PURPOSE: To provide a condensate available for an admixture for giving concrete excellent in fluidity by polymerizing lignin sulfonic acid (salt), sulfanilic acid (salt) and formaldehyde at a specified weight ratio.
CONSTITUTION: 50-95 pts.wt. lignin sulfonic acid (salt), 2-40 pts.wt. sulfanilic acid (salt) and 1-15 pts.wt. formaldehyde are polymerized by heating them in the aqueous conditions to produce lignin sulfonic acid-sulfanilic acid- formaldehyde condensate. The obtained condensate is added as an admixture in the case of producing concrete, mortar or cement paste. Thereby, since entrained air bubbles are diminished by this admixture, a suitable air entraining agent is combined. Freezing and thawing resistance is enhanced by entraining fine air bubbles. Furthermore, delay of the setting time of cement composition is prevented and fluidity is enhanced and deterioration of fluidity based on elapse of time is reduced.
KASUGA SHINOBU
YAMASHITA TETSUO
TAKAHASHI YUJI
TAKEUCHI TORU
KAWADA KAZUSHIGE
