"The consummation of marriage creates new roles for the parties concerned. Each role is a set of equitable, proportionate rights and obligations. The role of the husband evolves around the moral principle that it is his solemn duty to God to treat his wife with kindness, honor, and patience; to keep her honorably or free her from and to cause her no harm or grief. (Qur'an 2:229-232; 4:19)
The role of the wife is summarized in the verse that women have rights even as they have duties, according to what is equitable; but men have a degree over them (2:228). The degree is usually interpreted by Muslim scholars in conjunction with another passage which states, among other things, that men are trustees, guardians and protectors of women because God has made some of them excel others and because men expend of the means (Qur'an, 4:34). This degree may be likened to what sociologists call "instrumental leadership" or external authority in the household due to the division of labor and role differentiation. It does not, however mean any categorical discrimination or superiority of one sex to the other.1
The link below has even more detailed information on marital relations.