Transparent polyamide excellent in weatherability

Abstract

To provide a polyamide molding composition excellent in weatherability.SOLUTION: A polyamide molding composition includes a component A of 85-99.85 wt.% consisting of polyamide A1 or the mixture of polyamides A1 and A2. A1 is at least one amorphous or fine crystallite polyamide including more than 60 mol% of a monomer having only an aliphatic structure unit on the basis of the total amount of the monomer; A2 is at least one acyclic aliphatic polyamide; the total of the components A1 and A2 is the component A of 100 wt.%. The polyamide molding composition has the maximum 32 of a color brightness L*determined according to DIN EN ISO 11664-4:2020 in the CIELAB color space of a plate having a size of 60×60×2 mm; and the polyamide A1 has at least a transparency of 88% and a haze of the maximum 5% when determined according to ASTM-D 1003-21 on the plate having a size of 60×60×2 mm in each case.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to a black polyamide molding compound based on a transparent polyamide having good weather resistance, molded articles produced therefrom, and their uses. [Background technology]

[0002] Due to their excellent optical and mechanical properties, the use of amorphous or microcrystalline polyamide molded compounds is widespread in applications in fields such as automotive parts, electronic equipment, optical components, screens, housings, and visible surfaces.

[0003] Black molded products are used in many applications in the technical field, and have the advantage of appearing like so-called piano lacquer in the visible range, that is, combined with a high gloss, give the impression of deep, expansive blackness. In conventional technology, the colorants used for blackening are mainly carbon black, especially fine particles, so-called UV carbon black.

[0004] background For example, U.S. Patent No. 5,945,469 describes a polyamide composition comprising a hindered amine and a phosphite or phosphonite, in addition to polyamides and reactive polysiloxanes. The black coloration of the molded compound is achieved by finely segmented carbon black having an absorption coefficient greater than 400. Such molded compounds are said to exhibit reduced color change after weathering.

[0005] U.S. Patent No. 6,265,472 relates to a filler-containing polyamide molded compound with improved weather resistance, which is colored black with carbon black and copper phthalocyanine dyes.

[0006] Japanese Patent Publication No. 2008-266434 relates to a black polyamide molded compound that can be joined to a suitable substrate by laser welding and articles formed therefrom. Laser welding is made possible by replacing the coloring agent carbon black with, for example, a mixture of anthraquinone and perylene dye. However, the weather resistance of these laser-weldable molded compounds is not at all competitive with the conventional molded compounds that, while otherwise identical, contain carbon black as a coloring agent.

[0007] International Publication No. 2017 / 144276 also relates to laser welding of pure black polyamide compositions. However, no information on weather resistance is provided.

[0008] International Publication No. 2012 / 080398 relates to transparent polymer compositions based on polycarbonate colored with organic dyes. The objective is to obtain a polycarbonate molding compound that is colored gray as neutrally as possible and has good heat resistance and weather resistance. This is achieved by special selection and combination of organic colorants, although carbon black is always used in the mixed color.

[0009] Therefore, conventional technologies do not describe any molded compounds that are based on transparent polyamide, colored black without using carbon black, and have better weather resistance than compounds colored with carbon black. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] U.S. Patent No. 5,945,469 [Patent Document 2] U.S. Patent No. 6,265,472 [Patent Document 3] Japanese Patent Publication No. 2008-266434 [Patent Document 4] International Publication No. 2017 / 144276

Patent Document 5

Summary of the Invention

[0011] The present invention provides a polyamide molding compound based on a transparent polyamide characterized by a piano black appearance. The polyamide molding compound should have a maximum color lightness L of 32 when measured in the CIELAB color space of a 60×60×2 mm sheet according to DIN EN ISO 11664-4:2020 * and should have high gloss and good weather resistance. In particular, the gloss should be reduced only slightly under weathering at an angle of 60°, and the color lightness difference ΔL * and color distance ΔE determined by comparing with an unweathered specimen in the CIELAB color space of a 60×60×2 mm plate according to DIN EN ISO 11664-4:2020 should be small. In this regard, the weather resistance should be significantly improved compared to polyamide molding compounds in which the colorant carbon black is used alone or in combination with other colorants.

[0012] Specifically, preferably, the polyamide molding compound according to the present invention has a maximum color lightness difference ΔL of 3 or less, a maximum color difference ΔE of 4 or less, and a change in gloss at 60° of less than 20% after 1000 hours of weathering according to DIN EN ISO 4892-2:2013, and the unweathered sample functions as a reference for the change in gloss ΔL * or ΔE * This problem is solved by the polyamide molding composition according to claim 1, which contains or preferably consists of the following components:

[0013] 85 to 99.85% by weight of component A, where component A consists of polyamide A1 or a mixture of polyamide A1 and A2, 85 to 99.85% by weight of component A, where component A consists of polyamide A1 or a mixture of polyamide A1 and A2, A1 is at least one amorphous or microcrystalline polyamide containing more than 60 mol% of monomers having only aliphatic structural units based on the total amount of monomers, A2 is at least one acyclic aliphatic polyamide, The sum of components A1 and A2 equals 100% by weight of component A, 0.05 to 2.0% by weight of at least one coloring agent B, 0.10 to 3.0% by weight of at least one stabilizer C, 0 to 10% by weight of additive D other than A, B, and C, The sum of the weight percentages of components A through D equals 100% by weight, and the polyamide molded composition does not contain carbon black or nigrosine. The color lightness L of a plate with dimensions of 60 x 60 x 2 mm, as determined according to DIN EN ISO 11664-4:2020 in the CIELAB color space. * The maximum is 32, and the polyamide A1, in a plate of dimensions 60 × 60 × 2 mm, has a transparency of at least 88%, preferably at least 90%, and a haze of up to 5%, preferably up to 3%, respectively, according to ASTM-D1003-21.

[0014] Advantageous embodiments of the polyamide molding composition according to the present invention are given in dependent claims 2 to 13. Furthermore, according to claim 14, the present invention relates to a polyamide molding composition according to the present invention, preferably a molded article comprising the same. Furthermore, according to claim 15, the present invention relates to the use of a colorant according to the present invention in a black polyamide molding composition based on a transparent polyamide in order to improve weather resistance. [Modes for carrying out the invention]

[0015] Definition of Terms Notation and abbreviations for polyamides and their monomers For the purposes of this invention, the term "polyamide" (abbreviated as PA) is understood to be a general term, and this includes homopolyamides and copolyamides. The selected spellings and abbreviations for polyamides and their monomers correspond to those specified in the DIN EN ISO standard 16396-1:2015. The abbreviations used therein are used below as synonyms for the IUPAC names of the monomers. In particular, the following monomer abbreviations can be obtained: MACM for bis(4-amino-3-methyl-cyclohexyl)methane (also known as 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, CAS number 6864-37-5), PACM for bis(4-aminocyclohexyl)methane (also known as 4,4'-diaminodicyclohexylmethane, CAS number 1761-71-3), TMDC for bis(4-amino-3,5-dimethylcyclohexyl)methane (also known as 3,3',5,5'-tetramethyl-4,4'-diaminodicyclohexylmethane, CAS number 65962-45-0), T for terephthalic acid (CAS number 100-21-0), I for isophthalic acid (CAS number 121-95-5), and BAC for 1,4-bis(aminomethyl)cyclohexane (CAS number 2549-93-1).

[0016] amount The polyamide molding composition according to the present invention contains components A to D, or preferably consists only of components A to D. The requirement is that the sum of components A to D is 100% by weight. The specified range of amounts of individual components A to D should be understood to mean that arbitrary amounts of each individual component can be selected within the specified range, as long as the strict requirement that the sum of all components A to D is 100% by weight is met.

[0017] Amorphous or microcrystalline polyamides Amorphous or microcrystalline polyamides exhibit a heat of fusion of preferably 25 J / g or less, particularly preferably 22 J / g or less, and most preferably 0 to 20 J / g, at a heating rate of 20 K / min, as measured by dynamic differential scanning calorimetry (DSC) according to DIN EN ISO 11357-3 (2018).

[0018] In addition to a glass transition temperature, microcrystalline polyamides also have a melting point. However, they have crystallites of very small size, and therefore sheets made from them with a thickness of 2 mm are still transparent, i.e., they have a form in which their light transmittance is at least 90% and their haze is at most 3%, as measured according to ASTM D 1003-21(2021).

[0019] Compared to microcrystalline polyamides, amorphous polyamides have no heat of fusion or only a very low, almost undetectable heat of fusion. In dynamic differential calorimetry according to DIN EN ISO 11357-3 (2018) at a heating rate of 20 K / min, amorphous polyamides exhibit a heat of fusion of preferably up to 5 J / g, particularly preferably up to 3 J / g, and most preferably 0 to 1 J / g. Because amorphous polyamides are amorphous, they have no melting point.

[0020] For the purposes of the present invention, the semicrystalline polyamide is a polyamide having a heat of fusion of preferably greater than 25 J / g, particularly preferably at least 30 J / g, and most preferably at least 35 J / g, in dynamic differential calorimetry according to DIN EN ISO 11357-3 (2018) at a heating rate of 20 K / min. A sheet made of semicrystalline polyamide having a thickness of 2 mm is not transparent, i.e., its light transmittance is less than 90%, and / or its haze is greater than 3%, in either case measured according to ASTM D 1003-21 (2021).

[0021] Transparent polyamide For the purposes of the present invention, a transparent polyamide exists if its light transmittance, measured in a 2 mm thick sheet according to ASTM D 1003-21(2021), is at least 88%, preferably at least 90%, and its haze is at most 5%, preferably at most 3%. Where transparent polyamide is referred to in the following disclosure, it always means amorphous or microcrystalline polyamide that satisfies the above definitions with respect to transparency and heat of fusion.

[0022] Components A, A1, and A2 The polyamide molding composition according to the present invention contains 85 to 99.85% by weight of component A, based on the total of components A to D, and component A consists of polyamide A1 or a mixture of polyamide A1 and A2. The weight percentage of components A1 and A2 together is 100% by weight of component A, and the content of polyamide A1 in component A is preferably at least 50% by weight. Component A1 is at least one transparent polyamide containing at least 60 mol% of monomers having only aliphatic structural units, based on the total amount of monomers in polyamide A1. A1 is amorphous or microcrystalline. Component A preferably consists of 50 to 95% by weight of polyamide A1 and 5 to 50% by weight of polyamide A2, particularly preferably 60 to 85 wt% of polyamide A1 and 15 to 40 wt% of polyamide A2, and particularly preferably 65 to 80 wt% of polyamide A1 and 20 to 35 wt% of polyamide A2.

[0023] A2 is at least one acyclic aliphatic polyamide. Polyamide A2 is preferably selected from the group consisting of PA11, PA12, PA1010, PA1016, PA610, PA612, PA614, PA616, PA66, PA6, PA6 / 12, and mixtures thereof.

[0024] At least 60 mol% of the monomers having only aliphatic structural units may be aliphatic diamines, aliphatic dicarboxylic acids, aliphatic lactams, or aliphatic aminocarboxylic acids. Therefore, polyamide A1 consists of at least 60 mol% monomers having only aliphatic structural units and up to 40 mol% monomers containing aromatic structural units.

[0025] Furthermore, the requirement applies that the transparent polyamide A1 has a transparency of 88% or more, preferably 90% or more, and a haze of 5% or less, preferably 3% or less.

[0026] According to a preferred embodiment of the present invention, component A1 is amorphous.

[0027] According to a preferred embodiment of the present invention, the proportion of component A is in the range of 91 to 99.72% by weight, particularly preferably 94.7 to 99.55% by weight, based on the sum of components A to D in each case.

[0028] According to a more preferred embodiment of the present invention, the transparent polyamide A1 is composed of the following monomers. Based on the total amount of a-A1 diamines, 15 to 100 mol% alicyclic diamines Based on the total amount of b-A1 diamines, 0 to 85 mol% open-chain aliphatic diamines Based on the total amount of c-A1 dicarboxylic acid, 20 to 100 mol% aliphatic dicarboxylic acid Based on the total amount of d-A1 dicarboxylic acid, 0 to 80 mol% aromatic dicarboxylic acid Based on the total amount of e-A1 from monomer a-A1, aliphatic lactams and / or aliphatic aminocarboxylic acids having 6 to 12 carbon atoms are available in 0 to 40 mol%. In this case, the total of diamine a-A1 and b-A1 is 100 mol%, The total amount of dicarboxylic acid c-A1 and d-A1 is 100 mol%.

[0029] According to another preferred embodiment of the present invention, transparent polyamide A1 contains monomers having only aliphatic structural units in an amount of at least 63 mol%, preferably at least 68 mol%, particularly at least 70 mol%, particularly preferably 60 to 100 mol%, or 63 to 100 mol%, or 68 to 100 mol%, based on the total amount of monomers. The total amount of monomers is the sum of components a-A1 to e-A1, and the content of monomers having only aliphatic structural units is the sum of components a-A1, b-A1, c-A1, and e-A1.

[0030] Another preferred embodiment of the present invention is that at least one polyamide A2 is selected from the group consisting of PA11, PA12, PA1010, PA1016, PA610, PA612, PA614, PA616, PA66, PA6, PA6 / 12, and mixtures thereof.

[0031] In another preferred embodiment of the present invention, the alicyclic diamine a-A1 is selected from the group consisting of bis-(4-amino-3-methylcyclohexyl)methane (MACM), bis-(4-aminocyclohexyl)methane (PACM), bis-(4-amino-3-ethylcyclohexyl)methane, bis-(4-amino-3,5-dimethylcyclohexyl)methane, 2,6-norbornanediamine (2,6-bis-(aminomethyl)norbornane), 1,3-diaminocyclohexane, 1,4-diaminocyclohexanediamine, isophoronediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane (BAC), 2,2-(4,4'-diaminodicyclohexyl)propane, and mixtures thereof. Particularly preferred alicyclic diamine a-A1 is selected from the group consisting of bis-(4-amino-3-methylcyclohexyl)methane (MACM) and bis(4-amino-cyclohexyl)methane (PACM) and mixtures thereof.

[0032] According to another preferred embodiment, diamine b-A1 is selected from the group consisting of 1,4-butanediamine, 1,5-pentanediamine, 2-methyl-1,5-pentanediamine, hexanediamine, particularly 1,6-hexanediamine, 2,2,4-trimethyl-1,6-hexamethylenediamine, 2,4,4-trimethyl-1,6-hexamethylenediamine, nonanediamine, particularly 1,9-nonanediamine, 2-methyl-1,8-octanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,13-tridecanediamine, 1,14-tetradecanediamine, 1,18-octadecanediamine, and mixtures thereof. A diamine having 6 to 10 carbon atoms, particularly open-chain aliphatic diamine b-A1 selected from the group consisting of 1,6-hexanediamine, 1,9-nonanediamine, 1,10-decanediamine, and mixtures thereof, is especially preferred.

[0033] Another preferred embodiment of the present invention is that the aliphatic dicarboxylic acid c-A1 is selected from the group consisting of 1,6-hexanedioic acid, 1,9-nonanedioic acid, 1,10-decanedioic acid, 1,11-undecanedioic acid, 1,12-dodecanedioic acid, 1,13-tridecanedioic acid, 1,14-tetradecanedioic acid, 1,16-hexadecanedioic acid, 1,18-octadecanedioic acid, 1,3-cyclopentanediic acid, 1,3-cyclohexanediic acid, 1,4-cyclohexanediic acid, 2,3-norbornanediic acid, 2,6-norbornanediic acid, and mixtures thereof. Dicarboxylic acids having 6 to 12 carbon atoms, particularly aliphatic dicarboxylic acid c-A1 selected from the group consisting of 1,6-hexanedioic acid, 1,10-decanedioic acid, 1,12-dodecanedioic acid, and mixtures thereof.

[0034] According to a more preferred embodiment of the present invention, aromatic dicarboxylic acid d-A1 is selected from the group consisting of terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid (NDA), particularly 1,5-naphthalenedicarboxylic acid and 2,6-naphthalenedicarboxylic acid, biphenyldicarboxylic acid, particularly albiphenyl-2,2'-dicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 3,3'-diphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid and 4,4'-diphenylsulfondicarboxylic acid, 1,5-anthracenedicarboxylic acid, p-terphenylene-4,4''-dicarboxylic acid and 2,5-pyridinedicarboxylic acid and mixtures thereof. Particularly preferred aromatic dicarboxylic acid d-A1 is selected from the group consisting of terephthalic acid, isophthalic acid and mixtures thereof.

[0035] According to another preferred embodiment of the present invention, the lactam and / or α,ω-aminocarboxylic acid is e-A1 selected from the group consisting of caprolactam (CL), α,ω-aminocaproic acid, α,ω-aminoheptanoic acid, α,ω-aminooctanoic acid, α,ω-aminononanoic acid, α,ω-aminodecanoic acid, α,ω-aminoundecanoic acid (AUA), laurolactam (LL), and α,ω-aminododecanoic acid (ADA), and particularly preferably caprolactam, α,ω-aminocaproic acid, laurolactam, α,ω-aminoundecanoic acid, and α,ω-aminododecanoic acid, as well as mixtures thereof.

[0036] In another preferred embodiment of the present invention, alicyclic diamine a-A1 is selected from the group consisting of bis-(4-amino-3-methylcyclohexyl)methane, bis-(4-aminocyclohexyl)methane, bis-(4-amino-3,5-dimethylcyclohexyl)methane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane and mixtures thereof, and / or diamine b-A1 is selected from the group consisting of 1,6-hexanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine and mixtures thereof, and / or aliphatic dicarboxylic acid c-A1 is 1,6-hexanedioic acid, 1,9-nonanediic acid, 1,10-decanediic acid, The component is selected from the group consisting of 1,11-undecanedioic acid, 1,12-dodecanedioic acid, 1,13-tridecanedioic acid, 1,14-tetradecanedioic acid, 1,16-hexadecanedioic acid, 1,18-octadecanedioic acid, and mixtures thereof, and / or aromatic dicarboxylic acid d-A1 is selected from the group consisting of terephthalic acid, isophthalic acid, 1,5-naphthalenedicarboxylic acid, and 2,6-naphthalenedicarboxylic acid, and mixtures thereof, and / or lactam and / or α,ω-aminocarboxylic acid e-A1 is selected from the group consisting of caprolactam (Cl), α,ω-aminocaproic acid, α,ω-aminoundecanoic acid (AUA), laurin lactam (LL), and α,ω-aminododecanoic acid (ADA), and mixtures thereof. Particularly preferably, all of the above selection lists for components a-A1 to e-A1 are selected simultaneously.

[0037] Particularly preferred diamine a-A1 is selected from the group consisting of bis-(4-amino-3-methylcyclohexyl)methane (MACM) and bis(4-aminocyclohexyl)methane (PACM) and mixtures thereof; open-chain aliphatic diamine b-A1 is selected from the group consisting of 1,6-hexanediamine, 1,9-nonanediamine, 1,10-decanediamine and mixtures thereof; aliphatic dicarboxylic acid c-A1 is selected from the group consisting of 1,6-hexanedioic acid, 1,10-decanedioic acid, 1,12-dodecanedioic acid and mixtures thereof; aromatic dicarboxylic acid d-A1 is selected from the group consisting of terephthalic acid, isophthalic acid and mixtures thereof; and lactam and / or aminocarboxylic acid e-A1 is selected from the group consisting of caprolactam, aminocaproic acid, aminocaproic acid, aminocaproic acid, aminoundecanoic acid, laurin lactam, and aminododecanoic acid and mixtures thereof.

[0038] According to another preferred embodiment of the invention, the polyamide A1 is PA MACM9, PA MACM10, PA MACM11, PA MACM12, PA MACM13, PA MACM14, PA MACM15, PA MACM16, PA MACM17, PA MACM18, PA MACM36, PA PACM9, PA PACM10, PA PACM11, PA PACM12, PA PACM13, PA PACM14, PACM15, PA PACM16, PACM17, PA PACM18, PA PACM36, PA TMDC9, PA TMDC10, PA TMDC11, PA TMDC12, PA TMDC13, PA TMDC14, PA TMDC15, PA TMDC16, PA TMDC17, PA TMDC18, PA TMDC36, PA MACM10 / 1010, PA MACM10 / PACM10, PA MACM12 / 1012, PA MACM14 / 1014, PA PACM10 / 1010, PAPACM12 / 1012, PA PACM14 / 1014, PA MACM12 / PACM12, PA MACM14 / PACM14, PA MACMI / 12, PA MACMI / 1012, PA MACMT / 12, PA MACMI / MACMT / 12, PA MACMI / MACMT / MACM12, PA 6I / 6T / MACMI / MACMT / 12, PA 6I / 612 / MACMI / MACM12, PA 6T / 612 / MACMT / MACM12, PA 6I / 6T / 612 / MACMI / MACMT / MACM12,PA 6I / 6T / MACMI / MACMT / PACMI / PACMT / 12,PA MACMI / MACMT / MACM36, PA MACMI / MACM36, PA The selection is made from the group consisting of MACMT / MACM36, PA PACMI / 12, PA PACMT / 12, PA PACMT / 6, PA PACMI / 6, and mixtures thereof.

[0039] Particularly preferably, component A consists of the following combinations of polyamides A1 and A2. ● Polyamide A1 is PA6I / 6T / 612 / MACMI / MACMT / MACM12, and polyamide A2 is PA12, or ● Polyamide A1 is PA MACMI / 12, polyamide A2 is PA12, or ● Polyamide A1 is PA MACM12, and polyamide A2 is PA12.

[0040] Preferably, component A consists of polyamides A1 and A2 as follows. 50 to 95 wt% polyamide A1 and 5 to 50 wt% polyamide A2, or 60 to 85 wt% polyamide A1 and 15 to 40 wt% polyamide A2, or 65 to 80% by weight of polyamide A1 and 20 to 35% by weight of polyamide A2. In this case, the sum of components A1 and A2 is 100% by weight of component A.

[0041] According to a more preferred embodiment of the present invention, component A1 has a glass transition temperature of at least 135°C, preferably at least 140°C, particularly preferably 145°C, and particularly preferably 150°C, as determined according to DIN EN ISO 11357-2:2020.

[0042] According to a more preferred embodiment of the present invention, polyamide A1 does not contain monomers having aromatic structural units.

[0043] Preferably, component A1 has a relative viscosity in the range of 1.35 to 2.40, particularly preferably 1.40 to 1.90, and more preferably 1.45 to 1.80, measured according to ISO 307:2007, in a solution of 0.5 g of polymer in 100 ml of m-cresol at 20°C. Preferably, component A2 has a relative viscosity in the range of 1.70 to 3.00, particularly preferably 1.75 to 2.70, and more preferably 1.80 to 2.40, measured according to ISO 307:2007, in a solution of 0.5 g of polymer in 100 ml of m-cresol at 20°C.

[0044] Component B Component B is a colorant or mixture of colorants suitable for coloring polyamide molded compounds black. For the purposes of the present invention, the colored black is the color lightness L of the polyamide molded compound as measured according to DIN EN ISO 11664-4:2020. * This means that the maximum value is 32. Colorants can be organic or inorganic, dyes or pigments. Dyes are colorants that typically do not scatter light but absorb light of specific visible wavelengths. Dyes are often soluble in polymer matrices at certain concentrations.

[0045] Pigments are typically organic or inorganic dyes that exist as separate, insoluble particles in a polymer matrix. The designation of a particular dye as a pigment or dye depends on the polymer matrix, dye concentration and crystallinity, temperature, and other factors. With respect to the present invention, preferred colorants are soluble in the polyamide molding composition at the concentration required to color the molded article. The polyamide molding composition according to the present invention is free of carbon black and / or nigrosine, i.e., it contains neither carbon black nor nigrosine.

[0046] According to the present invention, the colorants are used in amounts and combinations sufficient to color the molded compound black and substantially opaque, and in particular in amounts and combinations sufficient to achieve the lightness values ​​(color lightness) and / or transmission values ​​in the visible and near-infrared ranges described below. The specific amount of colorant used depends, among other things, on its solubility and extinction coefficient in the thermoplastic matrix, as well as whether it is used in combination with one or more additional colorants.

[0047] The proportion of component B is in the range of 0.05 to 2.0% by weight, based on the sum of components A to D. According to a preferred embodiment of the present invention, the proportion of component B is in the range of 0.08 to 1.5% by weight, particularly preferably 0.10 to 1.0% by weight, based on the sum of components A to D in each case.

[0048] Suitable colorants generally exhibit high absorption coefficients in the visible wavelength range, low absorption coefficients in the near-infrared (NIR) range, and high thermal stability. High thermal stability of a colorant is indicated by the absence of significant color shift or thermal decomposition during the production and processing of colored molded compounds by injection molding or extrusion in the temperature range of 230 to 300°C. Furthermore, colorants should not attack or decompose the polymer, which could result in unacceptable loss of mechanical properties during molding or the formation of gaseous byproducts.

[0049] Synthetic colorants are typically derived from coal tar or petroleum intermediates. Many different types of colorants are available for use in thermoplastic materials. For example, the Color Index lists many different chemical classes of colorants. These include nitroso, nitro, monoazo, diazo, triazo, polyazo, azo, stilbene, carotenoids, diphenylmethane, triarylmethane, xanthenes, quinolines, acridine, methine, thiazole, indamine, indophenol, azine, oxazine, thiazine, sulfur, lactone, aminoketone, hydroxyketone, anthraquinone, indigoid and phthalocyanine, as well as inorganic pigments.

[0050] Preferred colorants or combinations of colorants are selected from the group consisting of pyrazolone, perinone and anthraquinone, methine, azo and coumarin dyes and / or metal-containing pigments, such as inorganic pigments and metal complexes of azo, azomethine or methine dyes, azomethine, quinacridone, dioxazine, isoindoline, isoindolinone, perylene, phthalocyanine, pyrrolopyrrole and thioindigo colorants.

[0051] Examples of inorganic pigments include antimony trioxide, antimony pentoxide, basic lead carbonate, basic lead sulfate or lead silicate, lithopone, titanium dioxide (anatase, rutile), zinc oxide, zinc sulfide, metal oxides such as Berlin / Prussian blue, lead chromate, lead sulfochromate, chromium antimonate, chromium oxide, iron oxide, cobalt blue, cobalt chromium blue, cobalt nickel gray, manganese blue, manganese violet, molybdate orange, molybdate red, nickel antimonate, ultramarine blue, and metal sulfides such as antimony trisulfide, cadmium sulfide, cadmium sulfoselenide, zirconium silicate, zirconium vanadium blue, and zirconium praseodymium yellow. Suitable polymer-soluble dyes include, for example, anthraquinone-based disperse dyes such as alkylamino-, amino-, arylamino-, cyclohexylamino-, hydroxy-, hydroxyamino-, or phenyl-mercaptoanthraquinone, as well as azo dyes, particularly monoazo dyes with 1:2-chromium or cobalt metal complexes, and fluorescent dyes such as benzothiazole, coumarin, oxaline, or thiazine-based dyes.

[0052] Preferably, at least one colorant B comprises at least one colorant described below, and particularly preferably, at least one colorant B is selected from the group of colorants described below, as shown below as Color Index Generic Names (CIGN). These include Solvent Green 3, Solvent Green 28, Solvent Red 52, Solvent Red 111, Solvent Red 135, Solvent Red 169, Solvent Red 179, Solvent Red 207, Disperse Red 22, Vat Red 41, Solvent Orange 60, Solvent Orange 63, Solvent Violet 13, Solvent Violet 14, Solvent Violet 50, Disperse Blue 73, Solvent Blue 97, Solvent Blue 101, Solvent Blue 104, Solvent Blue 138, Disperse Yellow 160, Solvent Yellow 84, Solvent Yellow 93, Solvent Yellow 98, Solvent Yellow 163, Solvent Yellow 160:1, and mixtures thereof. These colorants exhibit good thermal stability.

[0053] Preferred colorants having a phthalocyanine structure include, for example, Pigment Blue 15:1, Pigment 15:3, Pigment Blue 16, and Pigment Green 7.

[0054] Preferred components B are Solvent Brown 53, Pigment Brown 23, Pigment Brown 24, Pigment Brown 25, Pigment Orange 68, Solvent Orange 60, Solvent Orange 63, and Pigment Brown 6.

[0055] Particularly preferred dyes are Solvent Red 135, Solvent Red 179, Solvent Violet 13, Solvent Violet 14, Solvent Violet 36, Solvent Violet 50, Disperse Blue 73, Solvent Yellow 93, Solvent Green 3, Disperse Yellow 160, Solvent Blue 97, and mixtures containing at least one of the dyes mentioned above.

[0056] Preferably, the polyamide molding compound of the present invention has a color brightness L measured in the CIE-LAB light space. * The coloring agent (component B) is provided such that the ratio is 30 or less, and particularly preferably 27 or less.

[0057] In a more preferred embodiment, the colorants are selected and their content adjusted such that the transmittance of a 60 × 60 × 2 mm sheet manufactured from the polyamide molded compound according to the present invention in the wavelength range of 400 to 650 nm is up to 10%, preferably up to 5%, and particularly preferably up to 3%. Measurements were performed using an Agilent Technologies Cary 5000 UV / VIS / NIR spectrometer equipped with an integrating sphere in accordance with DIN EN ISO 13468-2:2006.

[0058] Furthermore, it is preferable that a sheet measuring 60 × 60 × 2 mm produced from the polyamide molded compound according to the present invention has a transmittance of at least 50%, particularly preferably at least 60%, and especially preferably at least 70% in the wavelength range of 750 to 1200 nm. Measurements were performed using an Agilent Technologies Cary 5000 UV / VIS / NIR spectrometer equipped with an integrating sphere in accordance with DIN EN ISO 13468-2:2006.

[0059] Particularly preferred is the coloring agent to be selected from the following group of coloring agent mixtures. ● Solvent Green 3 and Solvent Red 179 ● Solvent Red 52 and Solvent Blue 97 ● Solvent Green 3, Solvent Blue 97, and Solvent Red 179.

[0060] A particularly preferred coloring agent is mixture B, which consists of the following components. B1 20~40 wt% Solvent Green3 B2 10-30 wt% Solvent Blue 97 B3 40~70wt% Solvent Red 179 The sum of components B1 to B3 is 100% by weight of mixture B (component B). Preferably, the content of this colorant mixture B is 0.15 to 0.25% by weight based on the sum of components A to D.

[0061] Component C The molding composition according to the present invention contains, as component C, at least one stabilizer selected from the group consisting of inorganic and organic stabilizers, particularly antioxidants, ozone degradation inhibitors, heat stabilizers, light stabilizers, UV stabilizers, UV absorbers, or UV blockers. Preferably, stabilizer C is a UV stabilizer and / or a heat stabilizer.

[0062] The content of stabilizer C is, in all cases, 0.10 to 3.0% by weight, preferably 0.20 to 2.5% by weight, and particularly preferably 0.25 to 2.3% by weight, based on the sum of A to D.

[0063] According to a preferred embodiment, component C may be selected from the following group. ● Monovalent or divalent copper compounds, particularly salts of monovalent or divalent copper with inorganic or organic acids or monovalent or divalent phenols, oxides of monovalent or divalent copper, or complex compounds of copper salts with ammonia, amines, amides, lactams, cyanides or phosphines, preferably Cu(I) or Cu(II) salts of hydrohalic acids, copper salts of hydrocyanic acids or aliphatic carboxylic acids, monovalent copper compounds CuCl, CuBr, CuI, CuCN and Cu2O, and divalent copper compounds CuCl2, CuSO4, CuO, copper(II) acetate or copper(II) stearate are particularly preferred, or mixtures of these compounds are used as is or preferably in the form of concentrates. In this regard, concentrate means a polymer containing a high concentration of copper salt or copper compound, preferably having the same or essentially the same chemical properties as component A1 or A2. In particular, copper compounds are preferably used in combination with other metal halides, such as alkali halides, including Na, KI, NaBr, and KBr, with a molar ratio of metal halide to copper of 0.5 to 20, preferably 1 to 10, and particularly preferably 2 to 7. ● Stabilizers based on secondary aromatic amines ● Stabilizers based on stereohindered phenols ● Phosphites and phosphates, ● A stabilizer selected from the group consisting of N,N'-oxamide, hydroxyphenyltriazine, hydroxyphenylbenzotriazole, dibenzoylmethane, aminohydroxybenzoylbenzoate, hydroxybenzophenone, hindered amine light stabilizer (HALS), and mixtures of the above stabilizers.

[0064] Particularly preferred examples of secondary aromatic amine-based stabilizers that can be used in accordance with the present invention are adducts of phenylenediamine and acetone (Naugard A), adducts of phenylenediamine and linol, Naugard 445, N,N'-dinaphthyl-p-phenylenediamine, N-phenyl-N'-cyclohexyl-p-phenylenediamine, or mixtures of two or more thereof. Preferred examples of stereohindered phenol-based stabilizers that can be used in accordance with the present invention are N,N'-hexamethylene-bis-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionamide, bis-(3,3-bis-(4'-hydroxy-3'-tert-butylphenyl)-butanoic acid) glycol ester, 2,1'-thioethylbis-(3-(3,5-di.tert-butyl-4-hydroxyphenyl)-propionate, 4-4'-butylidene-bis-(3-methyl-6-tert.butylphenol), triethylene glycol 3-(3-tert-butyl-4-hydroxy-5-methylphenyl)-propionate, or mixtures of two or more of these stabilizers.

[0065] Preferred phosphates and phosphonites include triphenyl phosphite, diphenylalkyl phosphite, phenyl dialkyl phosphite, tris(nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, diisodecyloxy pentaerythritol diphosphite, and bis(2,4-di-tert-butyl-6-methylphenyl) pentaerythritol diphosphite. These include thritol diphosphite, bis(2,4,6-tris-(tert-butylphenyl))pentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylenediphosphonite, 6-isooctyloxy-2,4,8,10-tetra-tert-butyl-12H-dibenzo-[d,g]-1,3,2-dioxaphosphosine, 6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl-dibenzo-[d,g]-1,3,2-dioxaphosphosine, bis(2,4-di-tert-butyl-6-methylphenyl)methyl phosphite, and bis(2,4-di-tert-butyl-6-methylphenyl)ethyl phosphite. In particular, tris[2-tert-butyl-4-thio(2'-methyl-4'-hydroxy-5'-tert-butyl)-phenyl-5-methyl]phenyl phosphite and tris(2,4-di-tert-butylphenyl)phosphorous acid (Hostanox® PAR24:Clariant, a commercial product from Basel) phosphite are preferred.

[0066] A preferred embodiment of the thermal stabilizer is a combination of Irgatec NC 66 (available from BASF) and a copper stabilizer based on CuI and KI. In particular, thermal stabilization based solely on CuI and KI is preferred.

[0067] In a more preferred embodiment, the heat stabilizer of component C is selected from the group consisting of phenolic heat stabilizers, phosphite heat stabilizers, amine heat stabilizers, or mixtures or combinations thereof, and is particularly preferably imparted to component C selected from the group consisting of triethylene glycol bis(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate, pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid), N,N'-hexamethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionamide], tris(2,4-di-tert-butylphenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, or mixtures thereof.

[0068] Preferred organic stabilizers are phenol and / or phosphite compounds such as Irganox 245, Irganox 1010, Irganox 1098, Hostanox PAR24, or Irgafos 168. Particularly preferred as component (D) is a mixture of 10 parts by weight of a mixture of Irganox 1010 (CAS 6683-19-8, phenolic antioxidant) and Anox 20 (CAS 6683-19-8, phenolic antioxidant) in a ratio of 7:3, and 2 parts by weight of Hostanox PAR24 (CAS:31570-04-4, tris(2,4-di-tert-butylphenyl) phosphite).

[0069] Preferred UV stabilizers include, for example, N-(2-ethoxyphenyl)-N'-(2-ethylphenyl)oxamide (Tinuvin 312), 2-(4,6-diphenyl-1,3,5-triazine-2yl)-5-hexyloxyphenol (Tinuvin 1577), 2-(4,6-diaryl-1,3,5-triazine-2yl)-5-(alkoxy-substituted)-phenol (Tinuvin 1600), 2-tert-butyl-6-(5-chlorobenzotriazole-2-yl)-4-methylphenol (Tinuvin 326), 2-(benzo-triazole-2-yl)-4,6-bis(2-phenylpropane-2-yl)phenol (Tinuvin 234), and bis(2,2,6-tetramethyl-4-piperidyl) sebacate (Tinuvin 770). DF), 2-(2-hydroxyphenyl)-benzotriazole derivative (Tinuvin Carboprotect), 2-(benzotriazole-2-yl)-4,6-bis(2-methylbutan-2-yl)phenol (Tinuvin 328), 2-(benzotriazole-2-yl)-6-[[3-(benzotriazole-2-yl)-2-hydroxy-5-(2,4,4-trimethylpentan-2-yl)phenyl]methyl]-4-(2,4,4-trimethylpentan-2-yl)phenol (Tinuvin 360), poly[[6-[(1,1,3,3-tetramethylbutyl)amino]~1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethyl-4-piperidinyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidinyl)imino]](Chimasorb Selected from the group consisting of 944 FD), 1-(4-methoxyphenyl)-3-(4-tert-butylphenyl)propane-1,3-dione (Parsol 1789), and mixtures thereof.

[0070] Component D The polyamide molding composition according to the present invention further comprises 0 to 10% by weight of component D based on the total of components A to D.

[0071] According to a preferred embodiment of the present invention, the proportion of component D in the polyamide molding composition is in the range of 0 to 5.0% by weight, particularly preferably 0.10 to 2.0% by weight, based on the sum of components A to D in each case.

[0072] A more preferred embodiment is that at least one additive D is selected from the group consisting of monomers, particularly lactams, plasticizers, impact modifiers, lubricants, mold release agents, condensation catalysts, chain modifiers, particularly monofunctional carboxylic acids or amines, defoamers, antiblocking agents, natural layer silicates, synthetic layer silicates, nanoscale fillers, and mixtures thereof.

[0073] Polyamide molding composition A preferred embodiment of the present invention results in a polyamide molding composition in which the proportion of component A is in the range of 91 to 99.72 wt%, particularly preferably in the range of 94.7 to 99.55 wt%, the proportion of component B in the polyamide molding composition is in the range of 0.08 to 1.5 wt%, particularly preferably in the range of 0.10 to 1.0 wt%, the proportion of component C in the molding composition is in the range of 0.20 to 2.5 wt%, particularly preferably in the range of 0.25 to 2.3 wt%, and the proportion of component D in the molding composition is in the range of 0 to 5.0 wt%, particularly preferably in the range of 0.10 to 2.0 wt%, where the proportions referred to in each case are based on the sum of components A to D.

[0074] The polyamide molding composition according to the present invention does not contain carbon black and / or nigrosine; that is, it does not contain either carbon black or nigrosine.

[0075] The molded compound is colored black, meaning it has high absorption in the visible range and therefore low light transmittance. The color lightness L was measured in the CIELAB color space according to DIN EN ISO 11664-4:2020 on a plate measuring 60 × 60 × 2 mm. * The maximum number is 32, preferably 30, and most preferably 27.

[0076] Preferably, the transmittance in the wavelength range of 400 to 650 nm is at most 10%, particularly preferably at most 5%, and particularly preferably at most 3%. Furthermore, the transmittance in the wavelength range of 750 to 1200 nm is preferably at least 50%, particularly preferably at least 60%, and particularly preferably at least 70%, and the transmittance in the wavelength range of 400 to 650 nm is determined in each case, in accordance with DIN EN ISO 13468-2:2006, by a Brand Cary 5000 UV / VIS / NIR spectrometer manufactured by Agilent Technologies with an integrating sphere on a plate of dimensions 60 × 60 × 2 mm, at most 10%, particularly preferably at most 5%, and particularly preferably at most 3%.

[0077] According to another preferred embodiment of the present invention, a molded article (a sheet with dimensions of 60 × 60 × 2 mm) made of a polyamide molding compound in accordance with ISO 2813:2015 has a glossiness of 90% or more, preferably 95% or more, and particularly preferably 100% or more, measured at a temperature of 23°C and an angle of 60°.

[0078] In another preferred embodiment of the present invention, the tensile modulus of the polyamide molded composition, as measured according to ISO 527:2012, is in the range of 1400 to 3000 MPa, preferably 1500 to 2800 MPa, and more preferably 1600 to 2700 MPa.

[0079] According to another preferred embodiment of the present invention, the fracture stress of the polyamide molded composition, as measured according to ISO 527:2012, is 40 to 120 MPa, preferably 45 to 100 MPa, and particularly preferably 50 to 90 MPa.

[0080] According to another preferred embodiment of the present invention, the elongation at break of the polyamide molded composition, as measured according to ISO 527:2012, is greater than 20%, preferably greater than 40%, and particularly preferably in the range of 50 to 200%.

[0081] According to another preferred embodiment of the present invention, the impact strength of the polyamide molding composition measured according to ISO 179 / 2:1997 is greater than 30 kJ / mm 2 and preferably greater than 50 kJ / mm 2 and particularly preferably not broken.

[0082] According to a further preferred embodiment of the present invention, the notched impact strength of the polyamide molding composition determined according to ISO 179 / 2:1997 is at least 6 kJ / mm 2 and preferably at least 7 kJ / mm 2 and particularly preferably from 7 to 20 kJ / mm 2 is.

[0083] The preferred polyamide molding composition of the present invention consists of the following components. 85 to 99.85% by weight of component A, where component A consists of polyamide A1 or a mixture consisting of 60 to 90% by weight of polyamide A1 and 10 to 40% by weight of polyamide A2, A1 is at least one amorphous or microcrystalline polyamide containing more than 60 mol% of monomers having only aliphatic structural units based on the total amount of monomers, A2 is at least one acyclic aliphatic polyamide, where the total of components A1 and A2 is 100% by weight of component A, 0.05 to 2.0% by weight of at least one colorant B, 0.10 to 3.0% by weight of at least one stabilizer C, 0 to 10% by weight of at least one additive D different from A, B and C, and the weight percentages of components A to D are added up to 100 wt%, The polyamide molding composition does not contain carbon black or nigrosine, a color lightness L of at most 30, measured according to DIN EN ISO 11664-4:2020 in the CIELAB color space *Polyamide A1 having at least 90% clarity and a maximum of 3% haze, as measured according to ASTM D 1003-21. The lightness and clarity of the color are determined in a plate with dimensions of 60 × 60 × 2 mm.

[0084] Another preferred polyamide molding composition of the present invention consists of the following components. Component A in an amount of 85 to 99.85% by weight, in which case component A consists of polyamide A1 or a mixture of polyamide A1 and polyamide A2 consisting of 60 to 90% by weight of polyamide A1 and 10 to 40% by weight of polyamide A2. A1 is an amorphous or microcrystalline polyamide containing more than 60 mol% of monomers having only aliphatic structural units, based on the total amount of monomers. A2 is at least one acyclic aliphatic polyamide, Polyamide A1 is selected as 6I / 6T / 612 / MACMI / MACMT / MACM12, MACM12, MACMI / 12, PACMI / 12, PACM12, MACM12 / PACM12, and mixtures thereof. Polyamide A2 is selected from the group consisting of PA11, PA12, PA1010, PA1016, PA610, PA612, PA614, PA616, PA66, PA6, PA6 / 12, and mixtures thereof, and the mixtures thereof are preferably selected as PA6 / 12 or PA12, and the sum of components A1 and A2 is 100% by weight of component A. At least one colorant B in an amount of 0.05 to 2.0% by weight, consisting of the following: B1 20-40% by weight Solvent Green 3 B2 10-30% by weight Solvent Blue 97 B3 40~70wt%Solvent Red 179 In this case, the sum of components B1 to B3 is 100% by weight of component B. 0.10 to 3.0% by weight of at least one stabilizer C, At least one additive D, distinct from A, B, and C, in a quantity of 0 to 10% by weight, with the total weight percentage of components A to D being 100% by weight, the polyamide molded composition contains neither carbon black nor nigrosine. Color lightness L measured in the CIELAB color space according to DIN EN ISO 11664-4:2020. * The maximum value is 30, and polyamide A1 is measured according to ASTM D 1003-21, having at least 90% clarity and a maximum of 3% haze. Color brightness and clarity are determined on a 60 × 60 × 2 mm sheet.

[0085] Molded parts The present invention further relates to molded parts or articles comprising the molding composition defined above, preferably the article being made of this polyamide molding composition. In particular, these molded articles are selected from the group consisting of interior and exterior parts for automobiles, motorcycles, campervans or caravans, building and facade parts, decorative structural frames, operating knobs or levers, covers, visible surfaces, backlit parts, mobile phone screens, tablets, electronic device housings, vehicle decorative parts, home appliances, containers, vehicle keys, leisure and outdoor goods.

[0086] use Furthermore, the present invention relates to the use of a colorant or colorant mixture that does not contain carbon black or nigrosine, having high absorption in the wavelength range between 400 and 650 nm and low absorption in the wavelength range between 750 and 1200 nm, and having a color lightness L of 32 or less as determined according to DIN EN ISO 11664-4:2020 in the CIELAB color space on a plate of dimensions 60 × 60 × 2 mm. * This invention relates to the use of a transparent polyamide containing more than 60 mol% monomers having aliphatic structural units, based on the total amount of monomers having aliphatic structural units, for improving the weather resistance of polyamide molding compounds.

[0087] The following examples are used to illustrate the subject matter of the present invention in more detail, without limiting them to the specific embodiments shown herein. In the context of this application, the following measurement methods were used.

[0088] Hayes, Transparency Transparency and haze were measured at 23°C using a CIE emitter C on a 2mm thick sheet (60mm x 60mm surface area) with a BYK Gardner Haze-gard Plus meter according to ASTM D 1003-21.

[0089] Melting point (Tm) and enthalpy of melting (ΔHm).

[0090] The melting point and enthalpy of melting were measured on granules according to DIN EN ISO 11357-3:2018. Differential scanning calorimetry (DSC) measurements were performed at a heating rate of 20 K / min.

[0091] Glass transition temperature, Tg The glass transition temperature (Tg) was determined for granules using differential scanning calorimetry (DSC) according to DIN EN ISO 11357-2:2020. This was performed at a heating rate of 20 K / min for each heating step. After the first heating, the sample was quenched in dry ice. The Tg was determined during the second heating. The midpoint of the glass transition region was defined as Tg and determined by the "half-height" method.

[0092] Relative viscosity η rel Relative viscosity was measured at 20°C according to ISO 307 (2007). For this purpose, 0.5 g of polymer granules was weighed into 100 ml of m-cresol, and the relative viscosity (RV) was calculated according to RV = t / t0 as per Section 11 of the standard.

[0093] Tensile E modulus Tensile Young's modulus and tensile strength were determined according to ISO 527 (2012) using an ISO tensile bar (Type A1, mass 170 × 20 / 10 × 4) manufactured according to standard ISO / CD 3167 (2003), at a tensile speed of 1 mm / min and 23°C.

[0094] Stress at fracture and elongation at fracture Tensile fracture stress and tensile fracture elongation were measured according to ISO 527 (2012) using an ISO tensile bar, type A1 (mass 170 × 20 / 10 × 4 mm), manufactured according to ISO / CD 3167 (2003) standard, at 23°C and a tensile speed of 50 mm / min.

[0095] Charpy impact strength Charpy impact strength was measured using an ISO test bar, type B1 (mass 80 × 10 × 4 mm), manufactured according to standard ISO / CD 3167 (2003), and ISO 179 / 2 * eU (1997, * The procedure was carried out at 23°C according to the instrumentation instructions.

[0096] Charpy-notch impact strength Charpy impact strength was measured using an ISO test bar, type B1 (mass 80 × 10 × 4 mm), manufactured according to ISO / CD 3167 (2003), at 23°C under ISO 179 / 2 * eA (1997, * The determination was made according to (2 = instrumentation).

[0097] Gloss 60° In accordance with ISO 2813 (2015), gloss was measured on a 60 × 60 × 2 mm plate at a 60° angle and 23°C using a Minolta Multi Gloss 268 instrument. The gloss value is given in dimensionless gloss units (GU). Dry test specimens were injection molded at room temperature and then stored in a dry environment, i.e., on silica gel, for 48 hours.

[0098] Color measurement CIE L Reference and Test Color Plates * a * b* The value was determined in front of a white-coated contrast plate according to DIN EN ISO 11664-4:2020, using a Datacolor spectrophotometer (instrument name: Datacolor 650) under the following measurement conditions.

[0099] Measurement mode: Reflection, Measurement geometry: D / 8°, Light source: D 65 10, Gloss: Single closed, Calibration: UV calibration, Measurement aperture: SAV. Reference and sample L by CIELAB system * a * , and b * Using the value of , the color brightness difference ΔL * It is calculated as follows: JPEG2023014027000001.jpg20170

[0100] Color position (L * a * b * ) Reference and (L * a * b * The color distance ΔE between the sample and the target is calculated as the Euclidean distance as follows: JPEG2023014027000002.jpg24170

[0101] Color plates with dimensions of 2 x 40 x 50 mm used for color measurement were injected from different materials using a tempered die in an Arburg all-electric injection molding machine (ARBURG Allrounder 320 A500-170). In the weather resistance test, ΔL * Alternatively, the reference for ΔE is an unadjusted or unweathered sample.

[0102] weather resistance Weather resistance was performed according to ISO 4892-2:2013 (artificial weathering with xenon lamps, "Florida climate") using a Weather-Ometer® Ci 4000 following procedure A. The radiation measured at 340 nm was 0.5 W / m². 2The following cycle was performed: 102 minutes of drying, 18 minutes of simulated rain, maintaining relative humidity at 65% during the "drying" phase. The black standard temperature (black panel) was 65°C ± 3°C.

[0103] Table 1 summarizes the materials used in the examples and comparisons.

[0104] JPEG2023014027000003.jpg245170

[0105] Generally, the components are mixed (formulated) in a polymer molten state in conventional compounding equipment such as a single-screw or twin-screw extruder or screw kneader to produce polyamide molded compounds. The components are supplied to feeders individually or in the form of a dry blend or masterbatch. In the case of dry blend production, dry polymer granules and additives are mixed. To avoid moisture absorption, mixing can be carried out under a dry, inert gas. The dosage of all components is adjusted by an electronically controlled scale to obtain the desired proportions of polymer and other components.

[0106] The compounding is carried out at a set extruder barrel temperature, for example, 230 to 350°C, preferably 240 to 300°C. Vacuuming can be applied upstream of the die, or degassing with air can be used. The molten material is discharged into a water tank in strand form and then pelletized, or it can be directly converted into pellet form by thermal knockdown in water. Preferably, water pelletizing or strand pelletizing is used for granulation.

[0107] The polyamide molded compound thus obtained, preferably in granular form, is then dried and subsequently processed into a molded product by injection molding. This is done by remelting the dried granules in a heatable cylinder and transporting the molten material into an injection mold in which the molten material can solidify.

[0108] Preparation of polyamide molded compounds according to Examples B1 to B3 and VB1 to VB3.

[0109] The compounds of Examples B1-B3 and Comparative Examples VB1-VB3 were produced using a Werner & Pfleiderer twin-screw extruder, Type ZSK 25. Polyamides A1 and A2, along with colorants and stabilizers, were mixed with lubricants in the proportions shown in Table 2 to form a dry blend. This dry blend was then weighed and fed into the extruder's feeder.

[0110] The temperature of the first barrel (feed) was set to 80°C, and the temperatures of the remaining barrels were set sequentially from 240°C to 280°C. Degassing was performed in the third zone upstream of the die using a nitrogen flow at a speed of 200 rpm and a throughput of 15 kg / hour. The polyamide molded compound released as strands was cooled in an 80°C water bath, granulated, and the resulting granules were dried at 90°C in a vacuum of 30 mbar until the water content was less than 0.1 wt%.

[0111] Preparation of test specimens As test specimens whose characteristics shown in Table 2 were determined, tensile rods, impact rods, and plates were injected from the obtained granules. The test specimens were manufactured using an Arburg injection molding machine, model Allrounder 420 C 1000-250. A cylinder temperature increase from 240°C to 280°C was used.

[0112] For the plates (2 mm × 60 mm × 60 mm) of Examples B3 and VB2, the mold temperature was 80°C, while all other plates were manufactured at a mold temperature of 120°C. For the tensile and impact rods, the die temperature was 80°C in each case. Unless otherwise specified, test specimens were used in a dry state. For this purpose, they were stored at room temperature for at least 48 hours after injection molding in a dry environment, i.e., on silica gel. For the plates (2 mm × 60 mm × 60 mm) used to determine optical properties, the surface of the injection molding die cavity was highly polished according to DIN EN ISO 4287:2010 so that the molded body (plate) had a high-gloss surface with a central arithmetic roughness Ra of 0.01 to 0.08 μm and / or a roughness depth Rz of 0.05 to 1.0 μm.

[0113] result

[0114] JPEG2023014027000004.jpg181170

[0115] Table 2 shows that the black polyamide compounds from Examples B1 to B3 have excellent gloss and sufficient dark coloration. Comparative Examples VB1 and VB2, further colored with carbon black, even show slightly higher brightness. In contrast to the comparative examples, the gloss of Examples B1 to B3 according to the present invention is largely retained after weathering. In the case of VB1 to VB3, the gloss decreases by 31 to 85% after 1000 hours in weathering tests compared to the initial value. The comparison between Examples B1 and B2 and Comparative Example VB3 clearly shows that if the concentration of aromatic structural units in the transparent polyamide VB3 is too high, the weathering stability decreases.

Claims

1. The following components: 85 to 99.85% by weight of component A, which consists of polyamide A1 or a mixture of polyamide A1 and A2, A1 is at least one amorphous or microcrystalline polyamide containing more than 60 mol% of monomers having only aliphatic structural units based on the total amount of monomers, A2 is at least one acyclic aliphatic polyamide, Component A, where the total of components A1 and A2 is 100% by weight of component A, 0.05 to 2.0% by weight of at least one colorant B, 0.10 to 3.0% by weight of at least one stabilizer C, Additive D, 0 to 10% by weight, other than A, B, and C, A polyamide molding composition comprising or preferably consisting of these components, The weight ratios of components A to D add up to 100% by weight, and the polyamide molding composition does not contain carbon black or nigrosine, The color lightness L determined in accordance with DIN EN ISO 11664-4:2020 in the CIELAB color space of a plate with dimensions 60×60×2 mm ＊ is at most 32, The polyamide A1 has a transparency of at least 88% and a haze of at most 5% when determined in each case according to ASTM-D1003-21 with a plate of dimensions 60×60×2 mm, polyamide molding composition.

2. The transmittance in the wavelength range of 750 to 1200 nm is at least 50%, preferably at least 60%, particularly preferably at least 70%, and the transmittance in the wavelength range of 400 to 650 nm is at most 10%, at most 5%, particularly preferably at most 3%, and in each case, it is determined using a UV / VIS / NIR spectrometer according to DIN EN ISO 13468-2:2006 with a plate of dimensions 60×60×2 mm. The polyamide molding composition according to Claim 1, characterized in that.

3. The at least one polyamide A1 is the following monomers: a-A1 15 to 100 mol% of alicyclic diamine based on the total amount of diamines of the total amount, b-A1 0 to 85 mol% of open-chain aliphatic diamine based on the total amount of diamines, c-A1 20 to 100 mol% of aliphatic dicarboxylic acid based on the total amount of dicarboxylic acids, d-A1 0 to 80 mol% of aromatic dicarboxylic acid based on the total amount of dicarboxylic acids, e-A1 0 to 40 mol% of aliphatic lactam and / or aliphatic aminocarboxylic acid having 6 to 12 carbon atoms based on the total amount of monomers a-A1 to e-A1, and is composed of, The total of diamines a-A1 and b-A1 is 100 mol%, and the total of dicarboxylic acids c-A1 and d-A1 is 100 mol% The polyamide molding composition according to claim 1 or 2, characterized in that it is so.

4. Based on the total amount of monomers, the at least one polyamide A1 contains monomers having only aliphatic structural units in the range of at least 63 mol%, preferably at least 68 mol%, particularly at least 70 mol%, particularly preferably 60 to 100 mol% or 63 to 100 mol% or 68 to 100 mol%. The polyamide molding composition according to claim 1 or 2, characterized in that it is so.

5. The polyamide molding composition according to claim 1 or 2, wherein the at least one polyamide A2 is selected from the group consisting of PA11, PA12, PA1010, PA1016, PA610, PA612, PA614, PA616, PA66, PA6, PA6 / 12, and mixtures thereof.

6. The components are 50 to 95% by weight of polyamide A1 and 5 to 50% by weight of polyamide A2, or 60 to 85% by weight of polyamide A1 and 15 to 40% by weight of polyamide A2, or 65 to 80% by weight of polyamide A1 and 20 to 35% by weight of polyamide A2 and The total of components A1 and A2 is 100% by weight of component A. The polyamide molding composition according to claim 1 or 2, characterized in that it is so.

7. The alicyclic diamine a-A1 is selected from the group consisting of bis-(4-amino-3-methylcyclohexyl)methane, bis-(4-aminocyclohexyl)methane, bis-(4-amino-3,5-dimethylcyclohexyl)methane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, and mixtures thereof, and / or The diamine b-A1 is selected from the group consisting of hexanediamine, particularly 1,6-hexanediamine, 1,9-nonanediamine, 2-methyl-1,8-octanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,13-tridecanediamine, 1,14-tetradecanediamine, 1,18-octadecanediamine, and mixtures thereof, and / or The aliphatic dicarboxylic acid c-A1 is selected from the group consisting of 1,6-hexanedioic acid, 1,9-nonanedioic acid, 1,10-decanedioic acid, 1,11-undecanedioic acid, 1,12-dodecanedioic acid, 1,13-tridecanedioic acid, 1,14-tetradecanedioic acid, 1,16-hexadecanedioic acid, 1,18-octadecanedioic acid, and mixtures thereof, and / or the aromatic dicarboxylic acid d-A1 is selected from the group consisting of terephthalic acid, isophthalic acid, 1,5-naphthalenedicarboxylic acid, and 2,6-naphthalenedicarboxylic acid, and mixtures thereof, and / or the lactam and / or the α,ω-aminocarboxylic acid e-A1 is selected from the group consisting of caprolactam (CL), α,ω-aminocaproic acid, α,ω-aminoundecanoic acid (AUA), laurolactam (LL), and α,ω-aminododecanoic acid (ADA), and mixtures thereof The polyamide molding composition according to claim 1 or 2, characterized in that.

8. The polyamide A1 is selected from the group consisting of PA MACM9, PA MACM10, PA MACM11, PA MACM12, PA MACM13, PA MACM14, PA MACM15, PA MACM16, PA MACM17, PA MACM18, PA MACM36, PA PACM9, PA PACM10, PA PACM11, PA PACM12, PA PACM13, PA PACM14, PA PACM15, PA PACM16, PA PACM17, PA PACM18, PA PACM36, PA TMDCC9, PA TMDCC10, PA TMDCC11, PA TMDCC12, PA TMDCC13, PA TMDCC14, PA TMDCC15, PA TMDCC16, PA TMDCC17, PA TMDCC18, PA TMDCC36, PA MACM10 / 1010, PA MACM10 / PACM10, PA MACM12 / 1012, PA MACM14 / 1014, PA PACM10 / 1010, PA PACM12 / 1012, PA PACM14 / 1014, PA MACM12 / PACM12, PA MACM14 / PACM14, PA MACMI / 12, PA MACMI / 1012, PA MACMT / 12, PA MACMI / MACMT / 12, PA MACMI / MACMT / MACM12, PA 6I / 6T / MACMI / MACMT / 12, PA 6I / 612 / MACMI / MACM12, PA 6T / 612 / MACMT / MACM12, PA 6I / 6T / 612 / MACMI / MACMT / MACM12, PA 6I / 6T / MACMI / MACMT / PACM1 / PACM12, PA MACMI / MACMT / MACM36, PA MACMI / MACM36, PAMACMT / MACM36, PA PACMI / 12, PA PACMT / 12, PA PACMT / 6, PA PACMI / 6, and blends thereof, the polyamide molding composition according to claim 1 or 2.

9. The coloring agent B is selected from the group consisting of pyrazolone, perinone and anthraquinone, methine, azo and coumarin dyes and / or metal-containing pigments, such as inorganic pigments and metal complexes of azo, azomethine or methine dyes, azomethine, quinacridone, dioxazine, isoindoline, isoindolinone, perylene, phthalocyanine, pyrrolopyrrole and thioindigo coloring agents, the polyamide molding composition according to claim 1 or 2.

10. The at least one coloring agent B is at least one of the coloring agents mentioned below: Solvent Green 3, Solvent Green 28, Solvent Red 52, Solvent Red 111, Solvent Red 135, Solvent Red 169, Solvent Red 179, Solvent Red 207, Disperse Red 22, Vat Red 41, Solvent Orange 60, Solvent Orange 63, Solvent Violet 13, Solvent Violet 14, Solvent Violet 50, Disperse Blue 73, Solvent Blue 97, Solvent Blue 101, Solvent Blue 104, Solvent Blue 138, Disperse Yellow 160, Solvent Yellow 84, Solvent Yellow 93, Solvent Yellow 98, Solvent Yellow 163, Solvent Yellow 160:1, and mixtures thereof The polyamide molding composition according to claim 1 or 2, characterized in that it preferably contains at least one of or consists of a group selected from these.

11. The at least one coloring agent B is as a dye mixture of Solvent Green 3 and Solvent Red 179, or Solvent Red 52 and Solvent Blue 97, or Solvent Green 3, Solvent Blue 97, and Solvent Red 179, or Component B1 20 to 40% by weight of Solvent Green 3, Component B2 10 to 30% by weight of Solvent Blue 97, Component B3, 40 to 70% by weight of Solvent Red 179 The polyamide molding composition according to claim 1 or 2, characterized in that it is selected as the dye mixture B consisting of, and the total of B1 to B3 is 100% by weight of the colorant B.

12. The polyamide molding composition according to claim 1 or 2, characterized in that the at least one stabilizer C is selected from the group consisting of inorganic and organic stabilizers, in particular antioxidants, anti-ozone degradation agents, heat stabilizers, light stabilizers, UV stabilizers, UV absorbers, or UV blockers.

13. The polyamide molding composition according to claim 1 or 2, characterized in that the at least one additive D is selected from the group consisting of plasticizers, impact resistance improvers, lubricants, mold release agents, condensation catalysts, chain regulators, in particular monofunctional carboxylic acids or amines, defoamers, anti-blocking agents, natural layered silicates, synthetic layered silicates, nanoscale fillers and mixtures thereof.

14. In particular, a molded article comprising, or preferably consisting of, the polyamide molding composition according to claim 1 or 2, selected from the group consisting of interior and exterior parts of automobiles, motorcycles, camper vans or caravans, building and facade parts, decorative structural frames, operating knobs or levers, covers, visible surfaces, parts with backlights, screens of mobile phones, tablets, housings of electronic devices, decorative parts of vehicles, household appliances, containers, vehicle keys, leisure and outdoor articles.

15. The color lightness L of 32 or less determined in accordance with DIN EN ISO 11664-4:2020 in the CIELAB color space on a plate with dimensions 60×60×2 mm ＊ Based on the total amount of monomers having, and for improving the weather resistance of a polyamide molding compound based on a transparent polyamide containing more than 60 mol% of monomers having an aliphatic structural unit, the use of a colorant having high absorption in the wavelength range between 400 and 650 nm and low absorption in the wavelength range between 750 and 1200 nm, and containing neither carbon black nor nigrosine.