Multilayer body, comprising a substrate layer containing polycarbonate, talc and wax

Patent metadata

Field	Value
Publication number	US-12012494-B2
Application number	US-201816956532-A
Country	US
Kind code	B2
Filing date	Dec 12, 2018
Priority date	Dec 19, 2017
Publication date	Jun 18, 2024
Grant date	Jun 18, 2024

Abstract

The invention relates to a multilayer body comprising at least one substrate layer, a metal layer bonded directly thereto and optionally at least one protective layer atop the metal layer, wherein the substrate layer comprises a composition which is obtained by mixing polycarbonate, talc and a specific wax. It was shown that the multilayer bodies obtained are particularly suitable for use as reflectors and (housing) components for light sources and heat sources and displays.

First claim

The invention claimed is:

1. A multilayer body comprising
I) a substrate layer (S),
II) a metal layer (M) bonded directly to the substrate layer and
III) optionally a protective layer (P) atop the metal layer, wherein the substrate layer comprises a composition obtained by mixing components A)-C) and optionally component D), wherein
A) is a polycarbonate,
B) is an unsized talc having a median particle diameter D50 of 0.01 to 9.5 μm, where the particle diameter D50 is determined by sedimentation analysis,
C) is at least one anhydride-modified alpha-olefin polymer having an acid number of at least 30 mg KOH/g, determined by means of potentiometric titration with alcoholic potassium hydroxide solution according to DIN ISO 17025:2005, and an average molecular weight MW of 4000 to 40 000 g/mol, where the average molecular weight MW is determined by means of gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration,
and optionally
D) a portion of the amount of component B) may be replaced by at least one filler different from the unsized talc selected from the group consisting of an expanded graphite having a particle diameter D50 of less than 800 μm or a mixture of the aforementioned expanded graphite with unexpanded graphite and a boron nitride, where, in the case of graphite, up to 8 parts by weight of the amount of component B) may be replaced and where, in the case of boron nitride, up to 15 parts by weight of the amount of component B) may be replaced,
wherein the amounts of components B) and C) prior to mixing with component C) are matched to one another such that, for every 10 parts by weight of component B), 0.10 to 1.4 parts by weight of component C) are used, and wherein the composition is free of graft polymers and polyesters.

2. The multilayer body according to claim 1 , wherein the amount of B) is 12% to 45% by weight, based on the overall composition.

3. The multilayer body according to claim 1 , wherein the amount of B) is 18% to 35% by weight, based on the overall composition.

4. The multilayer body according to claim 1 , wherein the amounts of B) and C) prior to mixing are matched to one another such that, for every 10 parts by weight of component B), 0.25 to 1.4 parts by weight of component C) are used.

5. The multilayer body according to claim 1 , wherein the talc or talc mixture of component B) has a pH of 8 to 10, wherein the pH of the talc or talc mixture is determined according to EN ISO 787-9:1995.

6. The multilayer body according to claim 1 , wherein component B) has a median particle diameter D50 of 0.5 to 3.0 μm, wherein the particle diameter D50 is determined by sedimentation analysis.

7. The multilayer body according to claim 1 , wherein component B) has a BET surface area of 7.5 to 20.0 m 2 /g.

8. The multilayer body according to claim 1 , wherein the substrate layer has a thickness of 0.1 mm to 6.0 mm, the metal layer a thickness of 10 nm to 1000 nm, and the optional protective layer a thickness of 5 nm to 200 nm.

9. The multilayer body according to claim 1 , wherein the metal layer comprises at least one metal which is selected from the group consisting of aluminium, silver, chromium, titanium and palladium.

10. The multilayer body according to claim 1 , wherein the metal layer comprises silver or aluminium.

11. The multilayer body according to claim 1 , wherein, if graphite is present as component D), 2 to 7 parts by weight of the amount of component B) are replaced, and wherein, if boron nitride is present as component D), 2 to 12 parts by weight of the amount of component B) are replaced.

12. An article comprising the multilayer body according to claim 1 , wherein the article is selected from the group consisting of reflectors, components of light sources, and components of heat sources.

13. A process for producing the multilayer body according to claim 1 , comprising the steps of
a) forming the substrate layer by injection moulding or extrusion of the composition, at least comprising components A) to C), optionally comprising component D),
b) applying the metal layer to the layer obtained in step (a) in a plasma process and
c) optionally applying at least one further layer, and
d) optionally applying the protective layer to the layer obtained in step (b) or (c).

14. A method comprising providing at least one anhydride-modified alpha-olefin polymer C) having an acid number of at least 30 mg KOH/g and an average molecular weight Mw of 4000 to 25 000 g/mol, wherein the average molecular weight M W is determined by means of gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration, for production of a substrate layer of a multilayer body,
wherein the multilayer body comprises at least the one substrate layer, a metal layer bonded directly to the substrate layer and optionally at least one layer atop the metal layer, and
wherein the substrate layer comprises a composition which is obtained by mixing at least components A)-C) and optionally component D), wherein
A) is a polycarbonate and
B) is an unsized talc,
and optionally
D) a portion of the amount of component B) may be replaced by at least one filler different from the unsized talc selected from the group consisting of an expanded graphite having a particle diameter D50 of less than 800 μm or a mixture of the aforementioned expanded graphite with unexpanded graphite and a boron nitride.

15. The method according to claim 14 , wherein the amounts of B) and C) prior to mixing are matched to one another such that, for every 10 parts by weight of component B), 0.25 to 1.4 parts by weight of component C) are used.

Assignees

• Covestro Deutschland Ag

Inventors

• Schirwitz Christopher
• Erkelenz Michael
• Sämisch Birte
• Protte Rainer
• Döbler Martin
• Wenz Eckhard

Classifications

• C23C14/58

  After-treatment · CPC title

• C23C14/20

  on organic substrates · CPC title

• C08K2201/003

  Additives being defined by their diameter · CPC title

• C08K2003/385

  Binary compounds of nitrogen with boron · CPC title

• C08K7/24

  inorganic · CPC title