Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
128 words
Alkali-resistant glass fibres formed from a glass composition consisting essentially of, in weight percentages: ______________________________________
SiO.sub.2 50 to 75%
ThO.sub. 2 + ZrO.sub.2
5 to 30% with ThO.sub.2 being in the
range of at least 0.4% up to 4%
R.sub.2 O 0 to 25%
R'O 0 to 40%
R.sub.2 O + R'O
10 to 40%
Rare earth oxides
0 to 20%
TiO.sub.2 0 to 10%
______________________________________ the content of ThO 2 being at least 1% when the content of ZrO 2 is less than 6%, where R 2 O represents Na 2 O, K 2 O or Li 2 O, with K 2 O not exceeding 10% and Li 2 O not exceeding 5% and R'O represents one or more of MgO, CaO, SrO, BaO, ZnO and MnO.
Claim 2
Dependent Claim
128 words
Alkali-resistant glass fibres formed from a glass composition consisting essentially of, in weight percentages: ______________________________________
SiO.sub.2 50 to 75%
ThO.sub. 2 + ZrO.sub.2
5 to 30% with ThO.sub.2 being in the
range of at least 0.4% up to 4%
R.sub.2 O 0 to 25%
R'O 0 to 40%
R.sub.2 O + R'O
10 to 40%
Rare earth oxides
0 to 20%
TiO.sub.2 0 to 10%
______________________________________ the content of ThO 2 being at least 1% when the content of ZrO 2 is less than 6%, where R 2 O represents Na 2 O, K 2 O or Li 2 O, with K 2 O not exceeding 10% and Li 2 O not exceeding 5% and R'O represents one or more of MgO, CaO, SrO, BaO, ZnO and MnO.
Claim 3
Dependent Claim
26 words
Glass fibres according to claim 1, wherein the R 2 O content is between 10 and 25% and the R'O content is from 0 to 15%.
Claim 4
Dependent Claim
26 words
Glass fibres according to claim 1, wherein the R 2 O content is from 0 to 10% and the R'O content is between 15 and 40%.
Claim 5
Dependent Claim
20 words
Glass fibres according to claim 1, wherein the glass composition further comprises up to 20% Al 2 O 3 .
Claim 6
Dependent Claim
20 words
Glass fibres according to claim 1, wherein the glass composition further comprises up to 10% B 2 O 3 .
Claim 7
Dependent Claim
20 words
Glass fibres according to claim 1, wherein the glass composition further comprises up to 5% Fe 2 O 3 .
Claim 8
Dependent Claim
16 words
Glass fibres according to claim 1, wherein the glass composition further comprises up to 2% F.
Claim 9
Dependent Claim
72 words
Glass fibres according to claim 2 formed from a glass composition consisting essentially of, in weight percentages: ______________________________________
SiO.sub.2 51 to 73%
ZrO.sub.2 9 to 21%
ThO.sub.2 0.5 to 2.5%
R.sub.2 O 10 to 21%
R'O 0 to 13%
Rare earth
oxides 4 to 18%
F.sub.2 0 to 2%
______________________________________ with K 2 O not exceeding 5% and Li 2 O not exceeding 3% and R 2 O+R'O from 14% to 30%.
Claim 10
Dependent Claim
13 words
Glass fibres according to claim 8, wherein CaO is the principal R'O constituent.
Claim 11
Dependent Claim
24 words
Glass fibres according to claim 8 wherein ZrO 2 exceeds 18%, R 2 O is at least 14% and R'O does not exceed 3%.
Claim 12
Dependent Claim
14 words
A fibre-reinforced cementitious product containing, as reinforcement, alkali-resistant glass fibres according to claim 2.
Claim 13
Dependent Claim
25 words
A cementitious product according to claim 11, wherein the glass fibres constitute from 2 to 10% by weight of the total solids in the product.
Claim 14
Dependent Claim
20 words
A cementitious product according to claim 12, wherein the glass fibres constitute substantially 5% by weight of the total solids.