KR101205227B1 - Chalkboard having embossed friction layer - Google Patents

Abstract

An object of the present invention is a steel plate formed with a plating layer; And an emboss friction layer formed on the plating layer of the base steel sheet to form a blackboard plate surface, wherein the emboss friction layer comprises: a high polymer polyester resin; Crosslinked resins composed of an isocyanate resin and a melamine resin; Additives including a curing catalyst, a solvent, a leveling agent, an antifoaming agent and a pigment; And it is achieved by the blackboard embossed friction layer is characterized in that the coating composition comprising a non-uniform filler particles having a particle size of 5 ~ 50㎛ coated on the plated layer and then hardened and dried. According to the present invention, an embossed friction layer is provided which forms an embossed friction layer on the plated surface of the coated blackboard by mixing non-uniform pillar particles in the paint for forming the board surface, thereby improving usability and eraseability. .

Description

Chalkboard having embossed friction layer

The present invention relates to a blackboard formed with an embossed friction layer, and more specifically, by using an uneven filler particle mixed with a paint for forming a board of the board, an embossed friction layer is formed on the board of the coated board to improve usability and eraseability. It relates to a blackboard formed with an embossed friction layer.

1 is a photograph of a conventional board plate surface. Conventional blackboard plate surface is mainly formed by coating a white or blue paint on the steel plate is used to write or draw using black or white chalk on the blackboard plate.

Referring to Figure 1, it can be seen that the conventional blackboard plate surface is formed to have a fairly smooth surface. As a result of the low friction between the chalk and the board, if you press the chalk with a weak force, the letters or pictures written or drawn on the board will not be clear, and the chalk powder will not be separated from the board even if you erase the written contents. There are disadvantages in its use and erase, such as the need to erase the board several times.

Therefore, it is required to provide a sufficient degree of friction on the board surface, so that its use and eraseability can be improved, while maintaining a certain range of glossiness, so that it can fully function as a board.

The present invention is to provide a blackboard with an embossed friction layer formed by mixing the non-uniform pillar particles in the paint for forming the board surface to improve the usability and eraseability by forming an embossed friction layer on the surface of the painted board. .

An object of the present invention is a steel plate formed with a plating layer; And an emboss friction layer formed on the plating layer of the base steel sheet to form a blackboard plate surface, wherein the emboss friction layer comprises: a high polymer polyester resin; Crosslinked resins composed of an isocyanate resin and a melamine resin; Additives including a curing catalyst, a solvent, a leveling agent, an antifoaming agent and a pigment; And it is achieved by the blackboard embossed friction layer is characterized in that the coating composition comprising a non-uniform filler particles having a particle size of 5 ~ 50㎛ coated on the plated layer and then hardened and dried.

Here, the embossing formed in the embossed friction layer may be formed by the heterogeneous filler particles, and the heterogeneous filler particles may be acrylic beads.

The embossed friction layer has a glossiness of 10 to 20 degrees.

An antirust primer coating layer and / or a pretreatment layer may be further included under the embossed friction layer.

The coating composition for forming a board surface of the board is a high polymer polyester resin 25 to 55% by weight, a crosslinking agent 5 to 15% by weight, a curing catalyst 0.1 to 1.5% by weight, a solvent 30 to 45% by weight, filler particles 0.3 to 1.0% by weight, 0.5 to 1.0 wt% leveling agent, 0.5 to 1.0 wt% defoaming agent and 10 to 25 wt% pigment.

According to the present invention, the embossed friction layer is provided to form an embossed friction layer on the board surface of the painted board by mixing the selected non-uniform pillar particles in the paint for forming the board surface, thereby improving the usability and eraseability. By forming an embossed friction layer of appropriate gloss, it prevents diffuse reflection caused by plasticizers and other oils contained in the board maca, even when the board is used as a white board, which helps students to protect their eyesight and improve their concentration. It can also be used as a screen, eliminating the hassle of installing a separate screen separately. Moreover, the improved use and eraseability of the embossed friction layer allows the use of chalk and maca at the same time, giving users more options for writing tools.

1 is a photograph of a conventional board plate surface.
Figure 2 is a schematic cross-sectional view showing an enlarged configuration of the board surface according to the present invention.
3 is a photograph of the board surface formed in accordance with the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view schematically showing an enlarged configuration of a board according to the present invention, the board according to the present invention is a zinc or zinc alloy plated layer (2) is formed on the steel sheet (1), chromium thereon The acid or non-chromate pretreatment layer 3, the rust-preventive primer coating layer 4, and the embossed friction layer 5 are sequentially laminated.

The zinc or zinc alloy plating layer 2 is formed on the base steel sheet 1 by hot dip galvanizing-aluminum-silica alloy or electroplating and hot dip galvanizing.

The chromate or non-chromate pretreatment layer (3) is a phosphate coating, chromate, or non-phosphorus coating for securing interlayer adhesion between the base steel sheet 1 having the plating layer 2 and other coating layers and basic corrosion resistance. It is formed by a known chemical film treatment such as chromate or the like, but in some cases, the pretreatment layer 3 may not be formed.

The anti-corrosive primer coating layer 4 may be an epoxy or epoxy-modified polyester base coat, a PCM polyester base coat, or a modified base coat as an element that affects interlayer adhesion, coating hardness, chemical resistance, and corrosion resistance. Depending on the use and application of the interior and exterior materials for home appliances and construction, the commercially available undercoat for commercially available PCM may be appropriately selected, or primer coating may be omitted if necessary. Anti-rust pigments include Red Leed, Zinc Potassium Chromate, Zinc Tetraoxy Chromate, and Strontium Chromate containing lead and chromium. Barium Metaborate, Zinc Molybdate, Calcium Zinc Molybdate, Zinc Phosphate, Aluminum Triphosphate, Calcium Borosilicate, Phosphosilicate, Calcium Ionexchanged Silicate, Magnesium Ion-exchanged Silicate, and the like.

The embossed friction layer 5 according to the present invention is a blackboard plate surface in which an additive including a high polymer polyester resin, a crosslinking agent, a curing catalyst, a solvent and an antifoaming agent, a leveling agent and a pigment, and a non-uniform filler particle having a particle size of 5 to 50 µm are mixed. The coating material for forming is applied onto the base steel sheet 1 having the coating layers 2, 3, and 4 described above, followed by curing and drying.

The high-polymer polyester resin is contained in 25-55 weight% of said paints for board | substrate board surface formations based on the coating composition total weight. 5-15 wt% crosslinking agent, 0.1-1.5 wt% curing catalyst, 30-45 wt% solvent, 0.3-1.0 wt% filler particle, 0.5-1.0 wt% leveling agent, 0.5-1.0 wt% defoaming agent and pigment 10-25 It may contain weight percent.

Hereinafter, the coating composition for forming the embossed friction layer 5 according to the present invention will be described in more detail.

<High Polymer Polyester Resin>

As for the high polymer polyester resin used for this invention, it is preferable to use the number average molecular weights 10,000-13,000, the hydroxyl value 20-60 mgKOH / g, the acid value 1-5 mgKOH / g, and the glass transition temperature 20-40 degreeC.

At this time, if the number average molecular weight exceeds 13,000, the number of functional groups is too small, the crosslinking reactivity is lowered, and if the number average molecular weight is less than 10,000, the durability of the coating film cannot be maintained.

In the present invention, it is preferable to use the high-polymer polyester resin to include 25 to 55% by weight of the total coating composition, if the content is less than 25% by weight greatly reduces the flexibility and processability of the coating film, exceeds 55% by weight If it is, the fouling resistance and hardness of a coating film fall rapidly.

<Bridge school>

In the present invention, an isocyanate resin and a melamine resin are mixed and used as a crosslinking agent for forming the resin component and the coating film. The melamine resin includes a melamine resin containing an amino group or a butoxy group and a melamine resin containing a methoxy group.

In addition, in the present invention, it is preferable to use 5 to 15% by weight of the crosslinking agent with respect to the entire coating composition. If the content of the crosslinking agent is less than 5% by weight, the solvent resistance and hardness of the coating film are drastically reduced, and the content is more than 15% by weight. The softness and impact resistance of the coating film are lowered.

<Curing Catalyst>

It is used to increase the density of coating film by promoting crosslinking between high polymer polyester resin and crosslinking resin, and as curing catalyst, p-toluene sulfonic acid (p-TSA) or dinonylnaphthalene sulfonic acid (DNNSA), dinaphthalene disulfonic acid (DNNDSA), a neutralized sulfonic acid selected from fluoro sulfonic acid with amine or epoxy may be used. Tin catalyst (DBTDL) is also used for urethane crosslinking.

The curing catalyst is contained in the range of 0.1 to 1.5% by weight based on the total coating composition. If the content is less than 0.1%, curing of the coating film is insufficient depending on the working conditions, and if it exceeds 1.5%, curing of the coating film occurs too rapidly. When painting, popping occurs in the coating, deterioration of workability, and coating shrinkage.

<Solvent>

In the present invention, an appropriate amount of an organic solvent is used in consideration of characteristics in handling and painting work. As an organic solvent, it is preferable to mix and use a glycol ester type, a glycol ether type, which is a true solvent, and an aromatic hydrocarbon type which is an auxiliary solvent, etc. suitably.

The aromatic hydrocarbon solvents are Cocosol # 100, Cocosol # 150, Cocosol # 200 of Yugong Co., and glycol ester solvents are ethyl acetate, n-butyl acetate, cellosolve acetate, and propylene glycol of Union Carbide. Monomethyl acetate, 3-methoxy butyl acetate and the like. Examples of the glycol ether solvents include methyl cellosolve, ethyl cellosolve, ethylene glycol butyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, and diethylene glycol butyl ether from Union Carbide. Rice and the like, and examples of the alcohol solvent include ethanol, isopropanol, n-butanol, amyl alcohol, cyclohexanol and the like.

At this time, the amount of the solvent is added to the usual level, including the aromatic hydrocarbon solvent content contained in the high polymer polyester resin, it is preferable to contain in the range of 25 to 45% by weight based on the total coating composition. Outside this range, the flowability of the paint may be lowered, which may cause a problem of poor workability.

<Leveling agent, antifoaming agent, pigment>

In the present invention, it is preferable to use 0.5 to 1.0% by weight of an acrylic, vinyl or silicone leveling agent and an antifoaming agent, respectively, in order to maintain the coating film smoothness and to improve the antifoaming property during painting. As the leveling agent and the antifoaming agent, Disulon L-1980, Disparon L-1984, Disparon AP-30, BYK356 by BYK356, BYK410, etc. may be used.

The pigment is used to form the color of the board of the blackboard, mainly white or blue pigment is used, the addition amount is conventional level, it is sufficient to contain in the range of 10 to 25% by weight based on the total coating composition. Overuse reduces the quality of the paint, and adding too small a dose does not provide the expected effect.

<Filler particle>

The amount of the filler particles used in the present invention is preferably 0.3 to 1.0% based on the total weight of the paint, and the particle size is used by mixing the one corresponding to the range of 5 to 50㎛. In the present invention, the filler particles play the most important role in the formation of the embossed friction layer 5, and the irregular filler particles having a wide range of particle sizes are hardened and dried to form irregular and uneven embosses of the embossed friction layer 5. By increasing the usability and eraseability of the board. The particle size of the filler particles is a range selected so that the board surface according to the present invention can increase the usability and eraseability while maintaining a certain range, that is, the glossiness of 10 to 20 degrees, the particle size of the filler particles 5㎛ or less or 50㎛ or more It is difficult to increase the usability and eraseability of the board. In other words, when the particle size of the filler particles is less than 5㎛, the use force and eraseability are extremely reduced due to the low frictional force with the board surface, and when the particle size is 50㎛ or more, the consumption of chalk increases, but it is impossible to use clearly by large embossing. Erasability is also worse. In the present invention, the filler particles are acrylic beads.

The embossed friction layer-forming paint blended as described above is applied onto the base steel sheet 1 having the above-described coating layers 2, 3, and 4, and then cured and dried to form an embossed friction layer as shown in FIG. 2. 5, irregular and non-uniform embosses 5a are formed. Therefore, irregular and non-uniform embosses are formed on the board, thereby increasing the frictional force with the chalk than the conventional board, the use and eraseability of the board can be increased.

(Example)

20 parts by weight of isocyanate resin, 0.4 parts by weight of melamine resin, 0.4 parts by weight of p-toluene sulfonic acid (p-TSA) as a curing catalyst, 120 parts by weight of ethyl acetate as a solvent, and nonuniformity with respect to 100 parts by weight of high polymer polyester resin. 1.2 parts by weight of acrylic beads having a particle size of 5 to 50 μm as filler particles, 2.0 parts by weight of Disparon L-1980 as a leveling agent, 2.0 parts by weight of Disparon L-1984 as an antifoaming agent and 40 parts by weight of a blue pigment, and an embossed friction layer. Mixing paints for forming, roll-coated on the base steel sheet (1) formed with zinc or zinc alloy plated layer (2), pretreatment layer (3), rust preventive primer plating layer (4) and heat-cured at 120 ℃ ~ 280 ℃ To form a board surface.

A photograph of the board surface formed as described above is illustrated in FIG. 3. Referring to FIG. 3, the smoothness is less than that of the conventional board, and it can be confirmed that irregularities and irregularities of emboss are formed on the board. As a result of measuring the glossiness of the board | substrate board formed in this way using the glossimeter, the glossiness was 15 degrees.

By forming the board surface of the embossed friction layer, not only can the use and eraseability be greatly improved than the conventional board surface, but also when used as a screen with a writing function such as a white board, it is possible to suppress the diffuse reflection and make clear projection. Done. In addition, the improved usability and eraseability of the embossed friction layer allows the use of chalk and maca at the same time, giving users more options for writing tools.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, such modifications or variations will have to be belong to the claims of the present invention.

1: base steel sheet 2: zinc or zinc alloy plated layer
3: pretreatment layer 4: antirust primer coating layer
5: emboss friction layer

Claims (5)

A steel sheet having a plating layer formed thereon; And
An embossed friction layer formed on the plating layer of the base steel sheet to form a blackboard plate surface;
The embossed friction layer,
High polymer polyester resins; Crosslinked resins composed of an isocyanate resin and a melamine resin; Additives including a curing catalyst, a solvent, a leveling agent, an antifoaming agent and a pigment; And a coating composition for forming a board surface of the blackboard including non-uniform filler particles having a particle size of 5 to 50 μm, applied on the plating layer, and then cured and dried.
The embossed friction layer is a blackboard embossed friction layer is characterized in that the gloss 10 ~ 20 degrees. The method of claim 1,
The embossing layer formed on the embossed friction layer is formed by the non-uniform filler particles, wherein the non-uniform filler particles are acrylic beads, characterized in that the blackboard with embossed friction layer. delete The method of claim 1,
The board having an embossed friction layer, further comprising an antirust primer coating layer, a pretreatment layer, or an rustproof primer coating layer and a pretreatment layer under the embossed friction layer. The method of claim 1,
The paint composition for forming the board surface,
High polymer polyester resin 25-55 weight%, crosslinking agent 5-15 weight%, curing catalyst 0.1-1.5 weight%, solvent 30-45 weight%, filler particle 0.3-1.0 weight%, leveling agent 0.5-1.0 weight%, antifoamer A blackboard with an embossed friction layer, characterized by containing 0.5 to 1.0% by weight and pigments 10 to 25% by weight.

Images