Stain-resistant article and use thereof

Patent metadata

Field	Value
Publication number	US-9546272-B2
Application number	US-201314136861-A
Country	US
Kind code	B2
Filing date	Dec 20, 2013
Priority date	Dec 21, 2012
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

A polyamide molding composition for the production of a stain-resistant article, the staining tendency (ST) of the article being at least 2. The composition contains 30-100% by weight of a polyamide or a polyamide mixture, consisting of 50-100% by weight of at least one amorphous and/or microcrystalline polyamide having a glass transition temperature of at least 100° C., based on: 20-100 mol % of at least one cycloaliphatic diamine; and 0-80 mol % of at least one other aliphatic and/or aromatic diamine; and also aromatic and/or aliphatic dicarboxylic acids comprising at least 6 carbon atoms, and 0-50% by weight of at least one semi-aromatic polyamide. In addition, the molding composition comprises any of inorganic white pigments, fillers, impact toughness modifier and/or flame retardants.

First claim

The invention claimed is:

1. A method for the production of a stain-resistant article, a staining tendency (ST) of the article being 1 or 2, wherein the method includes the following steps:
preparing a polyamide moulding composition consisting of:
(A) 30-99.5% by weight of a polyamide or a polyamide mixture, consisting of:
(A1) 50-100% by weight of at least one amorphous and/or microcrystalline polyamide having a glass transition temperature of at least 100° C., measured according to ISO-norm 11357-11-2,
wherein amorphous polyamides of the polyamide (A1) have heats of fusion of at most 4 J/g, and
microcrystalline polyamides of the polyamide (A1) have heats of fusion in the range of 4-25 J/g,
in each case determined according to ISO 11357-11-2 on granulate, differential scanning calorimetry (DSC) with a heating rate of 20° C./min, based on:
(a1) 20-100 mol % of at least one cycloaliphatic diamine; and 0-80 mol % of at least one other aliphatic and/or aromatic diamine,
wherein the mol % within component (a1) complement to 100 mol %; and

(a2) aromatic and/or aliphatic dicarboxylic acids comprising at least 6 carbon atoms,
with the proviso that up to 45 mol % of the totality of monomers of components (a1) and (a2) can be replaced by lactams comprising 6 to 12 carbon atoms or amino carboxylic acids comprising 6 to 12 carbon atoms,

(A2) 0-50% by weight of at least one semi-aromatic polyamide different from (A1);
wherein both (A1) and (A2) are present in the composition and together form 100% of component (A);

(X) 0.5-10% by weight of one or several inorganic white pigments having an average particle size (D50) in the range of 0.1-40 μm, selected from the group consisting of barium sulphate, zinc oxide, zink sulphide, lithopone and titanium dioxide, in the rutile or anatase modification, titanium-zinc mixed oxides, and mixtures thereof;
(B) 0-70% by weight of fibrous fillers (B1) and/or particulate fillers (B2) with the exception of inorganic white pigments;
(C) 0-30% by weight of polymers different from (A);
(D) 0-25% by weight of a flame retardant; and
(E) 0-3% by weight of additives,
wherein the sum of the constituents (A)-(E) including (X) makes up 100% by weight
and;
injection moulding or extruding said polyamide moulding composition to form at least part of said stain-resistant article,
wherein the staining tendency (ST) is determined by a colour impression ΔE and is classified as follows:
ST=1: 0≦ΔE≦2
ST=2: 2<ΔE≦6
ST=3: 6<ΔE≦12
ST=4: ΔE>12,

the colour impression ΔE is calculated in accordance with ISO 12647 and ISO 13655 as follows:

Δ
⁢

⁢
E

=

(

L
sample
*

-

L
reference
*

)

2

+

(

a
sample
*

-

a
reference
*

)

2

+

(

b
sample
*

-

b
reference
*

)

2

.

2. The method according to claim 1 , wherein the polyamide of component (A1) has a glass transition temperature of at least 130° C. and/or wherein amorphous polyamides of the polyamide (A1) have a heat of fusion of at most 2 J/g, determined in accordance with ISO 11357-11-2 on the granulate, with use of differential scanning calorimetry (DSC) with a heating rate of 20° C./min,
and/or wherein microcrystalline polyamides of component (A1) have a heat of fusion in the range of 8-22 J/g, determined in accordance with ISO 11357-11-2 on the granulate, differential scanning calorimetry (DSC) with a heating rate of 20° C./min.

3. The method according to claim 1 , wherein the E value (colour location) determined in the CIELAB colour space in accordance with EN ISO 11664-4 is changed by a staining test by a AE value of at most 6, and/or wherein the articles have a luminance L* of >80, both before and after the staining.

4. The method according to claim 1 , wherein the proportion of (a1) within the component (A1) is formed from 40-100 mol % of at least one cycloaliphatic diamine; and 0-60 mol % of at least one other aliphatic and/or aromatic diamine.

5. The method according to claim 1 , wherein the component (A1) is free from terephthalic acid and/or isophthalic acid,
or wherein, if component (A1) contains terephthalic acid and/or isophthalic acid within the scope of (a2), or if (a2) is formed substantially by terephthalic acid and/or isophthalic acid, 10-40 mol % of the totality of monomers in components (a1) and (a2) are replaced by lactams comprising 6 to 12 carbon atoms or amino carboxylic acids comprising 6 to 12 carbon atoms.

6. The method according to claim 1 , wherein the proportion of terephthalic acid within component (A1) is at most 50 mol %, based on the sum of all dicarboxylic acids of component (A1).

7. The method according to claim 1 , wherein the component (A2) is formed from aromatic dicarboxylic acids selected from the group consisting of terephthalic acid, naphthalene dicarboxylic acid and isophthalic acid, and mixtures thereof, and/or from dicarboxylic acids selected from the group consisting of adipic acid, suberic acid, azelaic acid, sebacic acid, undecane diacid, dodecane diacid, tridecane diacid, tetradecane diacid, pentadecane diacid, hexadecane diacid, heptadecane diacid, octadecane diacid, C36-dimer fatty acid, cis- and/or trans-cyclohexane-1,4-dicarboxylic acid and/or cis- and/or trans-cyclohexane-1,3-dicarboxylic acid (CHDA) and mixtures thereof, and is also formed from diamines selected from the group consisting of 1,4-butanediamine, 1,5-pentanediamine, 2-methyl-1,5-pentanediamine, 2-butyl-2-ethyl-1,5-pentanediamine, 1,6-hexanediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 1,8-octanediamine, 2-methyl-1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,13-tridecanediamine, 1,14-tetradecanediamine, m-xylylenediamine and p-xylylenediamine, wherein the polyamides (A2) contain

Assignees

• Ems Patent Ag

Inventors

• Aepli Etienne
• Pfleghar Mark
• Hoffmann Botho
• Hoff Heinz

Classifications

• C08K3/30 Primary

  Sulfur-, selenium- or tellurium-containing compounds · CPC title

• C08L77/06 Primary

  Polyamides derived from polyamines and polycarboxylic acids (C08L77/10 takes precedence) · CPC title

• C08K2003/2241

  Titanium dioxide · CPC title

• C08K2003/3036

  of zinc · CPC title

• C08L2205/02

  containing two or more polymers of the same C08L -group · CPC title