JPS59164137A - Board for formwork having excellent exfoliating property - 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 plate for formwork with good releasability for smoothing the surface of a structural material such as concrete and preventing adhesion of structural material such as concrete to the surface of springs.

Traditionally, ifif paint or thermoplastic resin films or sheets have been applied to the surface of substrates such as plywood, particle board, and fiberboard to make it easier to separate the concrete surface from the concrete panel and to give the concrete surface a smooth finish. It is proposed that compensation be provided. Furthermore, as this film or sheet,
Attempts have been made to use a biaxially oriented polypropylene film with a smooth surface and a small coefficient of friction, or to use a film or sheet mixed with a silicone resin.

However, although the peelability of concrete panels coated with this film or sheet is improved,
A layer of concrete can be seen depending on the number of diversions, and the number of diversions is not necessarily sufficient. In particular, when a film or sheet is mixed with a silicone resin, it is difficult to mix the mixture itself, and although the releasability is improved by the movement of the silicone resin, there is a problem in that the film or sheet is easily peeled off from the substrate.

The present invention provides a plate for formwork such as a concrete panel that overcomes the drawbacks of the prior art and has good peelability.

That is, the present invention provides a releasable material in which a thermoplastic resin film or sheet is integrally layered on the surface of a wood board, and a silicone resin cured film is formed on the surface of the thermoplastic 4114 resin film or sheet. It is a good plate for formwork.

Hereinafter, regarding the removable and attractive formwork plate according to the present invention,
An example of a concrete wall will be explained with reference to FIGS. 1 and 2.

FIG. 1 is a partial cross-sectional view of a concrete panel with good peelability according to the present invention.
C Netsumachi Sosumi resin film or sheet layer 2, and silicone thread B'f on the rough surface! The hardened skin 6 is laminated and integrated. In addition, in order to strengthen the adhesion between the wood board 1 and the thermoplastic resin film or sheet layer 2, K is a film or sheet layer (172) between the wood board 1 and the thermoplastic resin film or sheet layer 2, as shown in Fig. 2. It is preferable to interpose an adhesive layer 4, for example, an adhesive modified polyolefin in the lamination of a wood board and a polyolefin-based cutter, in one of the layers.

Examples of the above-mentioned wood material &1 include boards made of various types of wood, plywood, particle board, fiberboard, and the like.

As the thermoplastic resin film or sheet layer 2,
For example, high-density, medium-density and low-density polyethylene, linear low-density polyethylene, plastic.

Liglobylene, polybutene, ethylene-propylene copolymer, ethylene-butene copolymer, ethyne-vinyl acetate copolymer, ethylene-propylene rubber, ethylene-butene rubber, etc. are polyolefin resins such as mixtures thereof, and tmi lanophor. 17 Olefin-based carbonaceous versions or derivatives thereof, such as acrylic acid, methacrylic acid, maleic acid, 7-marinated acid, itaconic acid, crotonic acid, citraconic acid, cis-4-cyclohexene-1,2-dicarboxylic acid , endo-bicyclo-(2
, 2, 1) -5-heptene-2,6-dicarboxylic acid or derivatives thereof such as acid anhydrides, esters, amides, salts, etc. Examples include modified polyolein in which 1 to 15 percent of Cl0 is added, or a mixture thereof. Furthermore, polyvinyl chloride, vinyl chloride resins such as polyvinylidene chloride, polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-
Examples include styrene resins such as styrene copolymers, polyamide resins, and polyester resins. Among these, polyolefin resins or modified podiolefins are preferred from the viewpoints of splicability and adhesiveness to wood boards. Further, the above thermoplastic resin film or sheet is used in a single layer or multiple layers of 20 to 100 μm.

The cured silicone resin film 6 formed on the surface of the thermal i'Jffi resin film or sheet is formed by adding an organic silicon-based compound having a siloxane bond as the main chain, such as dimethylpolysiloxane, methylhydrogenpolysiloxane, etc. Alternatively, it is cured by an addition reaction or a condensation reaction in combination with a catalyst for a condensation reaction (for example, a salt of an alkali, an alkali, an amine, a metal fatty acid, etc.). The reaction format is
Usually, a heat-reactive type is used, but a type that is cured by ultraviolet irradiation may also be used. The composition of silicone thread resin and reaction catalyst is usually diluted with a hydrocarbon solvent such as toluene, xylene, n-hexane, n-heptane, etc., with a coating weight of 0.6 to 1.017 tm2 on one side and 7. Apply to the surface of the film or sheet,
100-120°C, 10-60 minutes I'JJ 〃0 Heat and harden. In addition to the solution type, the silicone resin composition may be an emulsion type or a solvent-free type that does not use a solvent, depending on the application and environment! You can select and use pages.

The method for manufacturing formwork boards such as concrete panels of the present invention involves laminating a pre-formed film or sheet of the above thermoplastic resin on the surface of a wooden board, Then, after heating to a temperature above the melting point and compressing with a press or roll, apply the above silicone resin composition bath liquid onto a film or sheet and heat it to form a cured film of silicone resin, or The back side of a thermoplastic resin film or sheet on which a cured film of silicone resin has been previously formed is laminated with the front surface of a wooden board, and the two are bonded together at a temperature above the softening point or melting point of the thermoplastic resin. . The above-mentioned lamination and integration of the wood board and thermoplastic resin film or sheet and application of silicone resin can be carried out using a punch method in which each cut material is press-bonded and then a silicone resin liquid is applied, or on a continuously moving wood board. Any continuous method may be used, in which films or sheets are continuously extruded and laminated by T-die molding, and then a silicone resin liquid is continuously applied.

As described above, since the concrete panel of the present invention has good concrete peelability, no mold release agent is required, the number of times of reuse is significantly increased, and there is no need to peel off concrete adhering to the panel.

Furthermore, the surface of the concrete to be formed is smooth and does not require finishing. In addition, since the silicone-based side force is provided as a film by coating, there is no problem of mixed phase as in the case of using a silicone resin mixed film (a thermoplastic resin layer is interposed between the film and the substrate). Therefore, there is no problem with peelability from the substrate.

Next, the formwork plate having good 81I releasability according to the present invention will be explained in detail with reference to examples.

Example 1 A 12-thick plywood sheet was heated to 135°C using a hot press.
, preheated for 5 minutes, and coated with maleic anhydride-modified linear low-density polyethylene (acid 111 < 5 parts %, hereinafter referred to as modified L).
A 50μ thick biaxially oriented polyglobulene film (hereinafter referred to as OPP film) was layered on top of a 45μ thick film of LDpg), and the film was heated at a temperature of 1
65℃, pressure 1skl/7! The i:R layer was integrated by heating for 4 minutes. After the surface of the OPP film on the surface of this laminate is subjected to Nicorona discharge treatment, a silicon coating liquid (Silicon made by Toshi: 5D7223 (trade name) Ino part, catalyst; SRX
-212 (trade name) 0.9 parts, dilution solvent; toluene/
n-hexane-70730499, 1 part) was coated so that the silicone resin content was 0.517 m2, and dried and cured in a hot air oven at a temperature of 120°C for 1 minute. When this was used as a concrete panel, it showed extremely good releasability from concrete (no peeling of the film or adhesion of concrete to the panel was observed after 100 repetitions).

For comparison, a concrete panel manufactured in the same manner but without the application of silicone resin was used as a concrete panel, and after 40 repeated uses, concrete crackling was observed.

Example 2 In addition to Example 1, modification 1. Anhydrous maleic modified low density polyethylene (hereinafter referred to as modified LDPE) in place of LDPIK
, high density polyethylene (hereinafter referred to as modified HDPK), LLDP
A mixture of E and HDPR (hereinafter referred to as modified LLDPgdecamodified Hv)
pg) or ethylene-vinyl acetate copolymer (modified EV
It was produced in the same manner except that A) was used. When each was used as a concrete panel, they all had extremely good releasability from concrete, and were used for repeated use.
At 0 times, no peeling of the film or adhesion of concrete to the panel was observed.

Example 3 In Example 1, modified LDPE was used instead of modified LLDPg (thickness 45μ) and OPP film (thickness 50μ).
, modified LLDPg decamodified HDPR, modified) (DPg
Alternatively, a single-layer film of modified gVA having a thickness of 70 μm was used, and a Teflon-coated film or release paper was bundled thereon and then hot-pressed. When each was used as a concrete pile, the peelability of the concrete was extremely good (with no peeling of the film or adhesion of concrete to the pile after repeated use).

For S1 comparison, they were manufactured in the same manner except that no silicone resin was applied, and used as concrete panels for JT-iJ. Concrete adhered to each case.

Example 4 %@Example I Films of ethylene block copolymer (hereinafter referred to as modified PP blocks) each having a thickness of 70 μm were stacked on a 12-μ thick plywood board,
Temperature on veneer plywood side 155℃, modified PP crumb or PP bronc side temperature 170℃, pressure 15k)/, 4
It was produced in the same manner except that the heating layer was integrated for a minute.

When these were used as concrete panels, no peeling of the film or adhesion of concrete to the panels was observed after 100 repeated uses.

Example 5 Before the OPP films in Examples 1 and 2 and the modified polyolefin films in Examples 3 and 4 were thermally bonded and integrated with veneer plywood, the surface of each film was treated using a silimono-josou treatment device. The same silicone resin as in Example 1 was coated in an amount of 5117 m2, and dried and cured at a temperature of 120°C for 50 seconds. These films were laminated and integrated with plywood under the same conditions as in Examples 1 to 4. When each was used as a concrete panel, no peeling of the film or adhesion of concrete was observed after 100 repeated uses.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view of a concrete panel that is an example of a formwork plate with good peelability according to the present invention, and FIG. 2 is a partial cross-sectional view showing another embodiment of the formwork plate according to the present invention. It is. Agents 1) Akira’s agent Ryo Hagiwara −

Claims (1)

[Claims] Resembling wood X, consisting of a thermoplastic resin film or sheet integrally layered on the surface of the wood board, and a silicone resin cured film formed on the surface of the thermoplastic feces film or sheet, releasable. Good formwork board.