1. Field of the Invention
The present invention relates to an ink jet output apparatus for performing recording operation by ejecting ink from nozzles onto a material to be recorded, and, more particularly to an ink jet output apparatus capable of controlling the viscosity and amount of the ink to be ejected on a material into optimum values respectively according to the type of the material to be recorded, thereby enabling to perform recording operation with constant recording quality without regard to the types of materials to be recorded.
2. Description of Related Art
In an ink jet output apparatus, generally, ink droplets are ejected from nozzles onto a material to be recorded such as a paper and the like, and is adhered to form dots which in total represent a desired figure, thereby recording various images, i.e., characters and marks on the material. The ink adhered on the material to be recorded tends to more or less spread and be blurred thereon. The degree of the ink spread has an influence on the density and resolving power of print characters and the like. The degree of the ink blur varies with types of materials to be recorded, ink viscosity, and an amount of an ink droplet.
Accordingly, the ink jet output apparatus, taking coated paper applied with a special coat to regulate ink absorbency as a standard for a material to be recorded, determines driving conditions for ejecting ink, i.e., ink temperature to perform an ink ejection at an optimum viscosity of ink and an optimum amount of an ink droplet, thereby enabling to provide high recording quality.
For example, there is provided an ink jet recording apparatus described in Japanese Patent Application laid-open No. 5-57904, from which U.S. Pat. No. 5,477,246 claims a part of priority, which controls ink temperature to change according to the types of the materials to be recorded. This apparatus has a purpose of performing a print operation on materials except for a coated paper, e.g., a copy sheet, an OHP sheet, and the like, and therefore utilizes the property of ink that the amount of an ink droplet is influenced by the temperature of the ink.
There is also proposed an ink jet printer described in Japanese Patent Application laid-open No. 6-226963, which controls the amount of an ink droplet to change according to a change in types of materials to be recorded.
In the ink jet output apparatus in the prior art, however, as a change in types of materials to be recorded, it only considers a difference in brands of coated papers, and a difference among copy sheet, regular paper, and at most OHP sheet in addition to coated sheet. These sheets only cause slightly blur. Therefore, when used is a material to be recorded such as cloth which easily causes blur than the above materials it results in performing the recording operation with low recording quality. It is conceivable to extremely reduce the amount of droplet can be supposed to prevent ink blur, but it results in unsatisfactory density because of a decrease in the amount of ink. Consequently, it is impossible to easily print desired images on handkerchiefs, T-shirts, and the like, instead of doing embroidery thereon.