← Back to Patent Explorer
US3960582A Expired / Lapsed US ⏱️ 0.0 years remaining

Low porosity cement and process for producing same

Assignee: Westvaco Corp
•
Filing: 1975-04-21
•
Granted: 1976-06-01
•
Expires: 1995-04-21
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method is disclosed for making low-porosity, free-flowing cement pastes with extended set times, improved workability and reduced expansion due to alkali aggregate reactions by combining hydraulic cements, especially portland-type cements, ground without gypsum with from 0.1 to about 1.0% of an alkali or alkaline earth lignosulfonate or sulfonated lignin, and 0.1 to 2.0% of an alkali bicarbonate, and combining with 20 to 40% water. Mixtures of aggregates with such low-porosity pastes made according to this process produce very workable mortars and concretes with extended set times and upon hardening have reduced expansion.

Inventors

  • 👤 Frank J. Ball
  • 👤 David V. Braddon
  • 👤 Lynden J. Stryker

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 20:59
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/02

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 66 words
A method of making a free-flowing cement paste which comprises; a. combining ground hydraulic cement without gypsum with from 0.1 to about 1.5% of alkali or alkaline earth lignosulfonate or sulfonated lignin and from 0.1 to about 2.0% of an alkali bicarbonate, and b. mixing the combined materials from (a) with 20 to 40% of water, all percentages based on the dry weight of ground cement.
Claim 2
Independent Claim 66 words
A method of making a free-flowing cement paste which comprises; a. combining ground hydraulic cement without gypsum with from 0.1 to about 1.5% of alkali or alkaline earth lignosulfonate or sulfonated lignin and from 0.1 to about 2.0% of an alkali bicarbonate, and b. mixing the combined materials from (a) with 20 to 40% of water, all percentages based on the dry weight of ground cement.
Claim 3
Dependent Claim 18 words
The method according to claim 1 wherein said lignin is present in an amount from 0.3 to 0.8%.
Claim 4
Dependent Claim 19 words
The method according to claim 1 wherein said alkali bicarbonate is present in an amount from 0.7 to 1.5%.
Claim 5
Dependent Claim 28 words
The method according to claim 1 wherein said alkali bicarbonate is sodium bicarbonate, said lignin is a sulfonated alkali lignin, and said hydraulic cement is a portland cement.
Claim 6
Independent Claim 71 words
A method of making a free-flowing cement paste which comprises; a. combining ground hydraulic cement without gypsum with from 0.1 to about 2.0% of an alkali bicarbonate, b. combining 20 to 40% of water with from 0.1 to about 1.5% of alkali or alkaline earth lignosulfonate or sulfonated lignin, and c. thereafter mixing together the combined materials of steps (a) and (b), all percentages based on dry weight of ground cement.
Claim 7
Independent Claim 71 words
A method of making a free-flowing cement paste which comprises; a. combining ground hydraulic cement without gypsum with from 0.1 to about 2.0% of an alkali bicarbonate, b. combining 20 to 40% of water with from 0.1 to about 1.5% of alkali or alkaline earth lignosulfonate or sulfonated lignin, and c. thereafter mixing together the combined materials of steps (a) and (b), all percentages based on dry weight of ground cement.
Claim 8
Dependent Claim 18 words
The method according to claim 5 wherein said lignin is present in an amount from 0.3 to 0.8%.
Claim 9
Dependent Claim 26 words
The method according to claim 5 wherein a portion of said lignin is added to the water, and the remaining lignin is combined with the cement.
Claim 10
Dependent Claim 19 words
The method according to claim 5 wherein said alkali bicarbonate is present in an amount from 0.7 to 1.5%.
Claim 11
Dependent Claim 28 words
The method according to claim 5 wherein said alkali bicarbonate is sodium bicarbonate, said lignin is a sulfonated alkali lignin and said hydraulic cement is a portland cement.
Claim 12
Dependent Claim 83 words
A low porosity aggregate containing cement composition which comprises; a. a portland cement having a Blaine fineness above about 3,500 containing substantially no calcium sulfate. b. alkali bicarbonate in an amount from 0.1 to 2.0% by weight based on dry ground cement, and c. an alkali or alkaline earth lignosulfonate or sulfonated lignin in an amount of from 0.1 to 1.0% by weight based on ground cement, said aggregate-containing cement composition having been made at a water-to-cement ratio of between 0.4 and 0.2.
Claim 13
Dependent Claim 83 words
A low porosity aggregate containing cement composition which comprises; a. a portland cement having a Blaine fineness above about 3,500 containing substantially no calcium sulfate. b. alkali bicarbonate in an amount from 0.1 to 2.0% by weight based on dry ground cement, and c. an alkali or alkaline earth lignosulfonate or sulfonated lignin in an amount of from 0.1 to 1.0% by weight based on ground cement, said aggregate-containing cement composition having been made at a water-to-cement ratio of between 0.4 and 0.2.
Claim 14
Dependent Claim 42 words
The aggregate containing cement composition of claim 10 wherein said alkali bicarbonate is sodium bicarbonate and is present in an amount from 0.7 to 1.5%, and said lignin is an alkali lignin and is present in an amount from 0.3 to 0.8%.

References Cited (Backward Citations)

US3689294A Cited
US3782984A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-06-01 1979-12-01 1980-06-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-06-01 1983-12-01 1984-06-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-06-01 1987-12-01 1988-06-01 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag