The Commissioner of Revenue Services shall grant a credit against any tax due under the provisions of chapter 207, 208, 209, 210, 211 or 212 in an amount not to exceed sixty per cent of the total cash amount invested during the taxable year by the business firm in programs operated or created pursuant to proposals approved pursuant to § 12-632 for planning, site preparation, construction, renovation or acquisition of facilities for purposes of establishing a child care center, as described in § 19a-77, to be used primarily by the children of such business firm’s employees and equipment installed for such center, including kitchen appliances, to the extent that such equipment or appliances are necessary in the use of such center for purposes of child care services, provided: (1) Such center is operated under the authority of a license issued by the Commissioner of Early Childhood in accordance with sections 19a-77 to 19a-87, inclusive, (2) such center is operated without profit by such business firm related to any charges imposed for the use of such center for purposes of child care services, and (3) the amount of tax credit allowed any business firm under the provisions of this section for any income year may not exceed fifty thousand dollars. If two or more business firms share in the cost of establishing such a center for the children of their employees, each such taxpayer shall be allowed such credit in relation to the respective share, paid or incurred by such taxpayer, of the total expenditures for the center in such income year. The commissioner shall not grant a credit pursuant to this section to any taxpayer claiming a credit for the same year pursuant to § 12-217x.