Adhesive coating composition for electrical steel sheet, electrical steel sheet laminate and method for manufacturing electrical steel sheet product

1. An electrical steel sheet adhesive coating composition comprising, on the basis of 100 wt % of total solids:

15 to 60 wt % of a first composition containing an organic resin and an organic/inorganic composite in which inorganic nanoparticles are substituted for an organic resin;

35 to 80 wt % of a second composition containing a metal phosphate and phosphoric acid; and

5 to 10 wt % of a coupling agent,

wherein the coupling agent contains at least one selected from the group consisting of a silane-based coupling agent, a titanate-based coupling agent, and an aluminate-based coupling agent,

wherein the first composition comprises 20 to 70 wt % of the organic resin and 30 to 80 wt % of the organic/inorganic composite on basis of 100 wt % of the first composition,

wherein the second composition comprises 10 to 80 wt % of the metal phosphate and 20 to 90 wt % of the phosphoric acid on basis of 100 wt % of the second composition,

wherein the organic resin comprises at least one selected from the group consisting of an epoxy resin, an ester resin, an acryl-based resin, a styrene resin, a urethane-based resin, an ethylene resin, a phenol resin, and a siloxane resin,

wherein the inorganic nanoparticles comprise at least one selected from the group consisting of SiO 2 , Al 2 O 3 , TiO 2 , MgO, ZnO, CaO, and ZrO 2 ,

wherein the metal phosphate comprises at least one selected from the group consisting of aluminum phosphate monobasic (Al(H 3 PO 4 ) 3 ), cobalt phosphate monobasic (Co(H 3 PO 4 ) 2 ), calcium phosphate monobasic (Ca(H 3 PO 4 ) 2 ), zinc phosphate monobasic (Zn(H 3 PO 4 ) 2 ), and magnesium phosphate monobasic (Mg(H 3 PO 4 ) 2 ).

2. The electrical steel sheet adhesive coating composition of claim 1 , wherein the silane-based coupling agent comprises at least one selected from the group consisting of dimethyldichlorosilane, methyldichlorosilane, methyltrichlorosilane, phenyltrichlorosilane, trichlorosilane, trimethylchlorosilane, silicon tetrachloride, and vinyl trichlorosilane.

3. The electrical steel sheet adhesive coating composition of claim 1 , wherein the titanate-based coupling agent comprises at least one selected from the group consisting of titanium trisostearate isopropoxide isopropyl tri(dioctyl phosphite) titanate, isopropyl trioryl titanate, titanium tris(dodecylbenzenesulfonate) isopropoxide, Isopropyl tri(dioctyl pyrophosphate) titanate, di(dioctyl pyrophosphate) ethylene titanate, and tetraisopropyl di(dioctyl phosphite) titanate.

4. The electrical steel sheet adhesive coating composition of claim 1 , wherein the aluminate-based coupling agent comprises at least one selected from the group consisting of an aluminum-titanium complex, bis(ethyl aceto acetate) aluminum diisopropyl, bis(acetyl acetoate) aluminum diisopropyl, an aluminum acetate coupling agent and isopropyl ester stearoyloxy aluminum.

5. The electrical steel sheet adhesive coating composition of claim 1 , wherein the organic resin comprises at least one selected from the group consisting of benzene, toluene, xylene, naphthalene, anthracene, and benzopyrene as a functional group.

6. The electrical steel sheet adhesive coating composition of claim 1 , wherein the organic resin has a weight-average molecular weight of 1000 to 100,000 and a solid fraction of 10 to 50 wt %.

7. The electrical steel sheet adhesive coating composition of claim 1 , wherein the inorganic nanoparticles are substituted in an amount of 5 to 60 wt % in the organic/inorganic compound.

8. The electrical steel sheet adhesive coating composition of claim 1 , wherein the organic resin comprises the siloxane resin, the urethane-based resin, or the ethylene resin,

the inorganic nanoparticles comprise at least one selected from the group consisting of SiO 2 , Al 2 O 3 , TiO 2 , and ZnO, and

the metal phosphate comprises at least one selected from the group consisting of aluminum phosphate monobasic (Al(H 3 PO 4 ) 3 ) and zinc phosphate monobasic (Zn(H 3 PO 4 ) 2 ).

9. An electrical steel sheet laminate comprising:

a plurality of electrical steel sheets; and

a thermally-bonded layer that is disposed between the plurality of electrical steel sheets,

wherein the thermally-bonded layer comprises 15 to 60 wt % of a first composition containing an organic resin and an organic/inorganic composite in which inorganic nanoparticles are substituted for an organic resin, 35 to 80 wt % of a second composition containing a metal phosphate and phosphoric acid, and 5 to 10 wt % of a coupling agent,

wherein the coupling agent contains at least one selected from the group consisting of a silane-based coupling agent, a titanate-based coupling agent, and an aluminate-based coupling agent,

wherein the first composition comprises 20 to 70 wt % of the organic resin and 30 to 80 wt % of the organic/inorganic composite on basis of 100 wt % of the first composition,

wherein the second composition comprises 10 to 80 wt % of the metal phosphate and 20 to 90 wt % of the phosphoric acid on basis of 100 wt % of the second composition,

wherein the organic resin comprises at least one selected from the group consisting of an epoxy resin, an ester resin, an acryl-based resin, a styrene resin, a urethane-based resin, an ethylene resin, a phenol resin, and a siloxane resin,

wherein the inorganic nanoparticles comprise at least one selected from the group consisting of SiO 2 , Al 2 O 3 , TiO 2 , MgO, ZnO, CaO, and ZrO 2 ,

wherein the metal phosphate comprises at least one selected from the group consisting of aluminum phosphate monobasic (Al(H 3 PO 4 ) 3 ), cobalt phosphate monobasic (Co(H 3 PO 4 ) 2 ), calcium phosphate monobasic (Ca(H 3 PO 4 ) 2 ), zinc phosphate monobasic (Zn(H 3 PO 4 ) 2 ), and magnesium phosphate monobasic (Mg(H 3 PO 4 ) 2 ).

10. A manufacturing method of an electrical steel sheet product, comprising:

preparing the adhesive coating composition of claim 1 ;

coating the adhesive coating composition on a surface of an electrical steel sheet and then curing the same to form an adhesive coating layer;

laminating a plurality of electrical steel sheets where the adhesive coating layer is formed, and thermally bonding the same to form a thermally-bonded layer; and

forming an adhesive layer by performing stress relief annealing on a thermally-bonded electrical steel sheet laminate.

11. The manufacturing method of the electrical steel sheet product of claim 10 , wherein the forming of the adhesive coating layer is carried out in a temperature range of 200 to 600° C.

12. The manufacturing method of the electrical steel sheet product of claim 10 , wherein the forming of the thermally-bonded layer comprises thermal bonding under conditions of a temperature of 150 to 300° C. and a pressure of 0.5 to 5.0 MPa for 0.1 to 120 minutes.

13. The manufacturing method of the electrical steel sheet product of claim 10 , wherein the forming the thermally-bonded layer comprises a temperature increase step and a bonding step, and the temperature increase rate of the temperature increase step is 10° C./min to 1000° C./min.

14. The manufacturing method of the electrical steel sheet product of claim 10 , wherein the forming of the adhesive layer is carried out at a temperature of 500 to 900° ° C. for 30 to 180 minutes.

15. The manufacturing method of the electrical steel sheet product of claim 10 , wherein the forming of the adhesive layer is carried out in a denatured gas or nitrogen N2 gas atmosphere.

16. The manufacturing method of the electrical steel sheet product of claim 10 , wherein the forming of the adhesive layer is carried out in a denatured gas atmosphere that includes a gas containing 10 to 30 vol % of liquefied natural gas (LNG) and 70 to 90 vol % of air.