Controlled release of additives in fluid systems

A container for releasing a chemical additive in a fluid material selected from the group consisting of a liquid lubricant composition and a hydraulic fluid composition, the container comprising:

• a fluid material-impermeable casing defining a substantially hollow interior and at least one opening;
• a fluid material additive composition provided in the interior of the casing, the fluid material additive composition comprising a gel chemical additive effective to provide a benefit to and soluble in a fluid material selected from the group consisting of a liquid lubricant composition and a hydraulic fluid composition;
• and
• at least one fluid material-permeable element provided at or near the opening of the casing and effective to provide for release of a portion of the gel chemical additive into the fluid material in contact with the casing.