Granted Patent B2

US 12,622,069 · App. 17/252,802 · Granted May 5, 2026

Inventors: Sarah Van Mierloo (Geleen, NL); Maud Corrina Willie Van Der Ven (Geleen, NL); Henrica Norberta Alberta Maria Steenbakkers-Menting (Geleen, NL); Roland Van Giesen (Geleen, NL)

Assignee: SABIC GLOBAL TECHNOLOGIES B.V.

H10F19/804C08K13/02H02S20/23C08K2201/014

Abstract

Claims (69)

1 . A photovoltaic element, comprising:

a transparent to light front layer,

a back layer, and

a plurality of photovoltaic cells,

which photovoltaic cells are present between the transparent to light front layer and back layer,

wherein the transparent to light front layer consists of a polypropylene composition, comprising:

a) 97.5 to 99.5 wt. % of a random polypropylene resin, based on the total weight of the polypropylene composition, wherein the random polypropylene resin has a C2 content of between 1.0 and 5.0 wt. %, based on the weight of the random polypropylene resin;

b) a mixture of light stabilizing additives; said mixture comprising:

i) a high molecular weight hindered tertiary amine light stabilizer (t-HM-HALS) having a weight average molecular weight of at least 1600 g/mol;

ii) a low molecular weight hindered secondary amine light stabilizer (s-LM-HALS) having a weight average molecular weight of below 1000 g/mol;

iii) an ultraviolet synergist, being a n-alkyl-3,5-dialkylated 4-hydroxybenzoate; and

iv) an ultraviolet absorber, being a hydroxybenzotriazole compound or a hydroxyl benzophenone compound or a mixture thereof;

c) a mixture of antioxidant additives; said mixture comprising:

i) a phenolic antioxidant; and

ii) a phosphite additive; and

d) 0 to 5 wt. % of one or more additional additives, based on the total weight of the polypropylene composition.

2 . The photovoltaic element according to claim 1 , wherein the phenolic antioxidant c)i) is 1,3,5-tris(4-t-butyl-2,6-dimethyl-3-hydroxy-benzyl)-iso-cyanurate, tetrakis[methylene-3(3′,5′-di-t-butyl-4-hydroxyphenyl)propionate]methane, or 1,3,5-trimethyl-2,4,6-tris-(3,5-di-t-butyl-4-hydroxybenzyl)benzene.

3 . The photovoltaic element according to claim 1 , wherein the high molecular weight hindered tertiary amine light stabilizer has a molecular weight (Mw) of between 1800 and 5000 g/mol.

4 . The photovoltaic element according to claim 1 , wherein the polypropylene composition further comprises the d) one or more additional additives in an amount of at most 3 wt. %, based on the total weight of the polypropylene composition.

5 . The photovoltaic element according to claim 1 , wherein the mixture of light stabilizing additives comprises as the ultraviolet synergist b)iii) n-hexadecyl 3,5-di-t-butyl-4-hydroxybenzoate and/or wherein the mixture of light stabilizing additives comprises as the ultraviolet absorber b)iv) a compound selected from the group consisting of 2-(2′-hydroxy-3′-t-butyl-5′-methylphenyl)-5-chlorobenzotriazole and 2-hydroxy-4-n-octyloxy-benzophenone.

6 . The photovoltaic element according to claim 1 , wherein the amount of said high molecular weight hindered tertiary amine light stabilizer b)i) is between 0.1 to 0.4 wt. %, based on the total weight of the polypropylene composition and/or wherein the amount of said low molecular weight hindered secondary amine light stabilizer b)ii) is between 0.1 and 1.0 wt. %, based on the total weight of the polypropylene composition and/or wherein the amount of said ultraviolet synergist b)iii) is between 0.1 and 0.5 wt. %, based on the total weight of the polypropylene composition and/or wherein the amount of said ultraviolet absorber b)iv) is between 0.1 and 0.5 wt. %, based on the total weight of the polypropylene composition.

7 . The photovoltaic element according to claim 1 , wherein the random polypropylene resin has a C2 content of 3.8 and 4.2 wt. %, based on the weight of the random polypropylene resin.

8 . The photovoltaic element according to claim 1 , wherein the random polypropylene resin has a melt flow rate measured according to ISO 1133:2005 at 230° C./2.16 kg of between 0.3 and 10.0 dg/min.

9 . The photovoltaic element according to claim 1 , wherein

the high molecular weight hindered tertiary amine light stabilizer b)i) is 1,3,5-triazine-2,4,6-triamine, N,N′″-11,2-ethanediylbis [[[4,6-bis[butyl(1,2,2,6,6-pentamethyl-4-piperidinyl)amino]-1,3,5-triazine-2-yl]imino]-3,1-propanediyl]]-bis[N′,N″-dibutyl-N′,N″-bis(1,2,2,6,6-pentamethyl-4-piperidinyl),

the low molecular weight hindered secondary amine light stabilizer b)ii) is a mixture of esters of 2,2,6,6-tetra-methyl-4-piperidinol and one or more fatty acids,

the ultraviolet synergist b)iii) is n-hexadecyl 3,5-di-t-butyl-4-hydroxybenzoate,

the ultraviolet absorber b)iv) is 2-(2′-hydroxy-3′-t-butyl-5′-methylphenyl)-5-chlorobenzotriazole,

the phenolic antioxidant c)i) is tetrakis[methylene-3(3′,5′-di-t-butyl-4-hydroxyphenyl)propionate] methane, and

the phosphite additive c)ii) is tris (2,4-di-t-butylphenyl) phosphite; and

wherein the polypropylene composition further comprises calcium stearate.

10 . The photovoltaic element according to claim 1 , wherein:

the mixture of light stabilizing additives b) is present in an amount of 0.35 to 2.2 wt. %, based on the total weight of the polypropylene composition; and

the mixture of antioxidant additives c) is present in an amount of between 0.05 and 1.0 wt. %, based on the total weight of the polypropylene composition.

11 . The photovoltaic element according to claim 1 , wherein the amount of said high molecular weight hindered tertiary amine light stabilizer b)i) is between 0.15 to 0.3 wt. %, based on the total weight of the polypropylene composition and/or wherein the amount of said low molecular weight hindered secondary amine light stabilizer b)ii) is between 0.2 and 0.6 wt. %, based on the total weight of the polypropylene composition and/or wherein the amount of said UV synergist b)iii) is between 0.2 and 0.4 wt. %, based on the total weight of the polypropylene composition and/or wherein the amount of said UV absorber b)iv) is between 0.1 and 0.2 wt. %, based on the total weight of the polypropylene composition.

12 . The photovoltaic element of claim 1 , wherein the random polypropylene resin has a C2 content of between 2.0 and 5.0 wt. %, based on the weight of the random polypropylene resin, and a melt flow rate measured according to ISO 1133:2005 at 230° C./2.16 kg of between 1.0 and 2.0 dg/min.

13 . The photovoltaic element of claim 1 , wherein the random polypropylene resin has a C2 content between 3.8 and 5.0 wt. %, based on the weight of the random polypropylene resin, and a melt flow rate measured according to ISO 1133:2005 at 230° C./2.16 kg of between 1.0 and 2.0 dg/min.

14 . A photovoltaic element, comprising:

a transparent to light front layer,

a back layer, and

a plurality of photovoltaic cells,

which photovoltaic cells are present between the transparent to light front layer and back layer,

wherein the transparent to light front layer consists of a polypropylene composition, comprising:

a) 97.5 to 99.5 wt. % of a random polypropylene resin, based on the total weight of the polypropylene composition, wherein the random polypropylene resin has a C2 content of between 2.0 and 5.0 wt. %, based on the weight of the random polypropylene resin, and a melt flow rate measured according to ISO 1133:2005 at 230° C./2.16 kg of between 1.0 and 2.0 dg/min;

b) a mixture of light stabilizing additives; said mixture comprising, based on a total weight of the polypropylene composition:

i) 0.1 to 0.4 wt. % of a high molecular weight hindered tertiary amine light stabilizer (t-HM-HALS) having a weight average molecular weight of at least 1600 g/mol;

ii) 0.1 to 1.0 wt. % of a low molecular weight hindered secondary amine light stabilizer (s-LM-HALS) having a weight average molecular weight of below 1000 g/mol;

iii) 0.1 to 0.5 wt. % of an ultraviolet synergist, being n-hexadecyl 3,5-di-t-butyl-4-hydroxybenzoate; and

iv) 0.1 to 0.5 wt. % of an ultraviolet absorber, being 2-(2′-hydroxy-3′-t-butyl-5′-methylphenyl)-5-chlorobenzotriazole, 2-hydroxy-4-n-octyloxy-benzophenone, or a combination thereof;

c) a mixture of antioxidant additives; said mixture comprising:

i) a phenolic antioxidant, which is 1,3,5-tris(4-t-butyl-2,6-dimethyl-3-hydroxy-benzyl)-iso-cyanurate, tetrakis[methylene-3(3′,5′-di-t-butyl-4-hydroxyphenyl)propionate]methane, or 1,3,5-trimethyl-2,4,6-tris-(3,5-di-t-butyl-4-hydroxybenzyl)benzene; and

ii) a phosphite additive; and

d) 0 to 5 wt. % of one or more additional additives, based on the total weight of the polypropylene composition.

15 . The photovoltaic element according to claim 14 , wherein

the high molecular weight hindered tertiary amine light stabilizer b)i) is 1,3,5-triazine-2,4,6-triamine, N,N′″-11,2-ethanediylbis [[[4,6-bis[butyl(1,2,2,6,6-pentamethyl-4-piperidinyl)amino]-1,3,5-triazine-2-yl]imino]-3,1-propanediyl]]-bis[N′,N″-dibutyl-N′,N″-bis(1,2,2,6,6-pentamethyl-4-piperidinyl),

the low molecular weight hindered secondary amine light stabilizer b)ii) is a mixture of esters of 2,2,6,6-tetra-methyl-4-piperidinol and one or more fatty acids,

the ultraviolet synergist b)iii) is n-hexadecyl 3,5-di-t-butyl-4-hydroxybenzoate,

the ultraviolet absorber b)iv) is 2-(2′-hydroxy-3′-t-butyl-5′-methylphenyl)-5-chlorobenzotriazole,

the phenolic antioxidant c)i) is tetrakis[methylene-3(3′,5′-di-t-butyl-4-hydroxyphenyl)propionate] methane, and

the phosphite additive c)ii) is tris (2,4-di-t-butylphenyl) phosphite.

16 . The photovoltaic element of claim 15 , wherein the polypropylene composition further comprises calcium stearate.

17 . The photovoltaic element of claim 14 , wherein

the amount of said high molecular weight hindered tertiary amine light stabilizer b)i) is between 0.15 to 0.3 wt. %, based on the total weight of the polypropylene composition,

the amount of said low molecular weight hindered secondary amine light stabilizer b)ii) is between 0.2 and 0.6 wt. %, based on the total weight of the polypropylene composition,

the amount of said UV synergist b)iii) is between 0.2 and 0.4 wt. %, based on the total weight of the polypropylene composition, and

the amount of said UV absorber b)iv) is between 0.1 and 0.2 wt. %, based on the total weight of the polypropylene composition.

18 . The photovoltaic element of claim 14 , wherein the mixture of antioxidant additives c) is present in an amount of between 0.05 and 1.0 wt. %, based on the total weight of the polypropylene composition.

19 . The photovoltaic element of claim 14 , wherein a weight ratio of b)i) to b)ii) to b)iii) to b)iv) is about 2:4:2:1.

20 . The photovoltaic element of claim 14 , wherein a weight ratio of c)i) to c)ii) is about 1:2.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (16)