BINDER COMPOSITION, SLURRY COMPOSITION, AND METHOD FOR COATING SURFACE OF METAL WITH SUPERABSORBENT POLYMER

Abstract

Disclosed are a binder composition, a slurry composition, and a method of coating the surface of a metal with a superabsorbent polymer. Even when the slurry composition contains a large amount of the superabsorbent polymer, the low viscosity thereof can be maintained, thus enabling the uniform coating of the surface of the metal with the superabsorbent polymer. Also, even when a plurality of humidification-drying cycles is repeated in the coating process, no detachment occurs, and thus the superabsorbent polymer can be applied to various fields.

Claims

1. A binder composition, comprising: a urethane-based organic binder; a melamine-based organic binder; a silane coupling agent; and a solvent.

2. The binder composition of claim 1, further comprising at least one of an emulsifying agent and a drying agent.

3. A slurry composition, comprising: the binder composition of claim 1; and superabsorbent polymer particles.

4. The slurry composition of claim 3, wherein the superabsorbent polymer particles are contained in an amount of 60 wt % or less based on a total weight of the slurry composition.

5. The slurry composition of claim 3, wherein the superabsorbent polymer particles are contained in an amount of 40 wt % or less based on a total weight of the slurry composition.

6. A method of coating a surface of a metal with a superabsorbent polymer, comprising: (a) adding superabsorbent polymer particles to the binder composition of claim 1, to prepare a slurry composition; and (b) coating a metal substrate with the slurry composition.

7. The method of claim 6, wherein the superabsorbent polymer particles are contained in an amount of 60 wt % or less based on a total weight of the slurry composition.

8. The method of claim 6, wherein the superabsorbent polymer particles are contained in an amount of 40 wt % or less based on a total weight of the slurry composition.

9. The method of claim 6, wherein the coating is performed using dip coating.

10. The method of claim 6, wherein the coating is performed for 10 sec to 1 min.

Description

EXAMPLES

Preparation Example 1

Preparation of Binder Composition

[0024] 5 g of ethyl alcohol, 5 g of ethyl silicate, 40 g of isopropyl alcohol, 5 g of trimethoxysilane, 10 g of glycidoxypropyl trimethoxysilane, 10 g of melamine-formaldehyde resin, 2.2 g of polyoxyalkylene, 0.3 g of lithium chloride, 0.5 g of water, 12 g of 1-methyl-2-pyrrolidone, and 10 g of polyurethane were mixed, thus preparing a binder composition.

Preparation Example 2

Preparation of Superabsorbent Polymer

[0025] A superabsorbent polymer having a particle size of 50 to 100 μm was prepared.

Preparation Example 3

Preparation of Superabsorbent Polymer

[0026] A superabsorbent polymer having a particle size of less than 50 μm was prepared.

Example 1

Coating of Aluminum Substrate

[0027] (1) Preparation of Slurry Composition

[0028] The binder composition of Preparation Example 1 was added with the superabsorbent polymer having a particle size of 50 to 100 μm of Preparation Example 2, thus preparing a slurry composition. As such, the amount of the superabsorbent polymer that was added was 10 wt % based on the total weight of the slurry composition.

[0029] (2) Coating of Aluminum Substrate

[0030] An aluminum substrate was dip coated for 30 sec with the slurry composition prepared in (1) above and was then dried in an oven at 100° C. for 1 hr, thus coating the aluminum substrate with the superabsorbent polymer.

Example 2

Coating of Aluminum Substrate

[0031] An aluminum substrate was coated with a superabsorbent polymer in the same manner as in Example 1, with the exception that the slurry composition was prepared by adding the binder composition of Preparation Example 1 with the superabsorbent polymer in an amount of 20 wt % based on the total weight of the slurry composition.

Example 3

Coating of Aluminum Substrate

[0032] An aluminum substrate was coated with a superabsorbent polymer in the same manner as in Example 1, with the exception that the slurry composition was prepared by adding the binder composition of Preparation Example 1 with the superabsorbent polymer in an amount of 30 wt % based on the total weight of the slurry composition.

Example 4

Coating of Aluminum Substrate

[0033] An aluminum substrate was coated with a superabsorbent polymer in the same manner as in Example 1, with the exception that the slurry composition was prepared by adding the binder composition of Preparation Example 1 with the superabsorbent polymer in an amount of 40 wt % based on the total weight of the slurry composition.

Example 5

Coating of Aluminum Substrate

[0034] (1) Preparation of Slurry Composition

[0035] The binder composition of Preparation Example 1 was added with the superabsorbent polymer having a particle size of less than 50 μm of Preparation Example 3, thus preparing a slurry composition. As such, the amount of the superabsorbent polymer that was added was 10 wt % based on the total weight of the slurry composition.

[0036] (2) Coating of Aluminum Substrate

[0037] An aluminum substrate was dip coated for 30 sec with the slurry composition prepared in (1) above and was then dried in an oven at 100° C. for 1 hr, thus coating the aluminum substrate with the superabsorbent polymer.

Example 6

Coating of Aluminum Substrate

[0038] An aluminum substrate was coated with a superabsorbent polymer in the same manner as in Example 5, with the exception that the slurry composition was prepared by adding the binder composition of Preparation Example 1 with the superabsorbent polymer in an amount of 20 wt % based on the total weight of the slurry composition.

Example 7

Coating of Aluminum Substrate

[0039] An aluminum substrate was coated with a superabsorbent polymer in the same manner as in Example 5, with the exception that the slurry composition was prepared by adding the binder composition of Preparation Example 1 with the superabsorbent polymer in an amount of 30 wt % based on the total weight of the slurry composition.

Example 8

Coating of Aluminum Substrate

[0040] An aluminum substrate was coated with a superabsorbent polymer in the same manner as in Example 5, with the exception that the slurry composition was prepared by adding the binder composition of Preparation Example 1 with the superabsorbent polymer in an amount of 40 wt % based on the total weight of the slurry composition.

Comparative Example 1

Non-Coated Aluminum Substrate

[0041] An aluminum substrate, which was not coated with any composition, was prepared.

TEST EXAMPLES

Test Example 1

Evaluation of State of Coated Substrate

[0042] The state of the coated aluminum substrate of each of Examples 1 to 8 was observed with the naked eye using an optical microscope (OM, digital camera: OMOS 3M). The results are shown in Table 1 below. In Table 1, O designates a uniform state, Δ designates the state in which agglomeration or cracking was present but had no effect on the coating, and X designates the state in which non-coating or stripping occurred.

TABLE-US-00001 TABLE 1 Test Example 1 (State of coated substrate) Example 1 O Example 2 O Example 3 O Example 4 O Example 5 O Example 6 O Example 7 O Example 8 O C. Example 1 —

Test Example 2

Humidification Performance of Coated Substrate

[0043] The coated aluminum substrates of Examples 1 to 8 and the non-coated aluminum substrate of Comparative Example 1 were allowed to stand in a temperature-and-humidity-controlled oven at a temperature of 32° C. and a humidity of 90% for 1 hr, after which changes in the weight thereof were measured and represented by the percentage values. The results are shown in Table 2 below.

Test Example 3

Dehumidification Performance of Coated Substrate

[0044] The coated aluminum substrates of Examples 1 to 8 and the non-coated aluminum substrate of Comparative Example 1 were allowed to stand in a convection oven at a temperature of 100° C. for 1 hr, after which changes in the weight thereof were measured and represented by the percentage values. The results are shown in Table 2 below.

TABLE-US-00002 TABLE 2 Test Example 2 Test Example 3 (Weight change (%) (Weight change (%) of substrate in test for of substrate in test for humidification dehumidification performance) performance) Ex. 1 4.6 −4.0 Ex. 2 8.1 −2.9 Ex. 3 14.8 −2.9 Ex. 4 24.5 −2.3 Ex. 5 1.5 −4.0 Ex. 6 11.3 −3.0 Ex. 7 15.2 −5.7 Ex. 8 17.5 −3.5 C.Ex. 1 3.9 0.8

Test Example 4

Stability of Substrate

[0045] The tests for humidification performance/dehumidification performance of Test Examples 2 and 3 were repeated for 3 cycles, after which the stability of the coated aluminum substrates (Examples 1 to 8) was observed with the naked eye using an optical microscope (OM, digital camera: OMOS 3M), and the state of each substrate after the tests for humidification performance/dehumidification performance was compared and quantified (0: stripped, 5: slightly stripped and cracked, 10: the same state before humidification/dehumidification). The results are shown in Table 3 below.

TABLE-US-00003 TABLE 3 Test Example 4 (State of substrate after tests for humidification performance/dehumidification performance) Ex. 1 10 Ex. 2 10 Ex. 3 10 Ex. 4 9 Ex. 5 10 Ex. 6 10 Ex. 7 9 Ex. 8 7

[0046] As for Examples 1 to 4 (coating with the slurry composition including the superabsorbent polymer particles having a particle size of 50 to 100 μm), slight cracking occurred in Example 4 using the slurry composition containing 40 wt % of the superabsorbent polymer particles. As for Examples 5 to 8 using the superabsorbent polymer having a particle size of less than 50 μm, cracking, detachment and the like occurred in Examples 7 and 8, but not in Examples 5 and 6. However, such cracking or detachment did not deteriorate the stability of the substrate, and thus did not have any significant influence on the stability of the substrate.

[0047] Based on the results of Test Examples 1 to 4, the aluminum substrates coated with the compositions (Examples 1 to 8) manifested excellent stability, compared to the aluminum substrate not coated with the composition (Comparative Example 1). Also, even when the slurry composition of the invention contained a large amount of the superabsorbent polymer particles, the low viscosity thereof could be maintained, thus enabling the uniform and stable coating of the substrate.