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US-12617936-B2 - Laser printable polymeric compositions

US12617936B2US 12617936 B2US12617936 B2US 12617936B2US-12617936-B2

Abstract

A polymeric composition includes an ethylene polymer, 0.05 wt % to 0.25 wt % carbon black based on a total weight of the polymeric composition and a polymeric ultraviolet light stabilizer including a hindered amine moiety and having a weight average molecular weight from 5,000 g/mol to 20,000 g/mol as measured according to Gel Permeation Chromatography.

Inventors

  • STACEY A. SABA
  • Paul J. Brigandi
  • Mohamed Esseghir
  • Bharat I. Chaudhary

Assignees

  • DOW GLOBAL TECHNOLOGIES LLC

Dates

Publication Date
20260505
Application Date
20210726

Claims (9)

  1. 1 . A polymeric composition comprising: 95 wt % or greater of an ethylene polymer based on a total weight of the polymeric composition; 0.1 wt % to 0.19 wt % carbon black based on a total weight of the polymeric composition; and 0.25 wt % to 2 wt % of a polymeric ultraviolet light stabilizer based on a total weight of the polymeric composition, the polymeric ultraviolet light stabilizer comprising a hindered amine moiety and having a weight average molecular weight from 8,000 g/mol to 12,000 g/mol as measured according to Gel Permeation Chromatography.
  2. 2 . The polymeric composition of claim 1 , wherein the ethylene polymer has a density of from 0.919 g/cc to 0.950 g/cc as measured by ASTM D792.
  3. 3 . The polymeric composition of claim 1 , wherein the polymeric composition further comprises: an oligomer ultraviolet light stabilizer having a weight average molecular weight of from 1,000 g/mol to 5,000 g/mol as measured according to Gel Permeation Chromatography.
  4. 4 . The polymeric composition of claim 3 , wherein the polymeric composition comprises from 0.25 wt % to 1.0 wt % of the oligomer ultraviolet light stabilizer based on a total weight of the polymeric composition.
  5. 5 . The polymeric composition of claim 4 , wherein the oligomer ultraviolet light stabilizer has a chemical abstract services registration number of 136504-96-6 or 71878-19-8.
  6. 6 . The polymeric composition of claim 1 , wherein the polymeric ultraviolet light stabilizer has a chemical abstract services registration number of 136504-96-6.
  7. 7 . The polymeric composition of claim 1 , wherein the ethylene polymer is unimodal.
  8. 8 . The polymeric composition of claim 7 , wherein the ethylene polymer is free of silane-functionalization.
  9. 9 . A coated conductor comprising: a conductor; and the polymeric composition of claim 1 disposed at least partially around the conductor.

Description

BACKGROUND Field of the Disclosure The present disclosure relates to compositions, and more specifically, to polymeric compositions that are laser printable. Introduction Laser beam printing is a method used in the marking of polymeric compositions. Laser beam printing is useful because no printing ink or physical contact between the polymeric composition and the printer are required. Further, the process of laser beam printing is fast and simple and can provide a marking of good durability. Not every polymeric composition can be laser printed. For example, polymeric compositions often require specific additives and compositions in order to be rendered laser printable. The requirements to render a polymeric composition laser printable may be in conflict with the design of the polymeric composition based on its end use. For example, conventional wire and cable jacketing may include carbon black in concentrations from about 2 weight percent to 3 weight percent to ensure 50% retention of elongation at break after 2000 hours of accelerated ultraviolet exposure. Unfortunately, conventional carbon black concentrations of about 2 weight percent to 3 weight percent lead to insufficient contrast (i.e., 25% contrast or less) when laser printing. Others have attempted to solve the afore mentioned issue by replacing carbon black with ultraviolet (“UV”) light stabilizers. For example, European Patent Office Patent Publication Number EP0710570A1 (“'570 publication”) discloses a grouping of UV light stabilizers that allow for low carbon black concentrations and provide a laser printable jacketing. The disclosed UV light stabilizers of the '570 publication are (a) a dimethyl succinate polymer with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidine ethanol, (b) 2-(2′-hydroxy-5′-t-butylphenyl)-3-chlorobenzotriazole, (c) 2-hydroxy-4-m-octoxybenzophenone, (d) N,N′-bis(2,2,6,6-tetramethyl-4-piperidinyl)-1,6-hexanediamine polymer with 2,4,6-trichloro-1,3,5-triazine and 2,4,4-trimethyl-1,2-pentanamine, (e) 2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)-5-chlorobenzotriazole, (f) bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, and (g) 2H-1-benzopyran-2-one, 7-(2H-naphtho[1,2D]triazol-2-yl)-3-phenyl. The disclosed UV light stabilizers of the '770 publication are either small molecules or oligomeric in nature. For example, UV light stabilizers (b), (c), (e), (f) and (g) are all small molecules whereas (a) has a number average molecular weight (Mn) from 3100 to 4000 and (d) has an Mn of 2000 to 3100 rendering (a) and (d) oligomeric. As demonstrated in Table 5 of the '570 publication, example 17A utilizing oligomeric UV light stabilizer (a) is able to produce a polymeric composition that can withstand accelerated UV light exposure with less than 2 weight percent but greater than 0.3 weight percent carbon black. However, Table 3 of the '570 publication demonstrates oligomeric UV light stabilizer (a) fails to reach a grey contrast above 25% at carbon black levels of 0.3 weight percent or greater. These results suggest that the use of polymeric ultraviolet light stabilizers comprising a hindered amine moieties require a compromise between compositions that withstand accelerated UV light exposure and laser printable compositions. Another attempt in the art to solve the issues related to laser printing wire and cable jacketing is provided by World Intellectual Property Organization Publication Number WO2019068815A1 (“'815 publication”) and utilizes carbon black and a synergistic blend of oligomeric hindered amine UV light stabilizers. The '815 publication discloses the use of a synergistic mixture of UV light stabilizers (a) and (d) of the '570 publication in a polymeric composition, but requires at least a 0.25 weight percent carbon black concentration to retain the mechanical properties of the polymeric composition after accelerated UV exposure. In view of the combined art's inability to achieve a polymeric composition utilizing less than 0.25 weight percent carbon black through the addition of an oligomeric hindered amine light stabilizer, it would be surprising to discover a polymeric composition that comprises 0.05 wt % to 0.25 wt % of carbon black and a polymeric ultraviolet light stabilizer having a weight average molecular weight from 5,000 g/mol to 20,000 g/mol as measured according to Gel Permeation Chromatography that is laser printable (i.e., grey contrast of greater than 25%) and retains 50% or more of its elongation at break after 2000 hours of accelerated ultraviolet exposure. SUMMARY OF THE DISCLOSURE The inventors of the present application have surprisingly discovered that the use of a polymeric ultraviolet light stabilizer comprising a hindered amine moiety and having a weight average molecular weight from 5,000 g/mol to 20,000 g/mol as measured according to Gel Permeation Chromatography enables the formation of a polymeric composition having 0.05 weight percent to 0.25 weight percent carbon black that is laser printable (i.e., grey