DE2140553C3 - Process for the production of clothing materials from knitted or knitted goods containing polyester - Google Patents

Description

The invention relates to a method according to the preamble of claim 1.

A method for hot pressing knitwear is from the German utility model specification 18 45 077 known in the known method is a knitted or knitted fabric from a yarn, which by Twisting two single threads is made, one of which is made from fully synthetic fibers such as Example consists of polyester fibers and the other has a high proportion of cellulose fibers among such Conditions hot-pressed that the touching thread sections in the mesh are made of fully synthetic Fibers are welded together at the joints. The knitted fabric or knitted fabric at the same time with the application of the required temperature in one of the training on the finished Garment corresponding predetermined shape are pressed. For welding synthetic Fibers must at least have their softening temperature, for polyester fibers about 230 to 240 ° C, be heated.

The hot pressing of woven goods is a well-known measure for textile finishing. According to the German Offenlegungsschrift 19 64 172 is for finishing textile fabrics, such as worsted or woolen fabrics, certain composite fabrics made from worsted or woolen yarn or from mixed yarns made from synthetic fibers It is necessary to press the fabric in order to make the fabric dimensionally stable and give it a grip and improve shine.

A chip press suitable for this is described in "Melliand Textile Reports", 5, pp. 520, 521 (1965). It This is a fully automatic, electro-hydraulic chip press, which is used to achieve high quality Gloss and smoothness effects are used on worsted and strejehgam goods. The press can press pressure generate up to 12 MN, which results in a maximum surface pressure of 35 bar,

Working conditions with a chip press can also be found in Bernhard's book "Appretur der Textilien". See pp. 142-144 (1960). Then the woven goods are each with a pressboard between each Fabric layer laid in folds - chipped in - and with

ίο a certain height of the stack of goods in the chip press. Although a pressing in cold condition already results in an effect, better effects are achieved by heating the stack of goods Pressing required pressure is provided by a pump generates an operating pressure of up to 400 bar. Di «: Goods have to be pressed for several hours, about 8 to 12 hours, with the cut goods being ^{heated to 40 to 80 °} C. in most cases. Then it is re-machined and the pressing process is abbreviated and repeated again This gives the goods a wall, noble sheen produced The chip press can also be used to press knitted woolen jersey, but leave it alone similar effects can be achieved through a decatur on the finishing decating machine or on the special tricot calender and the production is greater here than on the chip press.

The object of the present invention is to provide a method to produce knitted or warp knitted goods Clothing fabrics with a fabric-like surface to generate surface structure. A fabric-like upper According to the invention, a surface structure is present when the treated goods have a porosity of at most 80%, in particular from 75 to 40%, and a surface contour value of at most 6, in particular below 4,

J5 has.

The porosity of the substance is defined as follows:

Porosity (%) = -

100

where S stands for the density of the fabric and s for the density of the fiber of which the fabric is made. For the Knitted or knitted goods suitable for the process according to the invention have, for example, a density of 0.35 to 0.45 g / cm ³ ; the density of polyethylene terephthalate fibers is 1.38 g / cm ³ and that of wool fibers about 1.32 g / cm ³ . As is known, wise knitted or

Fabrics knitted in this way have a low density, so that such fabrics have a higher porosity for the same weight have as woven goods made from the same fibers. For example, has a patterned double jersey pure polyester yarn with a weight per unit area of 230 g / m ^J and a thickness of 1.03 mm a porosity of 84% and a surface contour value of 9.

The surface contour value is a measure of the Smoothness of the surface and becomes from the difference

between the uppermost fiber tips or loops those in adjacent, each 0.05 mm wide sections ten determined. A detailed procedure for determining the Surface Contour value is given later specified. The inventive solution to the set task

hi be is a method with those specified in claim 1 Features. Advantageous developments of the method according to the invention emerge from the Claims 2 to 4.

10

15th

By means of the method according to the invention, knitted fabric is turned into a fabric with a woven fabric Appearance and a fabric-like feel, an even and smooth surface, a low one Coefficients of friction, a high apparent density and a relatively low air permeability, which is suitable for the production of women’s and men’s clothing Operating speed of the modern knitting and knitting machines produced knitted goods according to the invention can be further processed into fabric-like substances. As a result, the invention extends The application possibilities for polyester fibers and for knitted and knitted goods containing polyester fibers are tempting.

The method according to the invention is described below with reference to FIGS. 1 to 5 in detail explained; it shows

F i g. 1 shows a graph of the relationship between compression pressure and degree of deformation of polyester knitted fabric and the consequences of heat setting,

2 shows the relationship between air permeability and deformation in a graphical representation Polyester fabric,

Fig. 3 and 4 details for determining the surface contour of the substance and

F i g. 5 a device for measuring the coefficient of friction of the fabric surface.

The knitted or knitted goods provided for the method according to the invention can be made from jersey fabrics, Tricot fabrics and the like that contain at least 50% by weight polyester fibers. Preferably be the fabrics are selected from knitted fabrics that have a relatively high basis weight, such as double jersey, double tricot or the like. The knitted or knitted fabric can be made of multi-thread yarns, in particular textured or spun yarn. Suitable polyester fibers consist of polyester, such as

Polyethylene terephthalate,
Polymethylene terephthalate,
Polytetramethylene terephthalate,
Polycyclohexyldimethylene terephthalate,

as well as copolymers and mixtures of these polyesters.

The permanent deformation of the thread layer of a thread when pressed together mainly depends on the pressing pressure, the pressing time and the pressing temperature. In particular, the pressing temperature is essential Influence on the degree of deformation of the fabric in the direction of the thickness. The degree of deformation becomes as follows Are defined:

30th

35

40

Degree of deformation (%) =

D ₀

100

55

where Do stands for the thickness of the original knitted or knitted fabric and D \ for the thickness of the pressed fabric. The thickness of the fabric can be measured according to ASTM D 1777-64, for example.

In the method according to the invention, the degree of deformation lies, that is, the reduction in thickness in the range between 5 and 45%, preferably in the range between 15 and 35%. This guarantees that the thickness of the knitted or knitted fabric after compression is only 95 to 55% of the original Thickness matters.

In the case of the method according to the invention, the at least Knitted or knitted fabric containing 50% by weight of polyester fibers at right angles to the fabric surface pressed together at a temperature between 90 and 130 ° C. The pressure is 5 to 35, preferably 10 to 25 bar. When the temperature and the pressure lie below the specified lower limit, the degree of permanent deformation is insufficiently low and the treated fabric may not have the desired fabric-like appearance and fabric-like appearance Gaining a grip. If the pressure is higher than 35 bar, the compressed material is too low Thickness unsuitable for use as a clothing fabric The length of time to press the knitted fabric is between 5 and 40 s.If the time is less than 5 s, there is a risk that the pressed fabric is insufficiently or unevenly pressed.

In Fig. 1, curve A shows the relationship between compression pressure and degree of deformation in a polyester knitted fabric which was obtained from a multi-filament textured polyethylene terephthalate, a thickness of 1.03 mm and a basis weight of 230 g / m ² , and which lasts for 20 seconds has been compressed under a pressure in the range from 0 to 35 bar at a temperature of 130 ° C. Curve A clearly shows that the degree of deformation increases with an increase in pressure

If the polyester knitted fabric pressed under the conditions mentioned is kept in boiling water for 30 minutes, then the degree of deformation corresponds to curve B. If the knitted fabric is aftertreated after completion of the pressing process, namely under a pressure of 200 to 300 mbar and with steam for 3 minutes at a temperature of 130 ° C., the aftertreated goods show a degree of deformation corresponding to curve C following the 30-minute treatment in boiling water. Since curve C lies above curve B , the aftertreatment is advantageous in order to maintain the new properties of the pressed knitwear

According to an advantageous development of the invention This process provides for the post-treatment of the pressed knitted or knitted fabric. For post-treatment, fixation with the ingress of moisture or a titanium fixation can be provided will.

The moisture setting is carried out at 110 to 130 ° C. under a pressure of 300 to 1000 mbar within 2 to 10 minutes, the moisture expediently being supplied by means of steam. The dry fixation is carried out as dry heating; this is to the temperature in the range between 150 and 200 ⁰ C, preferably in the range 170 190 ° C, to lie, and the treatment time is to at least 5 s, and preferably not more than 30 s.

The pressing device used is a device with which the knitted or knitted fabric for the intended Period of time can be pressed at right angles to the fabric surface and heated evenly. These are continuously operating flat presses and other presses provided with heating plates are suitable

The inventive method can be carried out simultaneously before or after the conventional treatment, such as. B. with a plasticizer, antistatic agents, light-resistant agents, fluorescent brightening agents, agents to increase the pill resistance, dirt-repellent and fire-resistant agents as well as with a Finishing resin.

The knitted or knitted fabric treated according to the invention has a much lower porosity than normal knitted fabrics and is therefore very warm and hardly permeable to air. In Fig. 2 is the relationship between the degree of deformation and the air-permeable wedge of the knitted or knitted fabric, which with Has been described with reference to FIG. From Fig. 2 it can be clearly seen that the air permeability decreased with an increase in the degree of deformation. It follows that an increasing degree of deformation to an increased filling of the free spaces in the material by the thermoplastic Fibers leads.

With reference to FIGS. 3 and 4, the "surface contour" parameter is explained.

According to a method for determining the surface contour, the knitted or knitted fabric is converted into a Melt of ethylene-maleic acid copolymer with a molecular weight of 2000, a melt

W ^ 9 t P ^ »P wtr ^^^ · ■■■■■ Pl P ^ r% ^ \ ■ ^^^% T» ^ »** ■ ■ Ρ" ^ νη t ^ * · ■ »» P ^^ »^ t ^ F ^ n ■ rm mr * r * p"

Temperature of 120 ⁰ C embedded, and the melt then solidified. The embedded knitted or knitted fabric is removed using a microtome at right angles to the fabric surface at intervals of 0.05 mm.

3 shows a corresponding thin section of the knitted or knitted fabric, the * axis running essentially parallel to the fabric surface and the / axis running at right angles to the fabric surface; accordingly, the length of the fabric is plotted along the x-axis and the thickness of the fabric along the y-axis. Each thin section is divided into 0.05 mm wide sections parallel to the / axis, which are referred to as small sections. The coordinates (x ", y") of the uppermost fiber or mesh end (S _n ) are determined in each small section (cf. FIG. 3). The determined coordinate values are entered in a diagram according to FIG. 4 and line 5 of the surface contour is thereby obtained. 1 mm long sections of the material are combined into a so-called large section and the difference between the maximum and minimum value of the v-coordinate is formed in each such large section (see FIG. 4 with the surface contour line 5 approximately 2.5 mm in size Sections The surface contour value corresponds to the number of large sections in which this difference value is 0.15 or more, per ten consecutive large sections.

The knitted or knitted fabric treated according to the invention has a surface contour value after the press treatment of at most 6, preferably 4 or less, or better 2 or less to at least? a surface. The fabric surface is around se smoother and the coefficient of friction of the surface urr smaller, the smaller the surface contour value is The high smoothness of the fabric surface is essential a knitted or warp-knitted fabric which, when viewed with the naked eye, has a fabric-like appearance target.

The following examples serve to illustrate the invention.

Example I.

Polyäthyleni erephthalat with an intrinsic molar viscosity of 0.5 was used to produce a continuous polyester yarn with a titer of 167 dtex / 48 threads by conventional spinning and drawing. The yarn was bottle twisted into a textured yarn. Since "textured polyester yarn was under high pressure gbiuiut uiiu uu * u% .ifi gi.iaii / 11.11 OBMI aui 1.111WI conventional circular knitting machine, a patterned double Jersey having a basis weight of 230g / ^m; and a thickness of 1.03 mm. The double jersey obtained has a porosity of 84% and a surface contour value ve η 9 and has the appearance and the carrying properties (handle) of conventional knitted fabrics.

This double jersey is divided into 7 samples; the 4 samples /. B, C and D were according to the invention under treated the process conditions given in Table 1. A sample remains for comparison (a) untreated, and two samples (b and c) are processed by a method other than that of the invention treated under the conditions given in Table 1. The pressed ones are used for moisture fixation Samples wrapped around a pipe and placed in a closed vessel under the action of steam exposed; Duration, temperature and contact pressure are given in Table 1.

From Table 1 it can be clearly seen that the fabric samples A, B, C and D treated according to the invention are a Porosity of at most 80% and a surface contour value of at most 6, so that this Pressed knitted or knitted fabric is defined as a fabric with a fabric-like appearance and wearing properties (Handle) represents. In comparison, the comparative samples a and c have a greater porosity than 80% and a surface contour value greater than 6; comparative sample b has a surface contour value over 6, while the porosity is a little less than 80%.

Table 1

According to the invention. rehearse
ABC

comparison
away

Press treatment
Temp. (C)
Pressure (bar)

Duration (see)

Moisture fixer.
Temp. (C)
Pressure
Duration (min)

130 130 120 110 20th 15th 10 20th 20th 10 10 20th 130 130 120 110 300 300 500 iOOO 5 10 5 10

no

no

80 ke 3 3 95 90 80 50 2 1

l'orosiliit (%)
Surface contour value
Aiissenen and handle

I. Clear mass (cm Vc ην
Coefficient of friction

Mesh loops

Row of stitches

s)

IrUndungspom. I ' raw I) comparison H 126 C. Λ Β C. 65 ,1 78 0.404 85 50 58 76 3 84 8th 0.601 <) 2 4 5 9 No similarity with Similar wedge mil Woven goods Woven goods 57 208 147 46 65 72 0.364 0.445 0.424 0.344 0.364 0.364 0.424 0.675 0.649 0.424 0.466 0.488

The air permeability was determined according to ASTM D 737-67. The coefficient of friction of the fabric surface

* ^! - -! g. j UaFsCStCi polyester staple fibers were spun separately into yarns of 208 dtex. ] each of the yarns obtained

certainly. The test sample 71 is placed on a plate 72; a weight 73 covered with nylon taffeta is placed on the sample 71; the sample 72 is gradually inclined and the angle θ at which the weight 73 begins to slide on the surface of the test sample 71 is measured; from this the coefficient of friction of the surface is obtained by the equation coefficient of friction (Ms) = tang θ.

Example 2

By means of a conventional spinning and drawing process were made of polyethylene terephthalate with a Intrinsic viscosity of 0.68 polyester staple fibers with a titer of 5.6 dtex and a staple length of 5 cm after dyeing, the polyester staple fibers with dyed wool fibers in Mixing ratios of 40:60, 60:40 and 80:20 parts by weight are mixed. The mixes and the

Table 2

The two-ply yarns obtained were knitted into a patterned double jersey with a basis weight of 240 g / m ² , a porosity of 82% and a surface contour value of 12 on a conventional circular knitting machine.

The mixture of 60 wt .-% polyester fibers and 40 wt .-% wool fibers is used as sample I, the mixture of 80% by weight polyester fibers and 20% by weight wool fibers as sample J, the fabric made from 100% by weight polyester fibers referred to as sample K, and the mixture of 40% polyester fibers and 60% wool fibers as comparative sample g. All samples were at a temperature of 110 ° C under a pressure of 15 bar for 20 s by means pressed in a continuously operating flat press; then at a temperature of 115 ° C Fixed moist under a pressure of 300 mbar for 3 min. The properties of the treated samples are listed in Table 2.

sample
I.

Mixing ratio
Porosity (%)
Surface contour value
Appearance and grip

Air permeability (cmVcm ²
Coefficient of friction

Wales

Row of stitches

s)

60/40 80/20 100/0 40/60 77 51 40 82 5 4th 3 12th similarity with woven fabric no resemblance with woven fabric 65 82 57 155 0.404 0.384 0.364 0.445 0.466 0.445 0.424 0.753

Example 3

60

Using a conventional spinning and drawing process, polyethylene terephthalate with an inherent viscosity of 0.65 was used to produce a multi-ply polyester continuous yarn with a titer of 167 dtex / 48 individual threads Triple Interlook double jersey fabric with a basis weight of 200 g / m ² , a porosity of 90% and a surface contour value of 9 knitted. The jersey fabric obtained had the usual appearance and the usual wearing properties (feel) of knitwear.

This jersey fabric is divided into 7 samples, of which the four samples L, M, N and P of the treatment according to the invention under the conditions given in Tab be subjected. The sample (h) was not treated, the other two samples (i and j) were treated according to other conditions mentioned in Tab. 3

ίο

The pressing was carried out in a dry state in one shown in Table 3. Samples L, M, N and P

continuously operating flat press. Apart from the comparative sample h, the pressed samples were in clamped in a pin frame and fixed dry. The properties of the treated samples are

Table 3

show due to ('τ high surface smoothness and the low porosity has the same pleasant look and feel as a woven one Worsted yarn on.

lirHn (luMj! Sj: cm. samples M. 58 N I ' comparison i j similarity 258 174 I. H with woven fabric Press treatment 120 0.384 110 90 80 240 0.625 0.510 Temp. (C) 130 2 (i 0.424 10 5 no 3 0.675 0.577 Pressure (bar) 30th 20th 30th 40 no 4th 0.577 Duration (s) 20th 0.649 Dry fixation IXO 170 Ui (I 180 ! 40 Temp, f C) 1X0 IO 25th 20th no ¹ ? 10 10 Duration (s) 15th 46 65 75 no 92 88 Porosity (%) 37 4th 5 6th 90 Il 10 Surface contour value 2 Resemblance to Woven goods 9 Appearance and grip " no / 42 73 85 Air permeability (cm '/ cm' ■ s) Coefficient of friction 0.364 0.404 0.445 Wales 0.404 0.445 0.488 Row of stitches For this purpose 2 sheets of drawings

Claims (4)

Claims; 1. A process for the production of clothing fabrics by hot pressing of polyester-containing knitted or knitted goods, characterized in that the goods contain at least 50 wt .-% polyester and the remainder wool and at a temperature between 90 and 130 ⁰ C and at a pressure of 5 to 35 bar is hot-pressed for 5 to 40 s in such a way that it has a porosity of at most 80%, a surface contour value of at most 6 and its thickness is reduced by 5 to 45% 2. The method according to claim 1, characterized in that the hot pressing treatment is carried out at a pressure of 10 to 25 kg / cm ² . 3. The method according to claim 1 or 2, wherein the goods are additionally fixed, characterized in that the goods are then subjected to the hot press treatment at a temperature of 110 to 130 ⁰ C over a period of 2 to 10 min of a moisture fixing treatment at a pressure of 03 is subjected to 1 bar. 4. The method according to claim 1 or 2, wherein the goods are additionally fixed, characterized in that the goods are then subjected to the hot pressing treatment at a temperature of 150 to 200 ⁰ C for a period of 5 to 30 s of a dry fixing treatment.