JPS6323305B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a laminate made of fibrous materials. Conventionally, methods for manufacturing this type of laminate are disclosed in, for example, Japanese Patent Publication No. 44-4876 or Japanese Patent Publication No. 44-4878.
As shown in the publication, granular solid adhesive, which is a thermosetting synthetic resin, is mixed with fiber material made from defibrated cut cloth, etc., and after this is formed into a plate shape, the solid adhesive is melted and solidified using heated air. What causes it is already known. However, in the laminates produced by this method, the molten adhesive cannot wrap around the fibers sufficiently and the bonding range (area) is narrow, resulting in poor elasticity of the fibers themselves, and the bonding strength between the fibers is low. It has the disadvantage that it becomes weak and lacks resilience against compressive loads, or results in large permanent deformation when compressive loads are repeatedly applied. Also, JP-A-54-106678, JP-A-54-
Publication No. 134178, etc. discloses that adhesive binders such as melamine, urea, phenol, or diammonium phosphate salts are attached between fibers by spraying or dipping, and then heated and the solvent is removed. Although a method for manufacturing felt is disclosed in which the felt is solidified by vaporizing the solvent, sufficient elasticity could not be obtained with the conventional method of vaporizing and solidifying the solvent by heating. The present invention was made to solve this problem, and its main purpose is to obtain at a low cost a fiber laminate with improved elasticity and low permanent deformation. In order to achieve this objective, the manufacturing method of the present invention involves uniformly wetting the surface layer of a single filament of a fiber material, such as a fiber or cut cloth, until it can exhibit elasticity by wetting the surface layer of a single filament with a liquid adhesive. After that, this is made into a laminate of a desired thickness, and the liquid adhesive is solidified by the action of high temperature steam. An embodiment of the present invention will be described below with reference to the drawings. The figure shows a flow sheet of the manufacturing method according to the present invention, and in the figure, 1 is a hopper feeder, 2 is a mixer provided to communicate with the hopper feeder, 3 is a suction fan provided between them, and 4 is connected to the mixer. A tank for liquid adhesive, 5 a conveyor disposed below the outlet of the mixer 2, 6
7 is a fleece manufacturing device provided on the discharge side of the transport conveyor; 7 is a defibrating cylinder provided within the fleece manufacturing device and having a large number of needle teeth protruding from its outer periphery;
Reference numerals 8 and 8 denote a pair of rotating mesh cylinders for making the defibrated fiber material into a plate shape, 9 a heating device disposed on the exit side of the fleece manufacturing device, and 10 a superheated steam blowing pipe piped inside the heating device. , 11 is a conveyor disposed within the heating device and on the exit side; 1
2 indicates a cutter. According to the present invention, a fibrous material such as cut cloth is put into the hopper feeder 1, finely combed by a mechanism within the hopper feeder, and then transferred to the mixer 2. Inside the mixer, the liquid adhesive is dripped while rotating the stirring blade. As the liquid adhesive, a wet heat curing urethane adhesive resin is used, and the amount added is about 10 to 30 parts per 100 parts of the fiber material in the mixer. In this way, the liquid adhesive is uniformly applied to the surface of the fibrous material in the mixer to an appropriate degree of wetting. Next, this fibrous material is transferred to a fleece manufacturing device 6 by a conveyor 5. In the fleece manufacturing equipment, a defibration cylinder 7 is used.
The fibrous material is defibrated into finer pieces and passed through the rotating mesh cylinders 8, 8 to form a plate having a predetermined thickness. This plate-shaped fibrous material is then sprayed with superheated steam within a device on a transport conveyor 11 to solidify the liquid adhesive in the fibrous material, and then passed through a heating device 9 to dry. The fiber material that has passed through the heating device is cut to a predetermined thickness by a cutter 12. The characteristics of the fiber laminate produced in this way (product of the present invention) and conventional product A were compared, and the test data is shown in the following table. Here, the conventional product A refers to a product formed by mixing a granular solid thermoplastic or thermosetting resin adhesive with a fibrous material, which has already been described as a conventional example. Note that the test method is based on JIS, and detailed explanation thereof will be omitted.

【table】

[Table] From the table, it can be seen that the product of the present invention has a lower apparent density, a higher rebound modulus, and a lower permanent set due to repeated compression than the conventional product A. Here, a low apparent density means that the material is lightweight as long as it has the same thickness, length, and width. The fact that the product of the present invention has such a low apparent density means that even if the amount of fiber used is reduced due to the use of an elastic adhesive, performance superior to that of conventional products can be obtained. In addition, the high rebound elasticity is due to
Unlike point-bonded powder adhesives, the adhesive is applied to the entire periphery of the fiber material itself, which increases its elasticity, and the bonding area between the fiber materials is large, which increases the bonding strength. This is due to an increase in Furthermore, the reason why the permanent deformation is small is that as a result of the increase in the bonding strength between the fiber materials as described above, the ability to recover from deformation is increased. In addition, it has high air permeability, excellent moisture absorption and air permeability, and when the product of the present invention is used as an automobile seat, it provides a comfortable ride that is not found in urethane foam products. Further, although not shown in the table, sound absorption properties were investigated as another property test, and it was found that the product of the present invention had the best sound absorption performance. As explained in the examples above, according to the manufacturing method of the present invention, a fiber laminate having excellent elasticity and low permanent deformation can be obtained. The laminate is also lightweight and has excellent sound and moisture absorption properties, so it is expected that it can be used in a variety of applications, such as cushion parts such as mats and automobile interior parts, depending on the individual characteristics. can. Another major feature is that, unlike conventional urethane products, it can be manufactured at a low cost because it uses waste fibers such as cut cloth.

[Brief explanation of the drawing]

FIG. 1 is a manufacturing flow sheet shown to explain the manufacturing method according to the present invention.

Claims (1)

[Claims] 1. After finely defibrating fibrous materials such as fibers and cut cloth, drop a moist heat-curable urethane liquid adhesive at a ratio of 10 to 30 parts per 100 parts of the fibrous material and mix with stirring. The surface layer of each single fiber of the fibrous material is moderately and uniformly moistened with the liquid adhesive, and then the fibrous material is further finely defibrated using a defibrating cylinder having a number of needle teeth protruding from the outer periphery. Production of a fiber laminate characterized in that the fiber laminate is laminated into a plate shape of a predetermined thickness, and then high-temperature steam is infiltrated into the laminate to solidify the liquid adhesive, thereby making it highly elastic and uniformly bulky. Method.