KR101956332B1 - An additive slurry for the production of polyurethane-urea elastic fibers - Google Patents

Abstract

The additive slurry for producing a polyurethane-urea elastic fiber according to the present invention includes a solvent, a functional additive, and a moisture removing agent. According to the additive slurry for producing a polyurethane-urea elastic fiber according to the present invention, a moisture removing agent is added and mixed so as to remove moisture that may be mixed in the additive slurry, so that moisture is not penetrated into the spinning solution due to the additive slurry Thereby preventing the gel from being generated in the spinning solution and preventing the degradation of the quality of the polyurethane-urea elastic fiber due to moisture.

Description

[0001] The present invention relates to an additive slurry for polyurethane-urea elastic fibers,

The present invention relates to an additive slurry for producing polyurethane-urea elastic fibers, and more particularly, to an additive slurry for producing polyurethane-urea elastic fibers with reduced water content.

The polyurethane-urea elastic fiber is produced by stretching a prepolymer of an isocyanate-terminated prepolymer synthesized with a high molecular weight polyol and an excess of an organic diisocyanate with a diamine, mainly by dry and melt spinning to obtain a polyamide fiber or poly It is used as elastic material for various kinds of clothing such as foundation, sock, pantyhose, and swimwear, and is knitted with ester fiber and natural fiber.

The polyurethane-urea elastic fiber is easily oxidized by heat, ultraviolet rays, chlorine water, combustion gas, etc., and the physical properties are deteriorated, and the appearance becomes poor due to yellowing. Functional additives such as antioxidants, inorganic pigments, antimicrobial agents, antistatic agents, stabilizers and antiseptics are used to compensate for the poor physical properties of the polyurethane-urea elastic fibers. The polyurethane urea elastic fiber polymer polymer solution and the additive slurry using the functional additive are mixed to form a spinning solution, and the spinning solution is spinned and fiberized through the DMAc extraction process.

Among the functional additives for compensating poor physical properties of polyurethane-urea elastic fibers, there are dimethyl acetamide (DMAc), dimethylformamide (DMF), N-methyl-2-pyrrolidone (NMP) and the like.

Insoluble particulates may then be used as the functional additive and may be added to the spinning solution in the form of a mixture such as an additive slurry. The insoluble microparticles are added to the spinning solution as a functional additive by mixing the insoluble microparticles with a solvent, pulverizing and dispersing the insoluble microparticles in a solvent to prepare an additive slurry, and mixing the additive slurry with the polyurethane urea polymer solution to prepare a spinning solution. The additive slurry is pulverized and dispersed to a certain size or less for the purpose of preventing the clogging of the spinneret during the spinning of the insoluble fine particles and for preventing the single yarn of the fibers (breakage of the fibers).

If the time required to make the additive slurry is too long as a result of such a process, there is a possibility that water may be introduced during pulverization and dispersion. In addition, water may be introduced by the free water contained in the functional additive including the insoluble fine particles to be used. When moisture is introduced, as described in Korean Patent No. 10-0368581, since the gel is generated in the polyurethane-urea elastic fiber spinning solution, the physical properties of the elastic fiber and the radiation facilities are adversely affected, The manufacturing cost is increased.

In order to solve this problem, Korean Patent No. 10-0368581 exploits the role of urea by water to inhibit gel formation by adding a small amount of water to the polymerized material, but it has a problem in that it is not easy to control the entire polymerized material , Korean Patent Laid-Open Publication No. 10-1997-0004816 discloses a method in which silica gel, water lubricant, alumina or the like is used as a physical adsorbent to remove water contained in liquid materials for producing a polymer, or calcium chloride, To pass the polymerizate or the material of the polymerizate, but there is a problem that a large-scale apparatus must be provided. Korean Patent Laid-Open No. 10-2001-0033099 discloses that when a salt is added as a functional additive, water contained in a salt is removed by vacuum and warming using a polymeric material and a functional salt except an isocyanate compound in a large-scale apparatus.

The insoluble fine particles as the functional additive contained in the additive slurry deteriorate the uniformity of the additive slurry due to sedimentation of the insoluble fine particles with time, and a dispersant may be added to the additive slurry in order to solve this problem. Useful dispersants as mentioned in the prior art are fatty acids, fatty acid salts, fatty acid esters, aliphatic alcohol dispersants, polyetherphosphates, phosphoric acid ester dispersants, especially those obtained by denaturing and blocking the phosphoric acid esters of Korean Patent No. 10-0658550 Phosphorylated block poly (alkylsiloxane) -poly (alkyleneether) alcohol or aromatic or alkyl aromatic terminal phosphorylated poly (alkylene ether) alcohol, and the like, and various dispersants having other useful properties can be used.

When the functional additive containing insoluble particles is mixed to make the additive slurry and pulverized and dispersed, it takes about 12 to 24 hours and the water is likely to be introduced.

It should be understood that the foregoing description of the background art is merely for the purpose of promoting an understanding of the background of the present invention and is not to be construed as adhering to the prior art already known to those skilled in the art.

SUMMARY OF THE INVENTION The present invention has been conceived to solve such problems, and an object of the present invention is to provide an additive slurry for producing polyurethane-urea elastic fibers having less water inflow.

The additive slurry for producing polyurethane-urea elastic fibers according to an embodiment of the present invention includes a functional additive and a moisture removing agent.

The moisture removing agent may include at least one of potassium thiocyanate, potassium bromide, sodium carbonate, potassium carbonate, sodium nitrate, ammonium nitrate, sodium thiosulfate, calcium oxide, magnesium oxide and isocyanate compounds.

The moisture removing agent may include 1.0 to 35.0 parts by weight based on the total amount of the functional additives contained in the additive slurry.

The isocyanate compound may be at least one of TDI (toluene diisocyanate), MDI (methylene diphenyl diisocyanate) HDI (hexamethylene diisocyanate) IPDI (isophorone diisocyanate) . ≪ / RTI >

According to the additive slurry for producing a polyurethane-urea elastic fiber according to the present invention, a water-removing agent is added and mixed so as to remove water that can be mixed in the additive slurry, so that moisture penetrates into the spinning solution due to the additive slurry Thereby preventing the gel from being generated in the spinning solution and preventing the degradation of the quality of the polyurethane-urea elastic fiber due to moisture.

1 is a process diagram showing a method for producing a polyurethane-urea elastic fiber according to an embodiment of the present invention.
Figure 2 is a simplified representation of the reaction of isocyanate with water.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms as used herein include plural forms as long as the phrases do not expressly express the opposite meaning thereto. Means that a particular feature, region, integer, step, operation, element and / or component is specified, and that other specific features, regions, integers, steps, operations, elements, components, and / And the like.

Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Commonly used predefined terms are further interpreted as having a meaning consistent with the relevant technical literature and the present disclosure, and are not to be construed as ideal or very formal meanings unless defined otherwise.

Hereinafter, an additive slurry for producing a polyurethane-urea elastic fiber according to a preferred embodiment of the present invention and a method for producing a polyurethane elastic fiber using the same will be described with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a process diagram showing a method for producing a polyurethane-urea elastic fiber using an additive slurry for producing polyurethane-urea elastic fibers according to an embodiment of the present invention. FIG.

As used herein, " polyurethaneurea elastic fiber " is a conventional meaning that the fiber-forming material is a synthetic fiber, which is a long-chain synthetic elastomer composed of at least 85% by weight of segmented polyurethaneurea.

To prepare the polyurethane-urea elastic fibers, a spinning solution is prepared by mixing a polyurethane-urea polymer solution and an additive slurry in a suitable spinning solvent, and the spinning solution is discharged into a column of heated gas through a spinneret or into a water bath to remove the solvent do.

Suitable solvents for preparing the polyurethane-urea elastic fibers are generally liquid amides such as dimethylacetamide (DMAc), dimethylformamide (DMF) and N-methyl-2-pyrrolidone (NMP).

An antioxidant, an inorganic pigment, a lubricant, an antimicrobial agent, an antistatic agent, a stabilizer, a antiseptic agent and the like as an additive slurry in the form of a functional additive before spinning the polyurethane-urea spinning solution and mixing with a polyurethaneurea polymer solution. In addition, various functional additives such as a yellowing inhibitor, a UV stabilizer, a dyeability improver, a quencher, a radioactive enhancer, and a fluorescent brightener may be additionally used.

Antioxidants are used to capture radicals that cause decomposition of polymers generated by heat or sunlight. They may be BHT, phenol, benzotriazole, benzophenone, phosphorus, or amine. As the inorganic pigment, titanium dioxide, carbon black, etc. may be used for the purpose of quenching agent or color of the fiber. Fluorine resin, silicone resin, magnesium stearate, calcium stearate and the like can be used as the lubricant. The antimicrobial agent may be silver, zinc or inorganic compounds thereof. As the antistatic agent, silicone, mineral oil, barium sulfate, cerium oxide, betaine, phosphoric acid compound, phosphoric ester compound and the like can be used. 1,1,1 ', 1'-tetramethyl-4,4' (methylene-di-p-phenylene) disilecarbazide can be used as a stabilizer to prevent yellowing caused by nitrogen oxides. The anti-scavenging agent may be selected from a mixture of hydrotalcite, hydro-magneite, hantite, and hydro-magneite.

In order to use the insoluble fine particles as a functional additive, the insoluble fine particles are mixed with a solvent and then pulverized or dispersed to prepare an additive slurry, and the additive slurry is mixed with the polyurethane urea polymer solution to prepare a spinning solution. If it takes too long to make the additive slurry, the possibility of influx of water during pulverization or dispersion increases. In addition, moisture may also be introduced by the free water contained in the insoluble fine particles and the functional additive which are used.

In the present invention, a separate additive slurry is prepared and used to mix the functional additive with the spinning solution. The additive slurry for preparing polyurethane-urea elastic fibers according to an embodiment of the present invention includes a moisture removing agent for mixing the functional additive and removing moisture introduced into the additive slurry.

When the functional additive is in a liquid state, it is possible to prepare a slurry without using a separate solvent, and a liquid functional additive and other solid functional additive can be mixed and used. At this time, a water-removing agent may be mixed based on the total amount of the liquid type functional additive and the solid type functional additive.

The additive slurry can be variously changed from a paste form having a high viscosity to a slurry form having a low viscosity depending on the type of the functional additive and the content of the solvent. If the particles of the functional additive are small enough to require no separate grinding operation and the amount of the functional additive in solvent or liquid form is small, it can be produced in the form of a paste having a high viscosity. When an additive slurry is prepared in the form of a paste having a high viscosity, it is possible to prevent the dust from being scattered when the functional additive is added in the conventional slurry production process.

When an additive slurry is prepared in the form of a high viscosity paste, it can be directly added or mixed with a polymer solution in a state where a solvent is added and the viscosity is lowered.

In order to smoothly spin-form in a fiber form, the insoluble fine particles as a functional additive in the additive slurry may have a medium size (volume distribution basis) of about 10 탆 or less, preferably 5 탆 or less. More preferably 2.5 m or less. When the additive slurry is pulverized and mixed with the polyurethane-urea polymer solution, the additive slurry reduces the sediment on the inner surface of the spinneret when it is spun into polyurethane-urea elastic fibers, The effect of preventing the single yarns of the fibers is also prevented, and the insoluble fine particles imparting the functionality to the elastic fibers are uniformly distributed throughout the fibers, so that the functions of the elastic fibers are stabilized.

The additive slurry is mixed with a moisture removing agent which is contained in the functional additive or removes water that may be mixed in from the working environment.

As the moisture removing agent, potassium thiocyanate, potassium bromide, sodium carbonate, potassium carbonate, sodium nitrate, ammonium nitrate, sodium thiosulfate, calcium oxide, magnesium oxide and isocyanate compounds may be included.

A moisture removing agent that physically adsorbs moisture such as silica gel, molecular sieve, and alumina may be of some help in the gel formation in the spinning solution within a short time, but because the adsorbed water in the spinning solution continues to elute There is a problem that it acts as a cause of attenuating the performance of the polyurethane-urea elastic fiber. Since the moisture removing agent is insufficient only by the adsorption function as described above, water should be chemically reacted to lose its free water property.

Hygroscopic materials include sodium hydroxide, potassium hydroxide, ammonium nitrate, potassium cyanate, phosphorous pentoxide, glycerin, fructose, chloride, platinum chloride, hydrochloric acid, sulfuric acid, nitric acid, phenolic acid, iodine, potassium iodide, sodium, potassium, methyl alcohol, ethyl Wherein the organic acid is selected from the group consisting of alcohol, urea, acetic acid, formic acid, oxalic acid, glucose, sugar, gum arabic, lactose, calcium carbonate, potassium thiocyanate, potassium bromide, sodium carbonate, potassium carbonate, sodium nitrate, ammonium nitrate, ammonium thiosulfate, There are ferrous chloride, cobalt chloride, calcium chloride, tin chloride, tin chloride, zinc chloride, magnesium chloride, calcium oxide, magnesium oxide, manganese dioxide, ferric oxide, sodium peroxide and the like.

Chlorides such as ammonium chloride, ferric chloride, ferrous chloride, cobalt chloride, calcium chloride, stannous chloride, stannous chloride, zinc chloride, and magnesium chloride are effective in removing moisture, There is a problem that the durability of the urethane-urea elastic fiber is lowered.

The water-removing agent contained in the additive slurry according to the present invention should be such that the water chemically reacts to lose its free-water properties. Examples of the water-removing agent that is suitable for this purpose include white thiocyanate, potassium bromide, sodium carbonate, potassium carbonate, sodium nitrate, ammonium nitrate, sodium thiosulfate, calcium oxide and magnesium oxide.

Isocyanate is very reactive and readily reacts with compounds that have active hydrogens. In addition to alcohol, Amine, Amide, Urea, Urethane, Carboxylic acid, Epoxide and also reacts with water. The isocyanate compound is a compound such as TDI (toluene diisocyanate), MDI (methylene diphenyl diisocyanate) HDI (hexamethylene diisocyanate) IPDI (isophorone diisocyanate, Isophorone Diisocyanate) .

Figure 2 is a simplified representation of the reaction of isocyanate with water. As shown in Figure 2, the isocyanate reacts with water to form an amine, wherein the resulting amine reacts with another isocyanate to form urea. In this way, the free water contained in the solid material is removed by utilizing the urea reaction. In addition, some generated urea undergo crosslinking reaction (Crosslinking Reaction) which generates excess isocyanate and biuret under appropriate conditions.

The moisture removing agent includes 1.0 to 35 parts by weight based on the total amount of the functional additives contained in the additive slurry.

When the amount of the water-removing agent is 1.0 part by weight or less, the effect can not be expected. Potassium thiocyanate, potassium bromide, sodium carbonate, potassium carbonate, sodium nitrate, ammonium nitrate, sodium thiosulfate, calcium oxide, magnesium oxide and the like are polyurethane- It is difficult to increase the durability of the polyurethane-urea elastic fiber when it is used in excess of 35 parts by weight. Particularly, when the amount of the isocyanate compound is less than 1.0 part by weight, the effect thereof can not be expected. When the amount of the isocyanate compound is more than 35 parts by weight, excessive amount of unreacted isocyanate causes a change in the polyurethaneurea polymeric solution to inhibit the properties of the polyurethaneurea elastic fiber .

When the additional additive slurry is prepared as described above, the grinding time for reducing the size of the insoluble fine particles can be greatly reduced, and the moisture and the entrained water can be removed by the functional additive, It is possible to prevent deterioration of the quality of the resulting polyurethane-urea elastic fiber.

The additive slurry of the present invention may further contain a dispersant to improve the dispersibility of the functional additive. The dispersant may be selected from the group consisting of fatty acid, fatty acid salt, fatty acid ester, aliphatic alcohol dispersant, phosphate ester dispersant, phosphorylated block poly (alkylsiloxane) -poly (alkylene ether) alcohol modified or blocked with phosphoric acid ester system or aromatic or alkyl aromatic terminal Phosphorylated poly (alkylene ether) alcohol can be used.

When the dispersant is not used, the additive slurry can uniformly mix up to 1 to 20% by weight of the functional additive based on the total amount of the additive slurry. When the dispersant is used, uniform mixing and manufacture up to 50 to 70% It is possible. When the functional additive is 10 탆 or less, there is no need for pulverization, and only the mixing step with the water removing agent for removing water may be performed. At this time, it is also possible to use a paste-type additive slurry having a high viscosity by using a liquid functional additive or only a small amount of solvent.

Solvents usable in the present invention include dimethylacetamide (DMAc), dimethylformamide (DMF) and N-methyl-2-pyrrolidone (NMP) as liquid amides.

The additive slurry is prepared by mixing together at least one solvent and at least one functional additive, followed by pulverizing or dispersing. The additive slurry may also contain dispersants and other additives.

Hereinafter, the present invention will be described in more detail with reference to specific examples.

[Example 1]

A first polymer was prepared by charging polytetramethyleneether glycol (PTMEG, molecular weight 1815) and diphenylmethane-4,4'-diisocyanate (MDI) at a molar ratio of 1.70 (NCO / OH = 1.70).

The chain extender ethylenediamine, 1,2-propylenediamine and chain terminator diethylamine were dissolved in DMAc and added to the second polymerizer together with the first polymerizer to obtain a solid content ratio by the polymerization method of the polyurethaneurea elasticity yarn Polyurethane-urea secondary polymer solution having an apparent viscosity of about 35% and a viscosity of about 2000 to 3500 poise was obtained

As an additive slurry to be mixed with a polyurethane-urea secondary polymer solution polymerized by a chain extender and a chain stopper, conventional polyurethane-urea fibers maintain durability and whiteness during washing and use and improve discoloration resistance (prevention of yellowing) Based on the total weight of the irradiated polyurethane-urea fibers, 0.50% by weight of titanium dioxide, 1, 1, 1 ', 1 ' -tetramethyldisiloxane based on the total weight of the irradiated polyurethaneurea fibers to prevent or reduce damage to the mechanical properties, 0.50 wt% of tetramethyl-4,4 '(methylene-di-p-phenylene) disilecarbazide waste gas stabilizer (HN-150, Japan hydrazine), and 1,3,5-tris (CYANOX) of 1,4-t-butyl-3-hydroxy-2,6-dimethylbenzene) -1,3,5-triazine-2,4,6- (1H, 3H, 5H) 1790 < (R) > manufactured by Cynamid Co.), 1.44 wt% of antioxidant, and magnesium stearate (Japan, 0.30% by weight of poly (N, N-diethyl-2-aminoethyl methacrylate), 0.51% by weight of a dye-improving agent of poly (N, N-diethyl- 4.0 weight% of hydro magneite having a particle size of 10 占 퐉 or less (Nanitech Ceramics Co., Ltd., Airlite HM) and 5.0 parts by weight of calcium oxide as a moisture removing agent based on the total amount of the functional additive based on the functional additive were added.

The additive slurry was pulverized and dispersed by a wet pulverizer so that the size of the inorganic particles was 10 mu m or less. Here, in order to crush the functional additive in the additive slurry, pulverization was carried out until the mean particle size of the functional additive was less than 10 탆 by using a wet pulverizer, the filter test of the slurry was performed using a 20 탆 filter, . Since uniform mixing of the polyurethane urea polymer solution and the additive slurry is important at this time, a cylindrical pipe homogenizer (Static Mixer) was used to uniformly mix the additive slurry and the polyurethane urea solution. The polyurethane-urea spinning solution thus prepared obtained a spinning solution having a viscosity of 4350 poise (40) containing about 35% solids and a viscosity suitable for spinning.

Polyurethane elastic fibers were produced at 900 m / min using a dry spinning method in which the spinning solution thus prepared was pumped by a gear pump with a spinneret having an atmosphere of 250 and the solvent was evaporated. Respectively.

The moisture content of the additive slurry was measured with a Karl Fischer moisture meter (MKC-710, Kyoto Electronics Manufacturing Co. Ltd., Japan). Since the water content varies with the amount of solvent, the moisture content based on the functional additive is indicated.

The fracture strength and the elongation at break were measured by a tensile tester (UTM, manufactured by Instron Corporation) at 25 and 65% RH at a sample length of 5 cm and at a rate of 50 cm / min to determine the strength (g / d) The restorative length (Lw) was measured after removal of the elongation after treatment for 60 minutes under 130 steam atmosphere under the condition of 100% market, and the length of untreated sample . When the elastic recovery rate is high, the heat resistance is high and the heat setting property is low. The ratio of strength after dry heat treatment to the strength of untreated sample is regarded as the strength retention rate, and the higher the retention rate, the more heat resistance Is high. The anti-chlorinability was measured by immersing the sample in a bath having a pH of 7 and having an effective chlorine concentration of 20 ppm at 50% elongation. The ratio of the strength of the sample to the strength of the sample after 24 hours and 48 hours was regarded as a strong retention rate. Also, the elastic recovery rate is measured by measuring the sample length before and after the chlorine treatment, and the higher the recovery rate, the higher the anti-chlorine.

[Example 2]

The elastic yarn was prepared in the same manner as in Example 1, except that 1.0 parts by weight of calcium oxide as the moisture removing agent of the present invention was used based on the total weight of the functional additive.

[Example 3]

The elastic yarn was prepared in the same manner as in Example 1, except that calcium oxide was used as the moisture removing agent of the present invention in an amount of 9.0 parts by weight based on the total weight of the functional additive.

[Example 4]

The elastic yarn was prepared in the same manner as in Example 1, except that 5.0 parts by weight of TDI (toluene diisocyanate) as the moisture removing agent of the present invention was used based on the total weight of the functional additive.

[Example 5]

The elastic yarn was prepared in the same manner as in Example 1 except that 25.0 parts by weight of TDI (toluene diisocyanate) as the moisture removing agent of the present invention was used based on the total weight of the functional additive.

[Example 6]

The elastic yarn was prepared in the same manner as in Example 1 except that 5.0 parts by weight of sodium nitrate was used as the moisture removing agent of the present invention based on the total weight of the functional additive.

[Comparative Example 1]

The elastic yarn was produced in the same manner as in Example 1 without using the moisture removing agent of the present invention.

[Comparative Example 2]

The elastic yarn was prepared in the same manner as in Example 1, except that 40.0 parts by weight of calcium oxide was used as the moisture removing agent of the present invention based on the total weight of the functional additive.

division Moisture content
(g / 100 g) Yarn characteristics Heat-resistant property Anti chlorine property Breaking strength
(g / d) Judgment
(g / d) 130 ℃ wet heat
Elastic recovery rate
(%) 180 ℃ dry heat
Strong retention rate
(%) 24 hours
After processing
Strong retention rate 48 hours
After processing
Strong retention rate Example 1 0.48 1.40 520 45 80 94 90 Example 2 1.70 1.35 500 43 76 92 88 Example 3 0.13 1.35 510 43 77 91 87 Example 4 1.51 1.35 510 43 75 92 89 Example 5 0.01 1.35 500 43 76 91 88 Example 6 0.56 1.40 510 44 78 94 89 Comparative Example 1 2.00 1.35 500 43 69 90 86 Comparative Example 2 0.01 0.9 480 40 65 48 cinnabar * Moisture Content = Water Content (g) / Functional Additive Content (100g)

As can be seen from the above Examples and Comparative Examples, the polyurethane-urea elastic fibers according to the production method of the present invention had no single yarn and overall durability was improved.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, You will understand.

It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention .

Claims (4)

A functional additive, a moisture removing agent and a moisture removing agent,
Wherein the functional additive is contained in an insoluble particulate state, the insoluble fine particles have an average particle diameter of 10 mu m or less,
Wherein the moisture removing agent comprises an isocyanate compound,
Wherein the moisture removing agent is contained in an amount of 1.0 to 35.0 parts by weight based on the total amount of the functional additive contained in the additive slurry.
The method according to claim 1,
Further comprising a dispersing agent,
The dispersant may be at least one selected from the group consisting of fatty acid, fatty acid salt, fatty acid ester, aliphatic alcohol dispersant, phosphate ester dispersant, phosphorylated block poly (alkylsiloxane) -poly (alkylene ether) alcohol denatured and blocked with phosphoric acid ester, (Alkylene ether) alcohol and an alkyl aromatic terminal phosphorylated poly (alkylene ether) alcohol.
delete The method according to claim 1,
The isocyanate compound may be at least one of TDI (toluene diisocyanate), MDI (methylene diphenyl diisocyanate) HDI (hexamethylene diisocyanate) IPDI (isophorone diisocyanate) ≪ / RTI > additive slurry for the production of polyurethaneurea elastic fibers.

Images