The present invention aims to provide an ink ejection stabilizer that can impart high ejection stability, for example, to an ink such as an ink-jet printing ink. The present invention relates to an ink ejection stabilizer including a polymer (A) that has, in a Kratky plot of a scattering profile determined by a small-angle X-ray scattering method using synchrotron radiation, at least one local minimum in the range where a scattering vector q is 0 nm.sup.1 to 2 nm.sup.1. An aqueous solution of the polymer (A) (polymer (A) concentration: 20 mass %) has a parallel light transmittance of 85% or more.

The present invention provides a novel pretreating agent to improve the effect of ink-jet printing on polyester fabric and its application, and this invention belongs to the field of digital ink-jet printing. Stirring the dispersing agent, which includes many procedures of wetting agent and deionized water in a stirrer, adding nano-porous oxide dispersoid. Furthermore, keep stirring for 30 min and put the mixture in a sand mill to grinded for 2 h, then nano-porous oxide dispersoid is eventually got. The nano-porous oxide dispersoid work as pretreating agent, which used in the polyester fabric, is treated like pretreating agent during the padding process. By applying this technique into double-sided permeation ink-jet printing and direct-injection ink-jet printing, its pattern's definition, color depth and color saturation could be remarkable enhanced. This method has many advantages such as the craft is easy to handle as well as the operation is simplified, it is also suitable for batch production of the polyester fabric.

The present invention provides a novel pretreating agent to improve the effect of ink-jet printing on polyester fabric and its application, and this invention belongs to the field of digital ink-jet printing. Stirring the dispersing agent, which includes many procedures of wetting agent and deionized water in a stirrer, adding nano-porous oxide dispersoid. Furthermore, keep stirring for 30 min and put the mixture in a sand mill to grinded for 2 h, then nano-porous oxide dispersoid is eventually got. The nano-porous oxide dispersoid work as pretreating agent, which used in the polyester fabric, is treated like pretreating agent during the padding process. By applying this technique into double-sided permeation ink-jet printing and direct-injection ink-jet printing, its pattern's definition, colour depth and colour saturation could be remarkable enhanced. This method has many advantages such as the craft is easy to handle as well as the operation is simplified, it is also suitable for batch production of the polyester fabric.