Patent ID: 7866806

Claim:
A method comprising: a step of applying to a recording medium a liquid consisting of a first liquid composition and a second liquid composition, each of the liquid compositions comprising: a functional substance; an amphiphilic block copolymer; and a liquid medium, with a pH and a pKa of an organic acid group or a salt of the organic acid group of the copolymer of the first liquid composition being different than a pH and a pKa of an organic acid group or a salt of the organic acid group of the copolymer of the second liquid composition, wherein (i) the first liquid composition is greater than the second liquid composition in pH of the liquid compositions, (ii) the first liquid composition is greater than the second liquid composition in pKa of the organic acid group or the salt of the organic acid group of the copolymers, (iii) the organic acid of the copolymer of the second liquid composition is a sulfonic acid, and (iv) an increase in viscosity of the first liquid composition is caused by a decrease in pH of the first liquid composition on contact with the second liquid composition, and wherein the copolymer of the second liquid composition has a repeating unit structure represented by the following formula: where in OR 50 is represented by any formula selected from the group consisting of the following: OCH 2 CH 2 OPhSO 3 H OCH 2 CH 2 OPhSO 3 − M OCH 2 CH 2 PhSO 3 H OCH 2 CH 2 PhSO 3 − M OCH 2 CH 2 OPhPhSO 3 − M OCH 2 CH 2 ONpSO 3 − M OCH 2 CH 2 CH 2 OPhSO 3 H OCH 2 CH 2 Ph(CH 3 )SO 3 − M OCH 2 CH 2 CH 2 CH 2 PhSO 3 −M OCH 2 CH 2 CH 2 OPhSO 3 − M OCH 2 CH(CH 3 )OPhSO 3 − M OCH 2 CH(CH 2 H 5 )OPhSO 3 H OCH 2 CH(C 3 H 7 )OPhSO 3 − M O(CH 2 CH 2 O) 2 PhSO 3 H OCH 2 CH 2 O(CH 2 CH 2 CH 2 O) 2 PhSO 3 H OCH 2 CH 2 PyPhSO 3 − M OCH 2 CH 2 OPyPhSO 3 − M O(CH 2 CH 2 O) 2 (CH 2 ) 2 PhSO 3 H O(CH 2 CH 2 O) 3 (CH 2 ) 2 PhSO 3 − M O(CH 2 CH 2 O) 20 PhSO 3 H O(CH 2 CH 2 O) 2 (CH 2 ) 6 OphSO 3 − M O(CH2CH 2 O) 6 (CH 2 ) 8 )OphSO 3 H O(CH 2 CH 2 O) 10 (CH 2 ) 10 OphSO 3 − M O(CH 2 CH 2 O) 2 (CH 2 ) 20 OphSO 3 H OCH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 O(CH 2 ) 2 OPhSO − M OCH 2 CH 2 CH 2 CH 2 O(CH 2 ) 4 OPhSO 3 H OCH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 O(CH 2 ) 5 OphSO 3 − M wherein M represents a monovalent or multivalent cation, Ph represents 1,4-phenylene or 1,3-phenylene, Py represents 2,5-pyrimidyl, and Np represents 2,6-napthylene, 1,4-napthylene, or 1,5-napthylene.