Ink composition and container

[0079]Into a reaction vessel equipped with a stirrer, a reflux condenser, a dropping device, and a thermometer, 900 g of ion exchanged water and 3 g of sodium lauryl sulfate were put. The content was heated to 70° C. under stirring while the inside of the reaction vessel was purged with nitrogen. Then, 4 g of potassium persulfate as a polymerization initiator was added thereto and dissolved while the internal temperature was maintained to be 70° C.; and an emulsion preliminarily prepared by adding 20 g of acrylamide, 300 g of styrene, 640 g of butylacrylate, and 30 g of methacrylic acid to 450 g of ion exchanged water and 3 g of sodium lauryl sulfate under stirring was subsequently continuously dropped to the reaction solution over 4 hours. After the dropping, the resulting product was aged over three hours. The resulting aqueous emulsion was cooled to normal temperature, and then ion exchanged water and an aqueous solution of 5% sodium hydroxide were added thereto to adjust the solid

[0080]Into a reaction vessel equipped with a stirrer, a reflux condenser, a dropping device, and a thermometer, 900 g of ion exchanged water and 1 g of sodium lauryl sulfate were put. The content was heated to 70° C. under stirring while the inside of the reaction vessel was purged with nitrogen. Then, 4 g of potassium persulfate as a polymerization initiator was added thereto and dissolved while the internal temperature was maintained to be 70° C.; and an emulsion preliminarily prepared by adding 20 g of acrylamide, 365 g of styrene, 545 g of butylacrylate, and 30 g of methacrylic acid to 450 g of ion exchanged water and 3 g of sodium lauryl sulfate under stirring was subsequently continuously dropped to the reaction solution over 4 hours. After the dropping, the resulting product was aged over three hours. The resulting aqueous emulsion was cooled to normal temperature, and then ion exchanged water and an aqueous solution of sodium hydroxide were added thereto to adjust the solid con

[0081]Into a reaction vessel equipped with a stirrer, a reflux condenser, a dropping device, and a thermometer, 900 g of ion exchanged water and 1 g of sodium lauryl sulfate were put. The content was heated to 70° C. under stirring while the inside of the reaction vessel was purged with nitrogen. Then, 4 g of potassium persulfate as a polymerization initiator was added thereto and dissolved while the internal temperature was maintained to be 70° C.; and an emulsion preliminarily prepared by adding 20 g of acrylamide, 615 g of styrene, 295 g of butylacrylate, and 30 g of methacrylic acid to 450 g of ion exchanged water and 3 g of sodium lauryl sulfate under stirring was subsequently continuously dropped to the reaction solution over 4 hours. After the dropping, the resulting product was aged over three hours. The resulting aqueous emulsion was cooled to normal temperature, and then ion exchanged water and an aqueous solution of sodium hydroxide were added thereto to adjust the solid con