Textile printing is the process of printing a pattern or other design onto fabric. Although screen printing currently dominates the global textile printing market, in recent years inkjet printing has fast been making inroads as a revolutionary method of dying, mainly for apparel makers in areas such as fast fashion.
Inkjet textile printing does not require the plates needed for screen printing, and thus has the following advantages:
- 1) It is useful for the production of lots as small as a single garment.
- 2) It is useful for making a wide range of products in different colors and patterns.
- 3) It permits the use of numerous colors, thereby enabling outstanding reproduction of gradations.
- 4) It is excellent at reproducing fine lines, thereby enabling the printing of finely detailed patterns.
- 5) It is capable of production with rapid delivery times.
Inkjet textile printing may be useful for producing small lots, but demand for this method is now rising on the basis of its capacity to produce original designs, such as scarves for famous brands, with rapid delivery times, and there is an increasing need for ultra-fast devices capable of handling large lots.
Ultra-fast devices require a rapid fabric feed speed, making it difficult to maintain a consistent feed volume of fabric. If the fabric is not supplied at a consistent speed, the feed volume fluctuates, and this can cause the print density to become patchy. To prevent this requires technology that maintains its precision while minimizing factors that could adversely affect the feed.
The fabric feed unit uses the belt feed method. Fluctuations in load due to friction from the belt cleaning unit that removes residual ink from the belt, and the effect of the drier connected on the fabric output side, cause tiny variations in belt speed. Konica Minolta has developed a method of measuring the distances moved by the belt in real time and feeding this information back into the belt control system to achieve more accurate belt feed.
This technique of directly detecting the feed volume of the feed belt and correcting it to achieve the target feed volume is called “feed volume correction control.” As shown in the illustration, a linear sensor is installed that moves in conjunction with the belt feed and measures the actual distance moved by the belt with an accuracy of a few microns. The difference between the actual movement of the belt and the target movement is fed back into the rotation of the feed motor, enabling high-precision feed control.