JPS6151990B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a whiteboard and a method for manufacturing the same.

There are five types of whiteboards available on the market:
It is broadly divided into species.

(1) Enamel type (2) Film overlay type (3) Baked steel type (4) Thermosetting resin laminated pressing type (5) Polyester decorative board type However, all of these types of whiteboards are There are drawbacks as mentioned.

(1) Enamel type This type has a white enamel finish on the surface of the metal plate, so the surface performance of the whiteboard is very good.
The drawback is that the processing cost is extremely high. Also,
Since enamel is inorganic, it has extremely low flexibility and low impact resistance, so even though the base material is a metal plate, it cannot be bent, which is a feature of metal plates, and as a result, the final product cannot be processed. However, there is a disadvantage in that it requires complicated and extra effort to attach the frame, attach various parts and members, and assemble the necessary parts. Furthermore, in terms of dimensions, defects such as distortion, warping, and twisting are likely to appear due to the limitations of the enamel baking furnace and the negative characteristics of enamel, making it extremely difficult to manufacture whiteboards with a length of 6,000 mm or more. Of course, in practice, enameling a thin iron plate of 50 to 150 microns causes warping, twisting, and distortion, making it impossible to produce as a commercial product.

(2) Film overlay type This type of whiteboard uses a white film made of acrylic, nylon, polycarbonate, polypropylene, etc. as the overlay material, but these film types are easily scratched. In addition, ink marks from markers, which are the most important performance requirement for whiteboards, tend to remain on the board surface, resulting in severe stains and poor functionality as a whiteboard.

(3) Baked steel plate type This type is commercially available as a variety of colored steel plates such as polyester, acrylic, melamine, vinyl chloride sol, diallyl phthalate, etc., and some of these are used as whiteboards. , this type of whiteboard has marker ink residue, so it is not recommended for young children.
Although it is commercially available as an inexpensive whiteboard for children, there is no evaluation of its value as a large-sized product for commercial use. In addition, there are processed products made of aluminum and stainless steel on the market, but using non-magnetic materials like these does not satisfy another performance requirement for whiteboards, which is the ability to attach magnets. There is a drawback that it cannot be done.

(4) Thermosetting resin laminated pressing type This type has the drawback of having the largest marker ink residue and low commercial value compared to the film overlay type and the steel plate baking type.

(5) Polyester decorative board type This type is made of titanium base paper or thin paper processed with resin, so pinholes and air bubbles are built into the coating film, and marker ink remains on the board surface in spots. However, there are drawbacks that significantly reduce the product value.

Furthermore, there was a drawback that it was not possible to bend at right angles using the V-cut method, or to bend an arc of 5R or less using the R-cut method.

SUMMARY OF THE INVENTION An object of the present invention is to provide a whiteboard and a method for manufacturing the same, which can improve the problem of marker ink residue, can be easily manufactured in any size and color, and can be easily bent.

The whiteboard according to the present invention includes a thin iron plate of about 50 to 150 microns, paper such as parchment paper, tracing paper, glassine paper, liner paper, or latex-impregnated paper adhered to the surface, and an isocyanate group on the surface. and an unsaturated polyester resin layer adhered via a primer having the following properties.

The method for manufacturing a whiteboard according to the present invention comprises approximately
Paper such as parchment paper, tracing paper, glassine paper, liner paper, or latex-impregnated paper is adhered to the surface of a thin iron plate of 50 to 150 microns, and an unsaturated polyester resin layer is applied on top of it via a primer having an isocyanate group. It is characterized in that it is formed by a wet film method.

Embodiments of the present invention will be described in detail below with reference to the drawings. As shown in FIG. 1, the whiteboard 1 of this embodiment has a zinc thin iron plate 2 of approximately 50 to 150 microns.
and paper (including synthetic paper) 4 such as parchment paper, tracing paper, glassine paper, liner paper, or latex-impregnated paper, whose surface is bonded via a polyethylene film adhesive 3 treated with urethane. It consists of an unsaturated polyester resin layer 6 adhered to its surface via a moisture-curable urethane primer 5 having an isocyanate group.

Such a whiteboard 1 is manufactured as follows. Paper 4 such as parchment paper, tracing paper, glassine paper, liner paper, or latex paper is processed by endless heat and pressure using a polyethylene film adhesive 3 that has been treated with urethane on the surface of a thin galvanized iron plate 2 of approximately 50 to 150 microns. Laminate.
A moisture-curable urethane primer 5 having an isocyanate group is roll coated thereon. After that, we applied a clear or pigmented unsaturated polyester resin using a wet film method, taking into account the timing when the reactive group of the isocyanate could be utilized, and solidified it with a ridged or half-lined surface without any irregularities. An unsaturated polyester resin layer 6 is obtained.

Such a whiteboard 1 is made of zinc thin iron plate 2
A paper 4 containing almost no air bubbles such as parchment paper, tracing paper, glassine paper, liner paper or latex paper is adhered to the paper, and an unsaturated polyester resin layer 6 is applied thereon via a primer 5 using a wet film method. Since the unsaturated polyester resin layer 6 is formed, no heat and pressure is applied when forming the unsaturated polyester resin layer 6, and air bubbles do not rise from the paper layer below it. 6 can be suppressed as much as possible from remaining in the air bubbles and pinholes. As a result, the problem of marker ink residue, which is the most important performance for a whiteboard, can be significantly improved. In addition, since the paper 4 and the unsaturated polyester resin layer 6 are bonded via the primer 5 having an isocyanate group, the isocyanate group (NCO-) is bonded to the hydroxyl group (OH-) in the paper 4 and the unsaturated Hydroxyl groups (OH
-), it was possible to obtain an adhesive strength of 7 kg/cm ² or more. In this case, parchment paper, tracing paper, glassine paper, liner paper, latex-impregnated paper, etc. are used as the underlying paper 4, so these papers 4 have strong interlaminar strength and contribute to improving adhesive strength. It is possible to
The elasticity of the paper 4 is extremely effective in preventing cracks, cracks, etc. that are likely to occur during V-cutting or R-cutting.

In addition, in the present invention, since the thickness of the iron plate 2 as a base material is approximately 50 to 150 microns, the whiteboard 1 can be bent at right angles using the V cut method or arcuately bent using the R cut method. It can be done easily. If the thickness of the iron plate 2 is less than 50 microns, the attraction strength of the magnet will decrease,
This is not desirable as the product value decreases. Also, iron plate 2
If the thickness is 150 microns or more, the surface layer tends to crack when bent at right angles, which is undesirable.

FIG. 2 shows an example of the whiteboard 1 of the present invention, which is bent at right angles using the V-cut method. In this bending process, the core material 7 is attached to the back surface of the iron plate 2, the core material 7 is cut into a right triangle shape as shown in FIG. By bending the whiteboard 1 so as to make contact with the whiteboard 1, a whiteboard 1 bent at a right angle can be obtained as shown in FIG.

FIG. 4 shows an example of the whiteboard 1 of the present invention which has been bent into an arc shape using the R cut method. In this bending process, the core material 7 on the back side of the iron plate 2 is cut into an arc shape as shown in FIG. By bending the whiteboard 1 along the lines 10 and gluing it together, the whiteboard 1 bent into an arc shape as shown in FIG. 4 can be obtained.

As explained above, the whiteboard according to the present invention is produced by bonding parchment paper, tracing paper, glassine paper, liner paper, or latex-impregnated paper that contains almost no air bubbles to an iron plate, and applying a primer to the unsaturated polyester paper on the iron plate. Since the unsaturated polyester resin layer is formed using a wet film method, there is no heat and pressure during the formation of the unsaturated polyester resin layer, and no air bubbles rise from the paper layer underneath, making it easier to use than conventional methods. Therefore, remaining bubbles and pinholes in the unsaturated polyester resin layer 6 can be suppressed as much as possible. As a result, the whiteboard of the present invention can significantly improve the problem of marker ink residue, which is the most important performance for a whiteboard. In addition, since the paper and the unsaturated polyester resin layer are bonded via a primer that has an isocyanate group, the isocyanate group (NCO-) and the OH group of the unsaturated polyester resin layer are bonded together and are extremely strong. Adhesive strength can be obtained. Furthermore, the paper layer below the resin layer uses parchment paper, tracing paper, glassine paper, liner paper, latex impregnated paper, etc., so these papers have strong interlayer strength and large elasticity. , can contribute to improving adhesive strength. Furthermore, in the present invention, a steel plate with a thickness of about 50 to 150 microns is used, and a paper layer and an unsaturated polyester resin layer are formed on the surface to form a whiteboard. It provides bending workability that cannot be obtained with conventional enamel-type whiteboards, and it is possible to obtain whiteboards with shapes that are impossible with conventional whiteboards. In addition, in the present invention, since the unsaturated polyester resin layer is formed by a wet film method, in addition to the above-mentioned effect of improving the residual shadow of the marker ink, the unsaturated polyester resin layer is formed in a size that corresponds to diversifying market needs. It is also suitable for high-mix, low-volume production of different colors.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of the whiteboard according to the present invention, FIG. 2 is a cross-sectional view showing an example of the whiteboard of the present invention bent at right angles using the V-cut processing method, and FIG. FIG. 4 is a cross-sectional view showing an example of the whiteboard of the present invention bent into an arc shape by the R-cut process, and FIG. 5 is an explanatory view showing the manufacturing process. 1...Whiteboard, 2...Zinc thin iron plate, 3...Polyethylene film adhesive, 4...Paper, 5...Primer, 6...Unsaturated polyester resin layer, 7...
Core material, 8, 9...Cut surface, 10... Shape material.

Claims (1)

[Scope of Claims] 1. A thin iron plate of about 50 to 150 microns, paper such as parchment paper, tracing paper, glassine paper, liner paper, or latex-impregnated paper adhered to the surface, and an isocyanate group on the surface. What is claimed is: 1. A whiteboard comprising: an unsaturated polyester resin layer bonded via a primer having 2. Paper such as parchment paper, tracing paper, glassine paper, liner paper, or latex-impregnated paper is adhered to the surface of a thin iron plate of approximately 50 to 150 microns, and unsaturated polyester is applied on top of the paper using a primer having an isocyanate group. A method for manufacturing a whiteboard, characterized in that a resin layer is formed by a wet film method.