Coloured soda-lime glass

1. Coloured soda-lime glass which comprises principal glass-forming constituents and colouring agents:

total iron in a quantity which, expressed in weight of the oxide Fe 2 0 3 in relation to the total weight of glass, is greater than or equal to 0.5% and less than or equal to 0.848%;

ferrous iron in a quantity which, expressed in weight of atoms of Fe 2+ in relation to total weight of iron atoms present in the glass (ratio of Fe 2+ /total Fe), lies in the range of between 20% and 65%;

cerium in a quantity which, expressed in weight of CeO 2 in relation to the total weight of glass, is greater than or equal to 0.1%;

titanium in a quantity which, expressed in weight of TiO 2 in relation to the total weight of glass, is greater than or equal to 0% and less than 0.2%;

the coloured soda-lime glass being free of selenium,

and the glass has:

a light transmission, measured for illuminant A and calculated for a thickness of 4 mm (TLA4), which lies in the range of between 15% and 55%;

a total transmission in the ultraviolet measured for a thickness of 4 mm (TUV4) of less than or equal to 30%; and

a dominant wavelength in transmission (λ D ) of less than or equal to 491 nm.

2. Coloured soda-lime glass according to claim 1 , characterised by at least one of the following (A) through (I):

(A) the quantity of total iron is further defined as being:

(i) less than 0.848%

(ii) at least 0.70%

(iii) at least 0.75%;

(iv) (i) and (ii); or

(v) (i) and (iii);

(B) the quantity of cerium is further defined as being:

(i) greater than 0.10%;

(ii) greater than 0.15%;

(iii) less than or equal to 0.50%; or

(iv) (ii) and (iii);

(C) the quantity of titanium is further defined as being:

(i) less than 0.15%; or

(ii) less than 0.10%;

(D) cobalt is present as a colouring agent in a quantity which, expressed in weight of Co in relation to the total weight of glass, is:

(i) greater than 75 ppm;

(ii) greater than 100 ppm;

(iii) less than or equal to 350 ppm;

(iv) less than or equal to 250 ppm;

(v) (i) and (iv); or

(vi) (ii) and (iii);

(E) chromium is present as a colouring agent in a quantity which, expressed in weight of Cr 2 0 3 in relation to the total weight of glass, is:

(i) at least 5 ppm;

(ii) at least 50 ppm;

(iii) at least 100 ppm;

(iv) less than 1000 ppm;

(v) less than 500 ppm;

(vi) less than or equal to 500 ppm; or

(vii) (iii) and (v);

(F) the quantity of Fe 2+ is further defined being:

(i) within the range of between 35% and 55%; or

(ii) within the range of between 40% and 50%;

(G) TLA4 is further defined as being:

(i) within the range of between 20% and 45%; or

(ii) within the range of between 25% and 35%;

(H) TUV4 is further defined as being:

(i) less than or equal to 25%; or

(ii) less than or equal to 20%;

(I) λD is further defined as being:

(i) less than or equal to 489 nm, or

(ii) less than or equal to 487 nm.

3. Coloured soda-lime glass according to claim 2 , further characterised by at least two of the aforementioned features (A) through (I).

4. Coloured soda-lime glass according to claim 2 , further characterised by at least three of the aforementioned features (A) through (I).

5. Coloured soda-lime glass according to claim 2 , further characterised by at least four of the aforementioned features (A) through (I).

6. Coloured soda-lime glass according to claim 2 , further characterised by all of the aforementioned features (A) through (I).

7. Coloured soda-lime glass according to claim 2 , characterised by at least one of the following (J) through (M):

(J) vanadium is present as a colouring agent in a quantity which, expressed in weight of V 2 O 5 in relation to the total weight of glass, is:

(i) less than 1000 ppm; or

(ii) less than 500 ppm;

(K) the glass has an energy transmission measured according to the Moon distribution and calculated for a thickness of 4 mm (TE4) of:

(i) less than 45%;

(ii) less than 35%; or

(iii) less than 25%;

(L) the glass has a selectivity (SE4) which is:

(i) greaterthan 1.0;or

(ii) greater than 1.1;

(M) the glass has an excitation purity in transmission which is:

(i) greater then 10% or

(ii) greater than 15%.

8. Coloured soda-lime glass according to claim 7 , further characterised by at least two of the aforementioned features (J) through (M).

9. Coloured soda-lime glass according to claim 7 , further characterised by at least three of the aforementioned features (J) through (M).

10. Coloured soda-lime glass according to claim 7 , further characterised by all of the aforementioned features (J) through (M).

11. Coloured soda-lime glass according to claim 2 , further characterised in that the colouring agents consist essentially of iron, cerium, titanium and cobalt.

12. Coloured soda-lime glass according to claim 2 , further characterised in that the colouring agents consist of iron, cerium, titanium and cobalt.

13. Coloured soda-lime glass according to claim 2 , further characterised in that the colouring agents consist essentially of iron, cerium, titanium, cobalt and chromium.

14. Coloured soda-lime glass according to claim 2 , further characterised in that the colouring agents consist of iron, cerium, titanium, cobalt and chromium.

15. Coloured soda-lime glass according to claim 1 , characterised by at least one of the following (J) through (M):

(J) vanadium is present as a colouring agent in a quantity which, expressed in weight of V205 in relation to the total weight of glass, is:

(i) less than 1000 ppm; or

(ii) less than 500 ppm;

(K) the glass has an energy transmission measured according to the Moon distribution and calculated for a thickness of 4 mm (TB4) of:

(i) less than 45%;

(ii) less than 35%; or

(iii) less than 25%;

(L) the glass has a selectivity (SE4) which is:

(i) greater than 1.0;or

(ii) greater than 1.1;

(M) the glass has an excitation purity in transmission which is:

(i) greater then 10% or

(ii) greater than 15%.

16. Coloured soda-lime glass according to claim 15 , further characterised by at least two of the aforementioned features (J) through (M).

17. Coloured soda-lime glass according to claim 15 , further characterised by at least three of the aforementioned features (J) through (M).

18. Coloured soda-lime glass according to claim 15 , further characterised by all of the aforementioned features (J) through (M).

19. Coloured soda-lime glass according to claim 1 , characterised in that it is covered by a layer.