A silver halide emulsion, which is chemically sensitized by a compound of
formula (1): wherein Ch represents a sulfur, selenium, or tellurium
atom; X.sup.1 represents NR.sup.1 or N.sup.+(R.sup.2)R.sup.3Y.sup.-;
R.sup.1 represents a hydrogen atom or a substituent; R.sup.2 and R.sup.3
each represent an alkyl group or another substituent; Y.sup.- represents
an anionic ion; X.sup.2 represents OR.sup.4, N(R.sup.5)R.sup.6, or
another substituent; R.sup.4 to R.sup.6 each represent a hydrogen atom or
a substituent; and E is a group selected from groups represented by
formula (2) to (5): wherein, in formulas (2) to (5), Z represents a
hydrogen atom or a substituent; A.sup.1 and A.sup.2 each represent an
oxygen atom, etc.; and R.sup.10 to R.sup.16 each represent a hydrogen
atom or a substituent; W represents a substituent; n is an integer from 0
to 4; L represents a divalent linking group; and EWG represents an
electron withdrawing group.