JPH05156514A - Polyurethane fiber - Google Patents

Abstract

PURPOSE:To obtain the subject fiber, composed of a polyurethane produced by reacting a polymer diol with an organic diisocyanate, a prepolymer type organic polyisocyanate containing a specific piperidine side chain and a chain extender, excellent in discoloration, light and heat resistance, flexibility and elastic recovery properties and useful as swimming wear, etc. CONSTITUTION:The objective fiber is composed of a polyurethane produced by reacting a polymer diol such as a polyester polyol with an organic diisocyanate such as 4,4'-diphenylmethane diisocyanate and preferably 0.1-20wt.% prepolymer type organic polyisocyanate, e.g. expressed by the formula [R<1> to R<4> are alkyl; R<5> is direct bond or bivalent group; A and B are monovalent group; only either of A and B is active hydrogen reactive with the isocyanate; m is >=1] and having a group containing piperidine ring in which the 2- and 6-positions are respectively substituted with two alkyl groups in a pendant state in the side chain, >=1500 average molecular weight and 1.8-3 number of average isocyanate groups and a chain extender.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to polyurethane fibers. More specifically, it relates to a polyurethane fiber having excellent flexibility, heat resistance, weather resistance, discoloration resistance and the like.

[0002]

2. Description of the Related Art Polyurethane fibers are called spandex and have excellent elasticity not found in other fibers. Therefore, they are suitable for sports clothing such as swimwear and ski wear, underwear,
It is widely used for various purposes such as stockings, elastic bandages, and medical materials such as artificial blood vessels. However, the polyurethane fiber gradually turns yellow over time after production due to outdoor exposure to sunlight, NO _x gas, automobile exhaust gas, etc., contact with chemical substances such as chlorine bleach and organic solvents, etc. It has drawbacks such as deterioration of mechanical properties such as strength and elongation. Polyurethane fibers with a polyether diol such as polytetramethylene glycol as a soft segment are particularly resistant to light due to the low light resistance of the ether bond. The sex is inferior.

Various attempts have been made to improve the above-mentioned drawbacks of polyurethane fibers, particularly the light resistance. For example, it is known that a large amount of a matting agent such as titanium oxide is blended in polyurethane fiber to aim at the effect of shielding sunlight, but when it is used for a stretchable fabric, particularly when it is dyed in a dark color. It has the disadvantage that it becomes whitish and does not have a deep color, and it becomes of low quality.

Further, a stabilizer such as a light resistance stabilizer or an ultraviolet absorber made of a hindered amine compound having a piperidine ring in which the 2-position and the 6-position are each substituted with two alkyl groups, that is, a hindered piperidine ring is used in polyurethane. It has been conventionally practiced to add to the above to produce fibers.
However, when the stabilizer is simply added, the solubility of the stabilizer in the stock solution for spinning is not good when the fiber is produced by the dry spinning method or the wet spinning method, or the stabilizer is used at the time of desolvation during spinning. Has the drawback of being detached from the fiber. Further, in the case of the melt spinning method, there are drawbacks such that the stabilizer volatilizes and adheres to the spinneret to generate stains and cause yarn breakage. In addition, there is a problem that the stabilizer migrates to the surface of the polyurethane fiber, causing a blooming phenomenon, and easily falling off from the fiber by washing with water or cleaning.

Therefore, in order to solve the above problems, there has been proposed a method of chemically bonding a hindered amine compound containing a hindered piperidine ring to polyurethane for fibers and films. Conventionally proposed methods for chemically bonding hindered amine compounds include a method of using a hindered amine compound as a terminal terminating agent during polyurethane production, and a hindered amine compound used as a chain extender to form a side chain of a hindered piperidine ring in the hard segment of polyurethane. And the method of introducing the hindered piperidine ring itself into the main chain of polyurethane. The above and the methods are described in JP-A-53-39395 and JP-A-55-18409. The above method is described in JP-A-53-1294.

However, in the case of the above method, the hindered amine compound acts as a terminal terminating agent, which is an obstacle in increasing the degree of polymerization of polyurethane.
In particular, when a large amount of hindered amine compound is used in order to further improve the weather resistance and discoloration resistance of polyurethane, it is impossible to produce polyurethane having a desired degree of polymerization because the polyurethane is terminated at an extremely low degree of polymerization. There are drawbacks and the amount of hindered amine compound used is limited.

Further, in the case of the above method, the presence of a bulky hindered piperidine ring as a side chain in the hard segment portion hinders the formation of a crosslinked structure due to hydrogen bonding between the hard segments, and the original polyurethane There are drawbacks that excellent mechanical properties such as elasticity recovery and tensile strength are likely to be deteriorated and heat resistance is easily lost.

In the case of the above method, the polyurethane main chain is cleaved by light at the nitrogen atom portion of the piperidine ring in the polyurethane main chain, similarly to the radical scavenging mechanism known as the light stabilization mechanism of the hindered amine compound. Therefore, the polyurethane has a drawback that the light resistance of the polyurethane is not improved, and when exposed to light, the main chain is likely to be broken and mechanical strength is apt to be lowered.

[0009]

From the above point of view, the inventors of the present invention have the above-mentioned prior art in which a matting agent or stabilizer such as titanium oxide is simply added to the polyurethane fiber, and the prior arts mentioned in the above (1) to (3). Studies have been carried out with the aim of obtaining excellent polyurethane fibers in which a hindered amine compound is chemically bonded in a polyurethane molecule without causing defects. As a result, the hindered amine compound containing a hindered piperidine ring was used as a side chain in a prepolymer type organic polyisocyanate having a molecular weight of a predetermined value or more without using the hindered amine compound as a terminal stopper or a chain extender. By incorporating and using the prepolymer as at least a part of the organic diisocyanate used in producing a polyurethane and forming a fiber from such a polyurethane, it is possible to achieve the above object and obtain an excellent polyurethane fiber. The present invention has been completed by finding out.

Accordingly, the present invention provides a polymeric diol,
A fiber comprising a polyurethane produced by using an organic diisocyanate and optionally a chain extender,
The polyurethane has, as at least a part of the organic diisocyanate, a group containing a piperidine ring in which the 2-position and the 6-position are each substituted with two alkyl groups in a side chain in a pendant form, and the average molecular weight is 1500 or more. And a polyurethane fiber produced by using a prepolymer type organic polyisocyanate having an average number of isocyanate groups of 1.8 to 3.

In the present invention, the above-mentioned "group having a piperidine ring in which the 2- and 6-positions are each substituted with two alkyl groups is pendant in the side chain and has an average molecular weight of 1500 or more and Average number of isocyanate groups is 1.8
~ 3 prepolymer type organic polyisocyanate "(hereinafter referred to as" piperidine side chain-containing prepolymer ") is 15
An average molecular weight of 00 or more, preferably 2000 to 1000
It has an average molecular weight of 0, a hindered piperidine ring is present as a side chain in the prepolymer in a pendant form, and the average number of isocyanate groups is 1.8 to 3, preferably 1.9 to 2.8. Any of the above may be used, and the manufacturing method thereof is not particularly limited.

Although not limited to the following,
In order to facilitate understanding of the content of the piperidine side chain-containing prepolymer used in the present invention, an example of a preferable production method thereof will be described below.

Preparation Example of Piperidine Side Chain-Containing Prepolymer (1) A relatively high molecular weight polyol such as a polyester polyol or polyether polyol having an active hydrogen atom number F such as a hydroxyl group of 2 <F <4, and an organic poly Isocyanates (preferably organic diisocyanates) are reacted to produce isocyanate terminated prepolymers having an average number of isocyanate groups greater than 2, preferably 2.2 to 3.8. (2) A hindered amine compound containing the piperidine ring, which has one isocyanate-reactive active hydrogen atom and is substituted with two alkyl groups at the 2- and 6-positions, respectively, in the isocyanate-terminated prepolymer produced in (1) above. To
A prepolymer having an average of 1.8 to 3 unreacted isocyanate groups remaining and having a hindered piperidine ring as a side chain in a pendant form by reacting a smaller amount than the isocyanate group equivalent of the isocyanate terminated prepolymer. The above-mentioned piperidine side chain-containing prepolymer having an average molecular weight of 1500 or more bound to the above is produced.

As the polyol with 2 <F <4 used in the above step (1), at least one low molecular weight polyol having three or more hydroxyl groups such as glycerin, trimethylolpropane and pentaerythritol is present. In addition, at least one low molecular weight polyol having 3 or more hydroxyl groups such as polyester polyol of 2 <F <4 produced by reacting an organic dicarboxylic acid and a low molecular weight diol, glycerin, trimethylolpropane, and pentaerythritol, At least one low molecular weight polyol having 3 or more hydroxyl groups such as polyester polyol of 2 <F <4, glycerin, trimethylolpropane and pentaerythritol produced by reacting a lactone compound together with glycol, ethylene oxide, Propylene The alkylene oxide of the side like reacted can be mentioned polyether polyols is 2 <F <4, prepared. And, those polyester polyols and polyether polyols are usually about 30
It is desirable to have an average molecular weight of 0 to 5000, especially about 500 to 3000.

Further, as the organic polyisocyanate used in the above step (1), it is preferable to use an organic diisocyanate. As such an organic diisocyanate, 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, 1 , 5-naphthalene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate and the like can be mentioned, and it is preferable to use one kind or two or more kinds of these organic diisocyanates.

The "hindered amine compound containing a piperidine ring having one isocyanate-reactive active hydrogen atom and each substituted with two alkyl groups at the 2- and 6-positions" used in the above step (2). As long as it has a total of four alkyl groups bonded to the 2- and 6-positions of the piperidine ring and has one isocyanate-reactive active hydrogen atom, it is known in this type of technique. Any of the hindered amine compounds mentioned above can be used. Representative examples of the hindered amine compound include compounds represented by the following formula (I).

[0017]

[Chemical 1] (In the formula, R ¹ , R ² , R ³ and R ⁴ are each an alkyl group, R ⁵ is a direct bond or a divalent group, A and B are each a monovalent group, and A and B Only one has an isocyanate-reactive active hydrogen atom and m is 1
The above is the number)

In the compound of formula (I) above, R ¹ ,
Each of R ² , R ³ and R ⁴ is preferably a lower alkyl group having 1 to 4 carbon atoms, and particularly preferably all of the 4 alkyl groups are methyl groups. When R ⁵ is a divalent group, it may be a divalent hydrocarbon group such as an alkylene group or an arylene group, or a divalent group having an ester bond, an ether bond, a thioether bond, an amide bond or the like. it can. Further, one of A and B is a group having an isocyanate-reactive active hydrogen atom, preferably an amino group, a hydroxyl group, a carboxyl group, or another monovalent group having a hydroxyl group, an amino group or a carboxyl group (for example, Aminomethyl group, hydroxymethyl group, aminoethyl group, etc.), and the other one of A and B does not have an isocyanate-reactive active hydrogen atom such as an alkyl group, an aryl group, an alkoxy group or an aryloxy group.
It is a valence group. Further, m is preferably 1 to 20.

Specific examples of the hindered amine compound contained in the compound represented by the formula (I) include the following formula (II).
1-methyl-2,2,6,6-tetramethyl-4-hydroxypiperidine represented by the formula: 1-methyl-2,2,6,6-tetramethyl-4- represented by the following formula (III)
Examples thereof include aminopiperidine, compounds represented by the following formula (IV), and the like.

[0020]

[Chemical 2]

[0021]

[Chemical 3]

[0022]

[Chemical 4] (In the formula, n represents a number of 2 to 20)

Of the above hindered amine compounds, the compound represented by the formula (IV) is preferable because it can introduce a plurality of hindered piperidine rings into the piperidine side chain-containing prepolymer molecule.

In the piperidine side chain-containing prepolymer used in the present invention, the proportion of the hindered amine compound is about 5 to 70%, preferably about 10 to 60% based on the weight of the piperidine side chain containing prepolymer. Is preferable from the viewpoints of improving the weather resistance, light resistance, discoloration resistance, heat resistance and the like of polyurethane and maintaining good mechanical properties. Then, the reaction (2) for producing the piperidine side chain-containing prepolymer is usually carried out at a temperature of about 50 to 200 ° C, preferably about 70 to 160 ° C.

The polyurethane used for producing the polyurethane fiber of the present invention can be produced by the one-shot method, the prepolymer method, or the other method using a polymer diol, an organic diisocyanate and a chain extender if necessary. It can be manufactured by a method. At that time, the piperidine side chain-containing prepolymer produced above may be reacted at the same time when producing a polyurethane by the one-shot method or the prepolymer method, or a polyurethane not containing a hindered piperidine side chain may be prepared by the one-shot method. Alternatively, after production by the prepolymer method, a piperidine side chain-containing prepolymer is added to the polyurethane at any stage until the spinning is completed and reacted to chemically bond the hindered piperidine side chain to the molecule of the polyurethane. May be.

In any of the above methods,
The bond ratio of the hindered piperidine ring in the finally obtained polyurethane is not particularly limited, but in consideration of the effect of improving light resistance and weather resistance and the economical efficiency, it is usually based on the total weight of the raw materials for polyurethane. , Piperidine side chain-containing prepolymer usage ratio is about 0.1-20%
It is desirable to manufacture the polyurethane as follows.

The above-mentioned polymer diol used in the one-shot method, the prepolymer method or the like is preferably one having an average molecular weight of 500 to 5,000, preferably 1,000 to 3,000. As the polymer diol, at least one kind of polyester diol, polycarbonate diol, polyether diol, polyether ester diol and the like can be used, but polyester diol and polycarbonate diol are particularly preferable.

As the polyester diol, at least one of dicarboxylic acids (eg, succinic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, etc.) is used.
Seeds and low molecular diols (eg ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2-methyl-1,8).
-Octanediol, 1,9-nonanediol, 1,1
And a polylactone diol such as polycaprolactone diol obtained by ring-opening polymerization of a lactone compound and polymethyl valerolactone diol.

As the polycarbonate diol, for example, at least one kind of dialkyl carbonate (dimethyl carbonate, diethyl carbonate, ethylene carbonate, etc.) and low-molecular diol (for example, ethylene glycol, propylene glycol, 1,
4-butanediol, neopentyl glycol, 1,6
-Hexanediol, 3-methyl-1,5-pentanediol, 2-methyl-1,8-octanediol, 1,
There may be mentioned a polycarbonate diol produced from at least one of 9-nonane diol and 1,10-decane diol.

Further, as the polyether diol, polyether diol obtained by ring-opening polymerization of cyclic ether (polyethylene oxide, polypropylene oxide, trimethylene oxide, tetrahydrofuran, etc.), glycol (ethylene glycol, propylene glycol, 1,4-) Butanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5
-Pentane diol, 2-methyl-1,8-octane diol, 1,9-nonane diol, 1,10-decane diol, etc.) are preferred.

As the polyether ester diol, those produced by reacting the above-mentioned polyester diol with the above-mentioned cyclic ether, those obtained by reacting the above-mentioned polyester diol with polyether diol, and the like are used. You can

As the organic diisocyanate other than the above-mentioned piperidine side chain-containing prepolymer, 4,
4'-diphenylmethane diisocyanate, tolylene diisocyanate, 1,5-naphthalene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and other organic diisocyanates having a molecular weight of 500 or less can be mentioned. May be used alone or in combination of two or more. Particularly, 4,4'-diphenylmethane diisocyanate is preferable.

As the chain extender, it is preferable to use a low molecular weight compound having two active hydrogen atoms capable of reacting with an isocyanate group. For example, ethylene glycol, propylene glycol, 1,4-butanediol, 1 , 6
-Hexanediol, 1,9-nonanediol, 1,4
-Bis (β-hydroxyethoxy) benzene, 1,4-
Cyclohexanediol, diols such as xylylene glycol, ethylenediamine, propylenediamine, xylylenediamine, isophoronediamine, 4,4′-diaminodiphenylmethane, tolylenediamine, 4,4 ′
Diamines such as diaminodicyclohexylmethane may be mentioned, and only one of these chain extenders or 2
More than one species can be used. Among them, 1,4-butanediol and 1,4-bis (β-hydroxyethoxy) benzene are particularly preferable.

Then, a polyurethane for fiber production is produced regardless of the one-shot method and the prepolymer method, and whether or not the organic diisocyanate contains the piperidine side chain-containing prepolymer during the reaction thereof. In this case, various known batch-type or continuous-type methods and apparatuses can be adopted. In particular, it is preferable to carry out the polymerization of polyurethane in a molten state in the substantial absence of a solvent, and it is more preferable to carry out continuous melt polymerization using an extruder such as a multi-screw type. The temperature at that time is not particularly limited, but it is usually preferable to carry out in the range of about 200 to 260 ° C., and by keeping the temperature at the time of polymerization at 260 ° C. or lower, the heat resistance and mechanical properties of the fiber are improved, while By keeping the temperature at 200 ° C. or higher, a thermoplastic polyurethane having excellent melt spinnability can be produced. At that time, it is preferable to set the ratio (R value) of the isocyanate groups in the raw material to the active hydrogen atoms in the range of 1.0 to 1.1.

In the production of polyurethane,
If necessary, use optional components such as catalysts, activators, defoamers, other stabilizers, colorants such as dyes and pigments, fillers, flame retardants, lubricants, etc. that are usually used in the production of polyurethane. can do.

When the above-mentioned piperidine side chain-containing prepolymer is used as at least a part of the organic diisocyanate to produce a polyurethane fiber, (1) a polymer diol and a piperidine side chain-containing prepolymer are contained as at least a part. A method in which a hindered piperidine side chain-containing polyurethane is produced in advance by a one-shot method or a prepolymer method from an organic diisocyanate and, if necessary, a chain extender, and melt spinning is performed using the polyurethane. (2) The above (1) Similarly, a method in which a hindered piperidine side chain-containing polyurethane is prepared in advance, and then the polyurethane is dissolved in a solution to prepare a spinning dope, and dry spinning or wet spinning is performed. (3) Polymer diol, piperidine side chain containing prepolymer Polymer-free organic diisocyanates And, if necessary, from a chain extender, a polyurethane is produced in advance by a one-shot method or a prepolymer method, and then the above-mentioned piperidine side chain-containing prepolymer is added to the polyurethane at any stage until completion of melt spinning. Then, a method for producing a polyurethane fiber in which a hindered piperidine side chain is chemically bonded to a polyurethane molecule, (4) a polymer diol and an organic diisocyanate containing at least a part of the piperidine side chain-containing prepolymer as a prepolymer Can be formed by spinning the prepolymer into a solution containing a chain extender such as a diamine and polymerizing it in a spinning bath.

Among the methods (1) to (4) described above, the melt spinning methods (1) and (3) which do not use a solvent or water are simple and efficient in terms of steps, It is particularly preferable because it has high safety and there is no risk of environmental pollution. When producing polyurethane fibers by the melt spinning method, 4,4′-diphenylmethane diisocyanate is used as the organic diisocyanate together with the piperidine side chain-containing prepolymer described above, polyester diol is used as the polymer diol, and chain extender is used as the chain extender. When a polyurethane produced by using 1,4-butanediol and / or 1,4-bis (β-hydroxyethoxy) benzene is used, a fiber having excellent heat resistance, elastic recovery and elongation can be obtained. ..

The spinning apparatus and spinning conditions used for melt spinning depend on the content of polyurethane, the thickness of the target fiber, the melt spinning method of the above (1) or the melt spinning method of the above (3), and the like. Although it can be varied, when using an extrusion type spinning machine, usually, pellets of polyurethane with or without hindered piperidine side chains are fed to the extrusion type spinning machine and melted, and the spinning temperature is about 180 to 24.
Spinning is preferably performed at 0 ° C. and a spinning speed of about 900 m / min or less, particularly 600 m / min or less. The apparent draft ratio (area of nozzle single hole / cross-sectional area of single fiber) is 50 or more, preferably 100 or more, more preferably 150 or more. The spinning tension when the spun yarn is wound on the bobbin by the winder is 0.1 g / d or less, preferably 0.05 g / d or less, and the feeding speed from the godet roller to the winder is It is preferable that the difference does not exceed 5% underfeed, and it is particularly preferable to approach the constant velocity.

In addition, the wound yarn is kept under low humidity at + 20 ° C. to the glass transition point (Tg) of the hard segment.
It is preferable to perform heat treatment in the range of −50 ° C. to sufficiently perform phase separation between the hard segment and the soft segment. And, by the above method, generally, the thickness is about 5
100 denier / filament polyurethane fiber can be obtained.

The present invention will be specifically described below with reference to examples and the like, but the present invention is not limited thereto. Moreover, parts in the following examples represent parts by weight. Further, in the following examples, the strength and elongation of polyurethane fibers, the instantaneous elastic recovery rate, the light resistance strength retention rate, the solvent extractability and the quantification of the isocyanate group of the produced prepolymer were measured by the following methods.

<< Measurement of Strength and Elongation >> The strength and elongation was determined according to JIS L-1013.

<< Measurement of Instantaneous Elastic Recovery Rate >> The instantaneous elastic recovery rate of 200% elongation of the polyurethane fiber at 20 ° C. was determined. Instantaneous elastic recovery means the return property immediately after removing stress by holding it for 2 minutes after stretching by 200% (JIS.
L-1096), and is calculated by the following mathematical formula 1. Further, the extension speed and the unloading speed at that time are both 500
mm / min.

[0043]

## EQU1 ## Instantaneous elastic recovery rate (%) = 100 × [(n + 1)
LL ′] / nL [where n is the elongation ratio, L is the initial length, L ′ is the length after stress relief, and (n + 1) L is the length at the time of elongation]

<< Measurement of Light-Resistant Strength Retention Ratio >> A polyurethane fiber produced in each of the following examples was wound on a frame under a tension of 5/1000 g / denier, and a carbon arc type fade manufactured by Suga Test Instruments Co., Ltd. The strength retention was determined by irradiating with ultraviolet light at a temperature of 83 ° C. for 20 hours using a meter FAL-5 type. The strength retention rate was calculated from the following Equation 2 using an autograph manufactured by Shimadzu Corporation.

[0045]

[Formula 2] Strength retention rate (%) = (strength after ultraviolet irradiation / strength before ultraviolet irradiation) × 100

<< Measurement of Solvent Extractability >> The polyurethane fibers produced in each example were wound on a frame under a tension of 5/1000 g / denier, and immersed in Perkren at 70 ° C. for 5 hours at a bath ratio of 1: 1000. Then, the light resistance strength retention of the product dried at 50 ° C. for 1 hour was obtained.

<Determination of Isocyanate Group> 0.1 g of a reaction solution containing a prepolymer was added to 0.01 N di-n-
After adding and dissolving in 40 ml of a dimethylformamide solution of butylamine, neutralization titration was performed with 0.01 M hydrochloric acid in methanol using bromphenol blue as an indicator to perform quantification.

The compounds used in each example are as shown by the following abbreviations. MDP : 3-methyl-1,5-pentanediol BD : 1,4-butanediol TMP : trimethylolpropane AD : adipic acid AZ : azelaic acid PMAZ : polyester of average molecular weight 2000 obtained by reacting MPD and AZ Diol PMPA : Polyester diol having an average molecular weight of 2000 obtained by reacting MPD and AD MDI : 4,4'-diphenylmethane diisocyanate 622LD : Hindered amine compound represented by the above formula (IV) (light stabilizer of Ciba Geigy; tinuvin 62
2LD, molecular weight 3400) LS-765 : a hindered amine compound represented by the following formula (V) having neither an isocyanate group nor an active hydrogen atom.

[0049]

[Chemical 5]

Reference Example 1 [Production of Trifunctional Polyester] 134 parts of TMP, 460 parts of MPD, 603 parts of AZ and 0.05 part of titanium tetraisopropoxide were passed under nitrogen under normal pressure while the produced water was distilled at 210 ° C. Esterification was performed while leaving. When the acid value reached about 50, the degree of vacuum was gradually raised by a vacuum pump to complete the reaction. As a result, a trifunctional polyester triol (polyester A) having a hydroxyl value of 168, an acid value of 0.5 and an average molecular weight of 1000 was obtained.

Reference Example 2 [Production of Trifunctional Polyester] TMP, MPD, AZ and titanium tetraisopropoxide were used to carry out a condensation reaction in the same manner as in Reference Example 1 to give a hydroxyl value of 84 and an acid. Value 0.3 and average molecular weight 200
A trifunctional polyester triol of 0 (Polyester B) was obtained.

Reference Example 3 [Production of trifunctional polyester] TMP, MPD, AD and titanium tetraisopropoxide were used to carry out a condensation reaction in the same manner as in Reference Example 1 to give a hydroxyl value of 168 and an acid. Value 0.4 and average molecular weight 10
A trifunctional polyester triol of 00 (polyester C) was obtained.

Reference Example 4 [Production of Piperidine Side Chain-Containing Prepolymer] 100 parts of Polyester A was placed in a reaction vessel sealed with nitrogen, and 75 parts of MDI was added while maintaining at 90 ° C.
After reacting for a minute, the residual amount of isocyanate groups was determined by the above-mentioned quantitative method to be 49.9 mol%.
Next, 113 parts of 622LD was added and reacted for 1 hour to obtain a piperidine side chain-containing prepolymer (prepolymer D). The residual amount of isocyanate groups in the prepolymer D was 9.26 × 10 ⁻⁴ equivalent / g, the average number of functional groups (average number of isocyanate groups) was 2.65, and the binding amount (content) of 622 LD in the prepolymer D was 39. ．
It was 2% by weight.

Reference Examples 5 to 8 [Production of Piperidine Side Chain-Containing Prepolymer] Instead of Polyester A, the polyesters shown in Table 1 below were used in the amounts shown in Table 1, and shown in Table 1. Amount of MDI and 622LD, or 622LD
In the same manner as in Reference Example 4, except that the piperidine side chain-containing prepolymer (prepolymer E to
G) and a piperidine side chain-free prepolymer (prepolymer H) were prepared. The average number of isocyanate groups and the content of 622 LD of these prepolymers are as shown in Table 1.

[0055]

[Table 1]  Reference example 4 Reference example 5 Reference example 6 Reference example 7 Reference example 8 Prepolymer raw material  Polyester type A B C C B Polyester amount (part) 100 200 100 100 200 MDI usage amount (part) 75 75 75 75 75 622 LD usage amount (part) 113 113 113 226 0Generated prepolymer  Species D E F G H NCO Equivalent (eq / g) 9.26 x 10^-Four 6.88 x 10^-Four 9.26 x 10^-Four 5.82 x 10^-Four 5.82 x 10^-Four  Average number of functional groups 2.65 2.65 2.65 2.33 3.00 622 LD content (wt%) 39.2 29.1 39.2 56.3 0 Average molecular weight 2880 3880 2880 4010 2750

Examples 1 to 6 [Production of Polyurethane Fiber] Mixtures containing polyester diol and BD shown in Table 2 below in the proportions shown in Table 2 and heated to 80 ° C. and MDI heated to 50 ° C. Was continuously fed to a twin-screw extruder by a metering pump, and the piperidine side chain-containing prepolymers (prepolymers D to G) shown in Table 2 heated to 150 ° C. were continuously fed by a static mixer. Continuous melt polymerization was performed, and the produced polyurethane was extruded into water in a strand shape and cut to produce polyurethane pellets.

After vacuum-drying the above pellets at 80 ° C. for 20 hours, a conventional spinning machine equipped with a single-screw extruder spins at a temperature of 235 ° C., spinning speed is 500 m / min, and apparent draft rate is 84.
7, spinning tension 0.08 g / d, yarn feeding speed difference 35
Spinning was performed at m / min to obtain a polyurethane raw yarn of 40 denier / 1 filament. After aging this raw yarn at 80 ° C. for 48 hours, the strength and elongation, instantaneous elastic recovery rate,
The light resistance strength retention rate and the solvent extractability (light resistance strength retention rate after the solvent extraction treatment) were measured. The results are shown in Table 2 below.
Shown in.

Examples 7 to 8 [Production of Polyurethane Fiber] A mixture containing polyester diol and BD shown in Table 2 below in the proportions shown in Table 2 and heated to 80 ° C. and MDI heated to 50 ° C. Was continuously supplied to a twin-screw extruder by a metering pump to perform continuous melt polymerization, and the produced polyurethane was extruded into water in a strand form and cut to produce polyurethane pellets.

The above pellets were vacuum dried at 80 ° C. for 20 hours, then extruded by a twin-screw extruder and heated to 150 ° C. from the middle of the cylinder, and the piperidine side chain-containing prepolymer shown in Table 2 (prepolymer D or prepolymer D or F) is continuously fed by a static mixer, and the spinning temperature is 235
℃, spinning speed 500m / min, apparent draft rate 847,
Spinning was carried out with a spinning tension of 0.08 g / d and a yarn feeding speed difference of 35 m / min to obtain a polyurethane raw yarn of 40 denier / 1 filament. After aging this raw yarn for 48 hours at 80 ° C., the strength and elongation, the instantaneous elastic recovery rate, the light resistance strength retention rate and the solvent extractability (light resistance strength retention rate after the solvent extraction treatment) were measured by the methods described above. .. The results are shown in Table 2 below.

Comparative Example 1 [Production of Polyurethane Fiber] A polyurethane fiber was produced in the same manner as in Example 1 except that the prepolymer H containing no hindered piperidine ring was used as the prepolymer, and the strength and elongation thereof were increased. The instantaneous elastic recovery rate, light resistance strength retention rate and solvent extractability (light resistance strength retention rate after solvent extraction treatment) were measured. The results are shown in Table 2 below.

Comparative Examples 2 to 3 [Production of Polyurethane Fiber] Polyurethane fiber was produced in the same manner as in Example 1 except that the prepolymer was not used at all, and its strength and elongation, instantaneous elastic recovery rate, The light resistance strength retention rate and the solvent extractability (light resistance strength retention rate after the solvent extraction treatment) were measured. The results are shown in Table 2 below.

Comparative Examples 4 to 5 [Production of Polyurethane Fiber] LS-765 was added in place of the prepolymer D at a compounding amount of 1.0% by weight when extruded by a twin-screw extruder. Other than that, polyurethane fibers were produced in the same manner as in Example 7, and the strength and elongation, instantaneous elastic recovery rate, light resistance strength retention rate and solvent extractability (light resistance strength retention rate after solvent extraction treatment) were measured. .. The results are shown in Table 2 below.

[0063]

[Table 2]

In Table 2, the content of the light stabilizer in Examples 1 to 8 (% by weight) means the ratio of 622 LD chemically bonded to polyurethane in the form of a piperidine side chain-containing prepolymer. From the results in Table 2 above, the fibers of Examples 1 to 8 of the present invention, which are made of polyurethane using the piperidine side chain-containing prepolymer as a part of the organic diisocyanate, have extremely high light resistance strength retention ratio and excellent light resistance. Therefore, it can be seen that the excellent light resistance hardly deteriorates even after the solvent extraction treatment. On the contrary,
Comparative Examples 1 to 1 to which no hindered amine compound was added
It can be seen that the polyurethane fiber of No. 3 has a very low light resistance strength retention rate after ultraviolet irradiation and is inferior in light resistance. In addition, Comparative Examples 4 to 6 containing a non-reactive hindered amine compound having no isocyanate group or active hydrogen atom
In No. 5, the light resistance is lost by the solvent extraction treatment.

[0065]

EFFECT OF THE INVENTION The polyurethane fiber of the present invention is used in sunlight, NO
_x Very little yellowing due to outdoor exposure to gas, automobile exhaust gas, etc., and contact with chemical substances such as chlorine bleach, and especially excellent light resistance. In the polyurethane fiber of the present invention, since the hindered amine compound is chemically bonded to the polyurethane, blooming of the light resistance stabilizer to the surface of the polyurethane fiber, melt spinning or dissolution of the light resistance stabilizer in the polyurethane stock solution, etc. Therefore, there is no trouble in the fiberizing process, and the light resistance is not lost even by washing with water or dry cleaning. Furthermore, the polyurethane fiber of the present invention has a hindered piperidine ring pendantly bonded to the polyurethane soft segment as a side chain, and therefore has a high degree of polymerization of polyurethane and has physical properties such as elastic recovery, tensile strength, and heat resistance. Excellent in

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tatsuya Oshita 1621 Sakata, Kurashiki City, Okayama Prefecture Kuraray Co., Ltd.

Claims (1)

[Claims] 1. A fiber comprising a polyurethane produced by using a polymeric diol, an organic diisocyanate, and optionally a chain extender, wherein the polyurethane is at least part of the organic diisocyanate in the 2- and 6-positions. A prepolymer-type organic compound having a piperidine ring-containing group in which each position is substituted with two alkyl groups in a pendant side chain, having an average molecular weight of 1500 or more and an average number of isocyanate groups of 1.8 to 3 A polyurethane fiber produced by using a polyisocyanate.