Abstract This invention relates to the preparation of glasses exhibiting low transition temperatures with excellent chemical durability. The glasses consist essentially, in mole %, of: ______________________________________ P 2 O 5 44-58 Al 2 O 3 +
4-10 Na 2 O + Li 2 O
10-45
B 2 O 3 Al 2 O 3 0-7 Na 2 O
10-30 Cu 2 O
0-20
B 2 O 3 0-10 Li 2 O
0-30 Li 2 O + Cu 2 O
10-30
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A glass exhibiting a transition temperature below 350° C., a working temperature below 450° C., and excellent resistance to attack by water and mild aqueous alkaline solutions, said glass consisting essentially, expressed in terms of mole percent on the oxide basis, of: ______________________________________
P.sub.2 O.sub.5
41-57 Li.sub.2 O 0-21
Al.sub.2 O.sub.3
0-5 Na.sub.2 O + Li.sub.2 O
13.8-43
B.sub.2 O.sub.3
0-9 Cu.sub.2 O 0-12
Al.sub.2 O.sub.3 + B.sub.2 O.sub.3
3-9.5 Li.sub.2 O + Cu.sub.2 O
10-29
Na.sub.2 O 15-24 ZrO.sub.2 0-2.8
CaO 0-8 F.sub.2 0-5.5
MgO 0-2 K.sub.2 O 0-5.5
P.sub.2 O.sub.5 + Al.sub.2 O.sub.3 + B.sub.2 O.sub.3 + Na.sub.2 O +
Li.sub.2 O + Cu.sub.2 O >90 .--
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Claim 2
Dependent Claim
110 words
A glass exhibiting a transition temperature below 350° C., a working temperature below 450° C., and excellent resistance to attack by water and mild aqueous alkaline solutions, said glass consisting essentially, expressed in terms of mole percent on the oxide basis, of: ______________________________________
P.sub.2 O.sub.5
41-57 Li.sub.2 O 0-21
Al.sub.2 O.sub.3
0-5 Na.sub.2 O + Li.sub.2 O
13.8-43
B.sub.2 O.sub.3
0-9 Cu.sub.2 O 0-12
Al.sub.2 O.sub.3 + B.sub.2 O.sub.3
3-9.5 Li.sub.2 O + Cu.sub.2 O
10-29
Na.sub.2 O 15-24 ZrO.sub.2 0-2.8
CaO 0-8 F.sub.2 0-5.5
MgO 0-2 K.sub.2 O 0-5.5
P.sub.2 O.sub.5 + Al.sub.2 O.sub.3 + B.sub.2 O.sub.3 + Na.sub.2 O +
Li.sub.2 O + Cu.sub.2 O >90 .--
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