Glass article
A glass article includes P, Al, an alkali earth metal, F and O, wherein the content of P and O is greater at the surface side of the glass article than the inner side thereof and the content of the alkali earth metal and F is less at the surface side of the glass article than the inner side thereof.
1. A glass article containing P, Al, alkaline earth metals, F and O, wherein
contents of P and O are greater at a surface side of the glass article than an inner portion thereof,
a total content of the alkaline earth metal and a content of F are less at the surface side of the glass article than the inner portion thereof, and
the content of F is 55 anion % or more and the content of O is 45 anion % or less in the inner portion of the glass article.
2. The glass article according to claim 1 , wherein a plurality of alkaline earth metals are contained in the glass article, and a content of each respective alkaline earth metal of the plurality or alkaline earth metals contained in the glass article is less at the surface side of the glass article than the inner portion thereof.
3. The glass article according to claim 1 , wherein a content of Al is greater at the surface side of the glass article than the inner portion thereof.
4. The glass article according to claim 1 , wherein the glass article contains a rare earth element, and RE(su)/RE(in) that is a ratio of RE(su) to RE(in) is equal to or less than 3, provided that a total content of the rare earth element in the inner portion of the glass article is defined as RE(in) and a total content of the rare earth element at the surface side of the glass article is defined as RE(su), by atomic %.
5. The glass article according to claim 1 , wherein, provided that a content of O in the inner portion of the glass article is defined as O(in) and a content of O at the surface side of the glass article is defined as O(su), by atomic %, O(su)/O(in) that is a ratio of O(su) to O(in) is equal to or more than 2.0.
6. The glass article according to claim 1 , wherein a total content of Al in an oxidation state and Al in a phosphate state is greater at the surface side of the glass article than the inner portion thereof.
7. The glass article according to claim 1 , wherein a content of Al in a phosphate state is greater at the surface side of the glass article than the inner portion thereof.
8. The glass article according to claim 1 , wherein, provided that a sum of the content of Al per bond state is defined as Al(all), a content of Al in an oxidation state is defined as Al(ox), and a content of Al in a phosphate state is defined as Al(ph), by atomic %, (Al(ox) Al(ph))/Al(all) that is a ratio of a sum of Al(ox) and Al(ph) to Al(all) at the surface side is equal to or more than 0.5.
9. The glass article according to claim 1 , wherein contents of Al in an oxidation state and Al in a phosphate state are greater at the surface side of the glass article than the inner portion thereof.
10. The glass article according to claim 9 , wherein a content of alkaline earth metal in a fluorinated state is less at the surface side of the glass article than the inner portion thereof.
11. The glass article according to claim 1 , wherein the alkaline earth metal is at least one selected from a group consisting of Mg, Ca, Sr and Ba.
12. The glass article according to claim 1 , wherein a Haze value of a surface of the glass article is 1% or less.
13. The glass article according to claim 1 , wherein the glass article is an optical element.
14. The glass article according to claim 1 , wherein
the content of F is 70 anion % or more and the content of O is 30 anion % or less, in the inner portion of the glass article.
15. The glass article according to claim 1 , wherein the content of F is 80 anion % or more and the content of O is 20 anion % or less, in the inner portion of the glass article.
16. The glass article according to claim 1 , wherein the content of F is 85 anion % or more and the content of O is 15 anion % or less, in the inner portion of the glass article.
17. The glass article according to claim 1 , wherein the glass article contains
P 5+ at 1 to 35 cation %,
Al 3+ at 10 to 40 cation %,
Li + at 0 to 25 cation %,
F − at 55 to 99 anion %, and
O 2− at 1 to 45 anion %.
18. The glass article according to claim 17 , wherein
the content of P 5+ is 3 to 25 cation %,
the content of Al 3+ is more than 30 cation % and is 40 cation % or less,
the content of Li + is 0 to 20 cation %,
the content of F − is 65 to 99 anion %, and
the content of O 2− is 1 to 35 anion %.
19. The glass article according to claim 1 , wherein a total content of rare earth ion is 0.1 to 10 cation %.
20. The glass article according to claim 1 , wherein a ratio
existence
amount
of
O
(
oxygen
)
at
the
surface
side
of
the
glass
article
existence
amount
of
O
(
oxygen
)
in
the
inner
portion
of
the
glass
article
of the existence amount (atomic %) of oxygen at the surface side to the existence amount (atomic %) of oxygen at the inner portion is 2 or more, after the glass article is immersed in pure water at 16° C. for 15 hours.
21. The glass article according to claim 1 , wherein a ratio
existence
amount
of
F
(
fluorine
)
at
the
surface
side
of
the
glass
article
existence
amount
of
F
(
fluorine
)
in
the
inner
portion
of
the
glass
article
of the existence amount (atomic %) of fluorine at the surface side to the existence amount (atomic %) of fluorine in the inner portion is less than 0.7, after the glass article is immersed in pure water at 16° C. for 15 hours.