Ink and ink-jet recording method using the same

摘要

An ink containing water, a water-soluble organic solvent and a colorant, wherein the ink exhibits a ( gamma cosθ)<1/2> value of 4 to 6, and satisfies Formula (I): 0.3≤(( gamma ' cosθ')<1/2> / ( gamma cosθ)<1/2>)≤0.85, wherein gamma represents a surface tension (mN/m) of the ink upon initial exposure to atmospheric conditions,θrepresents an initial contact angle of the ink with respect to plain paper upon initial exposure to atmospheric conditions; and gamma ' represents a surface tension (mN/m) of the ink after standing for one hour at 40 DEG C and relative humidity of 2 percent, andθ' represents an initial contact angle of the ink with respect to plain paper after standing for one hour at 40 DEG C and relative humidity of 2 percent.