KR820001464B1 - Process for preparing hydrophilic polyester fibers - Google Patents

Abstract

A fibre having a stable pore system capable of capillary condensation at 20≰C and RH less than 97 % has a moisture absorption capacity greater than 2 % by weight at 40≰C and 92 % RH and at least 25 % moisture absorption induced by capillary condensation is formed by spinning a polyester composition containing from 1 to 20 % by weight, of one or more oxalato complexes.

Description

Process for producing hydrophilic polyester fiber

The present invention relates to a process for producing hydrophilic polyester fibers.

As is known in the art, the final analytical crystals of the fibers which are health-friendly and comfortable to wear when worn are almost dependent on thermal conductivity and wettability. Natural fibers are hydrophilic. That is, natural fibers absorb a significant amount of wetting from the air and also have high absorption and large moisture retention. However, compared to polyester fibers, these natural fibers have a drawback when sweating because the human body needs to dissipate significant amounts of heat. For example, when oleic and polyester fibers swell, the cross-section of the oleene fibers increases by about 25% while the polyester fibers increase by only 1% (Robinson, Textilpraxis International 1976, page 1180). This, in particular in the case of dense fibers, impedes the passage of air and thus impedes the conduction of wetting directly through the fibers. In addition, a considerable amount of incidental heat is absorbed by wool [1 13 J / g water (27 cal / g water)] than when water is absorbed into polyester [3.35 J / g water (0.8 cal / g water)]. Occurs when there is a problem [Robinson, Textilveredlung, 1977, page 264]. Wool's capacity for absorption clearly disappears when temperature rise is closely related to thermal effects. Moreover, fibers made of polyester dry more easily than fibers made of wool. The advantage of polyester in this respect is mainly the fact that the polyester absorbs extremely small amounts of water. On the other hand, low performance on water absorption when wearing garments made of polyester fibers results in poor health and undesirable comfort.

Therefore, it is necessary to eliminate the difficult difficulties described above without compromising the excellent properties of the polyester. That is, it is desired to increase the wet absorption and water retention on the basis of the hydrophilic property (specified in Robinson).

Among other things, attempts have been made to improve hydrophilic properties by all polymers or the surface of fibers or by chemical modifications thereof. However, no significant achievements have been made so far. This is very beneficial to physically modify the basic fiber structure (eg by increasing the absorbent surface of the fiber).

For example, the basic fiber structure of this type is known in the case of polyacrylic fibers (Melliand Textilberichte 1/1977, pages 11 and 12). Polyacrylonitrile fibers consist of a seam with a fairly large number of good capillaries and a dense sheath with a number of good vasculatures that move water into the fiber's aperture from the surface. This envelope is obliged to ensure the protection and processing of the internal caliber without problems.

In the method described in JP-A-2,554,124, this type of hydrophilic polyacrylonitrile fiber has a higher boiling point than a commercially available spinning solvent based on a solvent and a solid base, and is applied to both the spinning solvent and water. 5 to 50% by weight of a liquid which is readily miscible and which represents a nonsolvent in the spun polymer is added to a spinning solvent [e.g., dimethyl acetamide, dimethyl sulfoxide, methyl pyrrolidone or dimethylformamide] Obtained by spinning. Examples of such liquids are as follows. Alkyl ethers and alkyl esters of polyhydric and colloids, high boiling alcohols, esters or ketones, preferably glycerin.

The filaments obtainable in this way are seam-blood structure, average cardiac diameter of 500 to 1000 nm (5000 to 10,000 A °), wet absorption of 2 to 5% (65% relative humidity, 21 ° C.) and 10 to 30%. It has a caliber with moisture retention.

Dry-wet spun-sea fibers obtained from acrylonitrile polymers having a wet absorption of at least 7% (relative humidity 65%, 21 ° C.) and a water retention of at least 25% are described in JP-A-2,607,071. .

This fiber contains a carboxyl group from a solvent added 5 to 50% by weight of a compound having a higher boiling point than that of the spinning solvent, which is miscible in both water and the spinning solvent and which does not dissolve the copolymer. Prepared by spinning an acrylonitrile polymer, the compound added on the cleanly spun filament is continually washed and then all or part of the carboxyl group is converted to salt form.

Modifications of this type known to polyacrylonitrile are not commonly used to improve the hydrophilic properties of the main polyesters. In practice, polyacrylonitrile is dry spinning, that is to say it is dry spinning at relatively low temperatures from organic solvents.

Polyesters, on the other hand, are commonly spun from the melt at about 300 ° C. In addition, unmodified polyacrylonitrile has a relatively high wetting capacity of about 1.5%. On the other hand, unmodified polyesters have an almost low wet absorption of only 0.3 to 0.6%.

It is also a polyester fiber with a large number of apertures produced by special drawing methods or by foam using an inert gas. Like the polyacrylonitrile fibers described above, these polyester fibers contain large cavities that can be detected by simple microscopy, but these cavities do not significantly increase wet absorption. HD Weigmann et al (Melliand Textilberichte 6/1976, Page 470-473) treat polyester fibers with dimethylformamide and subsequently remove them from the solvent in boiling water, dry them and then increase the speed of dyeing and relative dye absorption. These are heat treated in order.

This method results mainly in structural changes, such as being oriented in an amorphous band. This is caused by the interaction between the polymer and the solvent, rather than the strong second crystallization reaction, and also inducing the formation of crystals in the swollen fiber structure occurs with the temperature of the solvent treatment. The stability of the swollen fibrous structure prevents them from breaking completely upon removal of the solvent and also leads to the formation of cavities or micropores, according to the inventors.

The properties of these products are described in more detail below, but they can be expected to have a relatively small pore volume and consequently low water absorption and water retention. Apart from this, the effect is stable and also causes a severe decrease in the relative absorption of the dyes even at heat treatments above 120 ° C., resulting in total destruction of the pore system occurring at temperatures between 180 and 200 ° C.

The present invention is capable of capillary condensation at a relative humidity of 20 ° C. and 97% or less, and also has a wet absorption capacity of 2% by weight or more at a relative humidity of 40 ° C. and 92%, and the ratio of wet absorption induced by capillary condensation is A hydrophilic polyester fiber having a stable pore system that is at least 25% is provided.

As used herein, "polyester" means inclusive of both homo- and copolyesters. Examples of such polyesters may be obtained from one or more of the following acids or ester forming derivatives thereof and one or more dihydric or more polyhydric aliphatic, alicyclic, aromatic or araliphatic alcohols or bisphenols There are things. Examples of such acids include adipic acid, pimeline acid, seberic acid, azelaic acid, sebacic acid, nonane, decane or undecane dicarboxylic acid, optionally alkyl- or halogen-substituted terephthalin and isophthalic acid, nitro- Substituted terephthalic acid, 4,4'-diphenylether, thioethersulfone or alkylene dicarboxylic acid, naphthalin-2,6-dicarboxylic acid and cyclohexane-1,4- and -1,3-dicarboxyl It's Rixan.

Typical diols and phenols suitable for the production of these homo- and copolyesters are ethylene glycol, diethylene glycol, 1,2- or 1,3-propane diol, 1,4-butanediol, 1,6-hexanediol, 1 , 8-octanediol, 1,10-decanediol, 2,2-dimethyl-1,3-propanediol, 2,2,4-trimethyl hexane diol, p-xylene diol, 1,4-cyclohexanediol, 1 , 4-cyclohexane dimethanol, bisphenol A and the like. Homo- and copolyesters or terephthalinic acid are preferred, with polyethylene terephthalate being particularly preferred.

The polyester fibers according to the invention have micropores of considerable size that are stable and easily wettable to the extent that the micropores are open, ie correlated with the fiber surface. As used herein, "microcaliber" is not used academically. Here, the micropores refer to the pores having a radius of 30 nm (300 A °) or less. Compared to micropores having a radius (<) larger than the radius of 30 nm, this cannot be detected by a simple microscope, but only by a special method using an electron microscope. Suitable for special methods are capillary condensation, X-ray diffraction, Mercury porous magnets and density measurements placed on the microscope.

Capillary condensation is a very important measurement for the sphere system of the present invention. At the same time, this is based on the practical use of spheres (especially spheres in clothing).

According to Helmholtz-Thomson's law, it is known that capillary condensation starts with a wet liquid in the capillary with a radius of curvature r when the partial pressure of the liquid vapor is greater than pr.

Where pr represents the increasing pressure on the radius r of the curved surface,

p∞ represents the vapor pressure on the flat surface,

M, δ, ρ represent the molecular weight, surface tension and density of the liquid, respectively.

R represents a gas constant; And

T represents absolute temperature.

Numerically, capillary condensation of water at 20 ° C. begins when the capillary radius r specified below falls below the relative humidity (rel. H) specified below and is fully wettable.

Thus, a capillary with a radius of 10 nm (100 A °) or smaller is required to achieve capillary condensation at 90% relative humidity. The general formula given above is modified in the following way when the wet is not the ideal (wet angle β greater than 0 °);

In this case, a correspondingly small radius is necessary to achieve capillary condensation. For example, in the case of unmodified polyester and water, the wetting angle is about 80 ° [T. H. Grindstaff Text, Res. J. (1969), page 959, therefore Cos β is 0.2. As a result, capillary condensation only occurs in the case of undeformed wettability when the radius of the aperture is five times smaller than the specified value. It is a liquid that is not wet at all (β = 90 ° or 90 ° ≦ β ≦ 180 °) and there is no capillary condensation. Capillary condensation is the first intentional use of the present invention to improve the hydrophilic properties of synthetic fibers. Apart from a significant amount of absorption, other obvious effects of increasing absorption at elevated temperatures (e.g., a high percentage of absorption, no swelling, almost no "dry" feeling and no unnecessary thermal effects) are commonly used absorption. This is achieved in comparison with the action (for example the formation of hydrates).

Capillary condensation is described in the book of Physics and Physics [e.g., R. Brdicka, Grundlagen der physikalishen chemie, I 1 edtion, pages 551-553, VED Deutscher Verlag der Wilssenschaften, Berlin, 1972, H. Franke, Lexikor der physik, 3rd edition, pages 776-779, Frankh'sche Verlagshandlung stutlgart and to E. Manegold, kapkllarsysteme, Volume I (Trundlagen) 1955, Straβenbau, chemie und Technik Verlagsgesellschaft mbh, Heidelberg.]

Microcavities can also be detected by the mechanism of small angle dispersion of successive X-rays. Dispersed small angle reflections are normally used to represent synthetic fibers by small angle dispersion of X-rays. This reflection is used because of the periodic change of crystal and hole area in the sample. Advantageous forms or four-point forms are obtained according to the mutual arrangement of these regions. Moreover, polyester fibers with regions of aperiodic cyclic arrangements of different electrode densities reflect small scattered dispersions to create more continuous small angle dispersions. If there are cavities with areas of aperiodic arrangement of different electrode densities, the indicated small angle variances are obtained (references are made below to describe in more detail). The hydrophilic polyester fibers according to the invention exhibit the indicated continuous small angular dispersions of this form.

The pore system of the hydrophilic polyester fibers of the present invention can be made clear by quantitative analysis of small angle dispersions. Isotropic small angle dispersions are obtained in the case of spherical micro-cavities. The radius of these spherical cavities can be determined from the independence of the angle depending on the strength of the successive small angle dispersions. In the case of non-spherical micro-cavities having a preferred orientation in the sample, it is possible to obtain anisotropic small angle dispersion and also to clearly impart the orientation of these cavities from the anisotropic material to the sample. The lateral diameter of the non-caliber cavity can also be determined from the independence of the angle depending on the strength of the continuous small angle dispersion. If compared to several samples with smaller cavities, the number of cavities relative to the sample is obtained from successive small angular dispersions.

For this theory, variance measurement and analysis of X-ray small angles, references are described in the following bibliography (see, for example, Zahn and Winter, Kolloid-Zeitschrift 128 (1952), pages 142-153; H. Kiessing, Kolloid 152 (1957), pages 62-74; Q. Kratky Anglur Chemie 72 (1960), pp. 467-482, V. Hochmann, Faserforschung and Texiltechnik 27 (1976), No. 8; Zeltschrift fut Polymer forschung, Pages 417-424; A, Guinier X-ray diffraction, H. W. Freeman and Company, San Francisco, 1963.

Another property of the polyester fiber of the present invention is the pore volume as a function of the radius of aperture. This can be determined very easily using Mercury porous magnetism. Since the pores having a radius of 5 to 50,000 nm are detected by this method, therefore, there are micropores and large pores.

References to this theory, the analysis of the Mercury porous magnets, are described in the following text. See, eg, H. Juntgen and M. Schwuger, Chem Ing. -Techn., 38 (1966), Pages 1271-1278 and E. F. Wagner, Chemiefasern 8-67 (1967), Pages 601-606.

Density can also be measured or to demonstrate the pore system. If the pore system is present in the sample, the density value is much smaller than the density of the corresponding unmodified non-porous polymer, since the component solution cannot be externally enclosed or the pore wall can be wetted by the component solution. It is obtained during the usual measurement of the density in a component liquid consisting of carbon tetrachloride and heptane under conditions that cannot penetrate. The pore volume of the pores that do not appear through the microscope is obtained after removing the pore volume determined by the microscopic measurement.

Four measurement methods, namely, small-angle dispersion of X-rays, mercury porosity magnetism, capillary condensation (absorption isotherms), and density measurements are used to provide a large sized pore system in which the fibers of the present invention are easily accessible to the outside and easily wetted by water. It can be seen that it is clearly demonstrated that their pore radius is smaller than nearly 30 nm.

Permanent hydrophilic properties are also another property of the polyester fibers of the present invention. The pore system is described as "stability" in the context of the present invention when at least constant when washed and subsequently dried in air at 100 ° C. This stability is at least necessary. The pore system of the fibers of the present invention is substantially more stable.

This includes processing, hot air fixation (eg for 1 minute at 190 ° C.), hot wash and drying as well (eg for 1 hour at 120 ° C.), and hot air drying for 3 minutes at 100 ° C. as well. It is stable under conditions of washing (for example, in the presence of 5 g of detergent per liter and for 60 minutes at 100 ° C. under dry cleaning). The hydrophilic nature of the polyester fibers of the invention caused by the pore system is stable, ie it remains almost unchanged. Following the measurements described above, the polyester fibers of the present invention are described below by means of their pore systems and also by their hydrophilic properties.

As mentioned above, the polyester fibers of the present invention absorb at least 2% by weight of wet at 40 ° C. and 92% relative humidity. The overall wet absorbency of the hydrophilic polyesters of the present invention consists almost exclusively of the wet absorbency induced by capillary condensation and about 0.5% of conventional wet absorption for unmodified polyesters.

The percentage of wet absorption capacity caused by capillary condensation is at least 25% of the total wet absorption capacity, thus it is relatively small when the total wet absorption capacity is low (e.g. 25%) and also relatively high when the overall wet absorption capacity is high (e.g. , 95%). About 70% of the total wet absorption is desirable.

The hydrophilic polyester fibers of the present invention have a wet absorption of up to 25% by weight at 40 ° C. and 92% relative humidity. Preference is given to polyesters having a wet absorption of 5 to 15% by weight. This type of product can perform the process without difficulty and also yields excellent fiber.

Polyester fibers of the invention having a wet absorption of 15 to 25% by weight at 40 ° C. and 92% relative humidity are produced without extremely difficult difficulties (especially in complex cases). However, because of their high porosity, polyester fibers have a low strength.

Solid density of the fibers is 1350kg / cm ³ (preferably from 1050 to 1150kg / cm ^3).

The pore system of the polyester fiber of the present invention is preferably composed of micropores and large pores. Micropores have a radius of 30 nm or less (preferably 5 to 15 nm) and large pores have a radius of 100 to 3000 nm. Micropores have a volume of at least 0.04 cm / g.

The fibers of the present invention have a pore radius of 5 to 15 nm and a pore volume of 0.04 to 0.15 cm ³ / g. Large pores have a volume of 0.01 to 0.10 cm ³ / g. Products with even higher pore amounts up to 0.5 cm ³ / g can also be prepared. This can be considered for these uses in the absence of fiber strength or only in some areas.

Both micropores and large pores of the polyester fibers of the invention are open, ie they are in communication with the surface of the fiber.

The polyester fibers of the present invention preferably have aspherical mesoporees, the vertical cross section of which is a plurality of transverse areas. Most of these non-spherical pores are oriented parallel to the fiber axis.

It is a property of the polyester fibers of the present invention that the walls of the pore system are easily wetted with water. A specially structured pore wall, such as a pore system, causes the hydrophilic properties of the polyester fibers of the present invention to occur.

The product of the present invention has a significantly higher wet absorbency compared to conventional polyesters. The following table shows the polyethylene terephthalate fibers according to the invention made using conventional polyethylene terephthalate fibers, 10% weight potassium aluminum oxalate [K ₃ [Al (C ₂ O ₄ ) ₃ ]). It is a value for. Measurements are made at DIN 54 at constant 20 ° C / 65% relative humidity (standard condition by DIN 50 014), 20 ° C / 92%, 34 ° C / 92% and 40 ° C / 92% (moisture and warming by DIN 50 015). It was taken as 201.

Wet Absorption (% by weight)

The table is described as follows. Under the conditions given, the polyester fibers of the present invention absorb substantially more wetting than conventional polyester fibers at standard temperatures of 20 ° C./65% and at higher temperatures and higher relative humidity. Absolute wet absorption is no better than the difference in wet absorption of 20 ° C./65% and constant condition 34 ° C./92% for health care garments. Certain conditions at 34 ° C./92% correspond to conditions close to the skin at the upper limit of a comfortable range and the difference in moisture absorption consequently corresponds to the performance of the fiber to absorb moisture during wear at the lower limit of the comfortable range. This difference is only 0.2% for conventional polyethylene terephthalate but 7.0% for the hydrophilic polyester fibers of the present invention. The value thus obtained is as high as in the case of wool. Unlike hydrophilic polyester fibers, the absorption of wool decreases with temperature.

This effect impairs the comfort of the fabric in clothing because the fiber must absorb a lot of moisture and there is no wetting as the skin temperature rises, and thus sweating increases.

Another major property of the fibers of the invention is their high water retention. In comparison with the wet absorption capacity determined by the micropore system, the water retention depends on both the micropores and the structure of the large pores. Moisture retention is usually determined by DIN 53 814. Any amount of material tested is completely filled with water using a humectant and then centrifuged with a centrifuge under clearly specified conditions. Weigh the centrifuged sample, dry and reweigh. The difference between the two weights is the water remaining after centrifugation of the sample. In general, conventional polyesters have a moisture retention of 2 to 5% and the fibers of the invention have a moisture retention of at least 10%, preferably 10 to 50%, more preferably 20 to 30%, and known poly The ester has a water retention of about 8.5% due to structural modifications due to the solvent. Water retention is also very important for the usefulness of the fibers. Since cotton and wool have a moisture retention of 40-50%, the fibers of the invention in this respect achieve the properties of natural fibers. It should be noted that cotton and wool already absorb 8 to 15% moisture during storage.

Reducing wet touch is another property of textiles that gives comfort to clothing. This is the amount of wetness (in%) at which the textile sample can feel the dampness. Two methods have been applied to reduce the wet feel. On the other hand, dried fibrous samples (eg flat knits) are used as starting materials and are exposed to increased wet conditions. On the other hand, a wet fibrous sample is used as a starting material and then dried in standard condition (20 ° C./65%) according to the method for determining the moisture retention (DIN 53814). In all of these cases, it was decided that at least four people would not wear underwear made of knit fabric or should dry the underwear directly because the fabric is too wet. The wet touch was limited to about 0.4% for conventional polyester, about 19% for wool and about 8% for cotton. The fibers of the present invention limited the wet feel to 7-11%. Fibers made from unmodified polyester absorb only about 0.1% by weight of moisture after storage in standard condition. Fibers made from wool absorb about 4% by weight of wet under the conditions described above, while the polyester fibers of the present invention absorb about 8% by weight of wet.

In addition, the fibers of the present invention have excellent properties for wet divergence. Wet divergence is characterized by the progression of wet divergence of samples that have been previously moistened to DIN 53 184 at standard temperature 20 ° C / 65%. The cycle of time is particularly beneficial until the limit of wet touch is achieved. The period of time is 1: 2 in the case of conventional polyethylene terephthalate, the hydrophilic polyester of the present invention, wool and cotton; 2.5: 3 ratio. This indicates that the hydrophilic polyesters of the invention dry faster than wool or cotton.

In addition to the hydrophilic properties mentioned above, the fibers of the invention have very excellent properties when measured in comparison with polyesters. The fibers of the present invention can be prepared with conventional fineness and have the following fibrous properties.

In addition, the affinity of the inventive fibers for dyeing is very good. The dyeing-rate absorbing power of the polyester fiber of this invention absorbs much higher than normal polyester fiber. The amount of dye required to achieve a given color is greater in the case of the hydrophilic polyester fibers of the present invention and in the case of known large pore polyesters than in the case of the conventional forms of polyester fibers.

The present invention spins a polyester composition containing 1 to 20% by weight of one or more oxaleto complex compounds corresponding to the following general formula, elongates the resulting filaments and produces 90 ° to 170 filaments in the presence of water. Also provided is a method of making the hydrophilic polyester fibers of the present invention characterized by hydrofixing at &lt; RTI ID = 0.0 &gt;

M _n [Z (C ₂ O ₄ ) _m ]

In the above formula

M represents one or more of the following ions:

Li, Na, k, R _b , Cs or NH ₄ ;

Z is Mg, Ca, Sr, Ba, Zr, H _f , C _e , V, C _r , M _n , F _e , C _o , N _i , C _u , Z _n , C _d , B, Al, G _a , At least one complex forming core atom selected from In, S _n , P _b and S _b ,

1,

2,

3 또는

3를 나타내며; 및n is

One,

2,

3 or

3; And

2,

3, 또는

4를 나타낸다 :m is

2,

3, or

Indicates 4:

Polyesters which are necessary for the process of the invention and which contain one or more oxaletto complexes are described in the patent application of the Federal Republic of Germany P2628964. It is described in detail in 5-43. It is prepared by injecting one or more oxaleto complex compounds into the polyester composition in a conventional manner. For example, the oxaleto complex may be added to the polyester starting material during the transesterification or polycondensation and thus is homogeneously dispersed in the formed polyester. Another way of matching this is to melt the polyester composition, mix it with the oxaleto complex and then process it in granule form to form the polyester directly. Another method is to powder the finely separated oxaleto complex on the polymer granules and to carry out the process with the polymer granules.

Oxaletto complexes and their preparation are described in the following references: KV Krishamurty and GM Harris in Chemical Reviews, Vol. 1 (1961), P. 213-246. Generally, the number of ligands is 1,2,3 or 4, the charge of the complex anion is -1, -2, -3, -4 or -5 and the number of central atoms is 1. Here the number of ligands and the charge of the complex anion are determined by the isotope of the central atom and the charge. In the context of the present _{invention, [Z (C 2 O 4} ) m] - e in the form of oxalate retrograde complex containing a complex anion is m and the integer is different as compounds and as having the exact composition as quantitative ^{analytical-of} e It is a compound having a value. This is the case, for example, when oxaletto ligands are replaced in small amounts by other ligands. Compounds of this type can be prepared by injecting or exchanging an external ligand into the complex anion during or after the synthesis of the oxaleto complex. Such is used in the central atom, for example, oxaletto complexes having cation constructs that are not strictly quantitatively constructed are within the background of the present invention. The number of central atoms is also different from integers in this case. This may be the case when a small amount of a central atom is replaced by another central atom having a different isotope or other valence. Such deflections are often known to occur in complexes and are also well known to those skilled in the art.

The polyester composition used in the method of the present invention may also contain mixed oxaletto complexes having appropriate amounts of other central atoms in place of one central atom of the quantitative amount. The polyester composition may also explicitly contain various types of mixtures or mixed oxaleto complexes.

이라는 것을 정의하는데 사용되어 왔다.Because the values for e, n and m are different from integers

Has been used to define

Since the values of e, n and m are different from integers, the sign is used to describe the following. Polyesters containing oxaleto complexes having one or more central atoms selected from those described below are very preferably used in the process of the invention [M _g , B _a , Z _r , F _e , C _o , C _u , Z _n , A _l , S _n , C _r , and S _b .] Preferred polyesters contain alkali metal aluminum oxalteto complexes corresponding to one of the following general formulas: M ₃ [Al (C ₂ O ₄ ) ₃ ] or M [Al (C ₂ O ₄ ) ₂ ], in particular K ₃ [Al (C ₂ O ₄ ) ₃ ] or oxalteto complex: K ₄ [Zn (C ₂ O ₄ ) ₃ ], K ₄ [ Zr (C ₂ O ₄ ) ₄ ) ₄ ], K ₃ [Cr (C ₂ O ₄ ) ₃ ], K ₃ [Fe (C ₂ O ₄ ) ₃ ], K ₃ [Sb (C ₂ O ₄ ) ₃ ] , K ₂ [Mg (C ₂ O ₄ ) ₂ ], K ₂ [Fe (C ₂ O ₄ ) ₂ ], K ₂ [Zn (C ₂ O ₄ ) ₂ ] or K ₂ [Cu (C ₂ O ₄ ) ₂ ].

The compound is lithium, sodium, potassium, rubidium, cashium, ammonium-aluminum dioxaletto or aluminum trioxalate salt containing 4 or 6 valence aluminum atoms. These are known or can be obtained by simple methods by precipitation from the components of the aqueous solution. For example, the aluminum sulphate solution can be obtained by reacting with lithium, sodium, posium, rubidinium, cashium or ammonium oxaletto solution.

The preparation and properties of these complex salts are described in the literature [Gmelins Handbuch der Anorganishen Chemie, 8th edition, "Aluminum", Part B, issue 1, Verlag Chemie GmbH Weinheim / Bergstr. 1933]

Another method that may be suitable for the preparation of the potassium-aluminum trioxalate salts is described in the literature. [Inorganic Synthesis, Volume 1, McGraw Hill Book Comp., Inc., New York and London 1939, Page 36] The method described in the above document provides a purely precipitated aluminum hydroxide solution with an aqueous solution of potassium hydrogen oxalate. That's how it's handled.

Most of the compounds used according to the invention are known by analysis as oxaleto complexes containing the other central atoms described above. These compounds are obtained by reacting a salt of a central atom with an alkali metal oxalate. Suitable compounds having a central atom are sulfuric acid, hydrochloric acid, hydroxides, acetates, carbonates and oxalates.

The preparation of this complex is described in detail in the literature [D. P. Graddon, J. Jnorg, & Nucl. Chem. 1956, Vol. 3 pages 308-322 Bailar et al Jnorg Syntheses, Vol. 1 page 36 K. V. krisbnamurty et al., Chem. Rev. 61 (1961), pages 213-246

Methods for preparing oxaleto complexes are described in detail in the cited publications or prepared by analogous methods. Melt spinning and stretching of the polyester containing the oxaleto complex compound used in the method of the present invention are carried out under conventional conditions by a conventional apparatus.

Polyesters achieve the grade and stability of hydrophilic properties in the process of the present invention as a result of hydrofixing under predetermined conditions. The hydrofixing treatment is carried out at a temperature of 90 to 170 캜, preferably 120 to 140 캜 in the presence of liquid water.

The basis of the present invention is that the fibers are not exposed, whether hot air treatment (eg, stability, hot air fixation or processing) of 120 ° C. or higher, or temperature washed below 90 ° C. and then hot air dried prior to hydrofixing.

The products subjected to the above-mentioned hot air treatment or washing without hydrofixing according to the present invention have a wet absorption which is clearly lower or about 1/3 lower than that of the product of the present invention. This is used for moisture retention. The products previously exposed to the above-mentioned hot air treatment or washing and subsequently hydrofixed have only fine hydrophilic properties. This refers to the fact that the operation of hydrofixing (ie, continuous stretching), hydrofixing and conventional heat treatment are important.

Hydrofixing temperature has an important effect on the hydrophilic nature of the polyesters of the present invention. As the hydrofixing temperature increases, both wet absorption and moisture retention increase. When hydrofixing is carried out at a temperature of 90 ° C. or lower, the product has a small moisture retention of the same degree as the relatively low wet hygroscopicity. The persistence of hydrofixing lasting a few minutes to half an hour and the method of shrinking the fibers during the fixing process do not have a significant effect on the wet absorption of the product of the present invention. That is, the fibers of the invention can be fixed both without tension (e.g. to staple fibers or filaments of continuous non-stressed) and under tension (e.g. to bobbins) below shrinkage tension. However, the water retention and volume of large pores will be clearly affected. When the fiber shrinks freely, a higher value is obtained compared to performing a hydrofixing process under shrinkage.

It is fundamental to the present invention that the hydrofixing process is carried out at a given temperature in the presence of liquid water. In this method, it is necessary to contact the liquid to be hydrofixed with liquid. The amount of the liquid water is preferably 100% by weight or more based on the material to be hydrofixed. Caution should be given to water as much as possible. Water may be used, for example by immersing the substance in water and then continuing to drop water onto the substance or spray it onto the substance.

A medium consisting solely of water is not necessary for hydrofixing. It may also contain adducts (e.g., water soluble salts or liquids that are susceptible to miscibility with water) in fine or large quantities. Additives causing the boiling point of water are used, for example, to carry out hydrofixing at the lower pressures and under the required temperature conditions. This is particularly beneficial for hydrofixing during hot dyeing or for bleaching performed under given conditions. However, as mentioned above, since the result of poor wet absorption and water retention results in hot air treatment of more than 120 ℃ and cleaning below 90 ℃ should be avoided.

It is also possible to use bicomponent polyester fibers instead of homo- or copolyester fibers made of a single fraction. In this case, the blood and seam of the fibers may contain other polyester bases and / or other oxaleto complexes and / or other amounts. However, this type of bicomponent fiber comprises shims composed of modified polyesters containing oxaleto complexes and blood (for example polyethylene terephthalate) composed of unmodified polyesters. When this type of bicomponent fiber is carried out by the method of the present invention, the fiber according to the present invention is obtained. It is surprising that this is obtained only when the blood consists of unmodified polyester. The products obtainable in this way are distinguished by the fact that they have the same feel as their externally flat and conventional forms of polyester.

This represents the desired properties of natural fibers in addition to the advantages of conventional polyester fibers and it is now possible to produce new types of polyester fibers by the process of the invention which have very good properties for several points. It should be borne in mind that this property is retained during normal use and during use.

The hydrophilic polyester fiber of the present invention exhibits excellent properties of usability. Compared with conventional forms of polyester, they have very good hydrophilic properties, in particular distinguished by high wet / hygroscopicity, high limiting wet touch and moisture retention. Wet absorption by capillary condensation occurs without the heat of hydration. Wool and cotton, on the other hand, also absorb moisture by hydration, which is consistent with absolute thermal effects. The sweating caused by the heat of hydration of wool or cotton occurs when the body temperature is relatively high and thus sweating occurs. As mentioned above, the polyester fiber of the present invention absorbs the amount of increase in the wet as the temperature rises, and thus, it is more useful than wool and cotton, and it can be referred to as a high-speed wet absorption, and that the hydrophilic polyester fiber of the present invention The result is that it does not swell. This is felt decisively when the fiber is dried.

The present invention is described in detail by the following examples.

[Examples 1 to 4]

Examples 1 and 2:

Production method of polyethylene terephthalate fiber according to the present invention

(a) Preparation and Milling of Oxaletto Complex

K ₃ [Al (C ₂ O ₄ ) ₃ ] is prepared by the method described in the literature. Inorganic Synthes isl (1939) page 36 by JC Ba. Iar and EM Jones] The obtained complex salts are continuously dehydrated at 150 ° C. and about 10 Torr for 15 hours. Analysis of samples obtained with different mixtures is between K _{2 · 87} [Al (C ₂ O ₄ ) _{3 · 02} ] and K _{3 · 36} [Al (C ₂ O ₄ ) _{3 · 46} ].

After grinding, 200 g of dehydrated complex salt in a bead mill (PMI Model made by Draiswerke, Mannheim, Germany) containing 410 g of quartz beads having a diameter of 1 to 3 mm was ground with 400 g of ethylene glycol and the largest complex in dispersion. While the salt particles have a diameter of about 4 μm, most of the particles are about 1 μm in size.

The quartz beads are separated by filtration through a shaker and then rinsed with 200 ml of ethylene glycol and the dispersion is diluted with a rinse solution. Particles larger than 2 μm are separated by leaving the dispersion for 72 hours in a vessel.

(b) polycondensation

600 g and 300 g of the dilute solution having 150 g and 75 g of K ₃ [Al (C ₂ O ₄ ) ₃ ], respectively, were added at 13.50 g of dimethyl terephthalate and 1200 g of methylene glycol at a stirring speed of 30 revolutions per minute and a temperature of about 245 ° C. Is transferred into the polycondensation vessel together with the product of transesterification from and 150 ppm zinc acetate is used as catalyst for transesterification and 200 ppm antimony trioxide is used as condensation catalyst. Distilled ethylene glycol can be reused for condensation without purification. The polycondensate contains 10 (Example 1) or 5 (Example 2) wt% K ₃ [Al (C ₂ O ₄ ) ₃ ].

(C) shape

The polycondensate obtained is threaded in the usual manner and dehydrated at 125 ° C. and 60 Torr for 24 hours. The threads or chips are spun at 296 ° C. (the highest spinning temperature) to form filament yarns with individual fineness of 3.0 dtex and total fineness of 150 dtexf 48. The filament yarns are stretched at a ratio of 1: 4.2 and continuously burned. The textile data of the materials obtained for resistance to sunlight, light fastness and solution viscosity correspond almost to those of conventional polyethylene terephthalate and can be obtained under the above-mentioned conditions without addition of oxaleto complex.

(d) hydrofixing

About 15 g of the material or knitted fabric prepared therefrom and 200 ml of water are in each case injected into a Linitest instrument preheated to 140 ° C. in a 270 ml large pressure resistant vessel. After 15 minutes, the vessel is removed again and cooled to 60-80 ° C. for 5 minutes by means of a water bleeding instrument. The fibers were rinsed with brine and pre-dried in a circulating air drying cabinet at 100 ° C. for 1 hour and then dried at constant temperature for 4 hours at 120 ° C. and 1.5 mb (20 ports).

Example 3

Preparation of Unmodified Polyethylene Terephthalate Fiber (Control Example)

Unmodified polyethylene terephthalate fibers are used for control purposes. Polycondensation and shape are performed by the method described in Example 1 (b) and (c), respectively.

Example 4

Preparation of Polyethylene Terephthalate Modified by Dimethylformamide (Control Example)

Polyethylene terephthalate fibers modified by treatment with dimethylformamide by the method described by H. D. Weigmann et al (loc. Cit) are also used for control purposes. The sample is treated with dimethylformamide for 2 minutes at 140 ° C. without tension, then removed from the solvent with water (15 minutes at 100 ° C.) and dried in air. We do not specify a drying temperature but the material is dried at (a) 20 ° C and (b) 100 ° C.

The porosity and hydrophilic properties of the fibers according to the invention described above are described in the following table (Table 1) and also inserted for the control fibers exemplified above.

The measurement method is illustrated as important in Table 1 below. Reference is made to the specification and literature, and all methods of performing these measurement methods are described by standard values.

TABLE 1

Example 5-15

The following examples relate to the preparation of copolyester fibers from hydrophilic polyethylene terephthalate fibers, polybutylene terephthalate fibers and terephthalic acid / adipic acid, such as terephthalic acid / isophthalic acid and ethylene glycol, terephthalic acid / azeric acid . Elongation also uses flat knit fabrics composed of homo- or co-polyester filaments. Hydrofixing is performed in the instrument at 140 ° C. for 15 minutes. The homo- and co-polyester compositions used are illustrated in Table 2 below. This is the same as their content in the polymer composition, the polymer, the oxaleto complex and the wet absorption capacity measured at 40 ° C. and 92% humidity. The wet absorbency of the unmodified polyethylene terephthalate fibers and the unmodified copolyester fibers composed of terephthalic acid, azelinic acid and ethylene glycol were given in contrast.

TABLE 2

Claims (1)

Spinning a polyester composition containing 1 to 20% by weight of at least one oxaletto complex corresponding to the following general formula, elongating the resulting filament, hydrofixing the produced filament in the presence of water to 90 to 170 ℃ Process for producing hydrophilic polyester fiber characterized in that (hydrofixing) M _n (Z (C ₂ O ₄ ) _m ] Wherein M represents one or more of the following ions, (L _i , N _a , K, R _b , C _s or NH ₄ ) Z is M _g , C _a , S _r , B _a , Z _r , H _f , C _e , V, C _r , M _n , F _e , C _o , N _i , C _u , Z _n , C _d , B At least one complex forming center atom selected from Al, G _a , In, S _n , P _b and S _b , where n is

One,

2,

3, or

4, m is

2,

3, or

4 is shown.