JPS59164138A - Manufacture of board for formwork - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuously manufacturing formwork plates with good peelability.

Traditionally, wood boards have been used as formwork boards for concrete panels, etc., but in order to ensure that the concrete adheres to the wood boards, the wood boards are coated with a thermoplastic resin film to create a bond between the concrete and the panels. It has been proposed to facilitate peelability. For example, a method of applying adhesive to the surface of a wooden board and pasting a hot OT plastic film on it, or coating the surface of a wooden board with a thermoplastic resin film or modifying the thermoplastic resin during this process. Things are intervening
In addition, there is a method of heat contact using multi-stage plate-hot press heating and compression.

However, these methods have low productivity because the steps such as forming a thermoplastic resin film, compositing the film, applying adhesive, and heat pressing are not continuous, and the use of adhesives has a negative impact on the environment. However, with heat presses, high temperatures and pressures are safe because of the adhesive method, but they do not cause deterioration of the resin or wood board. Further, although the resulting concrete panel has good initial releasability, concrete adheres to it as the number of uses increases, and its releasability is not necessarily sufficient.

The present invention solves the above-mentioned conventional drawbacks and provides a mechanical method for efficiently and continuously manufacturing formwork plates with excellent releasability.

That is, in the present invention, a continuous wooden board is fed out, a thermoplastic resin is continuously extruded from a die in a single layer or multiple layers onto this wood board, and a silicone resin is coated on the surface of the laminated resin. The present invention relates to a method for manufacturing a formwork plate, which comprises performing a foot hardening treatment and forming the silicone resin on the surface of the vinyl laminated resin.

Examples of the wood board used in the present invention include veneer, plywood, particle board, fiberboard, etc. made of various wood materials.

Thermoplastic resins include high density, medium density and low density polyethylene, linear low density polyethylene, polypropylene, polyphthene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-propylene rubber, ethylene-butene. Polyolefin resins such as copolymers or mixtures thereof, or these polyolefin resins and unsaturated carboxylic acids or derivatives thereof, such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, iconic acid, crotonic acid, sotraconic acid, unsaturated carboxylic acids such as di-4-cyclohexene-1,2-dicarboxylic acid, endo-, bicyclo-[2,2,1]-5-hegetene-2,3-dicarboxylic acid, or acid anhydrides thereof;
Z reaction with derivatives such as esters, amides, salts, etc. to produce unsaturated carboxylic acids or their derivatives o, o o
i to 15% by weight of modified polyolefins or mixtures thereof; furthermore, polyvinyl chloride, polyvinylidene chloride, polystyrene 1/7, ABs4ft, t]L
Extrusion-moldable thermal OJ plastic resins include As resin, polyamide, polyester, polycarbonate, and polyurethane ionomer. The extrusion layer thickness of these is 20
~100μ is appropriate.

Examples of silicone resins include organosilicon polymers with siloxane bonds as the main chain, such as dimethyl poly'siloxane,
Examples include combinations of methylhydrogenborinoxane, etc., and catalysts for condensation or addition reactions (for example, acids, alkalis, amines, metal fatty acid salts, etc.).These reactions usually use thermal reaction types. However, it is also possible to use a type that is cured by ultraviolet irradiation.The composition of Nlicon yarn biased fat and reaction catalyst is usually diluted with a hydrocarbon solvent such as toluene, xylene, n-hexane, or n-heptane, and one side is cured. 0.5~1,017
It is applied to the surface of a V-shaped film or sheet in a coating amount of m2, and cured by heating at 100 to 120°C for 10 to 60 seconds. In addition to the solution type, the silicone-based and resin compositions can be used in an emulsion type, a hot melt type without using a bath medium, etc., which can be appropriately selected depending on the application or environment.

Next, the method of the present invention will be explained using the attached drawing Z.

Figure 1 is a schematic side view showing the process of the present invention. In the figure, 1 is a wooden board, and rotary veneer cut from raw wood, which will become the surface layer of veneer plywood, wood plywood, particle board, fiberboard, etc. are continuously made. Supplied. 2 is a wood board dryer,
6 is a wood board dryer, 4 is a dryer m heat machine, and 5 is an air circulation professional.A single layer or multilayer film or sheet 7 is laminated onto the dried wood board 1 from a die 6 of a resin extruder. Ru. In the case of at-, a modified polyolefin specified by AiJ, which has excellent contact strength with the main board 1, is usually used, and the wood board 1 is
Stack them so that they are in contact with. Film or sheet 7!
- The laminated wood boards 1 are further pressed together with a press/cooling roll 8 and a press roll 9, and then the silicone resin coating roll 1
0, the required amount of silicone resin 11 is applied. The method of applying the silicone resin is not limited to the roll coating method, but may also be a commonly used method, such as a knife coating method, an air knife method, or a dipping method. The silicone resin layer is dried and cured by heating in a silicone resin drier 12. 16 is a take-up machine. The wood board 1 on which the resin layer having a cured silicone resin film is laminated is cut into regular lengths by a cutting machine 14. The formwork board 16 thus obtained is conveyed by a belt conveyor 15. The veneer of the z1 plywood surface layer is wound up into a roll and sent to a pressing process.

As described above, a formwork plate having the structure as shown in the cross-sectional view of Figure 2 (al l (b)) is made with 14 holes Φ. The sheet 11' is a silicone resin layer.

As described above, according to the method of the present invention, film formation, lamination (dry lamination) of a thermoplastic resin film or sheet,
The three processes of hot pressing are reduced to one process of extrusion coating, so there is less work space, and the productivity is significantly improved, including a reduction in the number of workers, and the drying process used in manufacturing veneer plywood can also be used. The process can be streamlined. Furthermore, in the resulting board for formwork such as concrete panels, the resin penetrates into the fine details of the channels and scratches on the crystal surface, so the contact force of the resin model is strong and there is little foreign matter adhering to the surface. In addition, since a hardened resin film is formed on the resin film surface, it has excellent removability.
l K explanation.

Example 1 Maleic anhydride-modified polyethylene (acid 0.16.4%) was supplied to the extruder of lnf oil extrusion coating equipment d, and it was continuously discharged onto plywood at a die temperature of 260°C, and the discharge and Lamination to a thickness of 90 μm was performed by adjusting the take-up speed.

Furthermore, a silicone resin liquid (100 parts of Toshi Silicone Resin 25D7223, catalyst: 5R) was added onto this laminated film.
X-212o, 9 fJ, diluent solvent: ) toluene/n-
Hexane-70/30 (499.1 parts) was applied so that the silicone resin content was 0.5 g/m<2>, and dried and cured at 120 DEG C. for 50 seconds using a hot air dryer/heater.

When the obtained coated plywood was used as a concrete panel, no peeling of the film or adhesion of concrete to the panel was observed even after 100 uses.
The peelability of the concrete was good.

Furthermore, the adhesion between the veneer plywood and the modified polyethylene was stronger than that of the conventional method in which the veneer plywood and a pre-formed 90 μm modified polyethylene film were hot-pressed.

Example 2 Maleic anhydride-modified polyethylene (acid No. 16B, 1%) was used in one extrusion mode of a two-layer coextrusion lamination device, and low-gr skin polyethylene (NU0 manufactured by Nippon Unito) was used in the other extruder.
The veneer plywood was laminated and treated in the same manner as in Example 1, except that a 90μ single-layer film was extrusion laminated on the veneer plywood with the modified polyethylene side in contact with the veneer plywood.

1÷I laminated veneer plywood was used as a concrete panel, and even after 100 private use tests, there was no peeling of the film or ↑ζ of concrete on the panel, indicating that the peelability of the concrete was good. there were.

In addition, the adhesion between the plywood veneer and the collection film was stronger than that obtained by the conventional method in which the above-mentioned pre-formed temporary film and the plywood veneer were hot-pressed.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the process of the present invention on page 11,
Figures 2(a) and 2(b) are side views of the concrete panel according to the present invention. 1...Wood board, 2...Wood board dryer, 6...Wood board Expansion machine, 4...Dryer W heating machine, 5...Air circulation blower, 6...Resin extruder guide, 7,7'...Film or sheet, 8...-Cooling roll from press, ?
...Press roll. Agent: Efi Akira Agent Hagiwara Hajime -

Claims (1)

[Claims] A continuous wooden board is rolled out, and a single layer or multiple layers of hot-cold plastic IW are continuously extruded and laminated from a die onto the wooden board, and after coating the surface of the laminated resin with a resin-based resin, it is cured. 1. A method for manufacturing a formwork board, which comprises processing the silicone resin layer to form the silicone resin layer on the surface of the laminated resin.