TECHNOLOGY FOCUS - IMAGING AND COMMUNICATION - Preferred Method: The formation of an image is performed using a single kind of an ink composition. The formation of an image is performed using at least two kinds of an ink composition. The attachment of the pretreatment liquid onto plain paper is performed by an inkjet printing system of a multi-drop type. Preferred Composition: The ink composition is selected from black ink, cyan ink, magenta ink and yellow ink. The pretreatment liquid comprises (wt.%) water (40-90, preferably 50-80); fluorescent brightener (0.2-10) and metal salt (2-30). The pretreatment liquid further comprises a surfactant; and a wetting agent ( not greater than 10 wt.%). The pretreatment liquid has a viscosity not greater than 20 mPas at 25 degrees C.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The metal salt contains a metal ion selected from Na+, K+, Ca2+, Mg2+, Cu2+, Ni2+, Ba2+, Al3+ and Fe3+. The metal ion is divalent or polyvalent. The metal salt contains an anion selected from Cl-, NO3-, I-, CH3COO-, C2H5COO- and CH3C(OH)HCOO-.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The fluorescent brightener is selected from stilbene based compound, diaminostilbene based compound, coumarin derivative, pyrazoline derivative, pyrene derivative and thiazole derivative.    TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The pretreatment liquid further comprises a water-soluble polymer selected from methyl cellulose, ethyl cellulose, polyvinyl alcohol, polyvinylpyrrolidone and polysaccharide. Preferred Components: The wetting agent is glycerin. EXAMPLE - A pretreatment liquid (L1) comprising (wt.%) water (48.9), 3-methoxy-3-methyl-1-butanol (30), glycerin (10), calcium chloride (10), KAYAPHOR FKY (RTM: optical brightener) (1) and PROXEL XL-2 (RTM: aqueous propylene glycol solution of 1,2-benzothiazolin-3-one) (0.1) was prepared. The pretreatment liquid (L1) when used for inkjet recording, the image obtained was clear and no blur was generated.