Claims
- 1. A water-reducing agent for cement, comprising a condensate prepared by reacting a bisphenol compound of the formula (I) ##STR10## wherein X indicates a member selected from the group consisting of a covalent bond, ##STR11## --O--and mixtures thereof, R.sub.1, R.sub.2 and R.sub.3 each independently is hydrogen or alkyl and R.sub.4 is alkylene, or salts thereof, with a compound having the formula (II) ##STR12## wherein Y is hydrogen or alkyl, or salts thereof, and with formaldehyde in the presence of an alkali catalyst at a pH of from 7 to 12, wherein said bisphenol is present in an amount of from 20 to 150 parts by weight and said formaldehyde is present in an amount of from 20 to 65 parts by weight, relative to 100 parts by weight of said aromatic aminosulfonic acid, and said condensate has a weight-average molecular weight of from 10,000 to 50,000.
- 2. The water-reducing agent of claim 1, wherein R.sub.1, R.sub.2 and R.sub.3 each independently is hydrogen or methyl, R.sub.4 is (CH.sub.2).sub.2 and Y is hydrogen.
- 3. The water-reducing agent of claim 1, wherein said reacting is conducted by adding said formaldehyde to a mixture of said bisphenol compound, said aromatic aminosulfonic acid compound and said alkali catalyst, then heating said formaldehyde and said mixture at a temperature of from 60.degree. to 110.degree. C. over a period of time of from 4 to 20 hours.
- 4. The water-reducing agent of claim 3, wherein said formaldehyde is added to said mixture of said bisphenol compound, said aromatic aminosulfonic acid compound and said alkali catalyst dropwise over a period of time of from ob 1 to 3 hours.
- 5. The water-reducing agent of claim 1, wherein said bisphenol compound having the formula (I) is selected from the group consisting of 2,2-bis(4-hydroxyphenyl)propane, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenylmethane, 4,4-bis(4-hydroxyphenyl)valeric acid, 4,4-bis (4-hydroxyphenyl)-butyric acid, 4,4'-dihydroxydiphenylether and 4,4'-dihydroxybiphenyl.
- 6. The water-reducing agent of claim 3, wherein said alkali catalyst is selected from the group consisting of sodium hydroxide, calcium hydroxide, potassium hydroxide and ammonium hydroxide.
- 7. The water-reducing agent of claim 1, comprising from 80 to 20 parts by weight of said condensate, and further comprising form 20 to 80 parts by weight of a lignin sulfonate obtained from a sulfite pulp spent liquor which is treated by ultrafiltration until the content of reducible sugars is not more than 5%, said lignin sulfonate having not less than 0.2 mol of carboxyl groups and not less than 0.10 mol of sulfonate groups per mol of phenylpropane units.
- 8. The water-reducing agent of claim 7, wherein said ultrafiltration has a fractionation membrane for a molecular weight of from 1,000 to 30,000.
- 9. The water-reducing agent of claim 1, having the formula (III): ##STR13## wherein n is an integer of 1 to 20.
- 10. The water-reducing agent of claim 4, wherein said alkali catalyst is present in from 0.5 to 2.0 mol equivalents with respect to 1 mol of said aromatic aminosulfonic acid compound.
- 11. The water-reducing agent of claim 10, wherein said aromatic aminosulfonic acid compound is 4-aminobenzenesulfonic acid, said aromatic aminosulfonic acid compound and said bisphenol are present in a ratio of 1/1, and said alkali catalyst is added at a rate maintaining from 0.95 to 1.05 mol equivalents with respect to 1 mol of said aromatic aminosulfonic acid compound.
Priority Claims (5)
Number |
Date |
Country |
Kind |
1-227082 |
Sep 1989 |
JPX |
|
1-279229 |
Oct 1989 |
JPX |
|
1-279230 |
Oct 1989 |
JPX |
|
1-344656 |
Dec 1989 |
JPX |
|
2-63525 |
Mar 1990 |
JPX |
|
Parent Case Info
The present application is a divisional of application Ser. No. 566,760, filed Aug. 14, 1990, now U.S. Pat. No. 5,153,299.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4936918 |
Furuhashi et al. |
Jun 1990 |
|
5092934 |
Furuhashi et al. |
Mar 1992 |
|
Foreign Referenced Citations (3)
Number |
Date |
Country |
54-030983 |
Mar 1979 |
JPX |
59-091195 |
May 1984 |
JPX |
1-113419 |
May 1989 |
JPX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
566760 |
Aug 1990 |
|