type structure is cut off, leaving many pure type I fibers.

It is believed that the present invention has been sufficiently understood through the above explanation, and further examples according to the present invention will be described. However, the effectiveness of the present invention is not limited or construed as limited by this, but rather indicates the extent of application development.

(Example) Polymer mutual array fiber (number of islands) is a typical type of ultrafine fiber-generating fiber consisting of polyethylene terephthalate with an island component of 60%, polystyrene with a sea component of 40%, and polyethylene glycol (5 parts).
16), using fibers with 12 crimp threads/2.54 cm and a fiber length of 51 mm, this was applied to a card and then passed through a cross wrapper to create a cross wrap web. This was needle punched with one barb, and while the back surface was rubbed against the bed plate and the surface of a rubber roll having fine irregularities, it was rolled up and then needle punched from the back surface. The depth of penetration into the back surface of the barb during this needle punching was 15 mm. Next, needle punch was performed from the opposite side in the same manner. This process was repeated until the number of needle punches on both sides reached about 1500 needle punches/cm ² , and then a total of about 600 needle punches/cm ² were applied on both sides with the penetration depth to the back side of the barb being 0 mm. 530 with an apparent density of 0.21 g/ ^cm3 .
A felt of g/m ² was obtained. The webbing progresses extremely quickly, and compared to the conventional general method of repeatedly turning the front and back sides of a needle punch with a barb depth of 0 mm.
Although 3,000 pieces/cm ² were required, the density was increased very quickly (high productivity). Furthermore, when comparing the elongation during needle punching using the same needle punch machine, we were able to reduce elongation deformation by approximately 10%. To this material, a 12% aqueous solution of polyvinyl alcohol was applied, dried, thoroughly washed with trichlorethylene, then impregnated with a 12% solution of polyurethane in dimethylformamide, coagulated in water, and then washed with hot water. It was sliced into two pieces and buffed on both sides until a suede appearance was achieved without creating too deep a bubble. After that, it was dyed in a beige color with a disperse dye using a pressurized circular dyeing machine and dried. The abrasion resistance of this material (comparative evaluation using the Schieffer abrasion measurement method in which the brush is rubbed while rotating) was surprisingly about 30% higher than that obtained using the conventional needle punch method.

Even if this was not processed into suede, when the strength was compared at the felt stage, the felt produced by the method of the present invention had higher strength.

(Effect of the invention) Felt is provided as a base material with high wear resistance. In particular, when microfiber-generating fibers are used as suede-like materials after being made into microfibers and then impregnated with polyurethane and buffed, they exhibit particularly good abrasion resistance (fleshing resistance).

Increase needle punch efficiency. It quickly transforms into high-density felt and has high productivity. For that reason, the surface of the felt is beautiful.

There is little elongation during needle punching. That is, there is little deformation of the felt. Although the width changes quickly, it does not hinder the effectiveness of the present invention, but rather tends to significantly increase the unevenness of the felt weight in the width direction. This reduces the amount of buffing needed to obtain a similar suede surface, and allows a thinner felt design to be selected for the same product thickness, which is advantageous in terms of cost.

[Brief explanation of drawings]

FIG. 1 is a diagram (model diagram, the same applies hereinafter) to help understand the present invention, and shows a fiber web, needles (particularly barbs) in a needle punch, and moving fibers in the first step method according to the present invention. FIG. FIG. 2 is a diagram to help understand the present invention, and is a diagram showing the state of the fibers when deep needle punching is performed in the first stage of the present invention so that the fibers largely protrude from the back side. It is. FIG. 3 is a diagram to help understand the present invention, and shows the state after the fibers that protruded greatly on the back surface in the first step are collapsed on the back surface in the second step method according to the present invention. It is. FIG. 4 is a diagram showing a similar state when the felt of FIG. 3 is turned inside out. FIG. 5 is a diagram showing the movement of the target fibers when the felt of FIG. 4 is further subjected to needle punching. FIG. 6 shows a typical example of a felting needle. FIG. 7 is a model diagram illustrating the state of fibers after movement in needle punching according to the conventional method. FIG. 8 is a model view showing the state after fiber movement (no self-stacking effect at all) when needle punching is further applied by the conventional method from the opposite direction of FIG.

Claims (1)

[Scope of Claims] 1. When manufacturing a fiber entangled felt by needle punching a sheet-like fiber web, [first step] needle punching is performed so as to sufficiently penetrate the thickness of the fiber web. Ring surface (A
(referred to as a surface), the fibers are made to protrude on the opposite side (referred to as a B side), [second step] the protruding fibers are mainly turned in the longitudinal direction of the sheet and to the opposite side (referred to as a B side),
[Third step] From the opposite side (Side B), a needle punch is applied to sufficiently penetrate the thickness of the fiber web to make the fibers protrude to the opposite side (Side A) of the needling side (Side B). The protruding fibers are turned to the opposite side (side A), and the operations of steps 1 to 3 are repeated at least once. Then, [fourth step] the barb depth is deep enough to penetrate to the opposite side. 1. A method for producing a highly entangled felt, which comprises applying needle punching or jet punching with a fluid selected from a back pressure of 10 to 300 Kg/cm ² of a fluid discharge nozzle. 2. The highly entangled felt according to claim 1, wherein the sheet-like fiber web is a fiber web passed through a cross wrapper, in which the fibers are arranged in a direction substantially perpendicular to the longitudinal direction of the sheet. Production method. 3. The first claim characterized in that the fibers forming the sheet-like fiber web include ultrafine fiber-generating fibers that generate ultrafine fibers through a treatment that causes splitting or peeling or a treatment that removes one component. A method for producing a highly entangled felt as described in Section 1. 4. The method for producing a highly entangled felt according to claim 1, wherein the needle used for needle punching in the first and third steps has at least one barb within 4 mm from the needle tip. .