JPS59100737A - Polyester composite crimped yarn and production thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyester composite crimped yarn and a method for producing the same. More specifically, the present invention relates to a polyester composite crimped yarn suitable for fabrics having the dual functions of water- and oil-repellency and elasticity with excellent durability such as wash resistance, and a method for producing the same.

In recent years, the requirements for the elastic properties of woven and knitted materials have become even stronger. This is because the elasticity of woven and knitted materials is closely related to the comfort of wearing clothes, and those with good elasticity can easily follow the movements of various parts of the body, so there is no feeling of pressure. This is because it has the advantage of allowing activities to be carried out smoothly, and it also has the advantage of not easily forming wrinkles.

Generally, when imparting stretchability to a woven or knitted fabric, since the constituent structure of the knitted fabric is loose, stretchability can be imparted relatively easily using ordinary false-twisted yarn, etc.; Since the constituent structure is denser than that of , it is not possible to obtain a fully satisfactory stretch fabric even if ordinary false twisted yarn is used. However, woven fabrics have other characteristics that knitted fabrics do not have, such as texture and luster, so it is important to take advantage of these characteristics and add stretch performance. has been desperately requested.

The present inventor previously reported in the specification of % Application No. 56-141630 that there are few fabrics having such stretchability (total 15
% elongation and long straw, and this fabric is a polyester composite fiber consisting of polybutylene terephthalate (hereinafter abbreviated as PBT) and polyethylene terephthalate (hereinafter abbreviated as PET), and is also false-twisted and crimped. 9. Obtained by using a crimped elastic yarn which is a composite crimped yarn and has a crimp ratio ('rc+o) of 8% or more when subjected to water production treatment under a load of 10 Da/a. I suggested that.

Fabrics using such crimped elastic yarns have powerful stretchability and are therefore suitable for fields that require stretchability, such as working clothing and sports clothing. However, in order to expand into the field of clothing for all kinds of outdoor sports, such as mountaineering clothing or skiing clothing,
This was difficult because the woven fabric using the crimped elastic yarn lacks water and oil repellency.

Therefore, the present inventor attempted to make a moisture-permeable waterproof fabric by laminating a porous film of polytetrafluoroethylene on this stretchable fabric, but the porous film of such a laminated +-fA product lacks stretchability. Therefore, the elasticity of the fabric is greatly reduced, and because of the added stress of film button expansion and contraction, peeling occurs between the film and the fabric, resulting in a product that cannot be used for practical purposes. It has not been possible to create a product that has both oiliness and elasticity at the same time.

From the above formula, the present inventor believes that if water and oil repellency can be imparted to the threads constituting the stretchable fabric during the spinning process, a crimped elastic yarn with water and oil repellency can reasonably be obtained. Moreover, we thought that we could obtain a fabric with the functions of water and oil repellency and elasticity without the drawbacks such as peeling of the film due to expansion and contraction.As a result, we conducted further inspections. Bed compound (JP-A-55-90677 1% JP-A-52-5400
No., JP-A No. 57-171760.

JP-A-57-171761, JP-A-57=17176
It has been discovered that the above object can be achieved by a composite crimped elastic yarn made of PBT and PET to which PBT and PET (see Publication No. 2) are fixed, and the present invention has been achieved.

That is, in the present invention, a PBT component whose main constituent is polybutylene terephthalate and a PET component whose main constituent is polyethylene terephthalate are combined in a side-by-side type or an eccentric sheath core, and are false-twisted. A polyester composite crimped yarn which is a crimped polyester composite yarn and is characterized by simultaneously satisfying the following (a) to (b) and exhibiting water and oil repellency with excellent washing resistance. It's a thread.

(a) The crimp rate (TC,.) is 8% or more when the yarn is treated with water under a load of 101 $/d.

(b) A sea bed compound exhibiting water and oil repellency is fixed to the thread.

Enshou se ↓ Denshu' Makae-Y to VEi- A PBT component whose constituent component is polybutylene terephthalate, and a PBT component whose main constituent component is polyethylene terephthalate, and whose intrinsic viscosity [η)PE
0.05 wt% of a sea bed compound exhibiting water and oil repellency is added to a yarn obtained by composite spinning a PET component with a T of 0.55 or less in a side-by-φ side type or an eccentric sheath core type.
After the above-mentioned application, a single heater false twisting process is carried out at a false twisting heater temperature of 150'C or higher.A method for manufacturing a polyester composite crimped yarn, and commercially available λ+, b.

The present invention will be further explained.

The composite crimped elastic yarn made of PBT and PET, which has durable water and oil repellency, not only has the water and oil repellent to which it is fixed, but also has sufficient water and oil repellency. It is important that the fibers are uniformly distributed in the yarn and that they are layered on the surface of the single fibers constituting the yarn to form a tough coating.

From this point of view, the water and oil repellent agent fixed to the crimped elastic yarn has a group in each molecule that exhibits water and oil repellency and a group that provides intermolecular cohesive force and adsorption force bonded to the mother nucleus. It is preferable to be there. This point will be explained by citing a fluorine compound represented by the following general formula [E] as a water and oil repellent used in the present invention, but the present invention is not limited thereto.

......CI) (However, X is fluorine or a perfluoroalkoxy group containing 1 to 6 carbon atoms, m is an integer of 2 to 20 as an arithmetic average, and Y is alkylene, dichloroflukylene, or alkyleneoxy a group consisting of 2 to 20 carbon atoms, containing at least 2 carbon atoms in the main chain; 2 is oxygen or nitrogen; if 2 is oxygen, p is 11; if z is nitrogen, p is 2; .R and R' are H or a C1 to CI4 hydrocarbon group, aryl group, or aralkyl group-hydroxyalkyl group.B is -CH, R'CHOH or -CH, R'CHO
CH, R'CHOH, in which R' is hydrogen or a methyl group, or B is -CHICH(OH)CHIQ, in which case Q is...a rogen atom, a hydroxyl group, or a -tolyl group, and B is -CHtCH (OEl)CHtOCHtCH(
OH) CHaQ (Q is the same as above). t is 0.1 or 2, r and q are integers of at least 1, and the sum of r 1 q + t is 4.

X (CR)rn and Y are linear bibranched or cyclic.

In addition, the substituents in the above general formula are the same or different)l) Due to the presence of the B group of 1000B in the fluorine compound, a strong repellent is formed on the single fiber surface Kg & at the position closest to the synthetic fiber polymer. Forms a water and oil repellent film. Moreover, even if such an agent is mixed into an oil agent and applied, the agent is distributed on the uppermost part of the fiber surface, so the oil agent has the advantage that it can perform the same function as a conventional oil agent. The preferred structure of group B is -cut OH(O
H) C1 to CI4 or 10H*CH(OH)CHtO
CHtCH(0)t)CH, (J.

2) Furthermore, the perfluoroalkyl group in the molecule that minimizes surface free energy exhibits excellent water and oil repellency.

3) In addition, the emulsion dispersibility is significantly improved by introducing a sulfonamide structure into the fluorine compound molecule, making it possible to create a stable emulsion treatment liquid with almost no precipitation in the emulsion circulation pipe and emulsion tank. This makes it easier to form a uniform, durable water- and oil-repellent coating.

In addition, 2 in the above general formula CI) is particularly preferably oxygen from the viewpoint of ease of synthesis, and also has a well-balanced effect of adsorption to fibers, water repellency, oil repellency, and improvement of emulsification and dispersibility.
In order to maximize the performance, q r r is q = r =
2 is particularly preferable. Incidentally, a large number of formula primes disturbs the arrangement of the fluorine compound groups and adversely affects water and oil repellency, so it is better to have a smaller number of constituent carbon atoms, and a propyl group is particularly preferred from the viewpoint of ease of synthesis.

4) Also, the hydrocarbon group in the form of -(CO2R')t is
Although its function is lower than the above-mentioned groups containing -COOB or So, N, -(CO,R') itself may lower the molecular specific gravity of the agent and facilitate emulsification and dispersibility.

Furthermore, the composite crimped yarn made of PBT and PET to which such an agent is fixed has a crimp rate ('rc+o) of 8% or more, preferably 10% or more when treated with seawater under a load of 10 to 100 d/d. There needs to be. Here, if TC+o is less than 8%, the fabric using the crimped yarn will exhibit water-rupture and oil repellency as described above, but its elongation rate will be less than 15% and it cannot be called a stretch fabric. Become.

Furthermore, even stretch fabrics made of crimped yarns to which the above agent has been applied and have a TC of 8% or more are required to exhibit water and oil repellency with excellent washing resistance. That is, the water repellency of the fabric after washing five times is 300 seconds or more, and the oil repellency is also grade 5 or higher.

Here, if the water repellency of the fabric after 5 washes is less than 300 seconds or the oil repellency is less than 5R, it cannot be put to practical use as outdoor sports clothing, which is the main use of such fabrics.

The water repellency and oil repellency referred to herein are measured by the following method.

b) Use a 20% by volume aqueous solution of water-repellent inpropyl alcohol. The time (seconds) it takes for the water droplet to disappear after a drop is placed on the sample.
Measure.

(b) 41 Oil Based on AATCo 118-1972. One drop of the reagent indicated by Kfe-1 is gently dropped onto the surface of the horizontally spread sample, and the state of penetration is judged after 3 seconds.

Table 1 In order to obtain the crimped yarn described above, a specific amount of a water-refining compound exhibiting water and oil repellency is added to a yarn obtained by composite spinning of PUT and PET with a specific intrinsic viscosity. It is important to perform the false twisting process under specific conditions.

In the present invention, the intrinsic viscosity (η) Ph:T of the PET component, which is one of the components to be composite-spun with PBT, is 0.55.
It is necessary that the following is true. here.

If [η] exceeds 0.55, the PB of the PET component
T The tension heat setting performed to sufficiently reduce the heat shrinkage stress compared to the pressure of the PBT component is insufficient, and the PET component remains with a large heat shrinkage stress. Therefore, the TC of the obtained crimped yarn. is less than 8%. On the other hand, the intrinsic viscosity [η]PBT of the PBT component is 0.7 or more, preferably 0.
．． It is preferable to set it to 8 or more. This is because with such a high viscosity PBT component, the degree of orientation during spinning is PIIET.
Mechanics of crimp, expansion and contraction after subsequent stretching or false twisting 4? This is because it allows you to fully demonstrate your sexuality.

Considering the spinning stability, the composite ratio of such composite fiber is such that the ratio of PBT component is 30 to 70%, preferably 35 to 6.
5%, the proportion of PET component is 70-30%, preferably 6
A proportion of 5 to 35% is preferred.

The composite spun yarn is wound at a constant speed via a roller. Next, it is stretched at a predetermined magnification and then subjected to false twisting. At this time, the spinning take-off speed is set to a relatively high speed, for example, z0
The undrawn yarn wound at a speed of 00 m/Jli1 or more can also be subjected to drawing and false twisting.

In addition, the amount of water-making compound is 0.05wt5 based on the yarn @ amount.
As mentioned above, it is necessary to apply preferably 0.twt% or more before false twisting. The imparted view of this water-making compound is 0,
If it is less than 0.05 yt%, sufficient water and oil repellency cannot be exhibited.

It is preferable to apply such a water-refining compound by mixing it into an oil, particularly a spinning oil, together with the spinning oil. This is because the water-forming compound is sufficiently adsorbed onto the fiber surface by being heated to a high temperature in the subsequent process, thereby improving the durability of water and oil repellency.

Examples of the oil at this time include spinning and drawing.

In order to maintain the productivity of various processes such as crimping and weaving, it satisfies the required characteristics in each process such as lubricity, antistatic property, focusing ability, and heat resistance that can withstand the thermal separation of oil on the heater. It is fine as long as it is done.

As the optimum oil agent, a heat-resistant ester smoothing agent is preferably used as the smoothing agent component. For example, - basic acid esters can be used as a single component of an ester smoothing agent such as dibasic acid esters, polybasic acid esters, thalaichol esters, polyhydric alcohol esters, and aromatic carboxylic acid esters, or as a composite component thereof. The main component is mineral oil, polypropylene glycol, polyisobutylene, polypuran, or polyether. Such smoothing agents include alkyl phosphates, alkyl sulfonates, alkyl sulfosuccinates, alkyl sulfates and/or their fullylene oxide adducts, which also serve as nonionic emulsifiers and antistatic properties, or alkali metal salts and ammonium salts of higher fatty acids. There are no particular restrictions on the oil agent, as long as it is used in combination with a cationic activator, an amphoteric surfactant, etc., and satisfies the emulsion stability of the finishing agent containing the deep purple compound, as well as the silk-forming process and post-processing process.

Furthermore, the yarn to which the dark purple compound has been added in this way has a false twisting heater temperature of 150°C or higher, preferably 150 to 210°C.
It is necessary to perform a single heater false twisting process at ℃. Here, when the temperature of the false twist heater is less than 150° C., the TC of the obtained crimped yarn is less than 8%. Moreover, after the dark purple compound is applied, the false twisting process is applied and there are 15 threads in between.
If it is not heated to 0° C. or higher, the durability of water and oil repellency will also be poor.

In addition, in the heater false twisting process in which a relaxation heat treatment is performed after false twisting, TC,o becomes less than 8%.

In addition, the PBT component referred to in the present invention is a repeating unit of 8
It is preferable that it is composed of butylene terephthalate in an amount of 0 mol % or more, particularly preferably 90 mol % or more. When the content of butylene terephthalate is less than 80 mol%, there is a tendency for the dyeing properties such as washing resistance and weather resistance to deteriorate.

On the other hand, the PET component is preferably composed of ethylene terephthalate in an amount of 80 mol% or more, preferably 90 mol% or more of repeating units. When the ethylene terephthalate content is less than 80 mol%, the crimp ratio TC,0 of the resulting crimped yarn tends to be less than 8%.

The above-mentioned polybutylene terephthalate contains a third component, for example isophthalic acid, phthalic acid, in a proportion of up to 20 mol%, preferably up to 10 mol%.

Dicarboxylic acids such as methyl terephthalic acid and adipic acid, and diglycols such as ethylene glycol, trimethylene glycol and neopentyl glycol may be copolymerized, or a small amount of other polymers, titanium oxide, calcium carbonate, etc. may be copolymerized. It may contain a matting agent and other known additives.

Further, polyethylene terephthalate contains a third component such as the aforementioned dicarboxylic acids, trimethylene glycol, and tetramethylene glycol in a proportion of 20 mol % or less, preferably 10 mol % or less.

Diglycols such as neopentyl glycol may be copolymerized (or may contain small amounts of other polymers, matting agents such as titanium oxide, calcium carbonate, and other known additives).

The fabric obtained using the crimped yarn of the present invention described above is a stretch fabric that has both an elasticity of 15% or more and durable water and oil repellency.

The present invention will be explained below with reference to Examples, but first, toq/
The methods for measuring the crimp rate TC1°, [η], [η]PoT and hiBT fabric elongation of the spun yarn when subjected to water production under a load of d will be explained.

(a) Crimp ratio TC when water production treatment is performed under a load of 10 Pn9/de.

A skein of about 3000 de is made by applying a tension of 50 m9/de to the sample and winding it up into a skein. After making the skein, a load of 21v/do +20019/de is applied to one end of the skein, and the length A'o (e) is measured after 1 minute has elapsed. Then remove the load of 200 m9/de and
The sample is treated in 100° C. fluorinated water for 20 minutes with a load of e (that is, a load of lO da/de is applied to the sample). Immediately after seawater treatment, the entire load is removed and air-dried freely for 24 hours. A load of 2 Da/de+zoo to/de is applied again to the air-dried sample, and the length 21 (α) is measured after 1 minute has elapsed.

Then, the load of 200 t/de is removed, the length i is measured after 1 minute has elapsed, and the crimp ratio TC is calculated using the following formula.

-”　’xio.

TCl. c%) 7 The above measurement must be carried out after three days or more have elapsed after the production of the crimped yarn.

(b) Intrinsic viscosity of the PBT component and PET component of the spun thread [η] PBT・(η) PET For a sample in which each component was separately discharged under the same spinning conditions as the composite spinning condition, the concentration of orthochlorophenol was 3.
Measured in 5°C solution.

C9 fabric elongation rate A sample of length 30 boxes and width 5 clL was prepared in the weft direction of the fabric, and each i
o Add a mark at position 01+1 (length between marks is 200.
). One end of this sample was clamped and fixed with a chuck with a width of SOW, and a load of 1.5 kg was attached to the other end. After leaving it for 5 seconds, the length L (dragon) was measured using the following formula. calculate.

Example Using a commercially available composite spinning machine, polybutylene terephthalate having an intrinsic viscosity of 0.86 and polyethylene terephthalate containing 0+3% by weight of titanium oxide and having an intrinsic viscosity of 0.47 were respectively melted. 19108
PBT from the nozzle described in the publication having 48 & 11 discharge ports.

The PET component was discharged at a discharge ratio of so:so and wound at a spinning speed of 25,007 FL/min.

The sea bed compound used in this example is a mixture of pyromellitic acid esters having the following structure.

C3H.

凰(b) However, B = -CH2CH((M)C1Iβ1n=8
(Average value) For convenience, this pyromellitic acid ester mixture is hereinafter referred to as fluorine compound composition (F). A mixture of seabed compound composition CF') with an emulsifier and an anion (undiluted solution mixture-1) and a mixture of coconut oil as a smoothing agent component with an emulsifier (undiluted solution mixture-2) were each heated to 80°C, and first the undiluted solution was mixture-
2 was stirred and added to water at 80°C, followed by stock solution mixture 1, emulsified and dispersed, and after uniform stirring, the mixture was cooled to 35°C.

The spinning finishing oil obtained in this way is shown in Table 2.
- Prepared to the composition of V, with an additional oil hardness of 20% by weight.
The emulsion was adjusted to a stable translucent emulsion.

About 1.0% by weight of the spinning finishers IV shown in Table 2 were applied to the undrawn polyester composite yarn after spinning and solidification to give the fibers a preconcentration effect on the yarn.

Table 2. Using a commercially available one-stage drawing machine, approximately 12
The film was heated to 0° C. and stretched so that the elongation at break was 30%.

Next, the obtained composite yarn was false-twisted using a commercially available single-heater spindle false-twisting machine with a twist number of 2650 T/M and the heater temperature varied as shown in Table 3, thereby forming a polyester composite yarn. I got a curly thread. The false twisting speed was 120 m/min, and the ratio of yarn supply speed to take-off speed was adjusted so that the yarn cutting elongation after false twisting was y25%.

Furthermore, using a suitable commercially available loom with the obtained crimped yarn, warp yarn density 26.5/cri r weft density 25.9 yarn/α toshi warp was commercially available polyester single heater false twisted yarn 15
A plain woven fabric was created using 0 denier 48 filament yarn and the crimped yarn created above.

1 each of score roll and soda ash
9711 was added, followed by relaxing treatment for 20 minutes in 70°C warm water adjusted to pH = 6.7 by adding acetic acid, and further 1
It was preset for 45 seconds in hot air at 80°C. Sara 1c1
A fabric was obtained by soaking and setting for 45 minutes in a dye bath at 30°C and adjusted to pH = 6.4 by adding acetic acid.

The table below shows the results of measuring the elongation rate, water repellency, and oil repellency of this fabric.
It is also shown in 3.

Table 3 Here, Lo indicates the performance after washing Wjlo times, and L indicates the performance after washing 5 times. Blue Comparative Example/16 In summer, the temperature of the false twisting heater is as low as 140'C, so
The crimp rate is as low as 7.0%, and therefore it is not possible to obtain an elongation rate of 15%, which is preferable for a stretch fabric. In addition, although water and oil repellency initially show good values, as the number of washings increases, durability deteriorates and the water and oil repellency decreases significantly. On the other hand, TC at /%7,8. Although it has a high elasticity and is desirable as a stretch fabric, its water and oil repellency is at a low level. (For /i67, the amount of adhesion of sea bed compound composition CF) is small, and its durability is also low. ) Examples with /%2 to 6 have a crimp rate TC,o of 8% or more, which maintains a stretchability of 15% or more, which is preferable for a stretch fabric, and also has high levels of water repellency, oil repellency, and durability. be.

Comparative Example Spinning, stretching, and false twisting were carried out in the same manner as in Example /I64, except that the [η)PET of the PgT component was changed to 0.61. The TC of the obtained processed yarn was 6.6%. When we measured the elongation rate and water and oil repellency of a plain woven fabric using such processed yarn, the water repellency was 300 seconds or more in both LOIL, and the oil repellency was also grade 6 in LO.

L, was grade 5. However, the elongation rate is 12.4
%, and the fabric was not stretchable.

Patent applicant Teijin Ltd.

Claims (1)

[Claims] fi+ A PBT component whose main component is polybutylene terephthalate and a PET component whose main component is polyethylene terephthalate are combined in a side-by-side type or an eccentric sheath core type, and A polyester composite crimped yarn to which false twist crimp is applied, which satisfies the following (a) to (b) at the same time and exhibits water and oil repellency with excellent washing resistance. Composite crimped yarn. (a) The crimp rate (TC, 0) when the yarn is treated with seawater under a load of 10 rng/d is 8% or more. (b) A sea bed compound exhibiting water and oil repellency is fixed to the thread. (21) The polyester composite crimped yarn according to claim il+, wherein the sea bed compound is a sea bed compound represented by the following general formula CI. (However, X is a sea bed or a perfluoroalkoxy group containing 1 to 6 carbon atoms, m is an integer of 2 to 20 as an arithmetic average, and Y is alkylene. Cycloalkylene or alkyleneoxy group with 2 to 20
carbon atoms and contains at least 2 carbon atoms in the main chain. 2 is oxygen or nitrogen, and when 2 is oxygen, p is 1. When 2 is nitrogen, p is 2. R and R' are H or a CI to C84 hydrocarbon group, an aryl group, an aralkyl group, or a hydroxyalkyl group. B is 10Ha R'CHOH or -CH2R'CHO
CH, R'CHOH, where R' is hydrogen or a methyl group, or B is -cutCH(OH)CH,Q, where Q is a halogen atom. hydroxyl group or nitrile group, and B is -CHICH(OH
)OH, OCH, OH(OH)CH,Q. (Q is the same as above). t is 0.1 or 2, r and q are integers of at least 1, and the sum of r + q + t is 4
It is. X (Cp,')m and Y are linear bibranched or cyclic. In addition, the substituents in the above general formula may be the same or different. ) (3) Claim No. 2 in which 2 in the general formula CD is oxygen and the substituent R on the nitrogen atom is a propyl group
The polyester composite crimped yarn described in section 2). (4) qlr and t of general formula CI) are q = r =
2. The polyester composite crimped yarn according to claim (3), wherein 1=0. (5) A PBT component whose main component is polybutylene terephthalate, and a PET component whose main component is polyethylene terephthalate and has an intrinsic viscosity [η]
is 0.55 or less, by side-by-
A seabed compound that exhibits water and oil repellency on yarns spun in a side type or eccentric sheath core type.
1. A method for producing a polyester composite crimped yarn, which is characterized in that after imparting t% or more, false twisting is performed with a single heater at a temperature of 150° C. or higher using a false twisting heater. (6) The method for producing a polyester composite crimped yarn according to claim (5), wherein the sea bed compound is a sea bed compound represented by the following general formula CI). ......CI) (However, X is a sea bed or a perfluoroalkoxy group containing 1 to 6 carbon atoms, m is an integer of 2 to 20 as an arithmetic average, and Y is alkylene. Cycloalkylene or 2 to 20 alkyleneoxy groups
carbon atoms and contains at least 2 carbon atoms in the main chain. 2 is oxygen or nitrogen; when 2 is oxygen, p is 1; when Z is nitrogen, p is 2. R and R' are H or a CI to CI4 hydrocarbon group, an aryl group, an aralkyl group, or a hydroxyalkyl group. B is -CH, R'CHOH or -Cf(, R'CHOC
H, R'CHOH, where R" is hydrogen or a methyl group,
Or B is -CH,CH(0H)CHtQ, in which case Q
Is it a halogen atom? Hydroxyl group or nitrile group, further B is -
C'I(,CH(OH)CHt ocii,CH(OH
)CHtQ. (Q is the same as above). t is 0
．． 1 or 2, r and q are integers of at least 1, and r
The sum of +q+t is 4. X(CF,)m and Y are straight chains. Branched or cyclic. In addition, the substituents in the above general formula may be the same or different. (7) A method for producing a polyester composite crimped yarn according to claim (5), wherein the sea bed compound is applied together with a spinning oil. (8) In the general formula CI), 2 is oxygen, and the substituent R on the violet atom is a propyl group.
) A method for producing a polyester composite crimped yarn as described in item 2. (9) The method for producing a polyester composite crimped yarn according to claim (8), wherein q r r and t in general formula CI) are q=r=2°j=o.