JP2009185260A - Surface layer material-forming composition for fiber laminate, synthetic/artificial leather using the same, and method for producing synthetic/artificial leather - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface layer material-forming composition for a fiber laminate having well-balanced strength and flexibility and allowing environment-friendly production, and to provide synthetic leather using the same. <P>SOLUTION: In the surface layer material-forming composition for a fiber laminate consisting of a base compound A and a curing agent B, the base compound A is polycarbonate diol (PCD) obtained from 1,6-hexanediol (HD) and low-molecular carbonate, while the curing agent B consists of modified polyisocyanate B1 of hexamethylene diisocyanate (HDI) having the number average molecular weight of 350-500 and the average functional group number (f) of 2≤f<3 and isocyanurate-modified polyisocyanate B2 of HDI having the average functional group number of f≥3, and a mass ratio between B1:B2 is 50:50 to 95:5. Both the base compound A and the curing agent B contain no organic solvent. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a composition for forming a surface layer material for a fiber laminate, synthetic leather or artificial leather using the same, and a method for producing synthetic leather or artificial leather. More specifically, the composition for forming a surface layer material for a fiber laminate, which has an excellent balance between strength and flexibility and is environmentally friendly during production, and synthetic leather or artificial leather using the same, and a method for producing synthetic leather or artificial leather About.

  Synthetic leather and artificial leather are used for bags and shoes, for example. Synthetic leather is required to have flexibility, impact resilience, strength, stretchability, and breathability from the usage environment and conditions.

  On the other hand, in such a method for producing synthetic leather or artificial leather, a method of coating directly on a base fabric or the like or coating on a release paper and then transferring to a base fabric is common. For this reason, when organic solvents evaporate when coating the coating resin composition, environmental problems and occupational safety and health problems occur, and equipment for countermeasures against this problem is required, and capital investment is increased. There was a problem such as swelling.

  Therefore, Patent Document 1 proposes coating a synthetic leather or the like with an aqueous polyurethane coating agent.

JP 2006-104251 A

  However, the production system using the aqueous coating agent has a problem that the energy cost increases due to the high evaporation energy of water. A coating agent for synthetic leather or the like that satisfies all of productivity, strength, and environmental response has not been obtained.

  The present invention provides a composition for forming a surface layer material for a fiber laminate, which has an excellent balance between strength and flexibility and is environmentally friendly during production, and synthetic leather or artificial leather using the same, and a method for producing synthetic leather or artificial leather The purpose is to provide.

  That is, this invention is shown by the following (1)-(7).

(1) Polycarbonate diol in which the main agent (A) is composed of 1,6-hexanediol and a low-molecular-weight carbonate in the surface layer material-forming composition for a fiber laminate composed of the main agent (A) and the curing agent (B) And the curing agent (B) is a modified polyisocyanate (B1) of hexamethylene diisocyanate having a number average molecular weight of 350 to 500 and an average functional group number (f) of 2 ≦ f <3, and hexamethylene of f ≧ 3 The diisocyanate isocyanurate-modified polyisocyanate (B2), (B1) :( B2) = 50: 50 to 95: 5 (mass ratio), and the main agent (A) and the curing agent (B). A surface layer-forming composition for fiber laminates, characterized in that both do not contain an organic solvent.

(2) The surface layer material-forming composition for a fiber laminate according to (1), wherein (B1) is an allophanate-modified isocyanate obtained from monool and hexamethylene diisocyanate.

(3) A synthetic leather comprising a surface layer and a fiber fabric layer formed from the surface layer material-forming composition for a fiber laminate according to (1) or (2).

(4) An artificial leather comprising a surface layer formed from the surface layer material-forming composition for a fiber laminate (1) or (2) and a fiber fabric layer.

(5) A liquid containing the main component (A) and the curing agent (B) of (1) or (2) above is applied to a releasable support, subjected to primary curing, and then bonded to a fiber fabric and secondarily cured. A method for producing synthetic leather or artificial leather, comprising removing the releasable support.

(6) A synthetic leather or artificial leather characterized in that a liquid containing the main agent (A) and the curing agent (B) of (1) or (2) is directly applied to a fiber fabric and heat-cured. Production method.

(7) In the liquid which mix | blended the main ingredient (A) of said (1) or (2), and the hardening | curing agent (B), the molar ratio of the hydroxyl group and isocyanate group of the said mixing liquid is hydroxyl group / isocyanate group = 90 / 100- The method for producing synthetic leather or artificial leather according to (5) or (6) above, wherein the ratio is 110/100.

  INDUSTRIAL APPLICABILITY According to the present invention, a composition for forming a surface layer material for a fiber laminate, which is excellent in balance of productivity / strength and flexibility, and friendly to the global environment, and production of synthetic leather or artificial leather and synthetic leather or artificial leather using the same It became possible to provide a method.

  In the present invention, hexamethylene diisocyanate (hereinafter referred to as HDI) in which the main agent (A) is a specific polycarbonate diol (hereinafter abbreviated as PCD) and the curing agent (B) has a number average molecular weight of 350 to 500 and a low functional group number. (Abbreviated) modified polyisocyanate (B1) and HDI isocyanurate-modified polyisocyanate (B2).

  PCD in the main agent (A) used in the present invention is PCD obtained by dealcoholization reaction or dephenol reaction of 1,6-hexanediol (hereinafter abbreviated as 1,6-HD) and a low molecular carbonate. . The number average molecular weight of this PCD is preferably 500 to 5,000, more preferably 1,000 to 3,000. When the number average molecular weight is too low, the flexibility of the coating agent is lowered, and the touch on the skin and the followability with the substrate are lowered. On the other hand, when the number average molecular weight is too high, the film strength tends to be insufficient.

  In the production, PCD obtained using a low molecular polyol other than 1,6-HD can also be used in combination with the main agent (A) of the coating agent of the present invention. Low molecular polyols other than 1,6-HD include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butane. Diol, 1,5-pentanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 2-ethyl-4-butyl-1,3-propanediol, diethylene glycol , Dipropylene glycol, neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, ethylene oxide or propylene oxide adduct of bisphenol A, bis (β-hydroxyethyl) benzene, Xylylene glycol, glycerin, trimethylo Trimethylolpropane, low molecular polyols such as pentaerythritol, and the like.

  Examples of the low molecular carbonate include ethylene carbonate, diethyl carbonate, and diphenyl carbonate.

  The use of the chain extender is not a problem as long as it is mixed and used immediately before the blending of the main agent and the curing agent. However, if a polyol premix is used in advance, an ester exchange reaction occurs during storage, which is not preferable.

  The curing agent (B) in the present invention is composed of a modified polyisocyanate (B1) of HDI having a number average molecular weight of 350 to 500 and a low functional group number, and an isocyanurate modified polyisocyanate (B2) of HDI.

  The modified polyisocyanate (B1) of HDI having a number average molecular weight of 350 to 500 and a low functional group number imparts flexibility to the coating and brings about an effect of improving workability when forming the surface layer material.

  When the number average molecular weight of (B1) is less than the lower limit, an odor problem may occur during the surface layer material forming operation. When the upper limit is exceeded, the viscosity increases, and the productivity during the surface layer material forming operation decreases.

  The average functional group number (f) of (B1) is 2 ≦ f <3. When f is less than the lower limit, the crosslinking effect is insufficient and the film properties are deteriorated. Above the upper limit, the flexibility of the coating decreases.

  Specific examples of (B1) include 1: 2 (molar ratio) adduct of low molecular glycol (molecular weight 62 to 164) and HDI, 1: 1 of low molecular monool (molecular weight 32 to 164) and HDI. 2 (molar ratio) allophanate modified body etc. are mentioned. In the present invention, a 1: 2 (molar ratio) allophanate modified product of a low-molecular monool and HDI having a low viscosity is preferred.

  Low molecular monools include methanol, ethanol, propanol (including various isomers), butanol (including various isomers), pentanol (including various isomers), hexanol (including various isomers), heptanol ( And saturated aliphatic monools such as octanol (including various isomers), nonanol (including various isomers), and unsaturated aliphatic monools having 2 to 9 carbon atoms. The low molecular weight monool preferred in the present invention is isopropanol having a small molecular weight and a high shielding effect.

  A specific method for producing an allophanate modified product of HDI is to add a catalyst poison after reacting HDI at least twice the molar equivalent with respect to a hydroxyl group and monool in the presence of an allophanate catalyst. In this manufacturing method, unreacted HDI is removed.

  The isocyanurate-modified polyisocyanate (B2) of HDI is obtained by removing unreacted HDI from HDI or a partial urethane prepolymer of HDI through an isocyanuration reaction. Here, the partial urethane prepolymer of HDI is obtained by urethanation of an excess amount of HDI and a low molecular glycol with respect to the hydroxyl group, and the charged molar ratio is HDI: low molecular glycol = 5: 1. ~ 100: 1 is preferred. The low molecular glycol is preferably 1,3-butanediol in consideration of the compatibility of the obtained polyisocyanate and the isocyanate content of the polyisocyanate to be obtained.

  A polyisocyanate other than (B1) and (B2) can be used in combination with the curing agent (B) as necessary. Specifically, diphenylmethane diisocyanate (including various isomers), tolylene diisocyanate (including various isomers), xylene diisocyanate (including various isomers), tetramethylxylene diisocyanate (including various isomers), phenylene diisocyanate Aromatic diisocyanates (including various isomers), tetramethylene diisocyanate, 3-methyl-1,5-pentane diisocyanate, aliphatic diisocyanates such as lysine diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, And alicyclic diisocyanates such as hydrogenated diphenylmethane diisocyanate. In addition, these polymeric materials, urethanized products, ureaated products, allophanated products, biuretized products, carbodiimidized products, uretoniminate products, uretdioneized products, isocyanurated products, and the like, and a mixture of two or more of these may be mentioned.

  The isocyanate content of the curing agent (B) thus obtained is preferably 10 to 25% by mass, particularly preferably 13 to 22% by mass. When the isocyanate content is too high, there is a problem in workability such as odor because the free isocyanate content is large. Moreover, since the crosslinking density falls when too low, the intensity | strength and durability of the formed surface material for fiber laminated bodies tend to become inadequate.

  In the present invention, additives can be used for the main agent or the curing agent or both. Examples of the additives include plasticizers, fillers, colorants, flame retardants, organic or inorganic fillers, antioxidants, ultraviolet absorbers, plasticizers, pigments / dyes, antibacterial agents / antifungal agents, and the like.

  The synthetic leather or artificial leather of the present invention comprises a surface layer and a fiber fabric layer formed from the above-mentioned surface layer-forming composition for fiber laminates.

  Synthetic leather and artificial leather using the surface layer-forming composition for fiber laminates of the present invention are prepared by applying a liquid containing the above-mentioned main agent (A) and curing agent (B) to a releasable support and performing primary curing. After that, the production method of pasting the fiber fabric and secondarily curing it, and then removing the releasable support, or a liquid containing the above-mentioned main agent (A) and curing agent (B) was directly applied to the fiber fabric. Thus, it can be obtained by a production method of heat curing.

  In order to form a liquid (hereinafter abbreviated as a mixed liquid) in which the above-mentioned main agent (A) and curing agent (B) are blended on a releasable support, a normal coating method such as a knife over roll is used. After the primary curing, the fiber fabric is pasted and secondarily cured, and then the releasable support is removed. Alternatively, the compounded solution may be directly applied to the fiber fabric by, for example, an application method using a knife coater or a comma coater. In the present invention, the fiber laminate and the synthetic leather generally refer to those in which the surface of the surface layer material is used on the surface side of the final product, but in the same manufacturing method, the surface of the surface layer material is used on the back side. Moist waterproof coatings and moisture permeable waterproof materials can be used as well.

  As the releasable support, for example, release paper or polyester film can be used. Moreover, as said fiber fabric, all of natural fiber and a synthetic fiber can be used, for example. As a specific example, cotton, sufu, polyester, nylon, acrylic, and a blend of two or more of these may be used. Examples of the form include woven fabric, knitted fabric, non-woven fabric, and raised fabric. Moreover, the laminated base material which has porous membranes, such as a polyurethane resin, on the single side | surface of a fiber fabric may be sufficient. These fiber fabrics may be treated with water repellency with silicon resin, fluorine resin or the like.

  Examples of the coating method for direct coating include knife coating, wire bar coating, doctor blade coating, reverse roll coating, and calendar coating method. After the coating agent is coated on the synthetic leather surface, it is cured by heating to form a film.

  As for the film thickness of the surface layer material layer for fiber laminated bodies, 1-200 micrometers is preferable as resin solid content, More preferably, it is 5-100 micrometers.

  Under the present circumstances, the compounding liquid which mix | blended the above-mentioned main ingredient (A) and the hardening | curing agent (B) with the molar ratio of a hydroxyl group and an isocyanate group in the ratio of hydroxyl group / isocyanate group = 90 / 100-110 / 100 was mixed with the fiber fabric. It is preferable to apply to a releasable support or to a fiber fabric and then cure by heating. When the molar ratio of the hydroxyl group to the isocyanate group deviates from this ratio, the strength and durability of the coating layer tends to be insufficient.

  The heating temperature during curing is preferably 50 to 150 ° C. The heating time is preferably 2 minutes to 2 hours. If the temperature is too low or the time is too short, curing will be insufficient. On the other hand, if the temperature is too high or the time is too long, an unnecessary heat history is applied to the coating or the substrate.

  In blending the main agent (A) / curing agent (B), a catalyst can be added for the purpose of shortening the curing step and improving the reaction rate. The catalyst is a tertiary amine catalyst such as triethylamine, tetramethylpropylenediamine, tetramethylhexamethylenediamine or tolylenediamine as a urethanization reaction catalyst, or stannous octoate, stannous oleate, dibutyltin dilaurate or the like. Metal catalysts typified by tin-based catalysts can be mentioned, and these are used alone or in combination.

  Synthetic leather and artificial leather produced using the surface layer-forming composition for fiber laminates of the present invention are useful for clothing, shoes, bags, bags and the like. The surface layer-forming composition for fiber laminates of the present invention can also be used as a coating agent for moisture-permeable and waterproof clothing.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in more detail, this invention is not limited to these. In Examples and Comparative Examples, “%” indicates “mass%”.

[Production of modified polyisocyanate of HDI]
Production Example 1
A volume of 1 L reactor equipped with a stirrer, a thermometer, a cooler, and a nitrogen gas introduction tube was charged with 950 g of HDI and 50 g of isopropanol, and subjected to urethanization reaction at 90 ° C. for 2 hours. When the reaction product was analyzed by FT-IR, the hydroxyl group had disappeared. Next, 0.2 g of zirconium 2-ethylhexanoate was charged and reacted at 90 ° C. for 3 hours. When the reaction product was analyzed by FT-IR and ¹³ C-NMR, the urethane group had disappeared. Next, 0.1 g of phosphoric acid was added and a stop reaction was performed at 50 ° C. for 1 hour. The isocyanate content of the reaction product after the termination reaction was 42.1%. The reaction product was subjected to thin-film distillation at 130 ° C. and 0.04 kPa to remove free HDI, the isocyanate content was 19.4%, the viscosity at 25 ° C. was 100 mPa · s, and the free HDI content was 0.1. Polyisocyanate P-1 having 1% and a color number of 10 APHA was obtained. When P-1 was analyzed by FT-IR and ¹³ C-NMR, the presence of urethane group was not recognized, and the presence of allophanate group was confirmed. Further, traces of uretdione groups and isocyanurate groups were observed. The number average molecular weight of P-1 was determined to be 433, and the average number of functional groups calculated from the number average molecular weight and the isocyanate content was 2.0.

Production Example 2
Capacity with stirrer, thermometer, cooler and nitrogen gas inlet tube: 1 L reactor, 600 parts HDI, 5 parts 1,3-butanediol, 0.1 parts potassium caprate as catalyst, promoter As described above, 0.6 parts of phenol was added, the air in the flask was replaced with nitrogen, and the mixture was heated to a reaction temperature of 70 ° C. with stirring, and reacted at the same temperature for 4 hours. After adding 0.2 parts of phosphoric acid as a terminator to the reaction solution and stirring for 1 hour at the reaction temperature, the reaction product was subjected to thin-film distillation at 130 ° C./0.04 kPa to remove free HDI, and isocyanate. A polyisocyanate P-2 having a content of 20.8%, a viscosity at 25 ° C. of 2,500 mPa · s, a free HDI content of 0.3%, and a color number of 20 APHA was obtained. When P-2 was analyzed by FT-IR and ¹³ C-NMR, an isocyanurate group was confirmed, but traces of allophanate groups and uretdione groups were recognized. The number average molecular weight of P-2 was determined to be 747, and the average number of functional groups calculated from the number average molecular weight and the isocyanate content was 3.7.

[Evaluation of coating]
Examples 1-9, Comparative Examples 1-4
In the combinations shown in Tables 1 and 2, the main agent heated and dissolved at 60 ° C. and the curing agent at room temperature were blended so that the isocyanate groups and hydroxyl groups would be equivalent, and the bar coater was made to have a thickness of 100 μm. After being applied to release paper and heated at 60 ° C. for 30 minutes, it was cured by heating at 120 ° C. for 1 hour. The mixing ratio of the main agent and the curing agent is equivalent to the isocyanate group and the hydroxyl group. Then, it left still at room temperature for 24 hours, and various physical-property evaluation was performed after that. The results are shown in Tables 1 and 2.

In Tables 1 and 2, PCD-1000: PCD obtained by reacting diethyl carbonate and 1,6-HD
Number average molecular weight = 1,000
PCD-2000: PCD obtained by reacting diethyl carbonate and 1,6-HD
Number average molecular weight = 2,000
PCD-3000: PCD obtained by reacting diethyl carbonate and 1,6-HD
Number average molecular weight = 3,000

Physical property evaluation test method Tensile physical properties (each modulus, strength at break, elongation at break)
A sample was punched out with a No. 4 dumbbell cutter and measured according to JIS K7311. The tensile speed was 200 mm / min, and the measurement temperature was 23 ° C.
Hysteresis loss Samples were punched out with a No. 4 dumbbell cutter, pulled at 200 mm / min, measurement temperature at 23 ° C. until elongation reached 300%, and then the load was removed for measurement.

  As shown in Tables 1 and 2, the film formed from the surface layer-forming composition for fiber laminates of the present invention was excellent in balance between strength and flexibility. On the other hand, Comparative Examples 1 and 3 were films that lacked flexibility, had low strength, and had no physical properties. In Comparative Examples 2 and 4, the strength was sufficient, but the hysteresis loss was large and the elasticity was lacking. In addition, there was no off-flavor at the time of making all films, and workability was good.

[Manufacture of synthetic leather]
Example 10
Synthetic leather was produced by the following procedure.
1) The combination of Example 3 with the main agent heated and dissolved at 60 ° C. and the curing agent at room temperature, the mixing ratio of isocyanate group and hydroxyl group being equivalent, and dioctyltin dilaurate as the catalyst in the main agent / curing agent mixture In contrast, 300 ppm is added, and the main agent, curing agent and catalyst are mixed uniformly, and degassed under reduced pressure.
2) Next, this mixed solution was applied to a release paper so as to have a thickness of 15 μm, and heated at 120 ° C. for 5 minutes.
3) Thereafter, a polyester taffeta as a base fabric was stacked thereon and pressure-bonded.
4) After aging at 50-60 ° C. for 48 hours, the release paper was peeled off to obtain a synthetic leather.
The obtained synthetic leather was soft and had a good texture. Moreover, there was no off-flavor etc. at the time of production, and it considered the productivity and the environment.

Example 11
Synthetic leather was produced by the following procedure.
1) The combination of Example 3 with the main agent heated and dissolved at 60 ° C. and the curing agent at room temperature, the mixing ratio of isocyanate group and hydroxyl group being equivalent, and dioctyltin dilaurate as the catalyst in the main agent / curing agent mixture In contrast, 300 ppm is added, and the main agent, curing agent and catalyst are mixed uniformly, and degassed under reduced pressure.
2) Next, this compounded solution was applied as a base fabric on a polyester taffeta with a bar coater so as to have a thickness of 15 μm.
3) Heated at 120 ° C. for 5 minutes and then aged at 50-60 ° C. for 48 hours to obtain a synthetic leather.
The obtained synthetic leather was soft and had a good texture. Moreover, there was no off-flavor etc. at the time of production, and it considered the productivity and the environment.

[Manufacture of artificial leather]
Example 12
Artificial leather was produced by the following procedure.
1) The combination of Example 3 with the main agent heated and dissolved at 60 ° C. and the curing agent at room temperature, the mixing ratio of isocyanate group and hydroxyl group being equivalent, and dioctyltin dilaurate as the catalyst in the main agent / curing agent mixture In contrast, 300 ppm is added, and the main agent, curing agent and catalyst are mixed uniformly, and degassed under reduced pressure.
2) Next, this mixed solution was applied to a release paper so as to have a thickness of 15 μm, and heated at 120 ° C. for 5 minutes.
3) Thereafter, a three-dimensional entangled nonwoven fabric made of polyester was stacked thereon and pressure-bonded.
4) After aging at 50-60 ° C. for 48 hours, the release paper was peeled off to obtain artificial leather.
The obtained artificial leather was soft and had a good texture. Moreover, there was no off-flavor etc. at the time of production, and consideration was given to productivity and the environment.

Example 13
Artificial leather was produced by the following procedure.
1) The combination of Example 3 with the main agent heated and dissolved at 60 ° C. and the curing agent at room temperature, the mixing ratio of isocyanate group and hydroxyl group being equivalent, and dioctyltin dilaurate as the catalyst in the main agent / curing agent mixture In contrast, 300 ppm is added, and the main agent, curing agent and catalyst are mixed uniformly, and degassed under reduced pressure.
2) Next, this compounded solution was applied on a three-dimensional entangled nonwoven fabric made of polyester with a bar coater so as to have a thickness of 15 μm.
3) Heated at 120 ° C. for 5 minutes and then aged at 50-60 ° C. for 48 hours to obtain artificial leather.
The obtained artificial leather was soft and had a good texture. Moreover, there was no off-flavor etc. at the time of production, and consideration was given to productivity and the environment.

Claims (7)

  In the surface layer material-forming composition for a fiber laminate composed of the main agent (A) and the curing agent (B), the main agent (A) is a polycarbonate diol obtained from 1,6-hexanediol and a low molecular carbonate, The curing agent (B) is a modified polyisocyanate (B1) of hexamethylene diisocyanate having a number average molecular weight of 350 to 500 and an average functional group number (f) of 2 ≦ f <3, and an isocyanate of hexamethylene diisocyanate having f ≧ 3. It consists of a nurate-modified polyisocyanate (B2), and is (B1) :( B2) = 50: 50 to 95: 5 (mass ratio), and is organic in both the main agent (A) and the curing agent (B). A surface layer material-forming composition for a fiber laminate, which does not contain a solvent.   The surface layer material-forming composition for a fiber laminate according to claim 1, wherein (B1) is an allophanate-modified isocyanate obtained from monool and hexamethylene diisocyanate.   A synthetic leather comprising a surface layer formed from the surface layer material-forming composition for a fiber laminate according to claim 1 or 2, and a fiber fabric layer.   An artificial leather comprising a surface layer formed from the surface layer material-forming composition for fiber laminate according to claim 1 or 2, and a fiber fabric layer.   A liquid containing the main agent (A) and the curing agent (B) according to claim 1 or 2 is applied to a releasable support, subjected to primary curing, and then secondarily cured by bonding to a fiber fabric, and then releasable support. A method for producing synthetic leather or artificial leather, wherein the body is removed.   A method for producing synthetic leather or artificial leather, wherein a liquid containing the main agent (A) and the curing agent (B) according to claim 1 or 2 is directly applied to a fiber fabric and cured by heating. In the liquid which mix | blended the main ingredient (A) of Claim 1 or 2, and the hardening | curing agent (B), the molar ratio of the hydroxyl group of the said compounding liquid and an isocyanate group is hydroxyl group / isocyanate group = 90 / 100-110 / 100. It is set as a ratio, The manufacturing method of the synthetic leather or artificial leather of Claim 5 or 6 characterized by the above-mentioned.