JPH0147590B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a method for manufacturing needle punch loop pile felt using fibers such as nylon, polyester, acrylic, etc., which are used as surface materials for electric carpets and the like.

(Background Art) Conventionally, as shown in Figure 1, this type of needle-punch felt has been produced using short fibers such as nylon, polyester, acrylic, etc. with a thickness of about 3 to 30 denier (about 1 to 3 inches in length). ) is made into a web-like thin cloth using a card machine, several sheets of the thin cloth are stacked and needle punched to make needle felt, and then the fibers are made to protrude from the felt surface using needle punching. We mainly make loop pile felt 4' with loop-like naps, and use SBR (styrene-butadiene rubber) or
The base fabric of the needle punch loop pile felt 4' is impregnated with a latex such as NBR (nitrile butadiene rubber) to approximately the thickness of the base fabric, and then heated and dried to form the backing resin layer 6 at the base of the pile, that is, at the base of the pile. By forming it on almost the entire surface of the felt base fabric, the fibers are kept entangled and the loop pile is prevented from coming off.

However, in the conventional method, since the bucking resin layer 6 is formed at the base of the loop pile, a lump of resin may occur, making it uncomfortable to sit on, or the resin layer 6 may fall out from the gap between the loop piles. This caused problems in practical use as pipe felt (carpet).

In addition, in order to eliminate this drawback, if the amount of latex used is reduced or the depth of latex impregnation is made thinner, the force that fixes the fibers in the loop pile part to the base fabric part will decrease, making hair pulling phenomenon more likely to occur.
There was a problem that the strength and dimensional stability of the felt were also reduced.

In addition, needle punch loop pile felt 4' is used as a surface material for electric carpets.
As a method of adhering to the heating element 1, hot melt adhesion (mainly (by hot pressing method). However, because the conventional needle-punch loop pile felt 4 has a backing resin layer 6 formed on the back side, there is no adhesive inside the hot melt layer 2 (usually a low-density polyethylene or ethylene vinyl acetate (EVA) film). There was a problem that the felt fibers were difficult to embed and the adhesion was poor. In order to eliminate this drawback, increasing the temperature of the hot press or increasing the time will result in loop pile (napped fibers).
There was a problem in that the tufts collapsed due to the heat of the hot press and did not return to their pilate-like appearance. In addition, in FIG. 1, 3 is a back material provided at the lower part.

(Object of the Invention) The present invention was proposed in view of the above points, and its purpose is to improve the strength, dimensional stability, and reduce weight of a needle-punch loop pile felt having a loop pile portion. To provide a method for producing needle punched loop pile felt, which makes it possible to improve hot melt adhesion and sitting comfort.

(Disclosure of the Invention) FIG. 2 shows a needle punch loop pile felt obtained according to the present invention, and the same members as in FIG. 1 are designated by the same reference numerals. The needle punch loop pile felt 4, which is connected to the heat generating part 1 through the hot melt layer 2, is made of two or more types of fibers, and the main fibers 5
For example, high melting point fibers such as nylon and polyester are used, and for others, for example, polyethylene,
This is a distinction between fibers 7 that have a low melting point and a high heat shrinkage rate, such as polypropylene. The low melting point fibers 7 are almost uniformly mixed in the high melting point main fibers 5, but are shrunk or melted so that they are hardly present on the surface side of the loop pile portion 8. The aforementioned low melting point fibers 7 are heated and melted in the base fabric portion of the needle punched loop pile felt 4, and form a bead-like mass near the intersections where the high melting point main fibers 5 are intertwined with each other. The main fibers 5 are fixed to each other by the molten material of the low melting point fibers 7, similar to the case where the conventional backing resin layer 6 as shown in FIG. 1 is formed.

Moreover, composite fibers may be used instead of the above-mentioned low melting point fibers, and these composite fibers are made by providing a low melting point resin layer on part or the entire surface of fibers with a relatively high melting point, such as polyester Using a two-layered fiber with a polyethylene or EVA layer on the outer surface of the fiber, a double layered fiber made by laminating polyester fiber and polyethylene fiber, or a modified fiber in which only the surface layer of the polyester fiber is modified to have a lower melting point. Similar to the previous method, only the low-melting layer in the base fabric of the needle-punch loop pile felt melts and the main fibers are fixed to each other.

In the present invention, as mentioned above, in the main fiber having a high melting point,
It is made by almost uniformly mixing low-melting point fibers or high-melting point and low-melting point composite fibers, and the mixing ratio is preferably 5 to 30% of the total amount of fibers. In other words, if it is less than 5%, the main fibers will not be fixed to each other, and the strength, dimensional stability, abrasion resistance, pilling resistance, and removal strength will be insufficient, and moreover, fibers with different specific gravity will be mixed. If it is less than 5%, it will be difficult to mix the hair evenly. On the other hand, if the blend ratio exceeds 30%, the strength will improve, but the felt will become hard and difficult to fold, and the melted material of low-melting fibers will become noticeable in the loop pile on the surface, which will lose its soft feel and become unsightly. This is because there are drawbacks.

In manufacturing, after mixing the wool, a loop pile is formed by needle processing from the opposite side, and then a low melting point fiber is melted in a heating process. The key point is that, as shown in Figure 3, the loop pile of low-melting point fibers 9 in the extruded loop pile 8 is heated to shrink more than the main fiber 8 to shorten the length of the pile. After this, the low melting point fibers 7 are melted by second heating. By doing this, as shown in FIG. 4, since almost no low-melting point resin adheres to the 8 portions of the loop pile (hair), a pile with a soft feel can be formed.

The second point is that, as shown in FIG.
The idea is to keep them almost separate. This is possible by layering a nonwoven fabric 10 made of low melting point fibers 7 and a felt made of main fibers 5.
If the process is then performed in the following order: integration by needle processing, and protrusion processing of the loop pile (pile) by needle processing from the opposite side, only the loop pile 8 part has almost no low melting point fibers 7, and the base fabric part has low melting point fibers. A loop pile felt 4 is formed in which the fibers 7 are mixed almost uniformly. Thereafter, by heating to melt the low melting point fibers, the main fibers can be fixed to each other. Of course, even in this case, if the two-stage heat treatment described above is performed, the effect will be greater.

The third point (not shown) is a method of mixing composite fibers. In this case, it is impossible to leave no low melting point resin in the loop pile, but since the low melting point fibers are not located alone, they will not clump together into a ball (spherical shape). This results in the loop piles being partially glued to each other. In this case, the soft feel of the pile may deteriorate to some extent, but this can be solved by changing the outer diameter of the fibers to ones that are thinner. Rather, by partially adhering the loop piles to each other, there is an advantage that a loop pile that is strong and difficult to buckle even in actual use can be formed. In addition, when we tried making a prototype using a blend of 90% polyester 15 denier main fiber and 10% modified polyester 7 denier composite fiber, we were able to make a prototype with a soft feel and a strong pile.

(Effects of the Invention) As described above, according to the present invention, (a) Since the fibers can be fixed to each other almost uniformly in the thickness direction using the low melting point resin, it does not have the comfort of sitting like a lump of conventional packing resin. Bad things can be improved. Further, no lumps of bucking resin are visible.

(b) The strength and hardness of the felt can be easily controlled by adjusting the blending ratio of low-melting point fibers.

(c) When used in electric carpets, the embedding of fibers into the hot melt layer is not hindered by the backing resin layer, so there are advantages such as improved adhesion by hot pressing and shortening of hot pressing time. There is. In addition, since it can be bonded in a short time, the restorability of the hair can also be improved.

(d) In the case of composite fibers, the piles are partially bonded to each other, so the restorability of the pile can be further improved.

It has the following effects.

[Brief explanation of drawings]

FIG. 1 is a conventional example, FIG. 2 is a partial sectional view of a needle punch loop pile felt obtained by the present invention, and FIGS. 3, 4, and 5 are explanatory views showing the manufacturing method of the present invention. . 1... Heat generating part, 2... Hot melt layer, 3...
Back material, 4... Needle punch loop pile felt, 5... Main fiber, 7... Low melting point fiber, 8...
Loop pile, 9...Loop pile of low melting point fibers, 10...Nonwoven fabric of low melting point fibers.

Claims (1)

[Claims] 1 A process of almost uniformly mixing low-melting point fibers with a mixing ratio of 5 to 30% in high-melting point main fibers or high-melting point and low-melting point composite fibers, and then forming a loop pile by needle processing from the opposite side. and then a step of thermally shrinking the low melting point fibers in the loop pile more than the main fibers by first heating to shorten the length of the loop pile, and then melting the low melting point fibers by second heating. A method for manufacturing needle punch loop pile felt for electric carpets, comprising: