Printing Apparatus Head Ejects Separate Liquids for Background and Image
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional image recording apparatuses experience color irregularities and banding when recording images on transparent media due to uneven ink ejection, leading to a drop in image quality, especially in areas with overlapping colors.
Innovation Solution
A printing apparatus with a head that separately ejects two types of liquid and an energy applying device to cure them, operating in two modes: one for forming a background and another for directly printing images, with the controller adjusting the ejection quantity of the second type of liquid to prevent spreading and enhance image quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If white ink is ejected for all pixels or non-basic-color pixels to make the image stand out, then the image visibility on transparent medium is improved, but color irregularities and banding occur due to reduced basic ink ejection quantity
Solution Approach 1:
The patent segments the ink ejection process into two independent types: first type of liquid (basic color ink) and second type of liquid (white ink). This allows separate control of ejection quantities for each ink type, enabling the system to maintain adequate basic color ink ejection while still providing white ink for image visibility on transparent media, thereby resolving the contradiction between image visibility and color uniformity
Solution Approach 2:
The patent introduces mode switching that changes the ejection parameters dynamically. In first mode, the head ejects only the first type of liquid with normal ejection quantity. In second mode, the head ejects both first and second types of liquids with adjusted ejection quantities. This parameter change allows optimization of both image visibility and color uniformity by selecting appropriate modes for different printing scenarios
2Quantity of substance
If the ejection quantity of basic inks is reduced in areas with large white ink ejection quantity, then uniform ink quantity is achieved, but color irregularities and banding occur
Solution Approach 1:
By segmenting the ink types into first type (basic color) and second type (white ink), the system can independently control ejection quantities for each type. This prevents the need to reduce basic ink ejection to compensate for white ink ejection, thereby maintaining both ink quantity uniformity and color consistency simultaneously
Solution Approach 2:
The patent allows the second type of liquid (white ink) to be ejected in excess in certain areas where image visibility is needed, without requiring reduction of the first type of liquid (basic color ink). This partial excessive action of white ink is compensated by maintaining normal or increased basic color ink ejection, ensuring overall color consistency while achieving the desired visual effect
3Manufacturing precision
If the head ejects both first type of liquid and second type of liquid, then image quality in overlapping color areas is improved, but the complexity of the ejection system increases
Solution Approach 1:
The head is designed with multi-functionality to eject both the first type of liquid and the second type of liquid using the same ejection mechanism. This universal design allows the system to handle multiple ink types without requiring separate ejection systems for each, thereby improving image quality in overlapping color areas while minimizing the increase in system complexity
Solution Approach 2:
The controller manages the dual ejection capability by changing operational parameters (mode selection) rather than requiring complex hardware changes. The system can switch between first mode (ejecting only first type of liquid) and second mode (ejecting both types) based on printing requirements, simplifying the control of a potentially complex multi-ink ejection system
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces color irregularities and banding by increasing the ejection quantity of the second type of liquid in the first mode, thereby suppressing a drop in image quality in areas with overlapping colors, while ensuring the second type of liquid does not spread easily over the background.
Implementation Method 1
The energy applying device is configured to cure the first type of liquid and the second type of liquid on the printing medium
Data Source
AI summary
In a printing apparatus, in a first mode a head ejects a first type of liquid onto a printing medium and an energy applying device applies energy to the first type of liquid to form a background, and subsequently the head ejects a second type of liquid onto the background and the energy applying device applies energy to the second type of liquid on the background so that an image is formed on the background. In a second mode the head ejects the second type of liquid onto the printing medium without forming a background, and the energy applying device applies energy to the second type of liquid. The controller performs setting a quantity of the second type of liquid to be used in the first mode, to be greater than a quantity of the second type of liquid to be used in the second mode.