JPH11350252A - Easily dyeable polyester fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an easily dyeable polyester fiber capable of being dyed in a deep color at a normal temperature and excellent in light fastness by forming a fiber of a polyalkylene terephthalate containing a polyalkylene glycol and cerium oxide fine particles. SOLUTION: This easily dyeable polyester fiber is prepared by melt-spinning and stretching a polyalkylene terephthalate, e.g. a polyethylene terephthalate containing 2-10 wt.% polyalkylene glycol having 400-2,000 average molecular weight, e.g. a polyethylene glycol and 0.05-5 wt.% cerium oxide particles having <=3.0 μm mean particle diameter obtained by coating the surface of a mixture of cerium oxide with a talc or a silica in (15:85)-(50:50) weight ratio with an amorphous silica to obtain the easily dyeable polyester fiber having 60-90 deg.C temperature of showing a maximum value of a dynamic loss tangent at 10 Hz measuring frequency, <=5 difference in black color brightness by dyeing at 80 deg.C and 130 deg.C, and >=85% maintaining rate of the black color brightness after a light fastness testing by a carbon fade irradiation for 20 hr.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an easily dyeable polyester fiber which can be dyed in a dark color at normal pressure, has little fading due to light after dyeing, and has excellent light resistance.

[0002]

2. Description of the Related Art Polyester fibers, especially those containing polyethylene terephthalate (PET) as a main component, have high crystallinity and a high softening point, so that not only mechanical properties such as strength and elongation, but also heat resistance and heat resistance are obtained. It exhibits excellent properties such as chemical properties and is widely used in the field of industrial materials and clothing.
However, it also has disadvantages such as being difficult to be dyed in a dark color, easily causing pilling, being easily charged with static electricity, and having low hygroscopicity. In particular, it is difficult to dye in dark colors,
This disadvantage significantly narrows the range of applications of polyester fibers.

Generally, when dyeing polyester fibers, disperse dyes are used because they are affected by hydrophobic groups in the fiber structure. At this time, the polyester fiber has high crystallinity and the structure is dense, so it is dyed at a high temperature and high pressure of 120 to 130 ° C. or dyed at a temperature of about 110 ° C. or a normal boiling state using a carrier. Is used.

[0004] However, the method of dyeing under high temperature and high pressure has problems such as complicated operation of the machinery used for dyeing and high cost in terms of energy. In addition, when a fiber mixed with another kind of fiber is used, if the same bath dyeing is performed under high temperature and high pressure, another kind of fiber (especially wool, polyurethane fiber, etc.) has a problem that physical properties such as sagging are caused. .

In the dyeing method using a carrier,
Carriers as dyeing assistants generally have a large amount of harmful substances and are therefore difficult to handle, so that there is a problem that wastewater treatment and the like are costly. Furthermore, since the carrier deprives the dyeing seat of the dye in the fiber, it is difficult to dye it in a dark color, migration of the dye is liable to occur, and this causes defects such as spotting at the time of dyeing. is there.

Further, as a polyester fiber aimed at improving the dyeability with a disperse dye, there has been proposed a polyester fiber obtained by copolymerizing isophthalic acid, adipic acid, polyalkylene glycols and the like. For example, Japanese Patent Publication No. 57-25646 describes a fiber made of polyester obtained by copolymerizing polyethylene glycol having an average molecular weight of 300 to 4000.

However, since the polyalkylene glycols have an ether bond in the structure, the resulting fiber tends to have poor light resistance, change in color tone, and have a problem of coloration after dyeing. .

[0008]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems and provides a sufficiently dark color at normal pressure when dyeing with a disperse dye without using a carrier or the like. It is a technical object to provide an easily dyeable polyester fiber which can be dyed, maintains sufficient mechanical properties (strength, elongation, etc.) even after dyeing, and has excellent light resistance. .

[0009]

That is, the present invention provides a polyalkylene glycol having an average molecular weight of 400 to 2,000 by weight of 2 to 10% by weight and an average particle size of 3.0 μm.
The subject matter is an easily dyeable polyester fiber comprising polyalkylene terephthalate containing the following cerium oxide particles in an amount of 0.05 to 5% by weight.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The polyester used as a base in the present invention is polyalkylene terephthalate, specifically, PE
T, polybutylene terephthalate (PBT) is preferred. The polyalkylene terephthalate may contain a small amount of a copolymer component as long as the essential effect is not impaired, and these copolymer components include 5-sodium sulfoisophthalic acid, isophthalic acid, phthalic anhydride, and naphthalene. Aromatic dicarboxylic acid components such as dicarboxylic acid, aliphatic dicarboxylic acid components such as adipic acid and sebacic acid, diethylene glycol, propylene glycol, 1,4-cyclohexanedimethanol, and glycol components such as alkylene oxide adducts of bisphenol A and bisphenol S And hydroxycarboxylic acid components such as 4-hydroxybenzoic acid and ε-caprolactone.

In the present invention, the polyester contains a polyalkylene glycol in order to impart easy dyeability. In order to dye a sufficiently dark color under normal pressure, particularly at 100 ° C. or lower, a polyalkylene glycol having an average molecular weight of 400 to 2,000 is used, and the content in the polyester is 2 to 10% by weight, preferably 4 to 8% by weight. It is necessary to add so that In the present invention,
The polyalkylene glycols include those having etherified or esterified terminals.

If the average molecular weight of the polyalkylene glycol is less than 400, sufficient dyeing properties cannot be obtained, and if the average molecular weight exceeds 2,000, light fastness is reduced and discoloration by light after dyeing becomes remarkable. In addition, the compatibility with the polyester becomes poor, and the operability during spinning is remarkably reduced. On the other hand, if the content of the polyalkylene glycol in the polyester is less than 2% by weight, sufficient dyeability cannot be obtained, and
If the amount exceeds 0% by weight, the physical properties of the polyester are reduced, so that the operability during spinning is remarkably reduced, and the light resistance is lowered, and the discoloration due to light after dyeing becomes remarkable.

Examples of the polyalkylene glycol include polyethylene glycol and polypropylene glycol, copolymers thereof, and polytetramethylene ether glycol.

As a method for adding a polyalkylene glycol to the polyester, the polyalkylene glycol may be added during the production of the polyester (any stage from the beginning of the transesterification or esterification reaction to the beginning of the polycondensation reaction). Then, during spinning, polyester and polyalkylene glycol may be mixed and spun. In the latter case, the polyester and the polyalkylene glycol are melt-kneaded in advance using a single-screw or twin-screw kneader to produce a masterbatch, which may be added during spinning, or melt-blended during spinning. It may be spun while being spun.

In the present invention, the cerium oxide particles having an average particle diameter of 3.0 μm or less are added to the polyester containing the polyalkylene glycol as described above in an amount of 0.05 to 5 μm.
% By weight. Cerium oxide particles have an ultraviolet absorbing effect and function as a light-resistant agent, and by containing the same, enhance the light resistance of the polyester containing the polyalkylene glycol and prevent discoloration due to light after dyeing. Can be prevented.

Further, in the present invention, the cerium oxide particles as the light stabilizer are made of cerium oxide and talc or cerium oxide and silica, and the average particle diameter of which is 0.1 to 3.0 μm and coated with amorphous silica. It is preferable to use particles of

The ratio of cerium oxide and talc or cerium oxide and silica (excluding amorphous silica covering the surface) is preferably 15:85 to 50:50 by weight. If the proportion of cerium oxide is too small, the effect of absorbing ultraviolet rays to improve light resistance becomes insufficient, while if it is too large, the brightness of the polyester tends to decrease.

The amount of the amorphous silica coating the surface of the particles is preferably 15 to 25% by weight of the particles. If the amount of amorphous silica is too large, the ultraviolet absorbing effect of cerium oxide is likely to be impaired. May catalyze decomposition.

These light stabilizer particles have an average particle size of 3.
0 μm or less.
It is preferably 3.0 μm. If the average particle diameter exceeds 3.0 μm, the ultraviolet absorbing effect is reduced, light resistance is deteriorated, and the color tone of the polyester is deteriorated. 0.1 μm
If it is less, the production is difficult, the cost is increased, and agglomeration is likely to occur, and the dispersibility in the polyester tends to decrease.

The light stabilizer particles are contained in an amount of 0.05 to 5% by weight based on the polyester. Content 0.0
If the amount is less than 5% by weight, sufficient light fastness cannot be obtained, and if the amount exceeds 5% by weight, the particles tend to aggregate and not only deteriorate the spinning operability but also deteriorate the color tone of the polyester. Absent.

In order to incorporate such light-resistant agent particles into the polyester, the light-resistant agent particles must be mixed with ethylene glycol or 1,1.
Dispersed in glycol such as 4-butanediol and added at the time of polyester synthesis (any stage from the beginning of transesterification or esterification reaction to the beginning of polycondensation reaction). It is preferable to prepare a contained polyester (master batch) and add it at the time of spinning.

The polyester containing the polyalkylene glycol and the light stabilizer particles constituting the fiber of the present invention can be produced, for example, by the following method. A terephthalic acid and a diol are directly esterified to synthesize a polyester oligomer, to which an alkylene glycol and a diol dispersion of light stabilizer particles are added to carry out a polycondensation reaction.

The polycondensation reaction is usually carried out in the presence of a metal compound such as antimony, germanium, tin, titanium, zinc, aluminum, or cobalt under a reduced pressure of about 0.12 to 12 hPa at a temperature of 220 to 290 ° C. The intrinsic viscosity is 0.
It is preferable to perform the process until the value becomes 5 or more. Further, as long as the effect is not impaired, additives such as an antioxidant such as a hindered phenol compound, a cobalt compound, a fluorescent agent, a color tone improver such as a dye, and a pigment such as titanium dioxide are contained. You may.

Next, the obtained polyester is dried by a conventional method, fed to a usual melt spinning machine stand and melt-spun at a temperature higher than the melting point of the polyester by 20 ° C. or more. The fiber is obtained by winding it once as a semi-undrawn yarn, or by performing drawing, heat treatment and the like without winding it. In addition, as long as the effect of the present invention is not impaired, a composite fiber with another component may be used. Further, the form of the polyester fiber may be either a long fiber or a short fiber, and may be used after being subjected to post-processing such as crimping, false twisting, or treatment with a chemical solution, if necessary.

The polyester fiber of the present invention comprising the above-mentioned polyester preferably has a temperature (hereinafter, referred to as Tmax) at which the mechanical loss tangent tan δ at a measurement frequency of 10 Hz is maximum, of 60 to 90 ° C. In general, Tmax corresponds to the mobility of molecules in the amorphous portion of the fiber, and the higher the molecular weight of the polyalkylene glycol and the higher the content, the smaller the value. And the dyeability is improved.

When Tmax exceeds 90 ° C., the effect of improving the dyeability is reduced, and dyeing at a higher temperature is required. However, this value is not necessarily low, and if the molecular weight of the polyalkylene glycol is too large or the content is too large, 60 ° C.
, And problems such as a decrease in the mechanical properties and heat resistance of the fiber occur.

[0027] Further, the polyester fiber of the present invention comprises 8
Black lightness at the time of staining at 0 ° C. (hereinafter abbreviated as L80);
The difference in black lightness (hereinafter abbreviated as L130) at the time of dyeing at ° C. is preferably 5 or less. When the difference between L80 and L130 exceeds 5, the color development at 80 ° C. relative to the color development at 130 ° C. is insufficient, and the color is not dyed sufficiently dark at 100 ° C. or less at normal pressure. .

The values of L80 and L130 are values measured by the following method. After knitting the fiber and performing scouring at 60 ° C. for 20 minutes, the dyeing temperature was set to 80 ° C. and 1 under the following conditions.
After changing the temperature to 30 ° C. and staining for 60 minutes, a reduction treatment was performed at 80 ° C. for 20 minutes, and after air-drying, 15 minutes using a small pin tenter.
After heat setting at 0 ° C. for 1 minute, four sample pieces are prepared, and the L value is measured with a colorimeter (CR-100 manufactured by Minolta). <Dyeing conditions> Dye: Dianix Black BG-FS 3% owf Dispersant: Dispar TL 0.5 g / L pH adjuster: PH500 0.5 g / L Bath ratio 1:50

The polyester fiber of the present invention preferably has a black lightness retention of 85% or more after a light resistance test by irradiation with carbon fade for 20 hours. When the retention is less than 85%, the light resistance is not sufficient, and the discoloration after dyeing becomes remarkable.

The black lightness retention rate after the light resistance test is a value obtained by measurement according to the following method. A sample piece prepared under the above staining conditions (staining temperature of 80 ° C) was used as a sunshine weather meter (WEL-6XS-HC-B / EC type manufactured by Suga Test Instruments Co., Ltd.).
Is performed at 62 ° C. and 70% RH for 20 hours, and the L value before and after the irradiation is measured by a colorimeter (CR-100 manufactured by Minolta), and is calculated by the following equation. Lightness retention (%) = (L value before irradiation / L value after irradiation) ×
100

[0031]

The reason why the polyester fiber of the present invention has excellent dyeability and light resistance is not clear, but the inventors believe as follows. The polyester fiber of the present invention,
Since polyalkylene glycol having excellent compatibility with polyesters having an average molecular weight of 400 to 2,000 is used, hydrophilic soft segments are efficiently incorporated into the molecular chains of the polyester, and the hydrophobicity of the polyester is reduced. At the same time, the dense molecular structure is partially relaxed, so that the dye can easily enter the fiber, and it becomes possible to dye a deep color even at 100 ° C. or less under normal pressure. As a result, Tm
ax is an optimal value that balances dyeing properties and mechanical properties.
A fiber excellent in dyeability with a difference between 80 and L130 of 5 or less is obtained. In addition, by using cerium oxide and talc or silica as the light-resistant agent particles, the surface of which is coated with amorphous silica, the particles composed of cerium oxide and talc or cerium oxide and silica absorb ultraviolet energy. And, the radicals generated by absorption are blocked by the silica coating the particles,
Suppresses decomposition of polyester by radicals. Therefore, it is possible to increase the light resistance of the polyester containing the polyalkylene glycol and prevent fading after dyeing, and it is estimated that the retention of L80 after the light resistance test will be 85% or more.

[0032]

Next, the present invention will be described specifically with reference to examples. In addition, the measuring method and evaluation were performed as follows. (A) Intrinsic viscosity ([η]) Measured at a temperature of 20 ° C. using an equal weight mixture of phenol and tetrachloroethane as a solvent. (B) Strong elongation Using Orientic Tensilon RTC-1210, 50
cm sample was subjected to a tensile test at a speed of 50 cm / min, and was determined from its stress strain curve. (C) Measurement of Tmax Using a RSA-ii solid analyzer manufactured by Rheometric Scientific, a tan δ curve was measured at a heating rate of 5 ° C./min and a measurement frequency of 10 Hz in the range of 20 to 160 ° C. to determine Tmax. Was. (D) L80, L130 Measured by the method described above. The lower the L value of the dyed product, the deeper the color. In other words, the lower the L value, the better the dyeability, and the more dye is exhausted into the fiber. (E) Black lightness retention rate after light resistance test Measured and calculated by the above method.

The light-fastening agent particles used in Examples and Comparative Examples are the following five types. A: Particles composed of cerium oxide and talc whose surfaces are coated with amorphous silica, wherein the weight ratio of cerium oxide / talc / amorphous silica is 30/52/18 (Celigard T manufactured by Nippon Inorganic Chemical Industry Co., Ltd.) -3018) B: Particles composed of cerium oxide and silica whose surfaces are coated with amorphous silica and having a weight ratio of cerium oxide / silica / amorphous silica of 30/52/18 (Nippon Inorganic Chemical Industry Co., Ltd.) C: Cerigard S-3018) C: Particles composed of cerium oxide and talc whose surfaces are coated with amorphous silica and having a weight ratio of cerium oxide / talc / amorphous silica of 20/62/18 (Nihon Inorganic) D: Silica particles (Silicia 310, manufactured by Fuji Silysia) E: Talc particles (Microtalc CP10-40, manufactured by Pfizer MSP)

Example 1 A slurry of terephthalic acid and ethylene glycol having a molar ratio of 1 / 1.6 was continuously supplied to an esterification reactor in which a PET oligomer was present, and a temperature of 250 ° C., a pressure of 0.1 MPaG, and a residence time of 8 hours were used. The esterification reaction was carried out under the conditions
% Of PET oligomer was obtained continuously. 50.25 kg of this PET oligomer was transferred to a polycondensation reactor and the average molecular weight was
3.62 kg of 600 polyethylene glycol and 50 g of "Irganox 245" (manufactured by Ciba Geigy Japan, hindered phenolic antioxidant) as an antioxidant were added,
Stir and mix for 60 minutes. Thereafter, an ethylene glycol slurry having an amount of 0.25% by weight of the light-fast agent particles A (average particle diameter 2.0 μm), an ethylene glycol slurry having an amount of titanium dioxide of 0.4% by weight, and a total acid component 1
3 × 10 ⁻⁴ mol of antimony trioxide was added to each mol, and the temperature in the polycondensation reactor was raised to 275 ° C. in 30 minutes, and the pressure was gradually reduced to 1.2 hPa or less after 60 minutes. . Under these conditions, a polycondensation reaction was carried out for 4 hours while stirring, and the mixture was discharged and pelletized by a conventional method. Next, the pellets were dried by a conventional method, and then melt-spun at a spinning temperature of 290 ° C. using a usual melt spinning apparatus, and undrawn yarn was wound up at a speed of 1400 m / min. This undrawn yarn is supplied to a drawing machine, and 80
After preheating at ℃, it is stretched 3.5 times while being in contact with a heat plate at a temperature of 150 ℃, heat treated and wound up, and 75d / 36
f filament yarn was obtained.

Examples 2 to 5 and Comparative Examples 1 to 7 The same procedures as in Example 1 were carried out except that the molecular weight and content of polyethylene glycol and the type, particle size and content of the light-fastening agent particles were variously changed as shown in Table 1. Performed similarly.

Table 1 collectively shows [η] of the polyesters obtained in Examples and Comparative Examples, and physical properties and evaluations of the filament yarns.

[0037]

[Table 1]

As is clear from Table 1, in Examples 1 to 5, the yarn production and operability were good, and the obtained fiber was Tmax.
Is 60 to 90 ° C., the difference between L80 and L130 is 5 or less, which has excellent easy dyeability, and the retention of blackness after the light resistance test is 85% or more, and there is little fading due to light. Excellent light fastness. Also, it had excellent strength and elongation. on the other hand,
In Comparative Example 1, the molecular weight of polyethylene glycol was too small, and in Comparative Example 3, the content of polyethylene glycol was too small, so that the obtained fiber had too large Tmax, and the difference between L80 and L130 was large, which was sufficient. Dyeability was not obtained. In Comparative Example 2, since the molecular weight of polyethylene glycol was too large, and in Comparative Example 4, the content of polyethylene glycol was too large, the fibers obtained together were inferior in physical properties of high elongation. Was less than 85%, and the light resistance was poor. In Comparative Example 5, the rate of increase of the pack pressure during spinning was high because the content of the light-fast agent particles was too large,
Operability was extremely poor. Further, in Comparative Examples 6 and 7, since the light-fast agent particles were not suitable, the resulting fibers each had a black lightness retention of less than 85% after the light fastness test, and were inferior in light fastness.

[0039]

When the polyester fiber of the present invention is dyed with a disperse dye, it can be dyed in a sufficiently dark color under normal pressure, and has little fading due to light after dyeing and has excellent light resistance. Excellent mechanical properties such as strength and elongation.

Claims (3)

[Claims] 1. Cerium oxide particles containing 2 to 10% by weight of a polyalkylene glycol having an average molecular weight of 400 to 2,000 and having an average particle diameter of 3.0 μm or less are contained in an amount of 0.05 to 10%.
An easily dyeable polyester fiber comprising a polyalkylene terephthalate containing 5% by weight. 2. The cerium oxide particles comprising: cerium oxide;
2. The easily dyeable polyester fiber according to claim 1, wherein the fiber is made of talc or silica, and has a mean particle diameter of 0.1 to 3.0 [mu] m, the surface of which is coated with amorphous silica. 3. The temperature at which the mechanical loss tangent tan δ at the measurement frequency of 10 Hz is maximum is 60 to 90 ° C.,
The difference between black lightness at 80 ° C dyeing and black lightness at 130 ° C dyeing is 5 or less, and the retention of black lightness after a light resistance test by carbon fade irradiation for 20 hours is 85% or more. Easy-dyed polyester fiber.