JP2902327B2 - Method for producing urethane foam and process paper for producing urethane foam therefor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process paper for producing urethane foam and a method for continuously producing blocks of urethane foam using the process paper for producing urethane foam.

[0002]

2. Description of the Related Art Various methods have been known for continuous production of urethane foam blocks that have been industrialized. A typical one is a so-called "Dracker method".

In this method, as shown in FIG. 4, a process paper 200 made of kraft paper is continuously fed on a conveyor belt 202 as a support for a bottom portion, and both side portions of the process paper 200 are fed.
After the 204 is raised and bent into a toy shape, the molten urethane resin raw material M is cast onto a support via a mix head 206. Thereafter, as shown in FIG. 5 (a), a pair of synthetic resin films 208 are provided on both sides of the bottom support 200 as urethane resin sides as side supports that can be side walls.
Is continuously fed out, and while the urethane resin raw material M is foamed and hardened in the foaming space formed by each support, the upper surface of the foam is prevented from rising according to the urethane foaming speed and has a substantially flat surface. In this case, the synthetic resin film 208 as the side support is pulled up and foamed (see FIG. 5 (b)).

[0004]

However, in the "Dracker method", since kraft paper is used as the process paper, when a urethane foaming liquid is injected, the foaming liquid permeates the process paper, There were problems such as contamination of machines such as conveyors. In order to solve this problem, it is conceivable that the process paper is composed of a synthetic resin film.
In accordance with the urethane foaming rate, it is necessary to raise the synthetic resin film 208 as a side support so as to form a substantially flat surface by preventing the foam upper surface from being raised and foaming the foam upward. is there. Therefore, if the stroke paper is made of a synthetic resin film, static electricity or the like is generated between the synthetic resin film 208, which is a side support, and the stroke paper, causing slippage. Therefore, the workability is poor and the upper surface of the foam is not flat and the quality is reduced, so that the foam cannot be used.

Therefore, it is necessary to use kraft paper as the process paper. However, when a urethane foaming liquid is injected, the foaming liquid permeates the process paper and contaminates a machine such as a conveyor. As shown in FIG. 4, the process paper 200 is peeled off from the foam and wound up, and the conveyor is soiled and the lower surface of the foam is soiled (??).
It is necessary to insert the polyethylene film again into the lower surface of the foam, and the process is complicated.

[0006] In view of the above situation, the present invention does not prevent the foaming liquid from penetrating into the process paper and contaminating machines such as conveyors when the urethane foaming liquid is injected.
In addition, according to the urethane foaming speed, the synthetic resin film serving as the side portion support can be smoothly pulled up and foamed so as to prevent the foam upper surface from rising and become a substantially flat surface. An object of the present invention is to provide a method for producing a possible urethane foam and a process paper therefor.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned objects and objects of the prior art, and the gist of the invention is as follows.
It is as follows.

(1) The adhesive strength between a base paper and a synthetic resin laminated film layer of a polyolefin or the like laminated on the base paper can be combined with urethane foam generated by foaming a polyurethane resin on the synthetic resin laminated film layer. A synthetic resin laminate layer is temporarily laminated on a base paper so as to have a smaller adhesive strength with the resin laminate film layer, and a synthetic resin laminate layer is formed on the synthetic resin laminate film layer from the polyurethane resin to be foamed. A process paper for producing urethane foam, wherein the process paper for releasable is provided, and a synthetic resin laminate film layer missing portion is provided on both side portions thereof.

(2) A method for producing a urethane foam, comprising a two-layer release paper in which a synthetic resin laminate film layer is temporarily adhered releasably to paper as a support for the bottom, and both side portions thereof The continuous process paper for urethane foam production having a synthetic resin laminated film layer missing portion on the conveyor belt is continuously bent so that the synthetic resin laminated film layer surface faces inward, and both side portions are raised and bent. A step of casting a urethane resin raw material onto the support, a step of continuously forming a pair of synthetic resin films on both sides of the urethane resin side of the bottom support as side supports that can be side walls. In accordance with the urethane foaming speed, the urethane resin raw material is foamed and cured in the foaming space formed by each support. A step of pulling up the side support in an upward direction so as to prevent the top surface of the foam from rising and becoming a substantially flat surface, and a step of peeling and winding only the paper from the bottom support. A method for producing a urethane foam.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a partially enlarged cross-sectional view of a process paper for producing urethane foam according to the present invention.

In FIG. 1, reference numeral 1 denotes a process paper for producing a urethane foam of the present invention as a whole. The process paper for producing a urethane foam 1 is basically formed of a very thin synthetic resin on a base paper 2. The laminated film layer 3 is formed by laminating.

The urethane foam-producing process paper 1 has a urethane foam in which the adhesive strength between the base paper 2 and the synthetic resin laminate film layer 3 is generated by foaming a polyurethane resin on the synthetic resin laminate film layer 3. The synthetic resin laminate layer is temporarily laminated on the base paper 2 so as to be smaller than the adhesive strength between the synthetic resin laminate film layer 3 and the synthetic resin laminate film layer 3.

Further, process paper 1 for producing urethane foam
Then, as described later, when manufacturing urethane foam, it is used as a support for the bottom part, while continuously feeding out on a conveyor belt, both sides are raised and bent to form a toy shape. In this case, the synthetic resin laminate film layer lacking portion 4 is provided on both side portions corresponding to the rising portions. The width of both side portions is preferably about 600 to 650 mm from the viewpoint of improving the sliding of the suspended side film.

The base paper 2 is made of kraft paper, high-quality liner, or the like.
Although it is preferably about 50 to 200 g / m ² , the synthetic resin laminated film layer 3 is preferably made of polyolefin. For example, polyethylene and polypropylene can be used. ~
A thickness of about 30 μm is good.

The process paper of the present invention can be obtained by extruding and laminating polyethylene on the base paper 2 at about 240 ° C., as disclosed in JP-B-54-20227. This is because when the extrusion temperature is as high as about 300 ° C., for example, the resin laminate film layer 3 is completely adhered to the base paper 2 while the extrusion temperature is about 170 ° C.
If it is relatively low, there is a problem in the extrudability of the resin, considering the extrudability of the resin and the temporary adhesion at each temperature, about 230
This is because the best case is around ° C.

A method for producing a urethane foam using the process paper of the present invention configured as described above will be described with reference to FIGS.

FIG. 2 is a schematic view showing the entire process of the method for producing a urethane foam using the process paper of the present invention, and FIG.
FIG. 3 is a cross-sectional view illustrating the foaming space.

First, as shown in FIG. 2, the process paper 100 of the present invention having the above-described structure as a bottom support is continuously fed onto a conveyor belt 102 while its both side portions 104 (synthetic resin). The portion corresponding to the laminated film layer missing portion 4) rises and bends into a toy shape (FIG.
3 (a)), the molten urethane resin raw material M is cast on a support through a mix head 106.

Thereafter, as shown in FIG. 2, a pair of synthetic resin films 108 are continuously fed out on both sides of the bottom support 100 as urethane resin sides as side supports which can be side walls. While the urethane resin raw material M is foamed and hardened in the foaming space formed by the support, the upper surface of the foam is prevented from rising according to the urethane foaming speed so that the foam upper surface becomes a substantially flat surface. The synthetic resin film 108 as a support is pulled up and foamed (see FIG. 3 (b)).

In this case, according to the urethane foaming rate, the synthetic resin film 108 serving as a side support is pulled upward so as to prevent the upper surface of the foam from rising and to become a substantially flat surface. However, if the process paper of the present invention is used, both side portions 104 (portions corresponding to the synthetic resin laminated film layer missing portions 4) become portions that come into contact with the synthetic resin film 108. Static electricity is not generated between the synthetic resin film 208, which is a support, and the process paper, and slippage is not deteriorated. The synthetic resin film 108 can be pulled up smoothly, so that workability is good and foaming is performed. The upper surface of the body becomes flat and the quality is constant.
Also, when the urethane foaming liquid is injected, the bottom support
Since a synthetic resin laminate is formed on the bottom portion 101 of the base 100, the foaming liquid does not permeate the travel paper, so that a machine such as a conveyor is not contaminated.

After foaming, after foaming,
As shown in FIG. 2, only the paper of the process paper 100 is peeled off from the foam (the portion where the synthetic resin is laminated is left on the foam side) and wound up by the winding roll 110. I have. In addition, the film on the side is wound up,
It does not remain in the foam.

Further, since the thus obtained urethane foam has an unreacted portion remaining, it is stored for a predetermined time on a shelf of an aging chamber (not shown) in order to complete the reaction, and After being cut into dimensions, the product is shipped.

[0024]

EXAMPLE 1 Polyethylene ("NUC8009", Nippon Yunika Co., Ltd., and "NUC8075") were placed on the top surface of kraft paper (75 g / m ² ) as a base paper.
), 50:50 (weight ratio) blended with Nippon Yunika Co., Ltd.
Extrusion was performed at 0 ° C. to form a 15 μm-thick polyethylene film layer on the base paper to obtain process paper A of the present invention.

On the other hand, kraft paper (75 g / m ² ) is used as the base paper.
A polyethylene film layer having a thickness of 15 μm was formed on the base paper by extruding polyethylene at 240 ° C. using a well-known melt extrusion method to obtain a conventional process paper B.

Example 2 A urethane foam block C was obtained on the basis of the urethane foam production method of the present invention, using the process paper A as an upper support. Incidentally, a CPP film (30 μm) was used as the side film.

A urethane foam block D was obtained by using a conventional process paper B as a bottom support, based on a conventional urethane foam production method.

Then, the urethane foam block C and the urethane foam block D were compared. As a result, the process paper for urethane foam production of the present invention, and the urethane foam block C obtained by the method for producing a urethane foam using the process paper have much better shape, shape and product loss. Was.

[0029]

According to the urethane foam manufacturing process paper and the urethane foam manufacturing method using the same according to the present invention constituted as described above, (1) when the urethane foaming liquid is injected, the bottom support Since the synthetic resin laminate is formed on the bottom part of the body, the foaming liquid does not permeate the stroke paper and does not contaminate a machine such as a conveyor.

(2) Since the synthetic resin laminated film layer lacking portions on both side portions become portions that come into contact with the synthetic resin film, static electricity or the like is generated between the synthetic resin film and the travel paper, and slippage is deteriorated. Without, according to the urethane foaming speed, the synthetic resin film as the side support is smoothly pulled up in the upward direction so that the foam upper surface is prevented from rising and becomes a substantially flat surface. Foaming is possible, workability is good, and the top surface of the foam is flat and the quality is constant.

(3) Since the inside of the furnace is not contaminated, the temperature of the conveyor is stabilized.

[Brief description of the drawings]

FIG. 1 is a partially enlarged cross-sectional view of a process paper for producing urethane foam of the present invention.

FIG. 2 is a schematic view showing the entire process of a method for producing a urethane foam using the process paper of the present invention.

FIG. 3 is a cross-sectional view illustrating a foaming space.

FIG. 4 is a cross-sectional view schematically showing a main part of a conventional method for producing a urethane foam.

FIG. 5 is a cross-sectional view illustrating the foaming space of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Process paper for urethane foam manufacturing 2 ... Base paper 3 ... Synthetic resin laminated film layer 4 ... Synthetic resin laminated film layer missing part 100 ... Process paper 101 ... Bottom part 102 ... Conveyor belt 104 ... Both side parts 106 ... Mix head 108 ... Synthetic resin film 110 ... Winding roll 200 ... Process paper 202 ... Conveyor belt 204 ... Both sides 206 ... Mix head 208 ... Synthetic resin film M ... Urethane resin raw material

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI // B29K 23:00 75:00 105: 04 B29L 9:00

Claims (2)

(57) [Claims] An urethane foam and a synthetic resin having an adhesive strength between a base paper and a synthetic resin laminate film layer of a polyolefin or the like laminated on the base paper are formed by foaming a polyurethane resin on the synthetic resin laminate film layer. The synthetic resin laminate layer is temporarily laminated on the base paper so that the adhesive strength with the laminate film layer is smaller, and the synthetic resin laminate layer is formed from the polyurethane resin to be foamed on the synthetic resin laminate film layer. A process paper for producing urethane foam, which is configured to be releasable, wherein a synthetic resin laminate film layer missing portion is provided on both side portions thereof. 2. A method for producing a urethane foam, comprising:
(1) A urethane foam which is composed of a two-layer release paper in which a synthetic resin laminate film layer is temporarily adhered to paper so as to be peelable and has a synthetic resin laminate film layer missing portion on both sides thereof as a support for the bottom. A process in which the manufacturing process paper is continuously fed out onto a conveyor belt such that the synthetic resin laminated film layer surface faces inward, and both sides are raised and bent to form a toy shape.
(2) a step of casting a urethane resin raw material on the support; (3) a step of forming a urethane resin on both sides of the bottom support;
A step of continuously feeding a pair of synthetic resin films as side supports that can be side walls; (4) foaming and curing the urethane resin raw material in the foaming space formed by each support while maintaining the urethane foaming speed. In response, the step of pulling up the side support body upward so as to prevent the top surface of the foam from rising and becoming a substantially flat surface, (5) peeling only the paper from the support body for the bottom part A method for producing urethane foam, comprising a step of winding.