KR100568347B1 - Coating composition for shiringkage band steel having improved burning and welding resistability and the shiringkage band steel thereof - Google Patents

Abstract

The present invention relates to a steel sheet coating resin composition for CRT bands, a method for manufacturing a CRT band steel plate using the same, and a CRT band steel sheet excellent in flame resistance and weldability prepared therefrom.

Provided is a resin composition for coating a steel sheet for a CRT band, comprising 2-10 parts by weight of nanosilicate silicate, 100-140 parts by weight of silica and 10-30 parts by weight of metal powder of zinc and / or tin per 100 parts by weight of the silicone resin. ,

In addition, the resin composition is coated on a chromate-treated zinc-nickel alloy plated steel sheet, baked and dried at a temperature of 160-250 ° C. to provide a method for manufacturing a steel sheet for CRT band, characterized in that a resin film thickness of 0.5-3.0 μm is formed. do. In addition, there is provided a steel sheet for a CRT band produced by the above method.

According to the present invention, by mixing a metal powder in a water-soluble silicone resin having excellent heat resistance, a band steel sheet for CRT can be produced with improved corrosion resistance and weldability after high temperature heating of the band steel sheet.

Silicone resin, silicate, silica, zinc, tin, metal powder

Description

COATING COMPOSITION FOR SHIRINGKAGE BAND STEEL HAVING IMPROVED BURNING AND WELDING RESISTABILITY AND THE SHIRINGKAGE BAND STEEL THEREOF}

The present invention relates to a steel sheet coating resin composition for CRT bands, a method for manufacturing a CRT band steel plate using the same, and a CRT band steel sheet excellent in flame resistance and weldability prepared therefrom.

The Shrinkingage band steel sheet used in the CRT tube for TV and monitor is used as a safety device by fixing the upper part of the TV Braun tube in the form of band using aluminum plating steel plate by hot dip plating. . To explain this in more detail, a TV or monitor CRT consists of a 5-10 mm thick glass tube to maintain a high vacuum of about 10 ^-7 Torr. On the other hand, if the glass tube bursts due to severe impact from the outside, the glass may be scattered into pieces due to the internal vacuum, which may cause a large accident. Even if the glass tube bursts, the glass fragments are designed to sink into the interior.

Glass tube fastening method in a conventional CRT tube is a CRT tube in a state in which the frame of the steel plate is rapidly heated to 500 to 600 ° C. within a few seconds by an electric resistance heating method by an electric resistance heating method. By mounting and cooling by air cooling (air cooling) is a method that is fixed to the CRT as the steel sheet shrinks. However, in general, in case of cold rolled steel sheet, it is difficult to use because it is corroded well after being fastened to CRT. . On the other hand, the reason why it is difficult to apply pure galvanized steel sheet is that when heated to a high temperature and thermally expanded, it is heated to a temperature higher than the melting point of zinc, so in the case of pure zinc, zinc melts and flows down to the glass of the CRT. This may cause damage to the exterior of the CRT product.

On the other hand, zinc-plated steel sheet having excellent heat discoloration resistance, fuming resistance upon heating, corrosion resistance and scratch resistance after heating has a straight silicone resin coating on the surface of the zinc-based plating steel sheet of Japanese Patent Publication No. JP 2000-15741A. It is characterized in that formed in 0.1 ~ 3 g / m ² in terms of SiO ₂ . In this case, a resin solution composition in which silica is dispersed in a silicone resin is described as a method of improving heat resistance corrosion resistance of a band steel sheet, but in this case, only one type of silica is used as the silicone resin is a solvent type and an additive.

Looking at the required physical properties of the steel sheet used in the Shrinkeage band used for TV and monitor CRT, it is divided into the strength, weldability, flame resistance and corrosion resistance of the band steel sheet. Looking at this in more detail, a steel plate having an appropriate level of tensile strength and thickness is required according to the size of the CRT. The larger the inch of the CRT (the length of the diagonal of the CRT is generally called the size of the CRT), the larger the band steel sheet is. The thickness should be thick to match the degree of vacuum and conversely, the smaller the CRT inches, the thinner the steel sheet would be. The steel sheet is cut into bands to form a proper size, and both sides are welded to form a square shape by resistance welding. At this time, when welding the steel sheet, if the thickness of the resin layer at the time of welding not only the welding is not good, but also spatter (spatter) during the welding, the surface quality of the band steel sheet worsens.

Then, when the steel sheet is heated to 500 ~ 600 ℃ PMT (Peak Metal Temperature) to cover the band steel plate on the CRT, the organic material on the surface is pyrolyzed to generate smoke. As a result, the environment of the CRT workplace is deteriorated. Therefore, when the steel sheet is heated by the electric resistance method, there should be no smoke. The thermally expanded band steel sheet is sandwiched in the glass tube and then some time passes until the final assembly process takes place. At this time, the band steel sheet should be secured to corrosion resistance even in various surrounding environments (or high temperature and high humidity atmosphere).

Among the required qualities of the above-described CRT band steel sheet, the present invention provides a resin composition applied to the upper part to make a band steel sheet excellent in flame resistance (characteristics in which smoke does not occur) and weldability.

Accordingly, the present invention provides a resin composition for coating a steel sheet for a CRT band, in which weld resistance is greatly improved by including water-soluble silicone resin and colloidal silica in consideration of environmental friendliness, and significantly improving weldability by including a metal powder in a resin solution. .

Another object of the present invention is to provide a method for producing a steel sheet for a shingkeji band used in the CRT using the resin composition.

Still another object of the present invention is to provide a steel sheet for a CRT band manufactured by the above method.

According to one aspect of the invention,

Provided is a resin composition for coating a steel sheet for a CRT band, comprising 2-10 parts by weight of nanosilicate silicate, 100-140 parts by weight of silica and 10-30 parts by weight of metal powder of zinc and / or tin per 100 parts by weight of the silicone resin. do.

According to another aspect of the present invention,

On the chromated zinc-nickel alloy plated steel sheet

A resin composition comprising 2-10 parts by weight of nanosilicate silicate, 100-140 parts by weight of silica and 10-30 parts by weight of metal powder of zinc and / or tin is applied per 100 parts by weight of the silicone resin and baked at a temperature of 160-250 ° C. Provided is a method for producing a steel plate for a CRT band, characterized by drying to form a resin coating film thickness of 0.5-3.0 μm.

According to still another aspect of the present invention, there is provided a steel sheet for a CRT band manufactured by the above method.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The resin composition for coating a steel sheet for a CRT band of the present invention includes a water-soluble silicone resin as a main resin and nano-dispersed silicate therein, followed by silica and tin (Sn) and / or zinc (Zn) powder. It is done by input.

The silicone resin has a siloxane bond in terms of the resin molecular structure and is composed of a compound that is stable at high temperature, and thus has excellent thermal decomposition ability. Preferably, it is preferable to contain at least one or more phenyl groups and methyl groups. In particular, the higher the phenyl group content than the methyl group portion, the better the flame resistance and the more preferable.

The silicate is added to the silicone resin by nano dispersion, and the input content is 2 to 10 parts by weight based on the silicone resin content. If the added content is 2 parts by weight or less, the content of the resin layer is too small to reduce the corrosion resistance effect. On the contrary, if the content is more than 10 parts by weight, the viscosity of the solution is too high because nanoparticles of silicate are present in the form of layers. It is not preferable because the coating generates streaks and the like.

For example, the silicates can be nanonized using a silicate called Montmorillonite {molecular formula: M ^{n +} .yH ₂ O [Al _4x Mg _x ] (si ₈ ) O ₂₀ (OH ₄ )}. The montmorillonite can be dispersed in aqueous solution using an organic agent called alkylammonium, which is swelled with pure water but is hydrophobic. That is, the spacing between the layers is increased so that the silicates may be split into thin thin plates and dispersed in the aqueous solution. As described above, since the nanosilicate has a plate-like structure, it can be said that it is more effective in blocking external corrosion factors than silica having spherical or needle shape. In the case of general silica, it is added to obtain a filling effect, and when the pH is not well in solution, the corrosion blocking effect is lowered because it aggregates itself to form secondary particles. When present, silica fills the micro-spaces between layers, resulting in a perfect and dense coating structure, which provides excellent corrosion protection.

In addition, the content of silica included in the resin composition of the present invention is 100 to 140 parts by weight relative to the resin content, when the silica content is 100 parts by weight or less, the main resin content is increased, the flame resistance is lowered, and on the contrary, the silica content is 140 weight parts. If it is more than a portion, it is not preferable because the content of silica in the resin film is so large that the resin layer film is firm and the resin adhesiveness is lowered.

In addition, the type of metal powder included in the resin composition of the present invention is suitable for zinc (Zn) and tin (Sn) having a melting point of 600 ° C. or lower, and mixing one or two kinds thereof. You may use it. The content is 10 to 30 parts by weight relative to the silicone resin content. When the metal powder content is 10 parts by weight or less, there is no effect of improving weldability, and when the metal powder content is 30 parts by weight or more, the effect is insignificant compared to the metal powder input content, which is not economical.

Furthermore, the steel sheet for CRT band can be manufactured by apply | coating the resin composition of this invention to the chromate-treated zinc-nickel alloy plated steel sheet, baking it at high temperature, and drying to form a resin coating film. The baking temperature is preferably 160-250 ° C., and if baking is performed at 160 ° C. or less, baking of the resin film may not be sufficient, making it difficult to secure adhesion between the resin layer and the underlying layer, and reducing chemical stability. In addition, when the baking is performed at a temperature of 250 ° C. or higher, the effect on the quality of the resin coating film is not great and is rather economically damaging.

And the thickness of the resin film is 0.5 ~ 3.0㎛, if the thickness of the resin coating film is 0.5㎛ or less, it is difficult to secure the corrosion resistance, on the contrary, if it is 3.0㎛ or more, the content of the resin in the resin composition is too much, the flame resistance and weldability may be lowered. .

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example

Using a chromate-treated material on a Zn-Ni electroplated steel sheet having a plating adhesion of 20 g / m2, roll coating was carried out while varying the type and content of each additive in the water-soluble silicone resin as shown in Table 1-5. Then, the baking temperature (baking) was treated to 200 ℃, and then immediately cooled (water cooling) to produce a shingkeji band steel sheet with a dry thickness of 1.0㎛ the resin layer.

Flame resistance evaluation is to expand the band steel sheet to about 600 ℃ by using a resistance heating method to hold both sides of the 50 × 150mm band steel sheet with a metal grip (grip) through a constant current. At this time, the presence of smoke generated on the surface of the band steel sheet during resistance heating and the state of the surface after heating were visually evaluated as follows.

 ◎: No smoke or surface discoloration when heating resistance

: No smoke generated during resistance heating but surface appearance change

   (Triangle | delta): The smoke generate | occur | produces little, but the appearance does not change in resistance heating.

       X: Smoke occurs during resistance heating

The weldability evaluation of the band steel sheet was evaluated by spot welding. The spot welding machine used was an air compression welding machine (DAIHEN PRA-33A). The pressing force was 250kgf and the welding time was 15 cycles. Spot weldability was evaluated for the degree of spatter generation during spot welding and the number of RBIs exceeding the class B strength standard of the Japanese Industrial Standard (JIS Z 3140).

      ◎: Less spatter during spot welding, RBI 500 or more

: 스폿 용접시 스패터 발생이 적으며, 타점수 100~500

: Less spatter when spot welding, 100-500 RBI

        X: Spatter occurs in spot welding, RBI score is 100 or less

For corrosion resistance evaluation, white rust and red blue (red rust) generated on 50x150mm specimens after 8 cycles of salt spray test and 16 cycles after stopping the salt spray and leaving it in the salt sprayer for 7 cycles were tested. rust) degree of comparison was evaluated.

        ◎: No white rust

: 백청발생율이 10% 이하

: Less than 10% of white rust

△: white blue occurrence rate is 10-30%, red blue occurs

    X: more than 50% of white rust or 10% of red rust

The evaluation results are shown in Table 1-5 below.

 division  Resin (parts by weight) additive Quality evaluation Silicate Silica Metal powder  Flame resistance  Weldability  Corrosion resistance shape Content (parts by weight) Particle size Content (parts by weight) Kinds Content (parts by weight) Comparative Example 1 100 parts by weight of water-soluble silicone resin   Nano dispersion One   20 nm   120   Sn   15 ◎ △ △ Inventive Example 1 2 ◎ ◎ ◎ Inventive Example 2 5 ◎ ◎ ◎ Inventive Example 3 10 ◎ ◎ ◎ Comparative Example 2 15 △ ◎ ◎

 division  Resin (parts by weight) additive Quality evaluation Silicate Silica Metal powder  Flame resistance  Weldability  Corrosion resistance shape Content (parts by weight) Particle size Content (parts by weight) Kinds Content (parts by weight) Comparative Example 3 100 parts by weight of water-soluble silicone resin   Nano dispersion   5   20 nm 90   Sn   15 △ ◎

Inventive Example 4 100 ◎ ◎ ◎ Inventive Example 5 120 ◎ ◎ ◎ Inventive Example 6 140 ◎ ◎ ◎ Comparative Example 4 150

◎ △

division Resin (parts by weight) additive Quality evaluation Silicate Silica Metal powder Flame resistance Weldability Corrosion resistance shape Content (parts by weight) Particle size Content (parts by weight) Kinds Content (parts by weight) Comparative Example 5   100 parts by weight of water-soluble silicone resin    Nano dispersion    5    20 nm    120 Sn 5 ◎ △ ◎ Inventive Example 7 10 ◎ ◎ ◎ Inventive Example 8 20 ◎ ◎ ◎ Inventive Example 9 30 ◎ ◎ ◎ Comparative Example 6 40

◎ △ Comparative Example 7 Zn 5 ◎ △ ◎ Inventive Example 10 10 ◎ ◎ ◎ Inventive Example 11 20 ◎ ◎ ◎ Inventive Example 12 30 ◎ ◎ ◎ Comparative Example 8 40

◎ △

division Resin Type (parts by weight) additive Quality evaluation Silicate Silica Metal powder Flame resistance Weldability Corrosion resistance shape Content (parts by weight) Particle size Content (parts by weight) Kinds Content (parts by weight) Comparative Example 9 Epoxy  Nano dispersion  5  20 nm  120  Sn  15 X ◎ ◎ Comparative Example 10 Phenoxy X ◎ ◎ Comparative Example 11 Teflon △ ◎ ◎ Inventive Example 13 silicon ◎ ◎ ◎

division Resin Thickness (㎛) additive Quality evaluation Silicate  Silica Metal powder Flame resistance Weldability Corrosion resistance shape Content (parts by weight) Particle size Content (parts by weight) Kinds Content (parts by weight) Comparative Example 12 0.5  Nano dispersion  5  20 nm  120  Sn  15 ◎ ◎ △ Inventive Example 14 0.7 ◎ ◎ ◎ Inventive Example 15 1.5 ◎ ◎ ◎ Inventive Example 16 3.0 ◎ ◎ ◎ Comparative Example 13 3.5 △ △ ◎

As shown in Table 1-5, it can be seen that the band steel sheet of Inventive Example 1-16 manufactured according to the method of the present invention exhibits excellent flame resistance, weldability and corrosion resistance as compared to Comparative Examples 1-13.

According to the present invention, by mixing a metal powder with a water-soluble silicone resin having excellent heat resistance, it is possible to produce a band steel sheet for CRT tube having improved corrosion resistance and weldability after high temperature heating of the band steel sheet.

Claims (3)

2-10 parts by weight of nanosilicate silicate, 100-140 parts by weight of silica and 10-30 parts by weight of metal powder of zinc and / or tin, per 100 parts by weight of silicone resin. On the chromated zinc-nickel alloy plated steel sheet A resin composition comprising 2-10 parts by weight of nanosilicate silicate, 100-140 parts by weight of silica and 10-30 parts by weight of metal powder of zinc and / or tin is applied per 100 parts by weight of the silicone resin and baked at a temperature of 160-250 ° C. A steel sheet manufacturing method for a CRT band, characterized by drying to form a resin coating film thickness of 0.5-3.0 μm. Steel plate for CRT band produced by the method of claim 2.