KR20200037892A - Water soluble surface treatment composition for lubrication and stainless steel sheet coated with the composition - Google Patents

Abstract

The present invention relates to a water-soluble surface treatment composition for lubrication and a lubricating stainless steel sheet coated with the same. An object of the present invention is to provide the composition and the sheet, of which a coated surface treatment agent may be easily dissolved by an alkali degreasing agent, if the coated surface treatment agent is to be peeled off, without a need for using a separate lubricating oil and without a need for a process of removing the lubricating oil. To that end, the present invention provides the water-soluble surface treatment composition for lubrication, which is applied onto one surface or both surfaces of the stainless steel sheet, the composition comprising: 20-60 wt% of water-soluble olefin resin; 5-10 wt% of inorganic metal sol; 1-10 wt% of lubricating wax; and 0.5-2 wt% of a metal chelating agent based on the total composition, in which a remainder contains a solvent.

Description

WATER SOLUBLE SURFACE TREATMENT COMPOSITION FOR LUBRICATION AND STAINLESS STEEL SHEET COATED WITH THE COMPOSITION}

The present invention relates to a water-soluble lubricating surface treatment coating composition and a stainless steel lubricating steel sheet coated with the composition, and more specifically, by applying a non-chromium type water-soluble lubricating surface treatment coating composition to one or both surfaces of a stainless steel sheet, When processing, there is no need to use a separate lubricating oil, a process of removing the lubricating oil after processing is unnecessary, and when it is necessary to peel off the coating layer of the lubricating surface treatment agent, the water-soluble lubricating surface treatment coating composition and it can be easily dissolved. The present invention relates to a stainless steel lubricated steel sheet coated with a composition.

In many cases, stainless steel sheet is processed and used in a complicated form, not in a sheet state.

In order to process the stainless steel sheet, it is processed using an oil-based processing oil such as lubricant, and after processing, is subjected to a degreasing process to remove the lubricant, and then formed into a final product.

However, the conventional method as described above, there is a disadvantage in that the work is cumbersome because a lubricant is used in the processing of the steel sheet, and an additional process for removing the lubricant after processing the steel sheet is required.

As a result, problems have been pointed out that the number of work hours increases and productivity decreases.

The present invention is to solve the above-mentioned problems of the prior art, the purpose of not using a separate lubricant when processing a stainless steel sheet.

Another object of the present invention is to avoid the need to supply a separate lubricant when processing a stainless steel sheet, and to eliminate the need for a process of removing the lubricant after processing is complete.

Another object of the present invention is to enable the surface treatment agent coating layer to be easily dissolved when it is intended to be used by peeling (de-filming) the lubricating surface treatment agent.

Another object of the present invention is to provide a water-soluble lubricating surface treatment coating composition having excellent workability, excellent fingerprint resistance, scratch resistance, and coating film release property.

In order to achieve the above object, the present invention is a water-soluble lubricating surface treatment coating composition applied to one or both surfaces of a stainless steel sheet, wherein the lubricating surface treatment coating composition has a water-soluble olefin resin of 20 to 60 based on the total composition. It is characterized in that it contains 5% to 10% by weight of an inorganic metal sol, 1 to 10% by weight of a lubricating wax, and 0.5 to 2% by weight of a metal chelating agent, and the balance comprises a solvent.

In addition, the water-soluble olefin resin is characterized in that the weight average molecular weight is 7,000 ~ 15,000, the acid value is 50 ~ 170mgKOH / g.

In addition, the inorganic metal sol is characterized in that it comprises one or two or more selected from the group consisting of silica sol, alumina sol, titania sol, and zirconia sol.

In addition, the average particle size of the inorganic metal sol is characterized in that 5 ~ 30nm.

In addition, the lubricating wax is selected from the group consisting of paraffin wax, olefin wax, carnauba wax, polyester wax, polyethylen wax, polypropylene wax, polyethylene-teflon wax, and poly teflon wax. It is characterized by including a species or two or more.

In addition, the metal chelating agent is characterized in that it comprises one or two or more selected from the group consisting of silane-based, titanium-based, and zirconium-based.

In addition, the silane-based chelating agent, vinyl triethoxy silane, 3-glycyloxyproc trimethoxysilane, 3-glycyloxypropyl triethoxysilane, 3-glycyloxypropylmethyl dimethoxy silane, N-2 It is characterized by including one or two or more selected from-(aminoethyl) -3-aminopropyl triethoxy silane, 3-aminopropyl trimethoxy silane, and 3-aminopropyl triethoxy silane.

In addition, the titanium-based chelating agent is characterized in that it comprises one or two or more selected from titanium acetylacetonate, iso-butoxytitanium ethyl acetoacetate, tetraisopropyl titanate, and tetranormal butyl titanate.

In addition, the zirconium-based coupling agent, tetra normal-propyl zirconate, tetra normal-butyl zirconate, sodium, potassium, lithium, ammonium salt of zirconium carbonate, triethanol amine zirconate, hexafluoro zirconate It is characterized by including one or two or more.

In addition, it characterized in that the water-soluble lubricating surface treatment coating composition is applied to one or both sides of the stainless steel sheet so that the dry film thickness is 1 to 5 μm.

According to the present invention, when processing a stainless steel sheet, there is no need to use a separate lubricant, and a degreasing step of removing the lubricant after processing is not required.

Accordingly, it is possible to reduce the cost by simplifying the work process and to improve productivity.

In addition, when it is necessary to peel (de-film) the lubricating surface treatment agent after processing the stainless steel sheet, there is an effect of easily dissolving the surface treatment agent coating layer with an alkali degreasing agent.

In addition, it is possible to secure the workability of the stainless steel sheet, and at the same time, there is an effect that can improve the anti-fingerprint, scratch resistance, and film-removability of the coating film.

1 is a schematic cross-sectional view of a stainless steel lubricating steel sheet manufactured according to the present invention.

Hereinafter, preferred embodiments of the water-soluble lubricating surface treatment coating composition according to the present invention will be described in detail.

The water-soluble lubricating surface treatment coating composition of the present invention is a non-chrome type containing no hexavalent chromium, based on the total composition, water-soluble olefin resin is 20 to 60% by weight, inorganic metal sol is 5 to 10% by weight, 1 to 10% by weight of a lubricating wax, 0.5 to 2% by weight of a metal chelating agent, and the remainder comprising a solvent.

Each component will be described below.

<Water-soluble olefin resin>

The water-soluble olefin resin is a main component of the water-soluble lubricating surface treatment paint according to the present invention, and functions to secure basic film-removability and processability, and is preferably contained in an amount of 20 to 60% by weight based on the total composition.

If the content of the water-soluble olefin resin is less than 20% by weight, it is difficult to form a coating film, and thus a solid coating layer cannot be formed, and the proportion of colloidal silica is relatively increased.

Accordingly, there is a problem in that the coating layer is brittle and the coating layer is broken when the steel sheet is processed.

And when the content of the water-soluble olefin resin exceeds 60% by weight, the content of the colloidal silica is relatively reduced, there is a problem that the scratch resistance (Scratch) of the coating film is lowered.

In addition, it is preferable that the water-soluble olefin resin has a weight average molecular weight of 7,000 to 15,000 and an acid value of 50 to 170 mgKOH / g.

When the acid value of the water-soluble olefin resin is less than 50 mgKOH / g, the water dispersion stability is lowered, and it is difficult to meet the required physical properties due to the small number of functional groups capable of reacting with the inorganic binder and the coupling agent.

In addition, when the acid value exceeds 170 mgKOH / g, the water dispersion stability is excellent, but there is a problem in that the coating film is peeled off by moisture due to the weak water resistance after drying the coating film.

<Inorganic metal sol>

The inorganic metal sol is intended to improve scratch resistance and hardness of the coating film, and preferably contains one or two or more selected from the group consisting of silica sol, alumina sol, titania sol, and zirconia sol.

In addition, the inorganic metal sol is preferably contained 5 to 10% by weight based on the total composition.

When the content of the inorganic metal sol exceeds 10% by weight, the coating film becomes brittle, and the powdering and coating film are broken during processing and the fingerprint resistance is deteriorated.

And when the inorganic metal sol is added to less than 5% by weight, it is difficult to secure the scratch resistance of the coating film.

<Lubrication Wax>

The lubricating wax acts to reduce the friction coefficient on the surface of the material to provide high lubricity, and prevents galling phenomenon in which the coating film is pushed at the processing site, thereby improving workability during press forming or ironing.

The lubricating wax is selected from the group consisting of paraffin wax, olefin wax, carnauba wax, polyester wax, polyethylen wax, polypropylene wax, polyethylene-teflon wax, and poly teflon wax. It is preferable to contain 1.0 to 10% by weight of the species or two or more.

When the content of the lubricating wax is less than 1.0% by weight, the slip property is insufficient, resulting in destruction of the surface treatment layer and the material during press working.

In addition, when the weight of the lubricating wax exceeds 10% by weight, excessive lubricant particles are distributed on the surface of the coating film, thereby reducing strength or separating the lubricating surface treatment agent.

<Metal chelating agent>

The metal chelating agent is composed of one or more mixtures selected from the group consisting of silane-based, titanium-based, and zirconium-based materials, and the content is preferably 0.5 to 2% by weight.

When the amount of the metal chelating agent is less than 0.5% by weight, the adhesion between the material and the coating film becomes weak, and the effect of strengthening the film by forming an internal net structure is weakened.

And when the content of the metal chelating agent exceeds 2% by weight, the chelating component remaining unreacted will weaken the adhesion of the coating film, and the cost will increase, which is uneconomical.

Examples of the silane-based chelating agent include vinyl triethoxy silane, 3-glycyloxyproc trimethoxysilane, 3-glycyloxypropyl triethoxysilane, 3-glycyloxypropylmethyl dimethoxy silane, and N-2- It is preferable to include one or two or more of (aminoethyl) -3-aminopropyl triethoxy silane, 3-aminopropyl trimethoxy silane, and 3-aminopropyl triethoxy silane.

As the titanium-based chelating agent, it is preferable to include one or two or more of titanium acetylacetonate, iso-butoxytitanium ethyl acetoacetate, tetraisopropyl titanate, and tetranormal butyl titanate.

The zirconium-based coupling agent, tetra normal-propyl zirconate, tetra normal-butyl zirconate, sodium, potassium, lithium, ammonium salt of zirconium carbonate, triethanol amine zirconate, hexafluoro zirconate 1 It is preferable to include a species or two or more species.

And the water-soluble lubricating surface treatment coating composition according to the present invention contains a solvent as the remainder in addition to the above-mentioned components.

 As the solvent, water, an organic solvent, or the like can be used, and water is preferably used. Water is used to dilute the resins. Deionized water or distilled water is preferred.

Hereinafter, experimental examples of the present invention will be described in detail.

First, 20 g of ethylene acrylic acid copolymer resin and 5.56 g of triethylamine were mixed with 75.5 g of distilled water, and the temperature was raised to 80 to 100 ° C. to prepare a copolymer resin.

A water-soluble lubricating surface treatment paint composition is prepared by mixing 20 to 60 wt% of a water-soluble olefin resin prepared as above, 5 to 10 wt% of an inorganic metal sol, 1 to 10 wt% of a lubricating wax, and 0.5 to 2 wt% of a metal chelating agent. Did.

Subsequently, test specimens for evaluating the reliability of the water-soluble lubricating surface treatment coating composition prepared as above were prepared as follows.

That is, the stainless steel sheet is cut into 7cm X 15cm in width to remove oil, and after coating the water-soluble lubricating surface treatment coating composition prepared as above with a coating amount of 2μm, bar is cured under the condition of PMT 110 ℃ to test specimen After fabrication, the following physical properties were evaluated.

<Processability>

Molding experiments were performed using a hydraulic mold tester with a cylindrical punch, and galling wear characteristics during molding were visually evaluated.

Two levels of temperature condition were used: room temperature and 100 ° C, the punch size was 45 mmø, the punch speed was 20 mm / min, the blank size was 100 mmø, the processing height was 25 mm, and the unfolding load was 3 tons.

And the evaluation of the galling wear properties during molding, ◎: no defects on the surface of the steel sheet, ○: no defects on the surface of the steel sheet, but the discoloration of the sliding surface is weak, △: galling wear is weakly generated on the surface of the steel sheet Ham, X: It was evaluated that a large number of linear galling wear occurs on the steel sheet surface.

<Fingerprint resistance>

The surface of the steel sheet treated with the trivalent chromium surface treatment composition was coated with petrolatum, and after standing for 10 minutes, petrolatum was removed, and then the color difference before / after application of petrolatum was observed.

Evaluation criteria at this time were evaluated as ΔE <2: excellent, 2 <ΔE <3: good, and ΔE> 3: poor.

<Desorption property>

The film-removing property shows the removal property of the lubricating surface-treated coating film, and the steel sheet coated with the water-soluble lubricating surface-treated coating composition is immersed in an alkaline degreasing solution for 2 minutes at 60 ° C, washed with water, and whether or not the film is peeled after air blowing. Confirmed.

The evaluation criteria at this time were ◎: no coating film residue, ○: 5% or more of the coating film residual ratio, Δ: 5 to 10% of the coating film residual ratio, and Ｘ: the coating film residual ratio exceeded 10%.

<Experiment 1> Change in physical properties according to the content of water-soluble olefin resin

In order to evaluate the change in physical properties according to the content of the water-soluble olefin resin, each water-soluble lubricating surface treatment coating composition was prepared by varying the content of the water-soluble olefin resin.

Subsequently, a test specimen was prepared using each water-soluble lubricating surface treatment paint composition, and then the above-described physical property evaluation was performed.

[Table 1] below shows the results, and for convenience of comparison, Comparative Examples 1, Inventive Examples 1 to 4, and Comparative Examples 2 were sequentially displayed.

Evaluation results of <Experimental Example 1> division Water-soluble olefin resin weapon
Metal sol Lubrication
Wax metal
Chelating agent Processability
Anti-fingerprint
Desorption Comparative Example 1 10 10 2 2 Ｘ Bad ◎ Inventive Example 1 20 10 2 2 ○ Good ◎ Inventive Example 2 30 10 2 2 ◎ Great ◎ Inventive Example 3 40 10 2 2 ◎ Great ◎ Inventive Example 4 60 10 2 2 ○ Great ○ Comparative Example 2 70 10 2 2 Δ Great Δ

As can be seen from [Table 1], Inventive Examples 1 to 4 in which 20 to 60% by weight of a water-soluble olefin resin was added according to the present invention showed good or better results in all physical properties. On the other hand, in Comparative Example 1 in which 10% by weight of water-soluble olefin resin was added, processability and fingerprint resistance were poor, and in Comparative Example 2 in which 70% by weight of water-soluble olefin resin was added, poor results were observed in all properties other than fingerprint resistance. .

Therefore, the content of the water-soluble olefin resin is preferably 20 to 60% by weight.

<Experimental Example 2> Changes in physical properties according to the acid value of the water-soluble olefin resin

To evaluate the change in physical properties according to the acid value of the water-soluble olefin resin, each water-soluble lubricating surface treatment paint composition was prepared by varying the acid value of the water-soluble olefin resin.

A coating composition was prepared according to Inventive Example 3, which showed excellent results in <Experimental Example 1>, and the change in physical properties according to the acid value of the water-soluble olefin resin added thereto was observed. [Table 2] below shows the results.

Changes in physical properties according to acid value of water-soluble olefin resin division receptivity
Olefin resin
Acid value (mgKOH / g) Processability Anti-fingerprint Desorption Comparative Example 3 40 Ｘ Bad Ｘ Inventive Example 5 50 ○ Good ○ Inventive Example 6 100 ◎ Great ◎ Inventive Example 7 170 ◎ Good ◎ Comparative Example 4 180 ○ Bad ◎

As can be seen from [Table 2], in the case of Comparative Example 3 in which the acid value of the water-soluble olefin resin was 40 mgKOH / g, there were few functional groups to react, resulting in poor descalability, fingerprint resistance, and processability. In the case of Comparative Example 4 in which the olefin resin had an acid value of 180 mgKOH / g, due to the de-filming phenomenon due to moisture as the hydrophilic functional groups were distributed too much, the coating film was de-filmed when evaluating fingerprint resistance.

On the other hand, in the case of Inventive Examples 5 to 7 using a water-soluble olefin resin having an acid value in the range of 50 to 170 mgKOH / g, the results showed good or better in all physical properties.

Therefore, it is preferable that the acid value of the water-soluble olefin resin is 50 to 170 mgKOH / g.

<Experimental Example 3> Change in physical properties according to the content of inorganic metal sol

 A coating composition was prepared according to Inventive Example 6, which showed excellent results in the evaluation of the physical properties of <Experimental Example 2>, and the change in physical properties according to the content of the inorganic metal sol added thereto was observed.

After preparing test specimens using each of the coating compositions prepared as above, physical properties were evaluated. [Table 3] below shows the results.

Changes in physical properties according to the content of inorganic metal sol division Inorganic metal sol Processability Anti-fingerprint Desorption Comparative Example 5 2 Ｘ Great ◎ Inventive Example 8 5 ○ Great ◎ Inventive Example 9 8 ◎ Great ◎ Inventive Example 10 10 ○ Good ◎ Comparative Example 6 15 Ｘ Bad ◎

As can be seen from [Table 3] above, it was confirmed that the inorganic metal sol contained in the water-soluble lubricating surface treatment coating composition affects the processability and fingerprint resistance. That is, as the content of the inorganic metal sol increased, the coating film became brittle, resulting in a lot of galling phenomenon or powdering, which pushed the coating film during processing, and showed poor fingerprint resistance.

Particularly, in the case of Comparative Example 5 in which 2% by weight of the inorganic metal sol was added, the coating film became too soft, resulting in a resin pushing phenomenon due to galling wear.

Therefore, it was found that the content of the inorganic metal sol that can secure good physical properties and processability is 5 to 10% by weight.

<Experiment 4> Change in physical properties according to the content of metal chelating agent

 A coating composition was prepared according to Inventive Example 6, which showed excellent results in the evaluation of the physical properties of <Experimental Example 2>, and the change in physical properties according to the content of the inorganic metal chelating agent added thereto was observed.

That is, after preparing a test specimen using each water-soluble lubricating surface treatment paint composition, physical properties were evaluated. [Table 4] below shows the results.

Changes in physical properties according to metal chelating agent content division Metal chelating agent Processability Anti-fingerprint Desorption Comparative Example 7 0.1 Δ Great ◎ Inventive Example 11 0.5 ○ Great ◎ Inventive Example 12 1.5 ◎ Great ◎ Inventive Example 13 2 ◎ Good ○ Comparative Example 8 3 ◎ Good Δ

As can be seen from [Table 4] above, in the case of Inventive Examples 11 to 13 in which the metal chelating agent was added according to the present invention, the results showed good or better in all physical properties. On the other hand, in Comparative Example 7 in which 0.1% by weight of the metal chelating agent was added, the result was poor in processability, and in Comparative Example 8 in which 3% by weight was added, the processability was improved, but the result was poor in de-filmability.

Therefore, it is preferable to contain the metal chelating agent in 0.5 to 2% by weight.

<Experimental Example 5> Change in physical properties according to the content of lubricating wax

A coating composition was prepared according to Inventive Example 6, which showed excellent results in the evaluation of the physical properties of <Experimental Example 2>, and the change in physical properties according to the content of the lubricating wax added thereto was observed.

 That is, after preparing a test specimen using each water-soluble lubricating surface treatment coating composition, physical properties were evaluated. [Table 5] below shows the results.

Changes in physical properties according to the content of lubricating wax division Lubrication wax Processability Anti-fingerprint Desorption Comparative Example 9 0.5 Ｘ Great ◎ Inventive Example 14 One ○ Great ◎ Inventive Example 15 5 ◎ Great ◎ Inventive Example 16 10 ◎ Good ◎ Comparative Example 10 15 ○ Bad ◎

As can be seen from [Table 5] above, in Examples 14 to 16 in which the lubricating wax was added according to the present invention, results of good or better were observed in all physical properties. On the other hand, in Comparative Example 9 in which 0.5% by weight of lubricating wax was added, a poor result was seen in processability, and in Comparative Example 10 in which 15% by weight was added, poor results were obtained in fingerprint resistance.

Therefore, it is preferable to contain 1 to 10% by weight of the lubricating wax.

The water-soluble lubricating surface treatment coating composition according to the present invention described above can be used for the production of stainless steel sheet.

That is, as shown in Figure 1, when forming the surface treatment agent coating layer 20 according to the present invention on one or both sides of the stainless steel sheet material 10, to improve the processability, scratch resistance, fingerprint resistance, film release properties Can.

When the dry coating thickness of the surface treatment agent coating layer 20 is less than 1 μm, it is difficult to secure sufficient workability in the stainless steel sheet, and when it exceeds 5 μm, sufficient drying is difficult due to the thick film and the gloss of the stainless steel sheet is deteriorated.

Therefore, the thickness of the surface treatment coating layer 20 is preferably 1 ~ 5μm when dried.

According to the present invention, when processing a stainless steel sheet, there is no need to use a separate lubricant, and a degreasing step for removing the lubricant can also be omitted.

Accordingly, it is possible to simplify the work process to reduce costs and improve productivity.

And when the lubricating surface treatment agent is to be peeled off (de-filmed) after the processing of the stainless steel plate, the surface treatment agent applied to the steel plate with an alkali degreasing agent can be easily dissolved.

In the above, the preferred embodiment of the present invention is exemplarily described, and the scope of the present invention is not limited to the above-described embodiment. Those skilled in the art will understand that various changes and modifications are possible without departing from the scope of the technical spirit of the present invention.

10: Stainless steel sheet material
20: surface treatment agent coating layer

Claims (10)

A water-soluble lubricating surface treatment coating composition applied to one or both surfaces of a stainless steel sheet,
The lubricating surface treatment paint composition, based on the total composition, water-soluble olefin resin 20 to 60% by weight, inorganic metal sol 5 to 10% by weight, lubricating wax 1 to 10% by weight, metal chelating agent 0.5 to 2% by weight % Contained, the balance comprising a solvent, a water-soluble lubricating surface treatment coating composition. According to claim 1,
The water-soluble olefin resin is a water-soluble lubricating surface treatment coating composition, characterized in that the weight average molecular weight is 7,000 to 15,000, and the acid value is 50 to 170 mgKOH / g. According to claim 1,
The inorganic metal sol, a water-soluble lubricating surface treatment coating composition comprising one or two or more selected from the group consisting of silica sol, alumina sol, titania sol, and zirconia sol. The method of claim 3
Water-soluble lubricating surface treatment coating composition, characterized in that the average particle size of the inorganic metal sol is 5 to 30 nm. According to claim 1,
The lubricating wax is selected from the group consisting of paraffin wax, olefin wax, carnauba wax, polyester wax, polyethylen wax, polypropylene wax, polyethylene-teflon wax, and poly teflon wax. Or a water-soluble lubricating surface treatment coating composition comprising two or more. According to claim 1,
The metal chelating agent, a water-soluble lubricating surface treatment coating composition comprising one or two or more selected from the group consisting of silane-based, titanium-based, and zirconium-based. The method of claim 6,
The silane-based chelating agent is vinyl triethoxy silane, 3-glycyloxyproc trimethoxysilane, 3-glycyloxypropyl triethoxysilane, 3-glycyloxypropylmethyl dimethoxy silane, N-2- Water-soluble lubricating surface treatment comprising one or more selected from (aminoethyl) -3-aminopropyl triethoxy silane, 3-aminopropyl trimethoxy silane, and 3-aminopropyl triethoxy silane. Paint composition. The method of claim 6,
The titanium-based chelating agent is a water-soluble lubricating surface, characterized in that it comprises one or two or more selected from titanium acetylacetonate, iso-butoxytitanium ethyl acetoacetate, tetraisopropyl titanate, and tetranormal butyl titanate. Treatment paint composition. The method of claim 6,
The zirconium-based coupling agent, tetra normal-propyl zirconate, tetra normal-butyl zirconate, sodium, potassium, lithium, ammonium salt of zirconium carbonate, triethanol amine zirconate, hexafluoro zirconate 1 A water-soluble lubricating surface treatment coating composition comprising a species or two or more species. The method according to any one of claims 1 to 9,
The water-soluble lubricating surface treatment coating composition is a stainless steel lubricating steel sheet, characterized in that applied to one or both surfaces of the stainless steel sheet to have a dry film thickness of 1 to 5 μm.

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