EP0609159B1 - Filaments, fibres and pigmented yarns for outdoor use - Google Patents

Abstract

The present invention relates to pigmented filaments, fibres, monofilament yarns or multifilament yarns, based on polyamide, having improved stability with respect to degradation by ultraviolet radiation and atmospheric agents. They contain, in particular, from 15 to 100 ppm of copper with respect to the weight of polyamide, in the form of a copper compound, from 800 to 2000 ppm of halogen in the form of a metal halide, and from 40 to 200 ppm of manganese in the form of a manganese compound. They find their application in the form of textile surfaces, in particular flocked surfaces, nonwovens, carpets, for indoor and outdoor use, such as sports pitches, amusement areas, artificial lawns, etc.

Description

The present invention relates to filaments, fibers, mono- or multifilament yarns, cables pigmented on the basis of polyamides, for interior or exterior uses designated as threads below from the description.

In the most frequent applications of polyamide-based yarns and fibers, these do not are not permanently and prolonged subject to the degrading effects of sunlight and weather. However for certain internal and especially external jobs such as sports grounds, playgrounds, stadiums or recreational areas such as lawns synthetic, the floors around swimming pools or even interior coverings such as those of motor cars, resistance to degradation by heat and light must wait for a higher level than for conventional textile jobs such as clothing, or certain jobs furniture.

Likewise, the colored threads must have an unalterable tint over time with respect to light rays.

Various solutions for stabilizing compositions based on polyamides have already been proposed. For example, it is known, according to FR 2 236 889, to prepare compositions for pigmented nylon with improved stability against atmospheric agents and light containing 400 to 600 ppm Cu, based on the weight of nylon and 0.4 to 2.2% by weight of mineral halide, the Cu: halide ratio being between 325: 1 and 1150: 1, optionally in the presence of a phosphorus compound.

However, high proportions of copper cause excessive clogging of the dies due to the formation of gels in the molten polyamide.

Patent DE 2 107 406 describes a stabilization system comprising a copper stearate, manganese acetate and potassium iodide. This system is suitable for stabilizing colorless polyamides, because the colors of the stabilizing system can alter or modify the colors of pigments.

It has now been found that it was possible to obtain filaments, fibers, pigmented yarns, with very good mechanical and color characteristics during exhibitions extended to light rays without causing frost or lowering the characteristics mechanical wires. The filaments, threads and fibers according to the invention simultaneously contain 15 to 100 ppm copper as a copper compound, 800 to 2000 ppm halogen as a metal halide and 50 to 100 ppm manganese as a manganese compound.

Preferably they contain 15 to 50 ppm of copper relative to the weight of polyamide under form of copper salt, preferably acetate or copper iodide; metal halide present in the wires is preferably potassium or sodium iodide, preferably potassium, at a rate of 800 to 2000 ppm of iodine relative to the weight of polyamide and preferably 1000 to 1600 ppm. The manganese compound, preferably manganese acetate, is present at 50 to 100 ppm based on the weight of polyamide.

The present invention also relates to textile surfaces, such as nonwovens, carpet, flocked surfaces usable for indoor and outdoor jobs as described above.

The yarns according to the present invention can have very diverse strand titles according to desired use. In particular, they may have a title for the flocked surfaces. less than 1 dtex up to 40 or 50 dtex. For very stressed surfaces important, very large stranded yarns can be used, for example yarns spun from fibers or monofilaments which can have a unit titer of 40 dtex to 500 or 600 dtex or even more. The same textile surface may also have strands of different titles for obtain particular appearance or touch effects without departing from the scope of the invention. The sons according to the invention can have round, flattened or multilobed shapes depending on the effect sought and intended use.

The term polyamide means polyhexamethylene adipamide (PA 6.6), the polycaproamide (PA 6) as well as copolyamides such as PA 6.6 containing percentages variables in caproamide units, or other units likely to be fixed in the PA chain 6.6 or PA 6 in order to improve certain properties, for example the dyeing properties.

The yarns according to the invention are preferably colored by pigmentation by any means known. A large number of pigments can be used for coloring threads according to the invention. For the applications referred to in the present application, it is generally preferred use pigments introduced in the form of masterbatches capable of resisting light, so that the son thus produced retain sufficient mechanical properties. Such dyes and / or pigments must also be very well dispersed in the yarns and fibers used for the preparation of textile surfaces according to the invention.

The dyes and pigments preferably used according to the present invention are in the form of masterbatches, for example with 25% pigment in polyamide 6, generally in the form of granules. The granules are then mixed, for example in the form solid, by mixing the granules of masterbatch and granules of the polymer to be conformed, in the desired proportions. Polymers preferably containing 0.5 to 2.5% of pigment are obtained.

The heat and light stabilizers are preferably introduced according to any process known, for example in the form of a masterbatch, or in polycondensation, with the monomers according to any process known to those skilled in the art.

Naturally other adjuvants can also be introduced during the polycondensation or in the melt of the polyamide to be conformed; for example oxide of titanium, preferably coated, or any other adjuvant capable of modifying certain properties of the sons obtained.

The yarns according to the present invention are obtained by molten spinning of the polyamide charged with pigments and various light and heat stabilizers, under known conditions of the skilled person.

The cooling conditions are adapted to the strand titer of the filaments: these are generally cooled in air or in a liquid medium when the strand titer is less than 40 - 50 dtex. For higher stranded titles, cooling in a liquid medium is preferable because more efficient. The filaments are then drawn and sized in the usual way, possibly textured according to the desired application.

The yarns pigmented in the bulk of the polymer and protected by various protectors light and heat in the proportions recommended according to the invention must undergo favorably the test carried out using the apparatus known in the trade under the name of Q.U.V-B. (Accelerated Weathering Tester). This device can reproduce in a few days or a few weeks the harmful effects that could occur after months or years of exposure to severe weather. The deteriorations particularly observed are the loss of mechanical qualities, in particular the resistance, and the color alteration.

• sous un rayonnement UV-B à intensité maximale 313 nm et dont le spectre s'étend à des longueurs d'onde 275 nm à 370 nm
• dans des conditions de pluie et humidité par condensation d'eau avec exposition de 4 heures à 60°C (UV B seuls) et 4 heures à 50°C avec condensation d'eau.

The yarns according to the invention have been subjected to accelerated aging:

• under UV-B radiation at maximum intensity 313 nm and whose spectrum extends to wavelengths 275 nm to 370 nm
• in rain and humidity conditions by water condensation with exposure of 4 hours at 60 ° C (UV B only) and 4 hours at 50 ° C with water condensation.

Results : Tenacity :

In the case of headlines (> 100 dtex), we consider that very good results are obtained when the exposure time to lose 50% of the toughness is greater than 900 hours, preferably more than 1100 hours.

In the case of titles with a weaker strand (<100 dtex) the wires are more fragile, and the exposure at the same radiation is only realized during 500 Hours. We then measure the loss of tenacity; the result is considered to be good when it does not exceed 60%.

Coloring :

The coloristic result is considered good when the grading on the gray scale determined visually is approximately 3 - 4 after the number of hours of exposure indicated above. The value of 5 corresponds to the best result, the value of 1 to the most degraded.

In the examples which follow, the pigments used are in the form of masterbatches known under the brand name: Renol GG-AN (green), Renol AN CNW FO2 (yellow), Renol B2G AN (blue). They are manufactured and sold by the Hoechst-Novacrome Company. Masterbatches contain 25% of pigment in PA 6 and are in the form of granules which are then mixed in solid form with the granules of the polymer to be conformed, in the desired proportions, to obtain polyamides containing approximately from 0.5 to 2.5% by weight of pigment.

Example 1

A polyhexamethylene adipamide of relative viscosity 44 (measured on an 8.4% solution by weight by volume of polyamide in 90% formic acid) containing 0.3% by weight of oxide of coated titanium, 100 ppm of Mn (relative to the weight of PA) in the form of Mn acetate, 20 ppm copper as Cu acetate and 1147 ppm iodine as copper iodide, is dried and then melted at 285 ° C. After drying 5.32% of the masterbatch is added to this polymer yellow Renol AN CNW FO2 and 0.62% blue masterbatch Renol AN B2G.

The molten and additive polymer is filtered and then spun through a die comprising 60 orifices, with a diameter of 0.60 mm each.

The filaments are cooled by means of an air blower with a flow rate of 346 m ³ / hour, then sized in the usual way, drawn at a rate of 3.4 X in an aqueous bath maintained at 60 ° C, by passage between two sets of rollers and re-sized. The cables collected in pots are intended for cutting.

The results of the wires (A) according to the invention are recorded in Table 1 below, compared with wires (B) obtained in the manner indicated above and containing as stabilizers, only 20 ppm of copper in the form of acetate and 1147 ppm iodine as potassium iodide.
The wire (C) is obtained according to the process indicated above but does not contain any stabilizer or pigment.
The wire (D) obtained according to the above process contains only the pigments.

The exposures according to the Q UV-B test were carried out over a period of 500 hours and the mechanical characteristics measured before and after exposure.

Color fastness: gray scale rating after exposure of 950 hours according to the QUV-B test: Ex 1 (A) 4/5 (B) 4/5 (VS) --- (D) 4/5

Example 2 :

A polyhexamethylene adipamide of relative viscosity 42 containing 0.3% by weight of oxide coated titanium (LOCR-SM from Sachtleben), 100 ppm manganese in the form manganese acetate, 32 ppm copper in the form of copper iodide and 1530 ppm iodine in form of potassium iodide and copper iodide, is dried and then melted at 289 ° C. Before fusion we add 5.95% by weight of a masterbatch containing 5.32% of Rénol bleu B 2G and 0.63% of Renol AN yellow CN W FO2 from the company Hoechst Novacrome.

The polymer thus added and melted is filtered and spun through a die comprising 48 holes of diameter 0.6 mm each. The filaments are cooled by means of an air blower with a flow rate of 240 m ³ / hour. They are then taken up by successive roller trains and stretched between the first and the second train at a rate of 3.7 X and are simultaneously subjected to heat treatment by water vapor; between the second train and the third train of rollers, the filaments spread out in the form of a sheet undergo a slight relaxation and are then sized by passing through a bath. The cable of filaments obtained, having a moisture content of approximately 30%, is bambooed in the usual way.

The cable obtained is made up of strand title filaments 46.2 dtex, of tenacity 28.3 CN / tex, 45.6 CN / tex breaking stress and 62.8% elongation. The green cable thus obtained, allows the production of flocked surfaces in the usual manner.

The loss of toughness is 50% after 890 hours of exposure to the Q UV-B test.

Color stability is good: 4/5 on the gray scale after exposure of 1000 hours.

The flocked surfaces thus produced are perfectly suited for outdoor uses described above, with regard to both mechanical characteristics and color.

Examples 3 to 7

Several compositions are prepared based on hexamethylene adipamide containing light and heat stabilizers as well as pigments and 0.3% of coated titanium oxide as indicated in Table 2 below: Ex. VR Stabilizers Masterbatch containing the pigments 3 54 - Mn: 50 ppm (acetate) 6.2% Renol AN CNW FO2 (yellow)
2.8% Renol GG AN (green) (masterbatch) - Iodine: 1147 ppm (K iodide) - Cu: 20 ppm (Cu acetate) 4 54 - Mn: 50 ppm (acetate) 4.8% Renol HN CNW FO2 (yellow)
0.8% Renol B 2G AN (blue) - Iodine: 1147 ppm (K iodide) - Cu: 20 ppm (Cu acetate) 5 54 - Mn: 50 ppm (acetate) 4.8% Renol HN CNW FO2 (yellow)
0.52% Renol B 2G AN (blue)
0.08% carbon black - Iodine: 1147 ppm (K iodide) - Cu: 20 ppm (Cu acetate) 6 comparison 50 - Mn: 0 6.2% Renol HN CNW FO2 (yellow)
2.8% Renol GG AN -Iodine: 1147 ppm (K iodide) - Cu: 20 ppm (Cu acetate) 7 comparison 42 Control without stabilizer or pigment

The additive polymer is melted at 295 ° C. then filtered and spun through a die comprising 42 0.4 mm diameter holes each. Monofilaments leaving the sector after a short passage in the air are cooled in an aqueous cooling tank. They are then taken up on rollers, and generally arranged in a sheet. they are stretched for the first time between two trains of rolls keeping them in the form of a sheet at a rate of 3.2 X while passing in a first oven then stretched a second time while passing through a second oven maintained at high temperature, then heat treated in a third oven in which they undergo a relaxation. After passing over a last set of rollers, the monofilaments are sized then rewound by any known means, in the form of reels.

The tests were carried out under the conditions gathered in table 3 below. Ex. T ° C average melting T ° C ovens Draw rate Relaxation% Diameter 1/100 mm Title dtex 1st 2nd 3rd 1st 2nd 3 295 140 180 190 3.2 3.8 5 12.1 129 4 295 130 160 170 3.2 3.5 5 11.9 125 5 295 130 160 170 3.2 3.5 5 12 129 6 295 140 180 190 3.2 3.8 5 12.1 129 comparative 7 295 130 160 170 3.2 3.8 5 11.8 122 comparative

The exposure results according to the QUV-B test are summarized in Table 4 below. Ex. NC breaking force Elongation% Withdrawal EB% Breaking toughness CN / tex Nb of hours for a loss of tenacity of 50% Gray scale rating 950 hours QUV-B 3 639 46.5 4.5 49.5 930 3 4 457 72.6 3.2 39.8 > 1200 4 5 465 64.7 3.1 36 1400 4 - 5 6 685 46.3 4.7 53.1 790 3 comparative 7 488 68.3 3.3 40 315 - comparative

Claims (6)

1. Pigmented filaments, fibres and single-filament or multifilament yarns which are based on polyamide and have improved stability to degradation by ultraviolet radiation and atmospheric agents, characterized in that they comprise:

   from 15 to 100 ppm, relative to the weight of polyamide, of copper in the form of a copper compound,

   from 800 to 2000 ppm of halogen, relative to the weight of polyamide, in the form of a metal halide,

   from 50 to 100 ppm of manganese, relative to the weight of polyamide, in the form of a manganese compound.
2. Pigmented filaments, fibres and single-filament or multifilament yarns according to Claim 1, characterized in that the copper compound is copper acetate or copper iodide.
3. Pigmented filaments, fibres and single-filament or multifilament yarns according to Claims 1 and 2, characterized in that the copper is present in a proportion of from 15 to 50 ppm.
4. Pigmented filaments, fibres and single-filament or multifilament yarns according to Claim 1, characterized in that the metal halide is potassium bromide or iodide.
5. Pigmented filaments, fibres and single-filament or multifilament yarns according to Claims 1 and 4, characterized in that potassium iodide is present in a proportion of from 1000 to 1600 ppm of iodine.
6. Textile surfaces, nonwovens, carpets and flock surfaces comprising the filaments, yarns and fibres according to Claims 1 to 5.