No, large cap equity funds are not tax free. The returns on such funds are taxable as per the following rules:
For a holding period of less than 1 year: 15% Short Term Capital Gain Tax is levied.
For a holding period of more than 1 year: 10% Long Term Capital Gain Tax is levied. However, if LTCG is less than Rs. 1 lakh in a financial year, then the returns are exempt from tax.