Лако-красочные материалы — производство

The zinc phosphate materials, discussed in Section II. B.1 as luting agents, are also in use for cavity lining. The major difference, compared to the luting cements, is the more putty­like consistency required for base or lining purposes and brought about by increasing the powder/liquid ratio to, maximally, 3.2g/mL. A cement of this composition sets in 7 min or less to a hardness sufficient for amalgam filling without liner displacement, and the ulti­mate compressive strength may be as high as 140 MPa. Retention to the adherends, as in the luting application, utilizes micromechanical interlocking. The cements provide good thermal insulation, but the chemical barrier properties of these inherently acidic materials are poor. The former feature is beneficial, and the latter acceptable, for restoration with amalgam.