JP4221956B2 - Napped leather-like sheet-like material and method for producing the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a napped leather-like sheet-like material having a soft texture and high strength and durability, and a method for producing the same, and in particular, a napped leather-like sheet-like material capable of exhibiting good characteristics in a thin field and a method for producing the same. It is about.
[0002]
[Prior art]
Napped leather-like sheet-like material obtained by impregnating a polymer-like material with a synthetic fiber sheet has uniformity, dyeing fastness, and texture flexibility not found in natural leather. Its use has spread to furniture and sheet applications. In particular, napped leather-like sheet-like materials mainly composed of ultrafine fibers having a fineness of 0.5 dtex or less and polyurethane are excellent in quality, surface touch and texture, and are widely used not only for clothing but also for chair upholstery and car seats. .
[0003]
However, such leather-like sheet-like materials, when used for a long period of time, have problems such as partly long hairs, tangling, or the appearance of hairballs changing or tearing. There is a point.
[0004]
One of the causes of such a problem is deterioration of the polyurethane, and several attempts have been made to solve the problem of deterioration of the polyurethane by using a highly durable polyurethane.
[0005]
For example, regarding the hydrolysis resistance, it has been studied to use a polyurethane using a polyether diol (hereinafter referred to as a polyether polyurethane). Although the polyurethane is excellent in hydrolysis resistance, the light resistance is poor. There is a problem.
[0006]
Polyurethanes using polyester diols (hereinafter referred to as polyester-based polyurethanes) are excellent in light resistance but have a problem of poor hydrolysis resistance.
[0007]
Polyurethane using polycarbonate diol (hereinafter referred to as polycarbonate-based polyurethane) has relatively good light resistance and hydrolysis resistance, but is physically hard and difficult to produce as a product with a soft texture. There was a problem.
[0008]
In addition, even if attempts are made to soften by reducing the amount of polyurethane attached to the sheet, deterioration of the polyurethane is inevitable if used for a long period of time. As a result, sufficient durability cannot be obtained.
[0009]
In particular, when trying to obtain a flexible leather-like sheet suitable for light clothing, it becomes more difficult to balance such flexibility and durability, and those that substantially satisfy them can be obtained. The actual situation is not.
[0010]
As described above, the conventional technological idea of simply improving the durability of polyurethane, as in the past, is a napped leather-like sheet that is excellent in flexibility, strength, and durability, especially in thin areas. It was not possible to obtain a napped-leather-like sheet-like material excellent in all of the above properties.
[0011]
[Problems to be solved by the invention]
An object of the present invention is to provide a napped leather-like sheet-like material having a soft texture, high strength and durability, and a method for producing the same, in order to solve the above-mentioned drawbacks of the prior art.
[0012]
[Means for Solving the Problems]
The present invention achieves the object by the following means.
[0013]
  That is, the napped leather-like sheet-like material of the present invention is made of a polycarbonate-based polyurethane in which an ultrafine fiber nonwoven fabric of 0.5 dtex or less and a diol-corresponding component constituting polyurethane contain a polycarbonate diol portion of 30% by weight to 90% by weight. In the napped leather-like sheet material, (1) a step of joining two or more primary fiber entangled non-woven fabrics made of ultrafine fibers or ultrafine fiber generating fibers, and (2) a binder to the joined nonwoven fabric As a manufacturing method, including a step of applying a polycarbonate-based polyurethane, and (3) a step of subsequently slicing the nonwoven fabric into two pieces in the thickness direction.TheNapped leather-like sheet-like material characterized by.
[0014]
Further, in the above-mentioned napped-toned leather-like sheet-like material of the present invention, preferably, the napped-toned leather-like sheet-like material has a tear resistance after forced deterioration treatment of 70 times or more. It is a shape.
[0015]
Alternatively, in the above-mentioned napped leather-like sheet-like material of the present invention, preferably, the polyurethane contains 30% by weight or more and 90% by weight or less of a polycarbonate diol part as a diol-equivalent component constituting the polyurethane, and the remaining part is the following: It is a napped leather-like sheet-like material that is selected from the group.
[0016]
Group: Polyneopetyl adipate diol, polycaprolactone diol, poly 2,5-diethylpentane adipate, polytetramethylene ether glycol, polytetramethylene glycol.
[0017]
Moreover, these leather-like sheet-like materials can be manufactured by the following method for manufacturing a nap-finished leather-like sheet of the present invention.
[0018]
That is, the method for producing a napped-toned leather-like sheet-like material of the present invention comprises the steps of (1) ultrafine-fiber or non-fine fiber-like sheet-like product comprising an ultrafine fiber nonwoven fabric of 0.5 dtex or less and polycarbonate polyurethane. A step of joining two or more primary fiber entangled nonwoven fabrics made of ultrafine fiber-generating fibers, (2) a step of applying polycarbonate polyurethane as a binder to the joined nonwoven fabrics, and (3) the nonwoven fabrics thereafter And a step of slicing into two pieces in the thickness direction.
[0019]
In the method of the present invention, preferably, the polycarbonate-based polyurethane used is composed of a polycarbonate-based polyurethane in which the diol-corresponding component constituting the polyurethane includes a polycarbonate diol portion of 30% by weight to 90% by weight. It is the manufacturing method of the leather-like sheet-like material of the present invention as described above.
[0020]
Alternatively, or preferably, the nonwoven fabric is impregnated with a polyurethane solution and then immersed in an aqueous solution containing a cationic surfactant to wet-solidify the polyurethane, whereby the leather-like sheet according to the present invention is produced. Is the method.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in further detail below.
[0022]
The napped-toned leather-like sheet-like material according to the present invention is a napped-toned leather-like sheet-like material comprising an ultrafine fiber nonwoven fabric of 0.5 dtex or less and polyurethane, and is subjected to a forced deterioration treatment according to the regulations described later in the text. Before and after the above, the tear resistance retention rate according to the rules described later in the text is 50% or more.
[0023]
That is, the raised leather-like sheet-like product of the present invention is characterized in that the tear resistance retention is 50% or more, preferably 70% or more, and most preferably 80% or more.
[0024]
In the present invention, the forced deterioration treatment means that the leather-like sheet-like material is left for 5 weeks in a constant temperature and constant temperature humidity chamber adjusted to a temperature of 70 ° C. and a relative humidity of 95%.
[0025]
Further, the tear resistance of the present invention is measured as follows.
[0026]
First, an apparatus as shown in FIG. 1 is used for the measurement.
[0027]
Reference numeral 1 denotes a sheet-like object. Reference numeral 2 denotes a rotating roll, which is electrically rotated counterclockwise when viewed from the front side in the state of FIG. The diameter is 30 mm. Reference numeral 3 denotes a claw-like component having a shape as shown in FIG. The claw-like part has a thickness of 1 mm, a radius of curvature of the tip portion of 7.5 mm, and a material of SUS (stainless steel) 304. Reference numeral 4 denotes a guide roll, which is a free roll that rotates with little resistance.
[0028]
Using such an apparatus, the tear resistance is measured by the following procedure. Hereinafter, with reference to FIG. 2, a sample to be evaluated is cut into a width of 10 cm and a length of 50 cm, and one end in the length direction is fixed to the sheet press 1. Next, a weight 7 having a weight of 800 g is attached to the unfixed end of the sample to be evaluated, and is lowered through the upper side of the guide roll 4.
[0029]
The relative positional relationship of each part is as follows. The distance between the guide roll and the sheet press (A in FIG. 2) is 290 mm, the horizontal distance (B in FIG. 2) between the sheet press and the central axis of the rotating roll is 140 mm, and the distance in the height direction (FIG. C) in 2 is 35 mm.
[0030]
In this way, with a certain tension applied to the artificial leather, the tip of the nail-shaped part is rubbed against the surface of the leather-like sheet, and the rotating roll is rotated at a speed of 1 rotation / second, The number of times until the artificial leather is torn is regarded as tear resistance. In the case where the leather-like sheet is a structure in which a woven or knitted fabric (hereinafter referred to as woven / knitted fabric) and a nonwoven fabric are intertwined and / or a structure in which woven / knitted fabric is bonded to at least one surface, When the surface is shaved and the woven / knitted fabric is exposed, it is determined that the material has been torn.
[0031]
Further, when the resistance to breakage of the sample before and after forced deterioration is Rb and Ra, respectively, Ra / Rb × 100 is defined as the resistance to breakage.
[0032]
Conventionally, as a method for evaluating the durability of a leather-like sheet made of fiber and polyurethane, generally, the breaking strength, the surface abrasion resistance, and the molecular weight measurement of polyurethane have been used. However, in actual use, changes in the entanglement state of the fibers and deterioration of the polyurethane are related in a complicated manner, and even if it is a good value in such an evaluation method, when actually used, In some cases, pills are generated on the surface in a shorter period of time than expected, or the raised hairs are extremely long, or they are torn if they are severe.
[0033]
The present inventors considered the cause of deterioration in actual use, and arrived at a conclusion that a means combining the resistance to breakage and forced deterioration treatment as in the present invention as a means for evaluating long-term durability was valid, It has been found that if such properties are satisfied, a napped leather-like sheet-like material can be obtained which does not generate or tear even if used for a long time.
[0034]
In other words, the napped leather-like sheet-like material having excellent strength, durability and flexibility may be a polyurethane having high strength and hardly undergoing degradation such as hydrolysis. In reality, the improvement cannot be achieved by improvement only from the polyurethane surface.
[0035]
As a result of intensive studies, the present invention has obtained the knowledge that the intended purpose can be achieved only by using a nonwoven fabric excellent in durability by a special manufacturing method and combining this with a special polyurethane.
[0036]
The napped leather-like sheet-like product of the present invention is premised on ultrafine fibers. The fineness of the ultrafine fiber is required to be 0.5 dtex or less from the viewpoint of flexibility and quality, but in the case of polyester fiber, it is 0.005 to 0. In the case of polyamide fibers, those in the range of 0.001 to 0.1 dtex are preferable. Particularly, polyester ultrafine fibers having a fineness of 0.01 to 0.3 dtex are preferable in terms of durability. More preferred.
[0037]
In addition, as long as the effect of the present invention is not impaired, the above-described ultrafine fibers can be mixed and used, or fibers thicker than 0.5 dtex are mixed within a range where the effect of the present invention is not impaired. It doesn't matter. In addition, the cross-sectional shape of the ultrafine fiber may be a normal round cross section, or a triangular or cross-shaped cross section. The material of the ultrafine fiber used here is not particularly limited, and is conventionally represented by polyesters typified by polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, nylon 6, nylon 6, 6 and the like. Polyamide or the like can be used.
[0038]
As a method for obtaining such ultrafine fibers, a method for directly obtaining the desired ultrafine fibers, and once creating a thick multicomponent fiber (hereinafter referred to as ultrafine fiber-generating fiber), then treating the fibers to express the ultrafine fibers. There is a method to squeeze. In the latter case, the fiber form is a side-by-side type composite fiber in a state where the polymers are bonded to each other, a sea-island type composite fiber in which another polymer exists in an island shape, or a polymer mixed in an alloy shape. A blend type fiber or a combination thereof can be preferably used. In order to generate ultrafine fibers from such fibers, one component of these components is removed or different components are separated.
[0039]
When forming ultrafine fibers by removing at least one kind of polymer from such ultrafine fiber-generating fibers, the types of polymers to be removed include polyolefins such as polyethylene and polystyrene, and copolymers of sodium sulfoisophthalic acid and polyethylene glycol. Thus, it is possible to use a copolyester having enhanced alkali solubility, but the present invention is not limited to these, and any of those that achieve the present invention can be used.
[0040]
In addition, there is no particular limitation on the method for separating the polymers from each other by physical or chemical means. At least one kind of component is shrunk by a method of physically kneading or beating the ultrafine fiber generating fiber or by heat and / or chemicals. Alternatively, a swelling method or the like can be employed.
[0041]
The typical production method for obtaining the napped leather-like sheet-like material of the present invention is then joined in the state where (1) two or more primary fiber entangled nonwoven fabrics composed of ultrafine fibers or ultrafine fiber-generating fibers are stacked. A step, (2) a step of imparting polycarbonate polyurethane as a binder to the bonded nonwoven fabric, and (3) a step of subsequently slicing the nonwoven fabric into two in the thickness direction.
[0042]
Hereinafter, this method will be described more specifically.
[0043]
As a method for forming the primary fiber entangled nonwoven fabric, a web is formed by using ultrafine fiber generating fibers and appropriately adopting a method using a card, a cross wrapper, a random web or a paper making method. The web thus obtained is entangled with fibers by a fiber entanglement means such as a needle punch or a water jet punch to form a primary fiber entangled nonwoven fabric. Next, at least two sheets of the primary fiber entangled nonwoven fabric are stacked and bonded.
[0044]
A point to be noted in the present invention is to balance the fiber entanglement degree of the primary fiber entangled nonwoven fabric with the bonding force at the time of bonding. A higher entanglement degree of the primary fiber entangled nonwoven fabric is preferable because the final product quality is improved and the strength is increased.
[0045]
However, if this entanglement is increased too much, the movement of fibers in the nonwoven fabric is limited when the nonwoven fabric is lap-joined, and sufficient bonding between the nonwoven fabrics cannot be obtained. For this reason, peeling may occur between the nonwoven fabric layers during a processing step performed after the bonded nonwoven fabric is impregnated with polyurethane, which may cause a serious problem. On the other hand, if the entanglement of the nonwoven fabric is too low, the bonding strength of the nonwoven fabric can be increased, but the quality of the final product is lowered and the meaning of joining the two nonwoven fabrics is lost.
[0046]
Therefore, at this time, the nonwoven fabric to be used should be selected in consideration of these comprehensive balances. Moreover, it is preferable to integrate the primary fiber entangled nonwoven fabric or other woven fabric, knitted fabric, or nonwoven fabric at the time of joining in order to moderately suppress the elongation during processing of the sheet-like material. In joining the primary fiber entangled nonwoven fabric, two or more of the nonwoven fabrics are overlapped and then joined by a water jet punch or needle punch means. If this joint is too strong, the strength drop after slicing is large, and if it is too weak, the nonwoven fabric peels off during the processing process, making it impossible to process, so the joining conditions are needles with reference to the properties of the nonwoven fabric, such as density and basis weight. In the case of a punch, it is effective to appropriately adjust the shape of the needle, the number of punches, the depth of the punch, etc., and in the case of a water jet punch, the shape, size, water flow pressure, etc. of the water flow injection hole are appropriately adjusted. It is necessary to make the degree of joining appropriate by such means.
[0047]
In addition, although the case where two nonwoven fabrics were joined here was shown here, a better result may be obtained even if the number of joined sheets is increased, and the present invention does not exclude such means.
[0048]
When the bonded nonwoven fabric thus obtained is used as in the present invention, after the thin nonwoven fabric is formed, the fibers that are vertically oriented in the nonwoven fabric remain mostly in each thin nonwoven fabric in order to bond them. There are very few fibers that straddle the orientation. For this reason, even if the vicinity of the layer between the nonwoven fabrics is sliced, the cut of the vertically oriented fibers hardly occurs, and the strength of the product can be improved without causing an extreme decrease in the fiber length due to the slicing as in the conventional structure nonwoven fabric. However, the present invention is not achieved simply by using a nonwoven fabric having such a structure. That is, when this nonwoven fabric is used, a product having good initial characteristics can be obtained, but a product having sufficient durability cannot be obtained. Therefore, in order to obtain a product having the intended and sufficient durability, which is the object of the present invention, a combination of a nonwoven fabric having such a special structure and the following special polyurethane is necessary.
[0049]
The polyurethane used in the present invention is characterized by using a polycarbonate diol containing 30% by weight or more and 90% by weight or less, preferably 50% by weight or more and 90% by weight or less as a polymer diol used for polyurethane formation. . If the polycarbonate diol is less than 30% by weight, the durability is insufficient, which is not preferable, and if it exceeds 90% by weight, the flexibility is not preferable.
[0050]
The polycarbonate diol as referred to in the present invention is one in which diol skeletons are linked via a carbonate bond to form a polymer chain and have hydroxyl groups at both ends. The diol skeleton is determined by the glycol used as a raw material, but the type thereof is not particularly limited. For example, 1,6-hexanediol, 1,5-pentanediol, neopentyl glycol, 3-methyl- 1,5-pentanediol can be used.
[0051]
Further, a copolymer polycarbonate diol using at least two or more kinds of glycols selected from these glycol groups as raw materials is preferable because a leather-like sheet having excellent flexibility and appearance can be obtained. In order to obtain a leather-like sheet having particularly excellent flexibility, other chemical bonds such as esters and ethers can be introduced into the polycarbonate diol or copolymer polycarbonate diol. As a method for introducing this bond, a compound having an ether bond or an ester bond is mixed when the polycarbonate diol is polymerized and copolymerized, or after the polycarbonate diol and other polymer diols are individually polymerized, they are mixed. Thus, a method used for polymerization of polyurethane can be employed.
[0052]
The polymer diol mixed with the polycarbonate diol is one or more selected from the group consisting of polytetramethylene ether glycol, polyneopentyl adipate diol, polycaprolactone diol, and poly 2,5-diethylpentane adipate. And durability are preferable.
[0053]
The molecular weight of these polymer diols is not particularly limited, and can be appropriately selected according to the characteristics of the target leather-like sheet. However, when the molecular weight is less than 500, the physical properties are improved but the texture is improved. When it becomes harder and larger than 3000, the texture becomes soft but the physical properties tend to decrease.
[0054]
The method for producing the polyurethane in the present invention is not particularly limited. As in a conventional method, first, a method in which a polymer diol and a diisocyanate are reacted to form a prepolymer and then reacted with a chain extender is used. It is also possible to use a method in which all raw materials are mixed and reacted at the same time.
[0055]
The ratio of the polymer diol and the diisocyanate at this time is not particularly limited, and when the importance is attached to the flexibility, the polymer diol is increased, and when the durability is emphasized, the diisocyanate is increased. The reaction conditions are preferably adjusted so that the molar ratio is 1: 1.5 to 1: 5.
[0056]
When using a plurality of polymer diols and diisocyanates, they may be reacted separately to prepare a plurality of prepolymers in advance and then mixed and reacted with a chain extender to form a structure close to that of a block copolymer. A prepolymer may be prepared using a mixture of diols and reacted with a chain extender to form a structure close to a random copolymer. Furthermore, an organotin compound, an organotitanium compound, a tertiary amine, or the like can be added as a reaction catalyst.
[0057]
The diisocyanate combined with such a polymer diol is not particularly limited. For example, when importance is attached to heat resistance, aromatic diisocyanates such as 4,4′-diphenylmethane diisocyanate can be used, and NOx and When it is desired to suppress yellowing due to light, alicyclic diisocyanates such as isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, 1,6-hexamethylene diisocyanate, and aliphatic diisocyanates can be used. Further, a plurality of these diisocyanates can be used in combination depending on the purpose.
[0058]
Further, the chain extender to be reacted with the polymer diol and diisocyanate is not particularly limited, and a low molecular compound having two or more active hydrogens can be used. For example, ethylene glycol, propylene glycol, 1,6- Use of aliphatic diols such as hexane diol, polyalkylene glycols such as diethylene glycol and dipropylene glycol, aliphatic diamines such as ethylene diamine and isophorone diamine, or aromatic diamines such as alicyclic diamine and methylene bisaniline can do.
[0059]
In particular, when 4,4'-diphenylmethane diisocyanate is used as the diisocyanate and an aliphatic diol having 2 to 8 carbon atoms, particularly ethylene glycol, is used as the chain extender, a polyurethane having outstanding durability and flexibility can be obtained. It is preferable because it is possible.
[0060]
Adding other solvents and water to the polyurethane thus obtained within a range that does not interfere with the solubility of the polyurethane, and adding a coagulation regulator such as a higher alcohol or a surfactant for the purpose of adjusting the coagulation structure of the polyurethane. You can also. Furthermore, a pigment, an ultraviolet absorber and an antioxidant can be added as necessary. By combining such means, the intended effect is further amplified.
[0061]
In the present invention, the polyurethane thus obtained is solidified after impregnating the bonded nonwoven fabric with the bonded nonwoven fabric. In general, after impregnating a nonwoven fabric with a polyurethane solution dissolved in a solvent such as dimethyl sulfoxide, dimethylformamide, or dimethylacetamide, which is a hydrophilic solvent, the polyurethane is solidified by dipping in water or an organic solvent aqueous solution. preferable. However, the polyurethane may be emulsified and impregnated and then solidified.
[0062]
When impregnated with polyurethane, it is necessary to adjust the amount of polyurethane applied according to the flexibility and durability of the target leather-like sheet, and it is difficult to determine it uniformly. It is 65% by weight or less and more preferably 25% or more and 55% or less. If it is less than 15% by weight, even if the initial physical properties are good, the quality and physical properties may deteriorate due to long-term use, which may not be preferable. On the other hand, when the polyurethane content exceeds 65%, not only the texture becomes hard and the core is formed, but also the napping property in the napping process is lowered, and the polyurethane remains in a fluffy state between the nappings. When viewed from the (surface), it may be unsightly and the quality may be reduced.
[0063]
In the present invention, two sheets are obtained by horizontally slicing the sheet after application of polyurethane horizontally at substantially the center in the thickness direction. Then, each sheet is subjected to napping formation processing. The napping method is not particularly limited as long as the intended leather-like appearance can be obtained, and known napping and grinding processes can be employed. In particular, it is preferable to employ a grinding treatment because good quality can be easily obtained by removing polyurethane from the surface of the sheet-like material while adjusting the napped length. In such a grinding process, while rotating an abrasive having abrasive grains on the surface, a fiber sheet-like material containing polyurethane is pressed to remove the polyurethane from the surface of the fiber sheet-like material, and at the same time, the fibers are cut to an appropriate length to raise the fibers. Form. As such an abrasive, sandpaper or a roll having abrasive grains on the surface can be used. Such grinding processing can be repeated a plurality of times as necessary. Sheets after napping are dyed and finished as necessary to make the desired product. The dyeing / finishing method is not particularly limited, and a conventionally known method can be employed.
[0064]
In addition, although demonstrated about the representative example until now, in this invention, the order of polyurethane provision and napping formation processing can be suitably selected according to the kind of sheet-like thing.
[0065]
For example, it is difficult to form napping such as woven fabric. First, nap is formed, then polyvinyl alcohol is applied, and further polyurethane is applied. This is a preferable means for obtaining good napping.
[0066]
【Example】
Hereinafter, the present invention will be specifically described using examples.
[0067]
The mixing ratios used in the examples are all weight ratios unless otherwise specified.
[0068]
The meanings of the abbreviations used in the examples are as follows.
[0069]
EG: Ethylene glycol
DMF: N, N'-dimethylformamide
MDI: 4,4'-diphenylmethane diisocyanate
PCL: polycaprolactone diol
PHC: Polyhexamethylene carbonate diol
PTMG: Polytetramethylene ether glycol
Moreover, the evaluation method in an Example is as follows.
(1) Break resistance test:
It was measured by the method described in the specification.
(2) Forced deterioration processing:
It processed by the method described in the specification using the constant temperature and humidity chamber (EY-101 by Tabai Espec Co., Ltd.).
Example 1
As a polymer diol, a 50:50 mixture of PHC having a molecular weight of 2000 and PTMG having a molecular weight of 2000, MDI as a diisocyanate, EG as a chain extender, and obtaining a polyurethane by a conventional method so that the solid content becomes 12% by weight. A polyurethane impregnating solution was prepared by diluting with DMF and adding 1.5% by weight of a benzophenone ultraviolet absorber as an additive.
[0070]
Separately, a sea-island composite fiber was prepared using a sea-island type composite yarn base. The composite conditions are as follows.
[0071]
Sea ingredient: Polystyrene
Island component: Polyethylene terephthalate
Sea-island ratio: 30% sea, 70% island
The sea-island composite fiber was stretched 3.1 times, further crimped, and then cut to obtain raw cotton. The raw cotton is made into a web using a cross wrapper, and the punch density is 2000 / cm.²With a needle punch, with a basis weight of 250 g / m²A short fiber nonwoven fabric was obtained. An additional 300 / cm with the two short fiber nonwoven fabrics stacked²Bonding at a punch density of
[0072]
The nonwoven fabric was impregnated with a 10% aqueous solution of polyvinyl alcohol, and then squeezed and dried. Then, the sea component was extracted with trichlorethylene to obtain a fiber sheet-like product composed of ultrafine fibers of 0.08 dtex.
[0073]
The fiber sheet was immersed in the above polyurethane impregnating solution, and the amount of the polyurethane impregnating solution applied was adjusted with a squeeze roll, and then the polyurethane was coagulated in an aqueous DMF solution. After that, after removing DMF and polyvinyl alcohol with hot water at 85 ° C and drying, slice the sheet into two in the thickness direction, buff the surface, and further dye with disperse dye to make leather-like A sheet was obtained.
[0074]
The obtained sheet-like material has a soft texture, and the tear resistance is 132 times before the forced deterioration treatment and 108 times after the forced deterioration treatment, and the resistance to breakage after the forced deterioration treatment is 82%. Met.
Comparative Example 1
250 g / m²300 short fiber nonwoven fabric / cm²Instead of the non-woven fabric obtained by joining at a punch density of 2, the non-woven fabric was joined by the same method as in Example 1 and the punch density was 2300 / cm from the beginning.², Basis weight 500g / m²A leather-like sheet was produced in the same manner as in Example 1 except that a non-woven fabric was produced.
[0075]
Although the obtained sheet-like material has a soft texture, the tear resistance is 115 times before the forced deterioration treatment and 48 times after the forced deterioration treatment, and the tear resistance retention rate after the forced deterioration treatment Was 42%.
Example 2
In producing polyurethane, a leather-like sheet-like material was obtained in the same manner as in Example 1 except that an 80:20 mixture of PHC having a molecular weight of 2000 and PCL having a molecular weight of 2000 was used as the polymer diol.
[0076]
The obtained sheet-like material has a soft texture, and the tear resistance is 152 times before the forced deterioration treatment and 133 times after the forced deterioration treatment, and the resistance to breakage after the forced deterioration treatment is 88%. Met.
Comparative Example 2
In producing polyurethane, a leather-like sheet was obtained in the same manner as in Example 1 except that PCL having a molecular weight of 2000 was used as the polymer diol.
[0077]
Although the obtained sheet-like material has a soft texture, the tear resistance is 140 times before the forced deterioration treatment and 49 times after the forced deterioration treatment after the forced deterioration treatment. Was 35%.
Comparative Example 3
In producing polyurethane, a leather-like sheet was obtained in the same manner as in Example 1 except that PHC having a molecular weight of 2000 was used alone as the polymer diol.
[0078]
The obtained sheet-like material had a tear resistance of 171 times before the forced deterioration treatment and 160 times after the forced deterioration treatment. The tear resistance retention after the forced deterioration treatment was 94%, but it was extremely hard. The texture was unsuitable for practical use.
Comparative Example 4
In producing polyurethane, a leather-like sheet was obtained in the same manner as in Example 1 except that a 20:80 mixture of PHC having a molecular weight of 2000 and PTMG having a molecular weight of 2000 was used as the polymer diol.
[0079]
The obtained sheet-like material has a soft texture, and the tear resistance is 93 times before the forced deterioration treatment and 37 times after the forced deterioration treatment, and the resistance to tearing after the forced deterioration treatment is 40%. Met.
[0080]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the napkin leather-like sheet-like material which has a soft texture, high strength, and durability, and is suitable for a thin ground use especially, and its manufacturing method are provided.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining a tear resistance test method and is a schematic perspective view of the test apparatus;
FIG. 2 is a diagram for explaining a tear resistance test method, and is a side view of the test apparatus;
FIG. 3 is a schematic view showing a claw-like component used in an apparatus for performing a tear resistance test.
[Explanation of symbols]
1: Press down the sheet
2: Rotating roll
3: Claw-shaped parts
4: Guide roll
5: Mount
6: Leather-like sheet
7: Weight of 800g

Claims (6)

In a napped leather-like sheet-like material comprising an ultrafine fiber nonwoven fabric of 0.5 dtex or less and a polycarbonate-based polyurethane in which the diol-equivalent component constituting the polyurethane contains a polycarbonate diol portion of 30% by weight or more and 90% by weight or less, (1) A step of joining two or more primary fiber entangled nonwoven fabrics made of ultrafine fibers or ultrafine fiber-generating fibers, (2) a step of imparting polycarbonate polyurethane as a binder to the joined nonwoven fabrics, (3) nonwoven fabric then sliced into two in the thickness direction process, which is produced by a production method including a napped leather-like sheet according to claim.   Furthermore, the breaking resistance after a forced deterioration process is 70 times or more, The napped-toned leather-like sheet-like material of Claim 1 characterized by the above-mentioned. Polyurethane, diol equivalent component constituting the polyurethane comprises a polycarbonate diol portion 30 wt% to 90 wt% or less, 請 Motomeko 1 or you wherein the remaining portion is one selected from the following group 2. Napped leather-like sheet-like material according to 2.
Group: Polyneopetyl adipate diol, polycaprolactone diol, poly 2,5-diethylpentane adipate, polytetramethylene ether glycol.   When creating a napped leather-like sheet-like material made of ultrafine fiber nonwoven fabric of 0.5 dtex or less and polycarbonate-based polyurethane, (1) stack two or more primary fiber entangled nonwoven fabrics made of ultrafine fibers or ultrafine fiber-generating fibers And (2) a step of applying polycarbonate polyurethane as a binder to the bonded nonwoven fabric, and (3) a step of subsequently slicing the nonwoven fabric into two in the thickness direction. A method for producing a leather-like sheet.   5. The leather-like sheet-like product according to claim 4, wherein the polycarbonate-based polyurethane used is a polycarbonate-based polyurethane in which the diol-corresponding component constituting the polyurethane contains a polycarbonate diol portion of 30% by weight to 90% by weight. Method.   6. The method for producing a leather-like sheet according to claim 4, wherein the nonwoven fabric is impregnated with a polyurethane solution and then immersed in an aqueous solution containing a cationic surfactant to wet-solidify the polyurethane.

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