Increasing the time to maturity and decreasing the coupon rate will increase the interest rate risk of a bond.

Interest rate risk refers to the risk that the value of a bond will fluctuate due to changes in the general level of interest rates. Bonds with longer maturities and lower coupon rates are more sensitive to interest rate changes, thus increasing their interest rate risk. This is because the longer time frame until maturity means there is a greater period during which rates can change, and lower coupon payments mean investors have to wait longer to recoup their initial investment, making the bond's price more sensitive to rate changes.