No.
Corporate tax is on the net income.  If the contractor is working for his corporation on salary, he pays the same personal income tax as any employee for his salary. The salary is a deduction for the company.   If he is paid in divdends, then corporate tax is paid on the entire corporate net income, and he also pays personal tax on his dividend, which brings the total tax up to what he would have paid if he was taking a salary.
.After corporate tax is paid, he has $85000 left in retained earnings.  He invests the retained earnings.  The Corporate tax he will pay in the future is on the interest earned on the $85,000, not on the principle.