POLYAMIDE COMPOSITION WHICH IS DYED IN BLACK, PRODUCTION AND USE THEREOF

Abstract

A black-colored polyamide composition is provided which comprises a chromium-containing azo dye in the form of a chromium complex and carbon black, and also glass fibers. Production of this polyamide composition and use thereof for the production of black-colored laser-inscribable polyamide moldings are also provided.

Claims

1. A polyamide composition comprising a) from 34.98 to 89.98% by weight of at least one synthetic polyamide as component A and b) from 0.01 to 1.0% by weight of a chromium complex dye selected from the compounds of the formulae A1), A2) and A3) and mixtures of two or three of these compounds ##STR00002## as component B, c) from 0.01 to 1% by weight of carbon black as component C, d) from 10 to 65% by weight of glass fibers as component D, e) from 0 to 50% by weight of other additional substances as component E, where the quantities stated, which give a total of 100% by weight, are based on the entire composition and the composition comprises at most 0.05% by weight of nigrosin.

2. The polyamide composition according to claim 1, wherein the composition comprises at most 0.03% by weight of nigrosin.

3. The polyamide composition according to claim 1, wherein the composition comprises, alongside components B and C, no other black-coloring dyes or pigments.

4. The polyamide composition according to claim 1, wherein the quantity of components C and D respectively and mutually independently is from 0.03 to 0.5% by weight.

5. The polyamide composition according to claim 1, wherein lubricants and heat stabilizers are used as component E in quantities of respectively from 0.05 to 1.0% by weight, based on the entire composition.

6. The polyamide composition according to claim 1, where the polyamide is selected from PA 4, PA 5, PA 6, PA 7, PA 8, PA 9, PA 10, PA 11, PA 12, PA 46, PA 66, PA 666, PA 69, PA 610, PA 612, PA 96, PA 99, PA 910, PA 912, PA 1212, PA 6.T, PA 9.T, PA 8.T, PA 10.T, PA 12.T, PA 6.I, PA 8.I, PA 9.I, PA 10.I, PA 12.I, PA 6.T/6, PA 6.T/10, PA 6.T/12, PA 6.T/6.I, PA 6.T/8.T, PA 6.T/9.T, PA 6.T/10T, PA 6.T/12.T, PA 12.T/6.T, PA 6.T/6.I/6, PA 6.T/6.I/12, PA 6.T/6.I/6.10, PA 6.T/6.I/6.12, PA 6.T/6.6, PA 6.T/6.10, PA 6.T/6.12, PA 10.T/6, PA 10.T/11, PA 10.T/12, PA 8.T/6.T, PA 8.T/66, PA 8.T/8.I, PA 8.T/8.6, PA 8.T/6.I, PA 10.T/6.T, PA 10.T/6.6, PA 10.T/10.I, PA 10T/10I/6.T, PA 10.T/6.I, PA 4.T/4.I/46, PA 4.T/4.I/6.6, PA 5.T/5.I, PA 5.T/5.I/5.6, PA 5.T/5.I/6.6, PA 6.T/6.I/6.6, PA MXDA.6, PA IPDA.I, PA IPDA.T, PA MACM.I, PA MACM.T, PA PACM.I, PA PACM.T, PA MXDA.I, PA MXDA.T, PA 6.T/IPDA.T, PA 6.T/MACM.T, PA 6.T/PACM.T, PA 6.T/MXDA.T, PA 6.T/6.I/8.T/8.I, PA 6.T/6.I/10.T/10.I, PA 6.T/6.I/IPDA.T/IPDA.I, PA 6.T/6.I/MXDA.T/MXDA.I, PA 6.T/6.I/MACM.T/MACM.I, PA 6.T/6.I/PACM.T/PACM.I, PA 6.T/10.T/IPDA.T, PA 6.T/12.T/IPDA.T, PA 6.T/10.T/PACM.T, PA 6.T/12.T/PACM.T, PA 10.T/IPDA.T, PA 12.T/IPDA.T and copolymers and mixtures thereof.

7. The polyamide composition according to claim 1, where component E comprises at least one polymer selected from: homo- or copolymers which comprise, in copolymerized form, at least one monomer selected from C.sub.2-C.sub.10 monoolefins, for example ethylene or propylene, 1,3-butadyene, 2-chloro-1,3-butadyene, vinyl alcohol and its C.sub.2-C.sub.10-alkyl esters, vinyl chloride, vinylidene chloride, vinylidene fluoride, tetrafluoroethylene, glycidyl acrylate, glycidyl methacrylate, acrylates and methacrylates having alcohol components of branched and unbranched C.sub.1-C.sub.10-alcohols, vinyl aromatics, for example styrene, acrylonitrile, methacrylonitrile, ,-ethylenically unsaturated mono- and dicarboxylic acids, and maleic anhydride; homo- and copolymers of vinyl acetals; polyvinyl esters; polycarbonates (PC); polyesters, for example polyalkylene terephthalates, polyhydroxyalkanoates (PHA), polybutylene succinates (PBS), polybutylene succinate adipates (PBSA); polyethers; polyetherketones; thermoplastic polyurethanes (TPU); polysulfides; polysulfones; polyether sulfones; cellulose alkyl esters; and mixtures thereof.

8. (canceled)

9. A molding produced from a polyamide molding composition according to claim 1.

10. A process for the production of a polyamide composition as defined in claim 1, where at least one synthetic polyamide A, at least one chromium complex dye B, carbon black C and optionally other additives are mixed with one another with heating to a temperature in a range from 160 to 340 C.

11. The polyamide composition according to claim 2, wherein the composition comprises at most 0.01% by weight nigrosin.

12. The polyamide composition according to claim 11, wherein the composition comprises no nigrosin.

13. The polyamide composition according to claim 3, wherein the composition comprises, alongside components B and C, no other dyes or coloring pigments.

14. The polyamide composition according to claim 4, wherein the quantity of components C and D respectively and mutually independently is from 0.05 to 0.3% by weight.

15. The polyamide composition according to claim 6, where the polyamide is selected from PA 6, PA 66, PA 666 and PA 12.

16. The polyamide composition according to claim 15, where the polyamide is PA 66.

17. The polyamide composition according to claim 7, where component E comprises at least one polymer selected from styrene copolymers, polyalkyl (meth)acrylates, polycarbonates and mixtures thereof.

Description

EXAMPLES

[0159] The following raw materials were used: [0160] Nylon-6,6: Ultramid A27 from BASF SE, melting point: 264 C., viscosity number (0.5% in 96% H.sub.2SO.sub.4): 150 cm.sup.3/g [0161] Nylon-6: Ultramid B27 from BASF SE, melting point: 222 C., viscosity number (0.5% in 96% H.sub.2SO.sub.4): 150 cm.sup.3/g [0162] Glass fiber: 3B-DS1125, producer: 3B-FIBREGLASS S.P.R.L., average diameter: 10.5 m, length: 4 mm [0163] Glass fiber: NEG-T249H, producer: NIPPON ELECTRIC GLASS (MALAYSIA) SDN. BHD., average diameter: 10.5 m, length: 3 mm [0164] Nigrosin/Solvent Black 7: producer: COLLOIDS LTD. [0165] Solvent Black 28: Oracet BK 045, producer: BASF SE [0166] Carbon black (Special Black 4): producer: Orion Engineered Carbons GmbH [0167] Heat stabilizer: Cul/KI in a molar ratio of 1:4 [0168] Lubricant: EBS, producer: Lonza Cologne GmbH

[0169] The ingredyents stated in Table 1 below were premixed for ten minutes in a tumbling mixer and then extruded and pelletized by way of a twin-screw extruder with diameter 25 mm and L/D ratio 44 at 300 C. barrel temperature. For this, the natural-color polyamide pellets were predried in a drying oven at 100 C. for four hours to give less than 0.1% moisture content. The resultant pellets were injection-molded at a melt temperature of 300 C. to give plaques of thickness 2 mm measuring 6060 mm, and the product was assessed visually and also by technical testing. Mechanical properties were determined in accordance with DIN ISO 527 and, respectively, 179-2/1 eU and, respectively, 179-2/1 eAf in the version valid in 2016.

TABLE-US-00001 TABLE 1 Com- Com- Com- In- Com- Com- Com- In- pari- pari- pari- ventive pari- pari- pari- ventive Composition son 1 son 2 son 3 ex. 1 son 4 son 5 son 6 ex. 2 PA 66 (ULT. A27) 63.8 64.2 64.4 64.3 PA 6 (ULT. B27) 69.2 68.1 69 69 Glass fiber (3B - DS1125) 35 35 35 35 Glass fiber (NEG - T249H) 30 30 30 30 Solvent Black 7 (nigrosin) 0.76 0.2 0 0 0.3 0.4 0.2 Solvent Black 28 (Oracet 0 0 0 0.1 0 0 0 0.1 BK 045) Carbon black (Special 0 0.1 0.1 0.1 0 1 0.1 0.1 Black 4) Heat stabilizer (CuI/KI) 0.13 0.13 0.13 0.13 0.28 0.28 0.3 0.3 Lubricant (EBS) 0.35 0.35 0.35 0.35 0.2 0.2 0.2 0.2

[0170] The flow spiral tests were carried out by a method internal to BASF where the material is charged by way of an injection molding machine at constant temperature and constant injection pressure to a spiral mold until the melt freezes. Flow path length can then be directly read from the resultant sample.

[0171] A Veeco NT9300 white-light interferometer was used to measure surface roughness (mean roughness value R.sub.a, root-mean-square roughness value R.sub.q and mean roughness depth R.sub.z). Glass was measured in accordance with DIN ISO 8254-1 with handheld micro gloss 75 equipment from BYK-Gardner GmbH, Geretsried. The highest gloss value from 20 individual measurements was used.

[0172] The laser contrast value was determined in accordance with DIN 66236. Laser inscription can by way of example be achieved with a FOBA DP50 laser, which is a diode-pumped Nd:YAG laser with wavelength 1064 nm or 532 nm. The typical laser power rating is 50 W. The luminance value can by way of example be determined with a Minolta LS-110 luminance meter. This is an SLR spot luminance tester for testing spot luminance of light sources and of surfaces. Measurement angle is and observation angle is 9. The optical system used is an 85 mm f/2.8 objective with SLR observer system. The scattered-light factor is less than 1.5%.

[0173] The contrast value describes the intensity difference between the brightest and darkest points of a KTE grid and of the substrate. The contrast values are calculated by using the maximal and minimal luminance values determined for inscription and substrate.

[0174] A Minolta LS-110 luminance meter was used to determine the luminance value.

[0175] Table 2 below collates the test results.

[0176] From the results it is apparent that good impact resistance together with good luminance and gloss values were determined at the same time as high laser contrast values only for the combination of the invention: Solvent Black 28 and carbon black.

TABLE-US-00002 TABLE 2 Comparison Comparison Comparison Inventive Connparison Unit DIN ISO 1 2 3 ex. 1 4 Product features Density g/cm.sup.3 53479 1183 1.411 1.411 1.411 1.411 1.350 VN (0.005 g/ml in H.sub.2SO.sub.4) cm.sup.3/g 53727 307 144 156 144 152 151 Mechanical properties (dry) Tensile modulus of elasticity MPa 527 11287 11330 11400 11405 9481 Tensile stress at break MPa 527 208 208 190 199 182 Tensile strain at break % 527 3.0 3.3 2.6 3.4 4.2 Charpy impact resistance kJ/m.sup.2 179-2/1eU 90 89 73 89 98 Charpy notched impact kJ/m.sup.2 179- 11.7 11.4 9.7 10.7 12.9 resistance 2/1eAf Other properties 2 mm flow spiral cm 78 69 71 70 75 (Injection pressure 100 bar) 2 mm flow spiral cm 105 88 98 96 95 (Injection pressure 150 bar) Surface roughness 0.8/1.8/73 1.2/2.2/77 3.0/4.2//103 1.4/2.5/83 (R.sub.a/R.sub.q/R.sub.z) 75 gloss measurement 8254-1 76.7 75.4 71.4 74.6 93.2 (KTE) laser contrast value 3.8 11.8 19.8 17.5 7.4 Laser contrast value 66236 73.3 91.5 94.9 94.3 86.5 Luminance value (max. 30 106 257 210 37 brightness of inscription in cd/m.sup.2)