JPS6253820A - Manufacture of sheet molded article - Google Patents

Abstract

PURPOSE:To improve production efficiency, by a method wherein a foamed sheet on the surface of which a powdery adhesive agent has been sprayed is piled upon nonwoven fabric, through holes are formed in the sheet by thrusting the same with thrusting needles, and lamination through adhesion is performed by laminating the sheet and nonwoven fabric temporarily, softening them through heating and performing press molding of them. CONSTITUTION:As for a spraying part 2 of an adhesive agent on a running route of a foamed sheet S, a powdery thermal-adhesion adhesive agent is sprayed on the top of the foamed sheet S. Then unwoven fabric F which has been pulled out by a supply part 3 is made to run by piling the same upon the top of the foamed sheet S to which the adhesive agent has been sprayed. On the way of the running the foamed sheet S and an unwoven fabric F are sewn on each other by thrusting them with needles 40 and are laminated temporarily by low joining force along with boring of a large number of needle-shaped small through holes in the whole surface of the foamed sheet S by thrusting it with the thrusting needles 40 implanted on the external surface of a roll 4 provided with needles. Then a temporary laminated sheet is molded by molding tools 60, 61 by heating the same through a heating part 5. Simultaneously with this molding the needle-shaped through holes are deformed through expansion and through holes larger than original ones are formed.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to a method for manufacturing a sheet molded product, and more specifically, it relates to a method for producing a sheet molded product, and more specifically, a foamed sheet with through holes for ventilation and water passage formed therein and a nonwoven fabric are layered, and the product is used for packaging fruits. This article relates to a method for manufacturing sheet molded products used for trays, etc.

<Prior art> The demand for sheet molded products made by laminating a foamed sheet with through holes and a nonwoven fabric as described above is increasing as it is suitable as a lay for wrapping fruits.
There is a prior art disclosed in Publication No. 50 and the like.

In addition, compared to the conventional 1-lay packaging made of a single foam sheet, the above-mentioned packaging tray can better absorb moisture emitted from fruits and condensation water generated during cooling storage due to the high water absorption of the nonwoven fabric. The soft texture of the non-woven fabric prevents deterioration and deterioration of quality due to the appearance and impact of fruit, and the soft texture of the non-woven fabric gives it a luxurious appearance. In addition, the through holes formed in the foam sheet act as water holes to drain the moisture absorbed by the nonwoven fabric to the bottom of the tray, leaving moisture on the fruit and causing deterioration of the fruit. It is particularly effective for packaging high-quality fruits that are easily perishable and require heavy protection, as it acts as a ventilation hole for the underside of the fruit and maintains the quality of the fruit. It is suitable.

In order to manufacture a sheet molded product in which a foam sheet with shell holes and a nonwoven fabric are laminated as described above, there is a step of punching through holes in the foam sheet, and a step of bonding the foam sheet and the nonwoven fabric with an adhesive. This requires a process of manufacturing a laminated sheet, and a process of molding the laminated sheet into a tray shape or the like by thermoforming.

Conventionally, each of the above processes was performed separately, which required the effort of storing intermediate products and attaching and detaching intermediate products to and from the manufacturing equipment for each process each time each process was completed, resulting in improved manufacturing efficiency. However, there was a problem in that the cost was high.

In particular, in order to normally laminate foam sheets and nonwoven fabrics, they are bonded by heating with a thermal adhesive, which requires time and effort to heat the foam sheets and adhesives to the bonding temperature, and the laminated sheet after thermal bonding is If the material is not sufficiently cured until it is cooled and hardened, handling and subsequent press forming cannot be performed, and this lamination process has become a problem that hinders the efficiency of the entire manufacturing operation.

Therefore, the purpose of the present invention is to solve the problems of the above-mentioned prior art, and to improve the manufacturing process of a sheet molded product in which a foamed sheet with through holes and a nonwoven fabric are laminated, in particular, to solve the problems of the prior art described above. The object of the present invention is to develop a manufacturing method that can improve the M layer process, carry out the entire manufacturing process continuously and efficiently, and improve manufacturing efficiency.

A method for achieving the above object is a method of manufacturing a sheet molded product in which a foamed sheet with through holes and a nonwoven fabric are laminated, and the surface of the foamed sheet is coated with a powdery heat-adhesive material. After spraying the adhesive, the foam sheet and non-woven fabric are overlapped, and a piercing needle is used to pierce the folded foam sheet and non-woven fabric to form through-holes in the foam sheet, and at the same time, the foam sheet and non-woven fabric are temporarily laminated. Next, the temporary laminated sheet is heated and softened, and then press-molded using a pair of male and female press molds, and at the same time, the foamed sheet and the nonwoven fabric are adhesively laminated by the action of a thermal adhesive.

<Example> Next, an example of the present invention will be described below with reference to the drawings.

FIG. 1 shows the overall structure of the manufacturing equipment used to carry out the method of the present invention, and (1) is a supply section for the foam sheet (S), in which a long foam sheet (S) is supplied in advance. The wound sheet is held and the foamed sheet (S) is pulled out in sequence from the end and run in a fixed direction. In addition, for the traveling of the foam sheet (S), a traveling mechanism such as a crank chain, a conveyor belt, and a transport roll, which are used in ordinary continuous molding equipment for foam sheets, etc., is provided, but detailed illustrations are omitted. are doing.

J on the travel path of the foam sheet (S) following the supply section (1)
3, (2) is the adhesive dispersion part, and the foam sheet (
Powdered heat-adhesive adhesive can be sprayed onto the upper surface of S).

(3) is a supply unit for non-woven fabric (F), which holds a roll of long non-woven fabric (F). agent was sprayed,
It is superimposed on the upper surface of the foam sheet (S) and run.

Next, (4) is a rotating roll with nails, and a large number of piercing needles (40) are implanted on the outer surface of the cylindrical roll.
As described above, the laminated foam sheet (S) and nonwoven fabric (F) are run along the nailed rotating roll (2) with an adhesive in between.
S) with the puncture needle (40) and insert the foam sheet (
By punching a large number of small needle-like through holes on the entire surface of S), and simultaneously piercing the foam sheet (S) and the nonwoven fabric ([) with a needle (40) and sewing them together, The temporary V4 layer is formed with a relatively weak bonding force that does not allow the two layers to separate easily.

That is, at this stage, the powder adhesive does not work at all, so the foam sheet (S) and the nonwoven fabric (') are not completely laminated, but during the running or working process in the later stage, The foam sheet (S) and the nonwoven fabric ([) are temporarily laminated with a bonding force that does not separate them.

In addition, in the illustrated device, in order to ensure a sufficient contact length between the nailed rotating roll (4) and the foam sheet (S), the foam sheet (S), which had been running horizontally until the previous stage, is moved diagonally downward. The winding angle with respect to the 11" rotating roll (4) is widened by changing the direction to the side.

Next, (5) is a heating section, which is a heating furnace with a built-in electric heater, etc., and the temporary laminated sheet consisting of the foam sheet (S) and the nonwoven fabric (") as described above is heated in the heating section (5). )
The foam sheet (S) and nonwoven fabric ('') are heated with
At the same time as heating to a molding temperature that allows thermoforming, the powdered thermoadhesive adhesive is heated so that it can exhibit adhesive action.

Next, the heated temporary laminated sheet enters the molding section (6), is pressed between a pair of upper and lower male and female molds (60) (61), and is simultaneously press-molded into a predetermined molded product shape. , the foam sheet (S) and the nonwoven fabric (") are pressed tightly and are completely adhesively laminated by the action of the thermal adhesive interposed in between. The existing needle-shaped through hole was expanded and deformed at the same time as the press molding, resulting in a much larger through hole than originally.

After the above process, 1. After the rimming process and cutting process,
Sheet molded products such as veneer-shaped packaging trays are completed.

Therefore, according to the illustrated manufacturing apparatus, the supply section (1) and the J
: If the foam sheet (S) and the nonwoven fabric (F) are supplied to (3), the foam sheet (S) and the nonwoven fabric ('')
While running continuously, the manufacturing process of the sheet molded product is sequentially passed through.

FIG. 2 shows a tray (T) for packaging fruits, which is an example of the manufactured sheet molded product. ] - The lei (T) is formed with a storage recess (A) that roughly corresponds to the shape of the lower half of the fruit, and a nonwoven fabric (") is placed on the top side that comes into direct contact with the fruit, and a nonwoven fabric (") is placed on the bottom side. is a foam sheet (S
) is placed. In addition, the through holes (h) formed in the foam sheet (S) have a relatively large hole shape that expands at the same time as it is stretched along the stretching direction of the foam sheet (S) during molding. ing.

Among the methods for manufacturing sheet molded products described above, the foamed seams I to (S) are foams made of polystyrene, polyethylene, polypropylene, and other various thermoplastic resins that are used in ordinary sheet molded products. A sheet can be used, and it is also possible to use one in which a plurality of foamed sheet materials are laminated, or one in which a non-foamed synthetic resin film is laminated on a foamed sheet (S).

Further, as the nonwoven fabric (F), one made of ordinary synthetic fibers or natural fibers can be used, but one made of rayon fiber is particularly suitable because it has excellent water absorbency.

Furthermore, as the powdered thermal adhesive, adhesives such as vinyl acetate resin adhesives that are commonly used for bonding foam sheets and nonwoven fabrics can be used.

Next, as the needle guide rotating roll (4), a relatively large-diameter roll is suitable because it can ensure a long contact length with the foam sheet (S)'8. In addition, the shape and implantation density of the piercing needles (40) may vary depending on the use of the sheet molded product to be manufactured.
It may be set by considering the required water permeability and air permeability.

Also, regarding the structure of the heating section (5) and molding section (6),
The same type of conventional sheet forming equipment is used, but as the forming part (6), through-holes are formed in the foamed sheet (s), and the material itself of the nonwoven fabric (") has air permeability. Therefore, it is difficult to form a sheet by vacuum forming or pressure forming, but forming is possible by employing press forming using a pair of molds 11a (60) and (61).

Note that the fruit packaging tray (T) shown in the figure is the most effective sheet molded product produced by the method of the present invention, but other types of packaging trays, packaging frames, packaging containers, etc. It can also be applied to sheet molded products used as packaging materials, heat-insulating and sound-absorbing materials for construction, interior materials for housing, etc.

Effect> According to the method for manufacturing a sheet molded product of the present invention configured as described above, after spraying a powdery heat-adhesive adhesive on the surface of a foamed sheet (S), the foamed sheet (S) is layered with a nonwoven fabric (S). At the same time, forming through holes in the foam sheet (S) with a piercing needle (40), temporarily laminating the foam sheet (S) and the nonwoven fabric (F), and heating the temporary V4 layer sheet, followed by press molding. At the same time, the foamed sheet (S) and nonwoven fabric (F) are completely bonded and laminated by the action of a thermal adhesive to complete the sheet molded product, which is continuously carried out on a series of production lines. By being able to do this, sheet molded products can be manufactured extremely efficiently and manufacturing costs can be reduced.

That is, the step of forming through holes in the foam sheet (S), the step of thermally adhering the foam sheet (S) and the nonwoven fabric ([) to produce a laminated sheet, and the hot press molding step are carried out sequentially and independently. In the conventional method, good press molding cannot be achieved unless sufficient time is allowed for the adhesive to cool and harden between the laminating process and the pressing process, and foaming occurs twice in the laminating process and pressing process. It takes time and effort to heat and cool the sheet (S), etc., which greatly hinders the improvement of work efficiency, and also requires double heating equipment, resulting in high equipment and manufacturing costs.However, this invention method By performing the adhesive lamination process and press molding process of the foam sheet (S) and nonwoven fabric (F) at the same time, heating of the foam sheet (S), etc. can be done only once, and the press can also be used as heating equipment. It is only necessary to provide the heating section (9) for molding, making it extremely simple, improving the manufacturing efficiency of sheet molded products, and reducing equipment costs.
This is highly effective in reducing manufacturing costs.

Moreover, the foam sheet (
At the same time as forming the through holes for S), the foam sheet (S)
The foam sheet (S) and the non-woven fabric (F) are temporarily laminated and transported to the heating and press forming process.
) is not completely laminated, it is easy to handle, and when traveling on transport rolls or conveyors,
) and the nonwoven fabric (F) do not come loose or separate, and can be handled reliably while being stacked until press molding.

In addition, a powdered adhesive is used as a thermal adhesive to bond the foam sheet (S゛) and the nonwoven fabric ('').
) and the non-woven fabric (F), and since it is a powder adhesive, it may be absorbed by the non-woven fabric (F) like a liquid adhesive, or flow. Or,
There is no fear of leakage outside the temporary 111-layer sheet, and the adhesive action can be achieved reliably during the press molding process.

Therefore, according to the method of this invention, while continuously running the foam sheet (S) or nonwoven fabric (F) as long as it is,
This is an excellent method that allows each step to be performed in sequence, making it possible to manufacture sheet molded products extremely efficiently, and greatly contributing to reducing equipment costs and manufacturing costs.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a schematic structural diagram of a manufacturing apparatus, and FIG. 2 is a perspective view of important parts showing dimensions of an example of a manufactured sheet molded product. (2)...Adhesive part, (4)...Rotating roll with nails, (5)...Heating part, (6)...
・・Molding part, (S) ・・Foam sheet, (F)・
...Nonwoven fabric. Patent applicant Sekisui Plastics Co., Ltd. Nippon Osbunny Kako Co., Ltd.

Claims (1)

[Claims] 1. Laminated foam sheet with through holes and nonwoven fabric This is a method for manufacturing sheet molded products. So, powdered thermal adhesive is applied to the surface of the foam sheet. After spraying the adhesive, attach the foam sheet and the adhesive. Overlap the woven fabric and use a piercing needle to Poke the foam sheet and nonwoven fabric together. Puncture and form through holes in the foam sheet. At the same time, the foam sheet and nonwoven fabric are temporarily laminated. Then, the temporarily laminated sheet is heated and softened. After forming, press with a pair of male and female press molds. At the same time, foam sheets and non-woven Laminated with cloth using thermal adhesive. Manufacture of sheet molded products characterized by Construction method.