KR100819016B1 - Adhesive for laminate steel plate, method of manufacturing the same and method of laminating steel plate using the same - Google Patents

Abstract

An adhesive for a laminated steel sheet, a method of manufacturing the same, and a method of laminating a steel sheet using the same are disclosed. The adhesive for laminated steel sheets includes polyester-polyurethane resins, block isocyanates and silicone compounds obtained by polymerizing polyesters and isocyanates obtained by polymerizing aromatic dibasic acid compounds, aliphatic dibasic acid compounds and glycols. The adhesive for laminate steel sheet not only has excellent adhesive performance when applied to other synthetic resin films and aluminum films other than PVC, but also has excellent storage stability.

Laminate, steel plate, adhesive

Description

Adhesive for Laminated Steel Sheet, Manufacturing Method thereof and Lamination Method of Steel Sheet Using The Same {ADHESIVE FOR LAMINATE STEEL PLATE, METHOD OF MANUFACTURING THE SAME AND METHOD OF LAMINATING STEEL PLATE USING THE SAME}

The present invention relates to an adhesive for laminated steel sheets, and more particularly to an adhesive for laminated steel sheets having excellent adhesion and storage stability.

Laminated steel sheet formed by coating a synthetic resin film on the steel sheet is not only high in durability, but also resistant to corrosion, is not easily rusted, has little color deformation, and is beautiful in appearance, and is widely used in various interior and exterior materials.

The laminated steel sheet is generally manufactured by coating a soft polyvinyl chloride (PVC) film or the like with an adhesive on a steel sheet plated with zinc or chromium. For example, a roll press method in which a polyvinyl chloride film or the like is attached to a steel sheet and roll-compressed in a state in which the applied adhesive is thermally activated by applying an adhesive to a steel sheet coil and passing it through a drying furnace at a predetermined temperature is widely used. .

The adhesive used in the manufacture of the laminated steel sheet may be divided into a one-component adhesive and a two-component adhesive. As the one-component adhesive, an acrylic adhesive and an acrylic-based adhesive are known, and as the two-component adhesive, a polyester polyol-polyisocyanate-based adhesive is known.

However, the acrylic adhesive has low adhesive strength and impact resistance at low temperatures, and the acrylic-rubber adhesive has disadvantages of low storage stability and adhesive strength. In addition, the polyester polyol-polyisocyanate-based adhesive has a disadvantage of low storage stability.

Accordingly, the technical problem of the present invention is to solve such a conventional problem, and to provide an adhesive for laminated steel sheets having excellent adhesion and storage stability.

Adhesive for laminated steel sheet according to an aspect of the present invention comprises a polyester-polyurethane resin, a block isocyanate and a silicone compound.

For example, the content of the block isocyanate may be 5 to 50 parts by weight, and the content of the silicon compound may be 0.1 to 1 part by weight based on 100 parts by weight of the polyester-polyurethane resin.

The polyester-polyurethane resin may be obtained by polymerizing polyester and isocyanate obtained by polymerizing an aromatic dibasic acid compound, an aliphatic dibasic acid compound and a glycol.

For example, the aromatic dibasic acid compound is a group consisting of terephthalic acid, isophthalic acid, anhydrides thereof, dimethyl terephthalate, dimethyl isophthalate, diethyl terephthalate, diethyl isophthalate, dibutyl terephthalate and dibutyl isophthalate. It may include at least one selected, the aliphatic dibasic acid compound is adipic acid, sebacic acid, isodecyl succinic acid, maleic acid, fumaric acid, monomethyl ester thereof, monoethyl ester, dimethyl ester, diethyl ester and these It may include at least one selected from the group consisting of anhydrides of.

The glycol may include at least one selected from the group consisting of ethylene glycol, propylene glycol, neopentyl glycol, butanediol, polyethylene glycol, diethylene glycol, triethylene glycol, cyclohexanedimethanol, bisphenol A, and derivatives thereof. Preferably bisphenol A and its derivatives in an amount of 1 to 20 mole% of the total glycol.

The isocyanate is diphenylmethane-4,4'-diisocyanate, toluene diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, xylene diisocyanate, 1,5-naphthalene diisocyanate, isophorone diisocyanate, hexamethylene At least one selected from the group consisting of diisocyanate, isopropylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, lidin diisocyanate and methylcyclohexane diisocyanate.

The number average molecular weight of the polyester may be 5,000 to 20,000, the content of the aliphatic dibasic acid compound may be 0.1 to 20 mol% of the total dibasic acid compound. In addition, the number average molecular weight of the polyester-polyurethane resin may be 10,000 to 40,000.

The block isocyanate is diphenylmethane-4,4'-diisocyanate, toluene diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, xylene diisocyanate, 1,5-naphthalene diisocyanate, isophorone diisocyanate, hexa At least one component selected from the group consisting of methylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, lidine diisocyanate and methylcyclohexane diisocyanate is converted into phenol, ketone, oxime and caprolactam systems. It includes the material blocked with at least one blocking agent selected from the group consisting of.

The silicon compound may include a silane compound, wherein the silane compound is a functional group that is easily bonded to an organic material such as PVC, and at least one first selected from the group consisting of vinyl group, amino group, chlorine group, epoxy group, and methacryloxy group. A functional group that can be easily combined with an inorganic material such as a functional group and a steel sheet may include at least one second functional group selected from the group consisting of a chlorine group, a methoxy group and an ethoxy group.

Terminals of the polyester-polyurethane resin may have a hydroxy group, the adhesive is xylene, cyclohexanone, ethyl acetate, methyl ethyl ketone, toluene, isopropyl alcohol, methyl isobutyl ketone, acetone, butyl acetate and cello It may further include at least one solvent selected from the group consisting of sol acetate.

According to the method for producing an adhesive for laminated steel sheets according to an aspect of the present invention, an aromatic dibasic acid compound, an aliphatic dibasic acid compound, and a glycol are polymerized to form a polyester. The polyester is reacted with an isocyanate to form a polyester-polyurethane resin. Next, a block isocyanate and a silicone compound are added to the polyester-polyurethane resin.

The polyester is a first esterification reaction or transesterification using at least one selected from the group consisting of titanium butoxide, dibutyl tin oxide, tetraisopropoxy titanium, magnesium acetate and manganese acetate as a catalyst and at 200 to 240 ° C. Reaction step and the second polycondensation reaction step using at least one selected from the group consisting of titanium butoxide, dibutyl tin oxide, tin acetate, zinc acetate, tin disulfide, antimony trioxide and germanium dioxide as a catalyst at 240 to 280 ℃ It can be prepared through.

According to the lamination method of a steel sheet according to an aspect of the present invention, polyester-polyurethane resin, block isocyanate and silicone obtained by polymerizing polyester and isocyanate obtained by polymerizing aromatic dibasic acid compound, aliphatic dibasic acid compound and glycol on a steel sheet An adhesive comprising a compound is applied, and a film is adhered on the adhesive applied on the steel sheet.

For example, the steel sheet may be heated to 180 to 300 ℃, after attaching the film on the adhesive, it may be pressed by pressing the film.

As described above, the adhesive for laminate steel sheet has excellent adhesion performance as well as excellent storage stability even when applied to other synthetic resin films and aluminum films other than polyvinyl chloride (PVC) film.

Hereinafter will be described in detail with respect to the adhesive for laminate steel sheet according to an embodiment of the present invention.

Adhesive for Laminate Steel Sheet

Adhesive for laminated steel sheet according to an embodiment of the present invention comprises a polyester-polyurethane resin, a block isocyanate and a silicone compound.

The polyester-polyurethane resin may be obtained by polymerizing an aromatic dibasic acid compound, an aliphatic dibasic acid compound, glycol and isocyanate.

More specifically, the aromatic dibasic acid compound, the aliphatic dibasic acid compound and the glycol is reacted to prepare a polyester, and the polyester and the isocyanate are reacted to prepare a polyester-polyurethane resin.

The terminal of the polyester has a hydroxy group, for this purpose, it is preferable that the reaction molar ratio of the total dibasic acid compound and the glycol is about n: n + 1.

The aromatic dibasic acid compound may include at least one selected from the group consisting of aromatic dibasic acids, alkyl esters thereof, and acid anhydrides. More specifically, examples of the aromatic dibasic acid include terephthalic acid and isophthalic acid. Examples of the alkyl ester of the aromatic dibasic acid include dimethyl terephthalate, dimethyl isophthalate, diethyl terephthalate, diethylisophthalate, and dibutyl. Terephthalate, dibutyl isophthalate, etc. are mentioned. The aromatic dibasic acid and its alkyl ester and acid anhydride may be used alone or in combination of two or more.

The aliphatic dibasic acid compound may include at least one selected from the group consisting of aliphatic dibasic acids, alkyl esters thereof, and acid anhydrides. More specifically, the aliphatic dibasic acid may include adipic acid, sebacic acid, isodecyl succinic acid, maleic acid, fumaric acid, and the like, and the alkyl ester may be a monomethyl ester or a monoethyl ester of the aliphatic dibasic acid. , Dimethyl ester, diethyl ester and the like can be given. The aliphatic dibasic acid and its alkyl ester and acid anhydride may be used alone or in combination of two or more. For example, the aliphatic dibasic acid compound may be about 0.1 to 20 mol% of the total dibasic acid compound.

As the glycol, ethylene glycol, propylene glycol, neopentyl glycol, butanediol, polyethylene glycol, diethylene glycol, triethylene glycol, cyclohexanedimethanol, bisphenol A, and derivatives thereof may be used. These can be mixed and used. Preferably, the glycol may include bisphenol A and its derivatives, and the content of the bisphenol A and its derivatives is preferably about 1 to 20 mol% of the total glycol.

In more detail the process of obtaining the polyester, the aromatic dibasic acid compound, the aliphatic dibasic acid compound and the glycol is put in a reactor and heated to a predetermined temperature to cause an esterification reaction or a transesterification reaction. The heating temperature in the reaction is preferably about 200 to 240 ℃ in consideration of the reaction rate and degree of polymerization. In the esterification reaction or transesterification reaction, water is generated as an accompaniment, and the reaction is preferably performed while removing the water to facilitate the reaction.

In the reaction, a catalyst may be used to facilitate the reaction. As the catalyst, for example, titanium butoxide, dibutyl tin oxide, tetraisopropoxy titanium, magnesium acetate, manganese acetate and the like can be used.

Next, the ester obtained by the said esterification reaction or transesterification reaction is polycondensed, and the polyester which has an appropriate molecular weight is obtained. The number average molecular weight of the polyester may be, for example, about 5,000 to 20,000. In the ester polycondensation, since glycol is generated as a by-product, it is preferable to react while removing the glycol to facilitate the reaction. The polycondensation reaction is preferably made at about 240 to 280 ℃, it can be made through a nitrogen method, nitrogen decompression method, high vacuum method and the like.

In the polycondensation reaction, a catalyst may be used so that the reaction proceeds easily. As the catalyst, for example, titanium butoxide, dibutyl tin oxide, tin acetate, zinc acetate, tin disulfide, antimony trioxide, germanium dioxide and the like can be used.

Next, the polyester is reacted with an isocyanate to prepare a polyester-polyurethane resin. As for the number average molecular weight of the said polyester-polyurethane resin, about 10,000-40,000 are preferable, for example.

As said isocyanate, diphenylmethane-4,4'- diisocyanate, toluene diisocyanate, 4,4'- diphenyl dimethyl methane diisocyanate, xylene diisocyanate, 1, 5- naphthalene diisocyanate, iso Poron diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, lidin diisocyanate, methylcyclohexanediisocyanate, and the like, each of which may be used alone or in combination of two or more. Can be used.

Since the isocyanate has a high reactivity, the reaction between the polyester and the isocyanate is performed at a lower temperature than the reaction for producing the polyester, for example, preferably at about 60 to 100 ° C.

In the above reaction, an excess of polyester and the isocyanate react, and the terminal of the polyester-polyurethane resin has a hydroxyl group. When the terminal of the polyester-polyurethane resin has an isocyanate group, the storage stability may be greatly reduced due to the high reactivity of the isocyanate group.

Next, a block isocyanate and a silicone compound are added to the polyester-polyurethane resin.

The blocked isocyanate dissociates in the process of laminating the steel sheet and the film using the adhesive, and reacts with the polyester-polyurethane resin and moisture in the air to cure the adhesive.

The block isocyanate is, for example, diphenylmethane-4,4'-diisocyanate, toluene diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, xylene diisocyanate, 1,5-naphthalene diisocyanate, iso Poron diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, lidin diisocyanate, methylcyclohexane diisocyanate or mixtures thereof, and the like, and phenolic, ketone, oxime and caprolactam Blocking with a blocking agent such as a system may be used, and these may be used alone or in combination of two or more.

The silicone compound improves the adhesion and heat resistance of the adhesive and the steel sheet to which the adhesive is applied.

The silicon compound may be, for example, a silane compound, and more specifically, may include a first functional group that is easily bonded with an organic material and a second functional group that is easily bonded with an inorganic material. The first functional group may include, for example, a vinyl group, an amino group, a chlorine group, an epoxy group, a methacryloxy group, and the like, and the second functional group may include a chlorine group, a methoxy group, an ethoxy group, or the like. . Therefore, the silicone compound may have a strong adhesion to both the synthetic resin film and the steel sheet.

In the adhesive for laminate steel sheet, the content of the block isocyanate with respect to 100 parts by weight of the polyester-polyurethane resin may be about 5 to 50 parts by weight based on 100 parts by weight of the polyester-polyurethane resin, the silicone compound 0.1 To 1 part by weight.

In addition, the adhesive for laminate steel sheet may further include a solvent. For example, xylene, cyclohexanone, ethyl acetate, methyl ethyl ketone, toluene, isopropyl alcohol, methyl isobutyl ketone, acetone, butyl acetate, cellosolve acetate, etc. may be used as the solvent, and these may be used alone or in combination. Two or more may be used in combination.

Hereinafter, the lamination method of the steel sheet according to an embodiment of the present invention will be described in detail.

Lamination Method of Steel Sheet

The method of laminating a steel sheet according to an embodiment of the present invention includes applying an adhesive including a polyester-polyurethane resin, a block isocyanate, and a silicone compound to the steel sheet and adhering a film on the adhesive.

The polyester-polyurethane resin may be obtained by polymerizing an aromatic dibasic acid compound, an aliphatic dibasic acid compound, glycol and isocyanate. The content of the block isocyanate based on 100 parts by weight of the polyester-polyurethane resin may be about 5 to 50 parts by weight based on 100 parts by weight of the polyester-polyurethane resin, and 0.1 to 1 parts by weight of the silicone compound.

In addition, the adhesive may further include a solvent. For example, xylene, cyclohexanone, ethyl acetate, methyl ethyl ketone, toluene, isopropyl alcohol, methyl isobutyl ketone, acetone, butyl acetate, cellosolve acetate, etc. may be used as the solvent, and these may be used alone or in combination. Two or more may be used in combination. Since the adhesive including the polyester-polyurethane resin, the block isocyanate and the silicone compound is substantially the same as the adhesive for the laminate steel sheet described above, a detailed description thereof will be omitted.

First, the adhesive is applied onto a predetermined steel sheet, and the steel sheet coated with the adhesive is heated to a predetermined temperature. Thereafter, the film is attached onto the adhesive, and then the film is compressed.

For example, the coating amount of the adhesive may be about 4 to 15 g / m ² , the coating amount of the adhesive and the heating temperature of the steel sheet may vary depending on the type of the steel sheet and the type of the film. For example, a galvanized steel sheet (GI steel sheet), a cold rolled steel sheet (CR steel sheet), an electrogalvanized steel sheet (EGI), etc. may be used as the steel sheet, and the film may be a polyvinyl chloride (PVC) film or polyethylene tere. Phthalate (PET) films, polypropylene (PP) films, polyethylene (PE) films, aluminum films or multilayer films in which one or more of them are laminated may be used. Table 1 below shows the preferred coating amount and heating temperature of the steel sheet when the adhesive is applied to the galvanized steel sheet (GI steel sheet).

Table 1

Steel plate temperature (℃) Coating amount (g / m ² ) Soft PVC film About 150 to 200 About 4 to 7 Rigid PVC film About 150 to 200 About 4 to 7 PET-ink / PVC film, PET-ink / PP film, PET-ink / PE film About 150 to 250 About 4 to 7 PET / Aluminum / PVC Film About 150 to 250 About 4 to 7 Aluminum film About 150 to 250 About 7 to 15 PET film About 150 to 250 About 4 to 7

When the cold rolled steel sheet or the electrogalvanized steel sheet is used as the steel sheet, the heating time of the steel sheet is preferably about 30 to 60 seconds.

The steel sheet coated with the adhesive is heated, and then a predetermined film is attached and pressed with a roller or the like. In this process, the block isocyanate reacts with the polyester-polyurethane resin and moisture in the air so that the adhesive is cured so that the film firmly adheres to the steel sheet.

After the PVC film was adhered to the zinc steel sheet by using an adhesive for a laminated steel sheet and a lamination method of the steel sheet according to an embodiment of the present invention, an Ericsson test was performed. More specifically, after forming a square (#)-shaped cutoff of about 5mm intervals on the surface of the PVC film, and pressurizing the zinc steel sheet using a spherical body, the spherical body is moved about 8mm from the reference surface where the pressing started When the peeling of the PVC film was observed, the peeling phenomenon did not appear. In addition, the Ericsson test was performed on the zinc steel sheet to which the PET film and the aluminum film were adhered in the same manner, but no peeling phenomenon was observed.

In addition, the change was observed after leaving the adhesive for laminated steel sheet at room temperature for about 6 months, but no external change such as phase separation or a sharp increase in viscosity was observed.

According to the present invention as described above, the adhesive for laminate steel sheet not only has excellent adhesive performance when applied to other synthetic resin films and aluminum films other than PVC, but also has excellent storage stability.

In the detailed description of the present invention described above with reference to a preferred embodiment of the present invention, those skilled in the art or those skilled in the art having ordinary knowledge in the scope of the invention described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

Claims (25)

Polyester-polyurethane resin obtained by polymerizing polyester and isocyanate obtained by polymerizing an aromatic dibasic acid compound, an aliphatic dibasic acid compound and a glycol; Blocked isocyanates; And Adhesive for laminated steel sheet containing a silicone compound. The adhesive for laminate sheet according to claim 1, wherein the content of the block isocyanate is 5 to 50 parts by weight and the content of the silicon compound is 0.1 to 1 part by weight based on 100 parts by weight of the polyester-polyurethane resin. delete The method of claim 1, wherein the aromatic dibasic acid compound is composed of terephthalic acid, isophthalic acid, anhydrides thereof, dimethyl terephthalate, dimethyl isophthalate, diethyl terephthalate, diethyl isophthalate, dibutyl terephthalate and dibutyl isophthalate Adhesive for laminate sheet, characterized in that it comprises at least one selected from the group. The method of claim 1, wherein the aliphatic dibasic acid compound is adipic acid, sebacic acid, isodecyl succinic acid, maleic acid, fumaric acid, monomethyl esters thereof, monoethyl esters, dimethyl esters, diethyl esters and anhydrides thereof. Adhesive for laminate sheet steel, characterized in that it comprises at least one selected from the group consisting of. The method of claim 1, wherein the glycol is at least one selected from the group consisting of ethylene glycol, propylene glycol, neopentyl glycol, butanediol, polyethylene glycol, diethylene glycol, triethylene glycol, cyclohexanedimethanol, bisphenol A and derivatives thereof. Adhesive for laminate sheet steel, characterized in that it comprises. The adhesive for laminate sheet according to claim 6, wherein the content of bisphenol A and its derivatives is 1 to 20 mol% of the total glycol. The method of claim 1, wherein the isocyanate is diphenylmethane-4,4'-diisocyanate, toluene diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, xylene diisocyanate, 1,5-naphthalene diisocyanate, iso Adhesive for laminated steel sheet, characterized in that it comprises at least one selected from the group consisting of poron diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, lidin diisocyanate and methylcyclohexane diisocyanate . The adhesive for laminate steel sheet according to claim 1, wherein the polyester has a number average molecular weight of 5,000 to 20,000. The adhesive for laminate sheet according to claim 1, wherein the content of the aliphatic dibasic acid compound is 0.1 to 20 mol% of the total dibasic acid compound. 2. The adhesive for laminate steel sheet according to claim 1, wherein the polyester-polyurethane resin has a number average molecular weight of 10,000 to 40,000. The method of claim 1, wherein the blocked isocyanate is diphenylmethane-4,4'- diisocyanate, toluene diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, xylene diisocyanate, 1,5-naphthalene diisocyanate, At least one component selected from the group consisting of isophorone diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, lidin diisocyanate and methylcyclohexane diisocyanate is selected from the group consisting of phenol, ketone, Adhesive for laminate sheet, characterized in that it comprises a material blocked with at least one blocking agent selected from the group consisting of oxime system and caprolactam system. The adhesive for laminate steel sheet according to claim 1, wherein the silicone compound comprises a silane compound. The method of claim 13, wherein the silane compound is at least one first functional group selected from the group consisting of vinyl group, amino group, chlorine group, epoxy group and methacryloxy group and at least one selected from the group consisting of chlorine group, methoxy group and ethoxy group An adhesive for laminated steel sheets, comprising a second functional group. delete The method of claim 1, further comprising at least one solvent selected from the group consisting of xylene, cyclohexanone, ethyl acetate, methyl ethyl ketone, toluene, isopropyl alcohol, methyl isobutyl ketone, acetone, butyl acetate and cellosolve acetate. Adhesive for laminate sheet steel, characterized in that it comprises. Polymerizing the aromatic dibasic acid compound, the aliphatic dibasic acid compound and the glycol to form a polyester; Reacting the polyester with an isocyanate to form a polyester-polyurethane resin; And Method for producing a laminate sheet adhesive comprising the step of adding a block isocyanate and a silicone compound to the polyester-polyurethane resin. The method of claim 17, wherein forming the polyester, A first reaction step performed at 200 to 240 ° C. using at least one selected from the group consisting of titanium butoxide, dibutyl tin oxide, tetraisopropoxy titanium, magnesium acetate and manganese acetate as a catalyst; And Comprising a second reaction step using at least one selected from the group consisting of titanium butoxide, dibutyl tin oxide, tin acetate, zinc acetate, tin disulfide, antimony trioxide and germanium dioxide as a catalyst and at 240 to 280 ° C. A method for producing an adhesive for laminate steel sheet, characterized by the above-mentioned. Applying an adhesive comprising polyester-polyurethane resin, block isocyanate and silicone compound obtained by polymerizing polyester and isocyanate obtained by polymerizing aromatic dibasic acid compound, aliphatic dibasic acid compound and glycol on a steel sheet; And Laminating method of the steel sheet comprising the step of adhering a film on the adhesive applied on the steel sheet. 20. The method of claim 19, further comprising heating the steel sheet. The method of claim 20, wherein the heating temperature of the steel sheet is 180 to 300 ℃. 20. The method of claim 19, wherein the amount of the adhesive applied is 4 to 15 g / m ² . 20. The method of claim 19, wherein the steel sheet is any one selected from the group consisting of a cold rolled steel sheet, a galvanized steel sheet, and an electrogalvanized steel sheet. 20. The method of claim 19, wherein the film is any one selected from polyvinyl chloride film, polyethylene terephthalate film, polypropylene film, polyethylene film, aluminum film and a multilayer film in which at least two or more of them are laminated. Laminate method. The method of claim 19, wherein the step of adhering the film, Attaching the film on the adhesive; And Pressing the film by pressing the laminate method of the steel sheet characterized in that it comprises a.