Chemical formula for vinegar. Vinegar is composed of about 5% acetic acid. This is the major chemical component of vinegar. The systematic or proper chemical name of acetic acid is ethanoic acid. Vinegar is a weak acid produced by the oxidation of alcohol (ethanol) from wines and ciders by bacteria. It has a pleasant sour taste and is used in cooking or as a condiment.
Although he fights Aizen numerous times (minor battles), this time all of the characters in Bleach are losing terribly, but the last time he fights (battles) Aizen is episodes 309 and 310.
After a few years of losing his powers, Ichigo still carries the Shinigami Representative badge with him, fights with what he learned, and now, a group of people that have powers similar to Hollows, would try to bring Ichigo's shinigami powers back.