KR101434918B1 - Method for manufacturing synthetic leather and synthetic leather manufacture by using the same - Google Patents

Abstract

In the present invention, environmentally friendly synthetic leather can be manufactured by manufacturing polyurethane, not by using dimethylformamide or toluene normally used for polymerization of polyurethane, and by using a mixed solvent comprising volatile ketone with the 85°C or less of the boiling point, and using the polyurethane to manufacture the synthetic leather to have no risk of harm caused by the remaining volatile organic solvent.

Description

≪ Desc / Clms Page number 1 > METHOD FOR MANUFACTURING SYNTHETIC LEATHER AND SYNTHETIC LEATHER MANUFACTURE BY USING THE SAME,

The present invention relates to a process for producing an environmentally friendly synthetic leather which does not release harmful components to the human body, and a synthetic leather produced thereby.

Synthetic leather is a product that is used closely in a group or family life, from infants or children to adults. Therefore, synthetic leather should not detect volatile organic compounds and various heavy metal components and organic tin compounds during use. Recently, however, volatile organic compounds (VOC) such as ammonia, di-methyl formamide (DMF), toluene, etc., and harmful substances such as heavy metals and organotin compounds As a result, harmfulness is a problem due to the presence of synthetic leather.

DMF is a compound widely used as a solvent or a durability improver in the chemical industry. However, it is known as a harmful substance that can not be easily released into the body when it is inhaled into the body through eyes, mouth, nose, skin, or the like. Exposure to DMF for a long time can cause liver dysfunction and various carcinogenesis. Therefore, in Europe, DMF is strictly controlled in terms of the content of DMF as 10 mg / kg or less. However, in Korea, synthetic leather fabrics in which DMF is detected in an amount of about 200 to 2,000 ppm or more are used in everyday household goods such as infant products, soaps, chairs, bags, etc., which are very weak in immunity.

Toluene may also cause dermatitis such as nausea, drowsiness, enlargement of the eyes, rashes, liver and kidney damage and neurological disorders when inhaled. In case of prolonged exposure, stomach pain, vomiting, chest pain, (VOC), which is a typical volatile organic compound (VOC). It is sucked into the body through breathing and the like, so that it can be fatal to the human body when it is used in the manufacturing process of synthetic leather which is widely used in daily necessities.

Thermoplastic polyurethane is made by heating pellets to form a film. In this case, however, it is difficult to formulate a variety of pigments. Especially, since it has low heat resistance and low durability, it is mainly used for outdoor film Ethylvinylacetate (EVA) as an adhesive is converted into a viscous semi-liquid phase upon heating at a high temperature. When an EVA adhesive is applied to a thermoplastic polyurethane film, the film is damaged due to a process at a high temperature As a result, it is impossible to apply mass production of synthetic leather. Another method is that EVA is well soluble in toluene, but in this case, toluene has a boiling point of 110.7 ° C and is very low in volatility. As a result, there is a risk of harmfulness due to residual volatile organic compounds.

VOC (Volatile Organic Compound) test method is to measure the concentration of volatile organic compounds vaporized in a constant temperature, constant time, and confined space at a certain temperature, and to express it in "ppm" unit, or after extracting the sample with methanol, MSD method and expressed in units of "mg / kg ". In Europe, it is measured with With reference to EPA 5021, 8260, and GC-MSD method, so that it is consistent with industrial safety standard.

Korean Patent Laid-Open Publication No. 1998-0020342 (published on June 25, 1998)

It is an object of the present invention to provide an environmentally friendly synthetic leather which does not use harmful substances in the process of producing synthetic leather and inevitably discharges harmful substances including a very small amount even during the manufacturing process, And to provide a synthetic leather produced thereby.

It is still another object of the present invention to provide a polyurethane useful in the production of the environmentally-friendly synthetic leather and a process for producing the same.

In order to achieve the above object, according to one embodiment of the present invention, there is provided a polyol composition comprising: a first polyol comprising an ether-based polyol and an ester-based polyol; A second polyol comprising a silicone polyol; An aliphatic first isocyanate; Aromatic second isocyanates; And a modifier comprising a styrene-acrylonitrile resin in a solvent, wherein the solvent comprises a volatile ketone having a boiling point of 85 占 폚 or lower.

The first polyol and the second polyol may be used in a weight ratio of 70:30 to 97: 3.

The first polyol may contain an ester-based polyol and an ether-based polyol in a weight ratio of 30: 1 to 5: 1.

Wherein the silicone polyol is selected from the group consisting of dimethicone, dimethicone copolyol, silicone glycol copolyol, polydimethylsiloxane polyol containing hydroxyl groups at both ends, polydimethylsiloxane polyol having two hydroxyl groups at one end, and mixtures thereof And may have a number average molecular weight (Mn) of 10,000 to 20,000.

The aliphatic first isocyanate compound and the aromatic second isocyanate compound may be used in a weight ratio of 1: 2 to 1: 5.

The volatile ketone may be methyl ethyl ketone.

The solvent may further comprise volatile alcohol.

According to another embodiment of the present invention, there is provided a polyurethane produced by the above-mentioned production method.

According to still another embodiment of the present invention, there is provided a method for forming a film layer, comprising the steps of applying a composition for forming a film layer prepared by mixing the above polyurethane, pigment, solvent and modifier to a release paper and drying to form a film layer on the surface of the release paper ; Applying an adhesive layer-forming composition prepared by mixing the above polyurethane, a crosslinking agent, a solvent, a solvent and a modifying agent onto the film layer, and drying to form an adhesive layer; Placing a working fabric on the adhesive layer and then lapping; A step of winding and aging the processed fabric with the release paper; And separating the aged processed fabric from the release paper, followed by heat treatment, wherein the solvent comprises volatile ketone having a boiling point of 85 캜 or less.

The polyurethane used in the composition for forming a film layer may have a non-volatile component content of 30 1% by weight and a viscosity of 500 to 700 poise / 20 캜.

The polyurethane used for the composition for forming an adhesive layer may have a nonvolatile component content of 70 1% by weight and a viscosity of 600 to 900 poise / 25 占 폚.

In addition, the pigment may be prepared by dispersing the powdery pigment in polyurethane; And a pigment which is mixed with a solvent and pulverized, wherein the polyurethane comprises a first polyol comprising an ether-based polyol and an ester-based polyol; A second polyol comprising a silicone polyol; Aromatic first isocyanates; Aliphatic secondary isocyanate and a styrene-acrylonitrile (SAN) resin in a solvent, and the solvent used in the production of the pigment and the polyurethane is one containing a volatile ketone having a boiling point of 85 ° C or less .

According to another embodiment of the present invention, there is provided a synthetic leather produced by the manufacturing method described above.

Other details of the embodiments of the present invention are included in the following detailed description.

The method for producing synthetic leather according to the present invention is not limited to the process for producing synthetic leather but also uses methyl ethyl ketone (MEK) instead of dimethylformamide and toluene as volatile organic solvents in the production of polyurethane and pigment as raw materials, Further, the solvent can be completely removed through a multistage process during the production process of synthetic leather, thereby making it possible to produce environmentally-friendly synthetic leather. In addition, the synthetic leather produced by the above-described production method is excellent in flexibility, durability, solvent resistance, abrasion resistance, heat resistance and the like, so that it can satisfy various physical properties required by consumers, can be used for various purposes, Lt; / RTI > mat.

FIG. 1 is a schematic view showing a process of manufacturing a synthetic leather according to an embodiment of the present invention.
Fig. 2 is a schematic view showing a polyurethane forming process in Production Example 1; Fig.
Fig. 3 is a schematic view showing the polyurethane formation process in Production Example 2; Fig.

The present invention is capable of various modifications and various embodiments and is intended to illustrate and describe the specific embodiments in detail. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Synthetic leather refers to a sheet-like article obtained by laminating a polyurethane resin composition to a fabric or a knitted fabric. The polyurethane used in the production of such a synthetic leather is usually produced by polymerizing a polyol and an isocyanate together with a chain extender in an organic solvent such as dimethylformamide (DMF), toluene or acetone. However, in the case of organic solvents used in the production of polyurethanes, especially strong solvents such as DMF (boiling point: 153 ° C), they remain in the final synthetic leather to give a high boiling point It is difficult to completely remove the synthetic leather despite the drying and volatilization process by heat treatment at a high temperature during the manufacturing process of the synthetic leather. In order to prevent this, the content of the residual solvent component can be reduced when heated to a temperature above the boiling point of the strong solvent, for example, about 170 ° C or more, but the synthetic leather cloth or polyurethane is deformed, There is a problem of hardness. Also, in the case of toluene, the boiling point is as high as about 110.8 DEG C and is not dissolved in water, so that it is difficult to discharge and remove it in the synthetic leather manufacturing process.

In the present invention, methyl ethyl ketone (MEK) having a low boiling point (about 79.6 ° C.) and high volatility is used instead of a conventional volatile organic solvent in the production of synthetic leather and the synthesis of polyurethane for synthetic leather production, In addition, the synthetic leather is produced by forcibly discharging the solvent used in the manufacturing process of the synthetic leather by a heating process at a temperature higher than the boiling point, thereby producing a synthetic leather having an affinity for harmless to the human body.

That is, the polyurethane according to one embodiment of the present invention comprises: a first polyol comprising an ether-based polyol and an ester-based polyol; A second polyol comprising a silicone polyol; Aromatic first isocyanates; Aliphatic secondary isocyanates; And a modifier comprising a styrene-acrylonitrile (SAN) resin in a solvent containing a volatile ketone having a boiling point of 85 占 폚 or less.

Generally, the polyurethane (i) is prepared by reacting a polyol compound (iii) containing an active hydrogen with an isocyanate compound (ii), as shown in the following reaction scheme 1.

[Reaction Scheme 1]

In Reaction Scheme 1, the kind of the isocyanate and the polyol, which are usable raw materials, is determined depending on the structure of the portion (R, R ') other than the urethane bond.

In the present invention, a mixture of a first polyol comprising an ether-based polyol and an ester-based polyol and a second polyol comprising a silicone polyol as a polyol for synthesis of a polyurethane for producing a synthetic leather is prepared by mixing an isocyanate-based compound and styrene-acrylonitrile SAN) resin, and optionally other additives, in a solvent comprising volatile ketone having a boiling point of 85 占 폚 or less to prepare a polyurethane.

Even when a solvent containing a volatile ketone having a boiling point of 85 캜 or less is used as a solvent for polyurethane polymerization by using a modifier including the above silicone-based polyol and styrene-acrylonitrile (SAN) resin, And it is possible to prevent degradation of durability, solvent resistance, long-term storage property, heat resistance, low-temperature freezing property and flowability, and it is possible to produce polyurethane having excellent physical properties.

Specifically, the first polyol as the polyol usable in the production of the polyurethane according to the present invention comprises an ether-based polyol and an ester-based polyol.

The ether-based polyol may be an aliphatic ether-based polyol such as polypropylene glycol, polyethylene glycol or polytetramethylene glycol, and the ester-based polyol may be adipate, poly (ethylene adipate), poly (diethylene adipate) Based polyol such as poly (propylene adipate), poly (butylene adipate), poly (neopentylene adipate), poly (tetramethylene adipate), or poly (hexamethylene adipate). As the ether-based polyol and the ester-based polyol, a single one or a mixture of two or more of them may be used.

Depending on the type and content of the first polyol to be used, the properties such as elasticity, hydrolysis resistance, low temperature characteristics, thermal stability and abrasion resistance of the finally produced synthetic leather can be determined. Specifically, the ether-based polyol has excellent hydrolysis resistance and low-temperature properties, but is poor in thermal stability and abrasion resistance. On the other hand, the ester-based polyol has excellent abrasion resistance, tear strength, flexibility, heat resistance and elasticity, but low hydrolysis resistance. Accordingly, it may be preferable to appropriately select and mix the ether-type polyol and the ester-type polyol in consideration of the use of the synthetic leather and the physical properties required thereby. Specifically, the ether-based polyol and the ester-based polyol may be mixed and used in a weight ratio of about 30: 1 to 5: 1, or about 20: 1 to 7: 1.

In addition, the second polyol used together with the first polyol includes a silicone polyol.

The silicone polyol is a compound containing a silicon atom (Si) together with a hydroxyl group in a molecule, specifically dimethiconol; Dimethicone copolyol; Silicone glycol copolyols; Or it may be an organopolysiloxane such as polydimethylsiloxane polyol at the end of the polydimethylsiloxane polyol, or one containing a hydroxyl group at each end comprises two hydroxy groups, a commercially available material S1-M445 ^® (Dow coning Co.) Etc. may be used.

More specifically, the silicone polyol may be a polydimethylsiloxane polyol having two hydroxyl groups at only one end of a molecular chain having a polyorganosiloxane skeleton represented by the following formula (1).

[Chemical Formula 1]

R ₁ and R ₂ are each independently an aliphatic hydrocarbon group having 1 to 20 carbon atoms (for example, an alkyl group having 1 to 20 carbon atoms such as a methyl group or an ethyl group, or a cyclopentyl group, a cyclohexyl group, An aryl group having 6 to 12 carbon atoms (e.g., phenyl group, naphthalene group, etc.) and a combination thereof (e.g., benzyl group, etc.) And p may be an integer of 1 or more.

When a polydimethylsiloxane polyol having the above structure is used, a polyurethane containing the polyorganosiloxane skeleton of the above formula (1) can be prepared in the side chain.

The silicone polyol may be a modified silicone polyol obtained by mixing or grafting the above-mentioned organopolysiloxane with another polyol resin. Specifically, the other polyol resin may contain a hydroxyl group and may preferably have a hydroxyl value of about 5 to 300 mg / KOH / g or about 30 to 200 mg KOH / g. More specifically, it may be an acrylic polyol resin satisfying the above-mentioned hydroxyl value, a fluorinated polyol resin, an acrylic modified alkyd resin, an acrylic modified polyester resin, an epoxy resin produced by reaction of bisphenol A and epichlorohydrin, and the like .

When the silicone polyol and the other polyol resin are mixed in the second polyol, the mixing ratio of the silicone polyol to the other polyol resin may be preferably in a weight ratio of 10:90 to 70:30. When the content of the silicone polyol is lower than the above range, the effect of improving the weather resistance and chemical resistance by the silicone polyol is insignificant. When the content is more than 70 parts by weight, the compatibility of the silicone polyol and the other polyol resin may be deteriorated have.

The silicone polyol may preferably have a number average molecular weight (Mn) of 10,000 to 20,000. When the number average molecular weight of the silicone polyol is out of the above range, the compatibility of the silicone polyol with the aliphatic polyol is lowered, and as a result, the stability of the polyurethane finally produced may be deteriorated.

It is preferable that the first polyol and the second polyol including the silicone polyol are used in a weight ratio of 70:30 to 97: 3 or a weight ratio of 80:20 to 95: 5. It is possible to produce a polyurethane having better heat resistance when it is used at the above-mentioned content ratio.

It is preferable that the polyol comprising the first polyol and the second polyol is contained in an amount of 10 to 70% by weight, or 10 to 60% by weight based on 100% by weight of the total amount of the raw materials used for producing the polyurethane have.

On the other hand, a mixture of an aliphatic primary isocyanate and an aromatic secondary isocyanate may be used as the isocyanate-based compound which reacts with the above-mentioned polyol.

Aromatic isocyanates of the aliphatic first specifically, hexamethylene diisocyanate, dicyclohexyl methane diisocyanate or isophorone, and the like isocyanates, if available may be used in commercially available (e. G., SI-M33 ^® (BASF Priest)).

The aromatic second isocyanate is specifically exemplified by methylene bis-4-phenylisocyanate (MDI), toluene 2,4-diisocyanate (TDI), 1,5- 1,5-naphthalene diisocyanate, m- or p-xylene diisocyanate, and the like.

The first and second isocyanates may be mixed and used in a weight ratio of 1: 2 to 1: 5. When included at the above mixing ratio, the physical properties of the polyurethane finally produced can be improved.

The isocyanate compound containing the first and second isocyanates is contained in an amount of 5 to 20% by weight, or 6 to 10% by weight based on 100% by weight of the total amount of raw materials used for producing polyurethane May be desirable.

When the isocyanate compound is reacted with the polyol, the strength, heat resistance and durability of the finally prepared polyurethane increase, but the flexibility decreases. On the other hand, when the content of the isocyanate compound is low, The flexibility is increased but the strength, heat resistance and durability are lowered. Therefore, it may be preferable to suitably adjust the content ratio of the isocyanate compound and the polyol in consideration of the characteristics of the polyurethane required depending on the use of the synthetic leather. Specifically, the mixing ratio of the isocyanate compound containing the first and second isocyanates to the polyol containing the first and second polyols is such that the molar ratio of the isocyanate group (NCO group) to the hydroxyl group (OH group) (NCO / OH , R value) of 0.2 to 1.5, or 0.5 to 1.1.

Meanwhile, the modifier used in the process for producing a polyurethane according to the present invention includes a styrene-acrylonitrile (SAN) resin.

The styrene acrylonitrile resin can be used as a solvent for polyurethane polymerization even when a volatile ketone having a boiling point of 85 ° C or lower is used alone as a solvent for polymerization, and the styrene acrylonitrile resin is free from agglomeration, transparency, durability, solvent resistance, So that it is possible to manufacture polyurethane having excellent physical properties.

The styrene acrylic resin, acrylonitrile may be produced directly, or may be used in commercially available (e. G., SI-M320 ^® (LG, Inc.)).

In addition, the modifier may be used in combination with the styrene-acrylonitrile resin as described above, such as hexanediol diacrylate (HDDA), triethyleneglycol dimethacrylate, or tetraethyleneglycol diacrylate ), Which is usually used in the production of polyurethane.

The modifier may be included in an amount of 1 to 10% by weight, or 4 to 7% by weight based on 100% by weight of the total amount of raw materials used for producing the polyurethane.

As the solvent for the polymerization reaction of the polyol and isocyanate, a solvent containing a volatile ketone having a boiling point of 85 ° C or lower or 80 ° C or lower may be used.

The volatile ketone having a boiling point of 85 ° C or less may be acetone or methyl ethyl ketone (MEK), and MEK may be more preferable.

The solvent may further include a volatile alcohol together with the above-mentioned volatile ketone having a boiling point of 85 캜 or lower. The volatile alcohol may specifically be a volatile monohydric alcohol such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, pentyl alcohol, hexyl alcohol, heptyl alcohol, octyl alcohol, nonyl alcohol and decyl alcohol.

In this case, the volatile alcohol may be contained in an amount of 0.01 to 7% by weight, or 0.05 to 0.1% by weight based on the total weight of the solvent.

The solvent containing the volatile ketone having a boiling point of 85 캜 or less may be contained in an amount of 20 to 80% by weight or 30 to 70% by weight based on 100% by weight of the total amount of raw materials used for producing polyurethane .

The polymerization reaction may be carried out in the presence of a catalyst. Here, the catalyst is not particularly limited as long as it is a catalyst which is usually used in the production of polyurethane by the polymerization reaction of a polyol and an isocyanate compound. Specific examples of the catalyst include triethylamine, tetramethylbutane diamine, dimethylcyclohexylamine, N-methylmorpholine, N, N'-dimethyl-piperazine, 2- (dimethylaminoethoxy) Cyclo- [2.2.2] -octane and the like; Or organometallic compounds such as tin diacetate, tin dioctoate, tin dilaurate, or dibutyltin diacetate, potassium dibutyltin dilaurate acetate, zinc stearate and the like can be used. In addition to the commercially available catalysts include SI-M180 ^® ((Note) Se - ho Tech Co., Ltd.) can be used.

It is preferable that the catalyst is contained in an amount of 0.01 to 1% by weight, or 0.01 to 0.1% by weight based on 100% by weight of the total amount of raw materials used for producing polyurethane.

The polymerization reaction of the polyol and the isocyanate may be carried out in the presence of a chain extender.

The chain extender may be a diol, a diamine, or a hydrazine derivative, as long as it is usually used for the polymerization reaction of a polyurethane. Specific examples of the diol include monoethylene glycol (MEG), propylene glycol, diethylene glycol, dipropylene glycol, neopentyl glycol, ethanediol, methylpentanediol, 1,4-butanediol, Aliphatic diols containing 2 to 14 carbon atoms such as 6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol; Alicyclic diols such as 1,4-cyclohexanediol, and hydrogenated xylylene glycol; And aromatic diols such as xylene glycol. Examples of the amine include ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, N-methylpropylene-1,3-diamine, N, N'- dimethylethylenediamine, hexamethylenediamine, butanediamine , Isophoronediamine, diethylenetriamine, triethylenetetramine, xylenediamine, phenyldiamine, 4,4'-diaminodiphenylmethane and the like. Examples of the hydrazine derivative include hydrazine, adipic acid dihydrazide, and isophthalic acid hydrazide.

When the hydrolysis resistance of the polyurethane is required, it is preferable to use a diol compound as a chain extender. Of these, an aliphatic diol having 2 to 6 carbon atoms, in particular, ethylene glycol May be preferable. When heat resistance of the polyurethane is required, it is preferable to use a diamine compound. Among them, aromatic diamine such as 4,4'-diaminodiphenylmethane may be preferable. Considering the compatibility with solvents and the transparency, durability, heat resistance and the like of the finally produced polyurethane, the use of a mixture of monoethylene glycol (MEG) and 1,6-hexanediol (1.6 HD) as a chain extender May be more preferable.

The chain extender may be included in an amount of 0.3 to 5% by weight, or 0.5 to 3% by weight based on 100% by weight of the total amount of raw materials used for producing polyurethane.

In addition, additives commonly used in polyurethane production, specifically UV absorbers, slip agents, stabilizers, stoppers, antioxidants, antioxidants, flame retardants, hydrolysis inhibitors, light stabilizers, plasticizers; An antistatic agent; A surfactant, and the like.

More specifically, the UV inhibitor may be a benzotriazole-based compound, a benzophenone-based compound, a salicylate-based compound, a cyanoacrylate-based compound, an anilide oxalate compound or the like, and may be commercially available (for example, UV- 6 ^® (manufactured by ZICO)).

The UV inhibitor may be included in an amount of 0.01 to 1% by weight, or 0.05 to 0.1% by weight based on 100% by weight of the total amount of raw materials used for producing polyurethane.

The slip agent may be a fatty acid amide, specifically, a saturated or unsaturated amide, or a saturated or unsaturated alkylene bisamide. More specifically, there may be mentioned propylene oxide siloxane, palmitamide, stearyl arachidamide, stearamidoethylstearamide, stearamidoethylpalmitamide, Erucamide, oleamide, erucamidoethylerucamide, stearamidoethylerucamide, oleoamidoethylerucamide, and the like. The term " anion " may also be used in commercially available, if possible (for example, SN-12 ^® (BASF Co.), ^® Q4-3667 (Dowcorning Co., Ltd.)).

The slip agent may be contained in an amount of 0.1 to 1% by weight, or 0.2 to 0.5% by weight based on 100% by weight of the total amount of raw materials used for producing the polyurethane.

The stabilizer may be benzoic acid or the like and may be preferably 0.01 to 0.5% by weight, or 0.03 to 0.2% by weight based on 100% by weight of the total amount of raw materials used for producing polyurethane .

Examples of the chain terminating agent include alcohols such as methanol (MeOH), octanol or stearyl alcohol; Or amines such as butylamine or stearylamine, and may be preferably 0.01 to 0.5% by weight, or 0.03 to 0.1% by weight based on 100% by weight of the total amount of raw materials used for producing polyurethane .

Examples of the antioxidant include antioxidants (for example, phenol, sulfur, phosphorus, etc.), flame retardants (phosphorous, halogen and inorganic), hydrolysis inhibitors (for example, polycarbodiimide and the like) A hindered amine type, a benzoate type, etc.), a plasticizer; An antistatic agent; Surfactants and the like may further be used.

The method for producing the polyurethane using the above-mentioned components can be carried out according to a conventional method. However, since the physical properties required for the application in which the polyurethane is used vary, it may be desirable to adjust the production conditions accordingly.

Specifically, when the polyurethane according to the present invention is used for forming a film layer in the production of a synthetic leather, the polyurethane has a non-volatile (NV) or solids content of 30 +/- 1 wt% 500 to 700 poise / 20 < 0 > C.

For the production of polyurethanes meeting such physical properties, a first polyol, a second polyol comprising a silicone polyol, and optionally a catalyst, chain extender, or other additives may be added at one time during the reaction, The modifier and the isocyanate compound are preferably subdivided according to the reaction step. The additives such as the first polyol, the second polyol, the isocyanate compound, the modifier, the solvent, the chain extender and the slip agent are preferably added after raising the temperature of the reaction system to about 50 to 90 ° C or 70 to 80 ° C In the case of a catalyst and a conventional modifier, it may be preferable to add the catalyst in a state in which the temperature of the reaction system is kept at 40 ° C or lower.

More specifically, the polyurethane for the film layer contains 40% by weight of the total amount of the second isocyanate, the chain extender and the modifier corresponding to 50% by weight of the total amount of the first and second polyols, the first isocyanate and the second isocyanate (For example, a slipping agent), and then mixed at a temperature of 80 DEG C for 40 minutes, and a solvent in an amount corresponding to 40% by weight of the total amount of the solvent to be used is reacted A first step; After the temperature of the reactant in the first step is lowered, the catalyst is added, and the temperature of the reaction system is further increased to about 80 ° C. Thereafter, the amount of the second isocyanate and the total amount of the solvent used corresponding to 25% by weight of the total amount of the second isocyanate A second step of adding a solvent in an amount corresponding to 40% by weight to react; After the temperature of the reactant in the second step is lowered, a modifier equivalent to 60% by weight of the total amount of the modifier is added. After the temperature of the reaction system is increased to about 80 ° C, the remaining amount (for example, the total amount of the second isocyanate A second isocyanate in an amount corresponding to 25% by weight of the used amount), a solvent in an amount of the remaining amount (for example, an amount corresponding to 20% by weight of the total amount of the solvent) and optionally additives such as a UV inhibitor, And then reacting the resultant mixture. After completion of the reaction in the third step, the temperature of the reaction system is reduced while stirring at a low speed, and the resulting product, that is, the polyurethane can be separated and obtained.

On the other hand, when the polyurethane is used for forming an adhesive layer in the production of a synthetic leather, the polyurethane preferably has a NV of 70 ± 1 wt% and a viscosity of 600 to 900 poise / 25 ° C.

For the production of polyurethanes meeting such physical properties, additives such as aliphatic polyols, silicone polyols, catalysts and slip agents, chain extenders and the like can be added at one time during the reaction, but solvents, modifiers, It is preferable to inject it in a sub-divided manner. The additives such as an aliphatic polyol, a silicone polyol, an isocyanate compound, a modifier, a solvent, a chain extender and a slip agent are preferably added after raising the temperature of the reaction system to about 50 to 90 ° C or 70 to 80 ° C , The catalyst and the conventional modifier may be preferably added while the temperature of the reaction system is kept at 40 DEG C or lower.

More specifically, the adhesive layer polyurethane may contain at least one member selected from the group consisting of an aliphatic polyol, a silicone polyol, a first isocyanate, a second isocyanate corresponding to 50 wt% of the total amount of the second isocyanate, a modifier in an amount of 40 wt% A first step of mixing an additive (for example, a slip agent and the like) at a temperature of 80 DEG C for 40 minutes and adding a solvent in an amount corresponding to 70% by weight of the total amount of the solvent; After the temperature of the reactant in the first step is lowered, the catalyst is added, and the temperature of the reaction system is further increased to about 80 ° C. Thereafter, the amount of the second isocyanate in an amount corresponding to 50% by weight of the total amount of the second isocyanate, A second step of introducing a solvent in an amount corresponding to 30% by weight; Then, the temperature of the reactant in the second step was lowered, and a modifier corresponding to 60% by weight of the total amount of the modifier was added. The temperature of the reaction system was further increased to about 80 DEG C and then additives such as a UV inhibitor and a stabilizer And then reacting the resultant mixture. After completion of the reaction in the third step, the temperature of the reaction system is reduced while stirring at a low speed, and the resulting product, that is, the polyurethane can be separated and obtained.

The polyurethane produced by the above production method has excellent flexibility, mechanical properties, solvent resistance, abrasion resistance and heat resistance. In addition, it is possible to use volatile ketone as a solvent without using dimethylformamide (DMF) and toluene as volatile organic solvents The solvent component can be completely removed during the production process of synthetic leather and is useful for the production of environmentally friendly synthetic leather.

According to another embodiment of the present invention, there is provided an environmentally friendly synthetic leather produced by using the polyurethane and a method for producing the same.

Specifically, the synthetic leather according to one embodiment of the present invention includes a step of applying a composition for forming a film layer, which is prepared by mixing a polyurethane, a pigment, a solvent, and a modifier, to a release paper and then drying to form a film layer on the surface of the release paper Step 1); A step of applying an adhesive layer-forming composition prepared by mixing polyurethane, a crosslinking agent, a catalyst, a solvent and a modifier onto the film layer and then drying to form an adhesive layer (step 2); A step (3) of placing the working fabric on the adhesive layer and then lapping; A step of winding and aging the processed fabric bonded with the release paper (step 4); And separating the aged processed fabric from the release paper, followed by heat treatment (step 5).

FIG. 1 is a schematic view showing a process of manufacturing a synthetic leather according to an embodiment of the present invention. FIG. 1 is an illustration for illustrating the present invention, but the present invention is not limited thereto. Hereinafter, each step will be described in detail with reference to FIG.

In the method for producing synthetic leather according to the present invention, step 1 is a step of forming a film layer on a release paper.

Wherein the film layer comprises a composition for forming a film layer which is prepared by mixing 1-1) polyurethane, 1-2) pigment, 1-3) solvent, 1-4) modifier and optionally 1-5) And then drying it.

In the composition for forming a film layer, 1-1) the polyurethane may be one prepared by the above-described production method, and preferably has a NV of 30 ± 1% by weight and a viscosity of 500 to 700 poise / 20 ° C Polyurethane for film layer.

The above-mentioned 1-2) pigments may be produced by a pigment process in which powdery pigments are mixed with the above-mentioned polyurethane and solvent and pulverized.

In general, a method of diluting and pulverizing polyurethane and a strong solvent such as DMF and toluene is used to pigment the pigment in powder form. On the other hand, in the present invention, the use of polyurethane, a heavy metal-free pigment, and MEK produced according to the above-described method has no risk of environmental hazards due to volatile organic compounds, Can be generated.

The pulverizing process may be carried out according to a conventional pulverizing method such as using a stand mill.

Also, the 1-2) pigment may be used in a dispersed state in a polyurethane-dissolved solution, wherein the NV of the dispersion containing the pigment is 50 ± 1 wt% and the viscosity is 120 to 180 poise / 20 Lt; 0 > C.

Also, it is preferable that 1-3) solvents which can be used in the composition for forming a film layer can be easily removed by a heating process in the production process of synthetic leather. Specifically, the solvent used in the production of the polyurethane, that is, the volatile ketone having a boiling point of 85 ° C or higher may be preferable, and optionally, a volatile alcohol may be further added.

The above-mentioned 1-4) modifier is for improving solvent resistance and neutralization, specifically as described in the above-mentioned modifiers used in the production of polyurethane.

The above respective components may be contained in 1-1) 100 to 20 parts by weight of polyurethane, 1-2) 10 to 50 parts by weight of pigment, 1-3) 70 to 150 parts by weight of solvent and 1 to 30 parts by weight of modifier 1-1) 1-2-30 parts by weight of pigment, 1-3-1) 80-100 parts by weight of solvent, and 1-4-20 parts by weight of modifier, based on 100 parts by weight of polyurethane.

The composition for forming a film layer may further comprise, in addition to the above-mentioned components, 1-5) other additives which are usually used in forming a polyurethane-containing film layer in synthetic leather. Specifically, the UV inhibitor (e.g., benzotriazole-based, benzophenone-based, salicylate-based, cyanoacrylate-based, oxalic anilide-based compound, or UV-6 ^® (ZICO Co.), slip agents (e. G. , ^{® Q4-3667,} (Dow corning Corp.)), a stabilizer (acid (benzoic acid)), blocking agent (or a chain species of payment, e.g., methanol (MeOH) alcohols such as octanol or stearyl alcohols (E.g., amines such as butylamine or stearylamine), antioxidants (e.g., phenolic, sulfuric, phosphorous, etc.), flame retardants (phosphorous, halogenic or inorganic), hydrolysis inhibitors (For example, a hindered amine type, a benzoate type, etc.), a plasticizer, an antistatic agent, a surfactant, and the like can be appropriately selected depending on the use thereof have.

The film layer forming composition may be applied by a conventional method such as spin coating, bar coating, roll coating, slit coating, screen printing, inkjet printing, slide coating, spray coating and the like.

In addition, the release paper may be used without particular limitation as long as it is used in the production of synthetic leather. Specifically, the release paper may be prepared by coating polyvinyl chloride or silicone solution on a paper cloth. The release paper may be embossed.

After the application step, a drying step is carried out to remove the solvent contained in the film layer forming composition. The drying may be carried out by heating or hot air drying in accordance with a conventional method. Specifically, the drying may be carried out at a temperature of 60 to 125 ° C, or about 65 to 120 ° C until the solvent is completely removed have.

Step 2 is a step of forming an adhesive layer on the film layer formed above.

The adhesive layer is formed by mixing 2-1) a polyurethane, 2-2) a crosslinking agent, 2-3) a catalyst, 2-4) a solvent, 2-5) a modifier and optionally 2-6) Applying the composition onto the film layer, and then drying the composition.

In the composition for forming an adhesive layer, 2-1) polyurethane may be prepared according to the above-described production method, and preferably has an NV of 70 +/- 1 wt% and a viscosity of 600 to 900 poise / Lt; / RTI > polyurethane.

The crosslinking agent 2-2) may be a polyisocyanate, a blocked polyisocyanate, an aminoplast, a melamine resin, or the like.

The 2-2) crosslinking agent may be selected from the group consisting of trimethylolpropane-tris- (beta- (normal-aziridinyl) propionate), pentaerythritol-tris- (beta- (normal-aziridinyl) propionate) Of the polyfunctional aziridine compound.

The 2-3) catalyst may be the same as the catalyst described above in the production of the polyurethane.

Further, it is preferable that the solvent which can be used in the composition for forming an adhesive layer can be easily removed by a heating process in the production process of synthetic leather. Specifically, the solvent used in the production of the polyurethane, that is, the volatile ketone having a boiling point of 85 ° C or higher may be preferable.

The above-mentioned 2-5) modifiers are for improving solvent resistance and neutralization, specifically, as described in the above-mentioned modifiers used in the production of polyurethane.

2-1) 10 to 40 parts by weight of a crosslinking agent; 2-3) 1 to 20 parts by weight of a catalyst; 2-4) 70 to 120 parts by weight of a solvent; and 2- 2) crosslinking agent 10-20 parts by weight, 2-3) catalyst 5-15 parts by weight, 2-4) modifier, 80 to 100 parts by weight of a solvent, and 2-5 to 10 to 20 parts by weight of a modifier.

The composition for forming an adhesive layer may further comprise, in addition to the above-mentioned components, 2-6) other additives usually used in the formation of a polyurethane-containing adhesive layer in synthetic leather. Specific examples thereof include the above- 1-5) It is the same as the other additive.

The above-described application and drying step of the composition for forming an adhesive layer can be carried out by the methods as described in the film layer forming step.

However, the drying process is preferably performed by a semi-drying process by heat treatment at a temperature of 100 to 125 ° C, rather than until the solvent in the adhesive layer forming composition is completely removed. Concretely, it is preferable that the application of the solvent in the composition for forming an adhesive layer is carried out until 40 to 80% or 40 to 60% of the solvent is removed.

Step 3 is a step of placing the working fabric on the adhesive layer and then lapping it.

Concretely, on the adhesive layer formed as described above, a fabric woven and processed in accordance with the application is supplied from a laminator machine device, and the fabric is passed through a press roll.

In this case, yarn weaving or processing fabrics such as nylon, cotton, rayon, and polyester may be used as the fabric.

Also, the lapping process may be performed under a pressurizing condition of about 300 to 350 kgf / m < 2 >.

Step 4 is a step of winding and aging the processed fabric lapped with the release paper.

Concretely, in step 3, the release paper and the working fabric lapped by the press press are wound together on a roll. In this case, it is preferable to adjust the width of the bonded release paper and the processed fabric to about 500 to 600 m so that the cross-linked adhesion is easy and the residual organic solvent component can be easily discharged.

After the winding, the aging process is carried out at a temperature of 65 to 70 ° C for about 45 to 50 hours in an aging chamber capable of forced circulation. Since the components of the residual organic solvent may be drained during the aging process, it may be desirable to aged sufficient time to allow the organic solvent component to be completely discharged.

Step 5 is a step of separating the aged processed fabric from the release paper in step 4 and heat-treating the synthetic leather to obtain synthetic leather.

After completion of the aging process in step 4, the fabric joined with the release paper is separated from the release paper by a normal peeling process, and the separated fabric is wound at a very low tension. At this time, the process of winding the processed fabric at a temperature of 20 to 30 DEG C or at room temperature to strengthen the adhesive strength may be selectively performed.

Then, a heat treatment process for forcibly discharging the organic solvent component including MEK that can remain in the processed fabric is performed.

The heat treatment may be performed by a heat treatment at 110 to 130 ° C. Specifically, the heat treatment may be performed by supplying hot air at a temperature as described above in a knit fiber exclusive tenter. At this time, when the set temperature of the tenter is above the boiling point (79.6 ° C) of MEK, the residual organic solvent is easily discharged.

According to the method for producing synthetic leather according to the present invention as described above, it is possible to produce environmentally-friendly synthetic leather. In addition, the synthetic leather produced by the above-described production method is excellent in flexibility, durability, solvent resistance, abrasion resistance, heat resistance and the like, so that it can satisfy various physical properties required by consumers, can be used for various purposes, Lt; / RTI > mat.

Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the following examples are merely illustrative of the present invention, and the contents of the present invention are not limited by the following examples.

Production Example 1

The film-forming polyurethane was produced according to the process as shown in Fig. At this time, raw materials as shown in the following Table 1 were used as base stocks.

In particular, polytetramethylene glycol, overall as an ester-based polyol adipate, silicone polyol (S1-M445 ^®, Dow corning Corp.), the first isocyanate (SI-M33 ^®, BASF Corp.), and the second diisocyanate as ether-based polyol A mixture of ethylene glycol and 1,4-butane diol (MEG + 1.6 HD) as a chain extender, a modifier (SI (methyl methacrylate)) corresponding to 40% by weight of the total amount of the modifier, -M320 ^®, LG Co., Ltd.), and the additives as UV agent (UV-6 ^®, ZICO Co.), slip agents (SN-12 ^®, BASF Corp.) and stabilizers (at a temperature of 80 ℃ then a solution of the benzoic acid) 40 Min. MEK corresponding to 40% by weight of the total amount of MEK was added to the resultant mixture, and the temperature was lowered, and then the catalyst (SI-M180) was added. The temperature of the reaction system was further increased to 80 DEG C, and a second isocyanate (MDI) corresponding to 25 wt% of the total amount of the second isocyanate and MEK corresponding to 40 wt% of the total amount of MEK were further added. It was added to stirred modifier (SI-M320 ^®, LG, Inc.) corresponding to lower the temperature of the reaction system to 60% by weight of modifier the total amount and then, increase the back temperature 80 ℃, 2 25 parts by weight of isocyanate total amount% (UV-6 ^® , ZICO), stabilizers (benzoic acid) and stoppers (MeOH) as additives, and a second isocyanate (MDI) Lt; / RTI > After completion of the reaction, the temperature of the reaction system was decreased, and the polyurethane produced at the same time as the low-speed stirring was separated. The amounts of each of the raw materials were used in the amounts shown in Table 1 below.

The prepared polyurethane had a nonvolatile content (NV) of 30 1% by weight and a viscosity of 500 to 700 poise / 20 캜.

Raw material Content (% by weight) Polyol Ether-based polyol Polytetramethylene glycol 1.42 Ester-based polyol Adipate 10.46 Silicone polyol ^® S1-M445 (Dow coning, Inc.) 2.91 The first isocyanate SI-M33 ^® (manufactured by BASF) 1.87 ± 0.5 The second isocyanate Methylene bis-4-phenylisocyanate (MDI) 6.26 ± 0.5 Chain extender Monoethylene glycol (MEG) 0.77 1,6-hexanediol (1.6HD) 0.79 Modifier SI-M320 ^® (manufactured by LG) 4.96 menstruum Methyl ethyl ketone (MEK) 70 Other additives UV inhibitor UV-6 ^® (ZICO Co.) 0.05 Slip agent SN-12 ^® (BASF Corp.) 0.43 stabilizator Benzoic acid 0.03 catalyst SI-M180 ^® (manufactured by Seho Tech Co., Ltd.) 0.01 Stopper MeOH 0.04

Production Example 2

Polyurethane for forming an adhesive layer was prepared according to the process shown in Fig. At this time, raw materials as shown in the following Table 2 were used as substrate contents.

In particular, polytetramethylene glycol, overall as an ester-based polyol adipate, silicone polyol (S1-M445 ^®, Dow corning Corp.), the first isocyanate (SI-M33 ^®, BASF Corp.), and the second diisocyanate as ether-based polyol a second diisocyanate (TDI), chain extender (a mixture of MEG and 1.4BD), modifiers ^(SI-® M320, LG, Inc.) corresponding to 40% by weight of the total amount modifier, and an additive of 50% by weight of the usage And the slip agent was mixed and reacted at a temperature of 80 캜 for 40 minutes. In the MEK, which corresponds to 70% by weight of MEK to the total amount of the resulting reaction product, which was then added to lower the temperature of the reaction system catalyst (SI-M180 ^®, (Note) Se - ho Tech Co., Ltd.). After the temperature of the reaction system was increased to 80 캜, a second isocyanate (TDI) corresponding to 50% by weight of the total amount of the second isocyanate and MEK corresponding to 30% by weight of the total amount of the MEK were added and mixed. As again it was added a modifier that after lowering the temperature of the reaction system was equal to 60% by weight of the modifying agent total amount (SI-M320 ^®, LG Co., Ltd.), and increasing the temperature of the reaction system to 80 ℃ additive UV agent (UV-6 ^® , Manufactured by ZICO) and a stabilizer (benzoic acid). After completion of the reaction, the temperature was decreased and the resulting polyurethane was separated and obtained at the same time as the low-speed stirring. The amounts of each of the raw materials were used in the amounts shown in Table 2 below.

The resulting polyurethane had an NV content of 70 +/- 1 wt% and a viscosity of 600 to 900 poise / 25 < 0 > C.

Raw material Content (% by weight) Polyol Ether-based polyol Adipate 2.74 Ester-based polyol Polytetramethylene glycol 50.58 Silicone polyol S1-M4450 ^® (manufactured by Dow coning) 3.04 The first isocyanate SI-M330 ^® (manufactured by BASF) 1.24 The second isocyanate Toluene 2,4-diisocyanate (TDI) 5.32 Chain extender Monoethyl glycol (MEG) - 1,4-butanediol (1.4 BD) 0.79 Modifier SI-M3200 ^® (manufactured by LG) 5.84 menstruum Methyl ethyl ketone (MEK) 30 additive UV inhibitor UV-60 ^® (ZICO Co.) 0.08 Slip agent Q4-3667 ^® (Dow coning, Inc.) 0.22 stabilizator Benzoic acid 0.12 catalyst SI-M180 ^® (manufactured by Seho Tech Co., Ltd.) 0.03

Production Example 3: Preparation of Pigment (Pigment Nos. 1 to 11)

Pigments were prepared using the raw materials as described in Table 3 below as base stocks.

Specifically, the polyurethane (PU) prepared in Preparation Example 1, the dye described in the following Table 3, MEK as a solvent, and a stabilizer and a dispersant as additives were put into a mixing container and blended in a primary blend, mill) for 3 hours and 30 minutes to perform high-speed milling. The resultant pulverized product was further added with the polyurethane prepared in Preparation Example 1 and MEK as a solvent, followed by milling for 1 hour and 40 minutes to prepare a pigment. At this time, each raw material was added in the amounts shown in Table 3 below, and the raw materials were accurately weighed with a 1-ton scale when added.

The prepared pigment had a NV of 50 1% by weight and a viscosity of 120 to 180 poise / 20 占 폚.

Pigment
No. Pigment Resin content
(%) Solvent content
(%) Pigment content
(%) Additive content
(%) Type and mixing weight ratio of stabilizer and dispersant One KU-White 1424M 6.5 18.5 ± 1 70 ± 1 5 ①: ②: ④ = 30: 30: 40 2 KU-Yellow 3426M 30 38.5 ± 1 30 ± 1 1.5 ①: ③ = 67: 33 3 KU-Blue 4424M 25 51.5 ± 1 22 ± 1 1.5 ①: ③ = 65: 35 4 KU-Brown 6610M 40 25.5 ± 1 33 ± 1 1.5 ①: ③ = 65: 35 5 KU-Red 5424M 30 53.8 ± 1 15 ± 1 1.2 ①: ③ = 58: 42 6 KU-Red 5425M 30 53.8 ± 1 15 ± 1 1.2 ①: ③ = 58: 42 7 KU-Orange 8516M 40 48.8 ± 1 10 ± 1 1.2 ①: ③ = 58: 42 8 KU-Violet 4510M 40 46.8 ± 1 12 ± 1 1.2 ①: ③ = 58: 42 9 KU-Pink 5516M 40 48.8 ± 1 10 ± 1 1.2 ①: ③ = 58: 42 10 KU-Green 7424M 30 48.5 ± 1 20 ± 1 1.5 ①: ③ = 65: 35 11 SB-924M Black 20 58.5 ± 1 20 ± 1 1.2 ①: ②: ④ = 30: 30: 40

In Table 3, the types of stabilizers and dispersants used are as follows:

①: As a stabilizer, fumed silica (manufactured by OCI)

②: As a stabilizer, dipropylene glycol

③: a dispersing agent, an alkyl ammonium salt of the copolymer of a high molecular weight (BYK ^® 9076, BYK Co.)

④: Copolymer having an acid group as a dispersant (BYK ^® W 9011, manufactured by BYK)

The produced pigments were inspected in the following manner.

Viscosity test: Brookfield viscometer test

Color inspection: stand with full.tint and visual inspection

Dispersibility: diluted in SOL for testing. Inspect with transparent film

After the completion of the test, it was filtered with a # 250 mesh screen and packed in an 18 liter can.

Examples 1 to 11: Preparation of Synthetic Leather

Synthetic leather was prepared according to the process diagram shown in Fig.

Specifically, to 100 parts by weight of the polyurethane prepared in Preparation Example 1, 30 parts by weight of each of the pigments (Pigment Nos. 1 to 11) prepared in Preparation Example 3, 80 parts by weight of MEK as a solvent, SI-M320 < ( ^R ) >, manufactured by ELISA) were mixed to prepare a film layer composition for each pigment type.

The composition for forming a film layer was coated on a release paper using a laminating machine, and dried until the MEK was completely removed by hot air at 65 to 120 캜 to form a film layer.

Next, as the crosslinking agent for the polyurethane to 100 parts by weight was prepared in Preparative Example 2, trimethylolpropane-tris- (beta- (n-aziridinyl) propionate), 10 parts by weight, SI-M180 as a catalyst ^® (Co. Se - ho Tech Co., Ltd.) 5 parts by weight, MEK 80 parts by weight and the modifier ^(SI-® M320, LG Co., Ltd.) 10 parts by weight and mixed for an adhesive layer-forming composition was prepared, and the slurry was coated on the film layer section. The coated adhesive layer forming composition was semi-dried by hot air at 100 to 125 캜 to form an adhesive layer.

A woven nylon fabric was placed on the adhesive layer formed by supplying from the laminating machine mechanism and then laminated while passing through a press at a pressure of 300 to 350 kgf / m < 2 >. The lined releasing paper and the fabric were wound together to a size of about 500 to 600 m and aged for 45 to 50 hours (2 days) while maintaining the temperature at 65 to 70 ° C in the aging room in which the forced mild exhaust was performed. After aging, the release paper and the lined fabric were separated, and the separated fabric was wrapped separately and cooled at room temperature. In order to remove a small amount of MEK remaining in the fabric sufficiently cooled at room temperature and an organic solvent component, a hot hot air of 110 to 130 캜 was slowly supplied from a knit fiber exclusive tenter to remove the residual harmful substances. At this time, the set temperature of the tenter was heated to a temperature higher than the boiling point (79,6 ° C) of the solvent MEK. As a result, synthetic leather was produced.

Comparative Example: Production of Synthetic Leather Using Conventional Polyurethane (PU)

An ether-based polyol polytetramethylene glycol, 1.46% by weight, 11.32% by weight adipate, SI-M33 ^® (BASF Co., Ltd.) 1.87% by weight and as the second isocyanate-methylenebis-4-phenyl-isocyanate 6.26% by weight of a first isocyanate, 4.96% by weight of hexanediol diacrylate as a modifier, 0.77% by weight of monoethyleneglycol as a chain extender and 0.79% by weight of 1,6-hexanediol were mixed and heated to effect polymerization reaction. As after the solvent DMF, toluene, ethyl acetate (EA), acetone and MEK are 4: 2: 2: 2: 1 SI-M180 ® as a solvent, 72 wt% of the catalyst mixed in a mixing volume ratio of (Co. Se - ho Tech Co. ) 0.01% by weight, and as an additive UV agent (UV-6 ^® (ZICO Co., Ltd.)), 0.05% by weight, slip agents (SN-12 ^® (BASF Corp.)), 0.43% by weight of benzoic acid 0.04% by weight and a terminator, as a stabilizer, And 0.04% by weight of methanol were added, respectively, to carry out further reaction to prepare a polyurethane.

Synthetic leather was produced in the same manner as in the above example, except that the polyurethane prepared above was used as a polyurethane for forming a film layer and an adhesive layer.

Test example: VOC test

The synthetic leather specimens prepared in the above Examples and Comparative Examples were respectively extracted with methanol, and the content (mg / kg) of volatile organic compounds was analyzed by GC-MSD method.

As a result, VOC was detected in the case of the synthetic leather produced in the comparative example, but VOC was not detected in the synthetic leather produced in Examples 1 to 11. From these tests, it can be confirmed that the synthetic leather produced by the production method according to the present invention is an environmentally friendly product containing almost no harmful VOC.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit of the invention as set forth in the appended claims. The present invention can be variously modified and changed by those skilled in the art, and it is also within the scope of the present invention.

Claims (13)

A first polyol comprising an ether-based polyol and an ester-based polyol; A second polyol comprising a silicone polyol; Aromatic first isocyanates; An aliphatic secondary isocyanate, and a modifier comprising a styrene-acrylonitrile resin, in a solvent,
Wherein the solvent comprises volatile ketone having a boiling point of 85 占 폚 or less.
The method according to claim 1,
Wherein the first polyol and the second polyol are used in a weight ratio of 70:30 to 97: 3.
The method according to claim 1,
Wherein the first polyol comprises an ether-based polyol and an ester-based polyol in a weight ratio of 30: 1 to 5: 1.

The method according to claim 1,
Wherein the silicone polyol is selected from the group consisting of dimethicone, dimethicone copolyol, silicone glycol copolyol, polydimethylsiloxane polyol containing hydroxyl groups at both ends, polydimethylsiloxane polyol having two hydroxyl groups at one end, and mixtures thereof And has a number average molecular weight (Mn) of 10,000 to 20,000.
The method according to claim 1,
Wherein the aliphatic first isocyanate compound and the aromatic second isocyanate compound are used in a weight ratio of 1: 2 to 1: 5.
The method according to claim 1,
Wherein the volatile ketone is methyl ethyl ketone.
The method according to claim 1,
Wherein the solvent further comprises a volatile alcohol.
delete Applying a composition for forming a film layer, which is prepared by mixing a polyurethane, a pigment, a solvent and a modifier, to a release paper and then drying to form a film layer on the surface of the release paper;
Applying a composition for forming an adhesive layer, which is prepared by mixing a polyurethane, a crosslinking agent, a solvent, a solvent and a modifier, onto the film layer and then drying to form an adhesive layer;
Placing a working fabric on the adhesive layer and then lapping;
A step of winding and aging the processed fabric with the release paper; And
Separating the aged processed fabric from the release paper, and heat treating the aged processed fabric,
Wherein the polyurethane is a polyurethane produced by the process according to claim 1,
Wherein the solvent comprises volatile ketone having a boiling point of 85 캜 or less.
10. The method of claim 9,
Wherein the polyurethane used in the production of the composition for forming a film layer has a non-volatile component content of 30 1% by weight and a viscosity of 500 to 700 poise / 20 캜.
10. The method of claim 9,
Wherein the polyurethane used in the production of the composition for forming an adhesive layer has a nonvolatile component content of 70 1% by weight and a viscosity of 600 to 900 poise / 25 캜.
10. The method of claim 9,
The pigment may be a polyurethane; And a pigmentation process in which the pigment is mixed with a solvent and pulverized,
Wherein the polyurethane comprises a first polyol comprising an ether-based polyol and an ester-based polyol; A second polyol comprising a silicone polyol; Aromatic first isocyanates; An aliphatic secondary isocyanate, and a modifier comprising a styrene-acrylonitrile resin in a solvent,
Wherein the solvent used in the production of the pigment and the polyurethane comprises volatile ketone having a boiling point of 85 캜 or lower.
delete

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