The invention relates to a I-type
crystal of dibenzenesulfonate of an inhibitor of
protein tyrosine kinase. Specifically, the invention relates to a I-type
crystal of
lapatinib dibenzenesulfonate. The
crystal, radiated by Cu-K<alpha>, has the following characteristic peaks, represented by a 2theta angle and an inter-planar distance in an X-
ray powder diffraction pattern: 6.21(14.23), 10.02(8.82), 12.11(7.30), 13.26(6.67), 13.55(6.53), 13.79(6.42), 14.88(5.95), 6.70(5.31), 17.59(5.04), 18.26(4.86), 18.93(4.68), 19.61(4.52), 20.71(4.29), 21.06(4.21), 22.19(4.00), 23.60(3.77), 24.20(3.68), 24.58(3.62), 25.10(3.55), 25.85(3.44), 26.75(3.33), 30.83(2.90), and 32.89(2.72). According to the invention, the I-type crystal of
lapatinib dibenzenesulfonate has better stability, and can be preferably used for clinic treatment.