Inkjet Print Head and UV Curing Arrangement for Droplet Leveling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inkjet printers using ultraviolet curable ink face issues with UV ink droplets mixing and bleeding, leading to poor print quality due to uneven curing, resulting in raised beading shapes and mixed colors.
Innovation Solution
An inkjet printer design with a print head projecting towards the upstream of the ultraviolet light irradiation means, allowing ink droplets to spread and level before curing, combined with adjustable UV LED intensity and arrangement to ensure complete curing without immediate irradiation, preventing bleeding and achieving high-quality prints.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If ultraviolet light irradiation means is positioned directly above the print head, then ink droplets are cured immediately after ejection, but the ink droplets form raised beading shapes and do not spread evenly
Solution Approach 1:
The ultraviolet light irradiation means is positioned laterally adjacent to the print head rather than directly above it, changing the spatial arrangement from a vertical one-dimensional alignment to a lateral two-dimensional configuration. This allows ink droplets to spread in the longitudinal direction before curing, preventing beading while maintaining curing effectiveness.
Solution Approach 2:
The ink droplets are allowed to spread and level on the print medium before the ultraviolet light irradiation means cures them. This preliminary spreading action occurs in the lateral direction adjacent to the print head, ensuring uniform distribution before the curing process begins, thereby eliminating raised beading shapes.
2Productivity
If ultraviolet light irradiation is applied immediately after ink ejection, then curing efficiency is improved, but ink droplets mix and bleed causing poor print quality
Solution Approach 1:
The ultraviolet light irradiation means is positioned to irradiate only the lateral edges of the ink droplets immediately after ejection, while the central portion remains uncured and allows for proper spreading. This localized irradiation approach prevents premature complete curing that would cause bleeding, while still providing initial stabilization at the droplet perimeters.
Solution Approach 2:
The curing process is shifted from a vertical top-down approach to a lateral side-approach. The ultraviolet light irradiation means is arranged beside the print head in the lateral direction, allowing ink droplets to spread forward in the printing direction before being cured from the sides, thus preventing mixing and bleeding.
3Shape
If the print head and ultraviolet light irradiation means are arranged side by side, then ink droplets can spread before curing, but the device complexity increases
Solution Approach 1:
The ultraviolet light irradiation means is integrated with the print head assembly as a unified module. The irradiation means is positioned adjacent to the print head nozzles within the same carriage structure, combining the printing and curing functions into a single integrated unit that reciprocates together, thereby simplifying the overall device architecture despite the lateral arrangement.
Solution Approach 2:
The carriage structure serves multiple functions: it holds both the print head for ink ejection and the ultraviolet light irradiation means for curing, and provides the reciprocating motion for both operations. This multi-functional design reduces the need for separate mounting mechanisms and simplifies the overall system complexity.
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 printer ensures UV ink droplets are evenly spread and cured, preventing beading and bleeding, resulting in high-quality prints with improved visual appearance and print quality.
Implementation Method 1
an inkjet printer in which ink is ejected from a print head onto a print medium... ejecting ultraviolet curable ink (hereinafter, referred to as UV ink) having a property that it is cured when irradiated with ultraviolet light
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An inkjet printer (10) comprises: a platen (12a), a print head (22) for ejecting ink droplets, a right ultraviolet light irradiation device (23R) and a left ultraviolet light irradiation device (23L) for curing the ink droplets, and a carriage (21) on which the print head (22), the right ultraviolet light irradiation device (23R), and the left ultraviolet light irradiation device (23L) are mounted to face the platen (12a) and which is operated to reciprocate in the right-left direction relative to a print sheet (1) and is moved forward relative to the print sheet (1). On the carriage (21), the right ultraviolet light irradiation device (23R) and the left ultraviolet light irradiation device (23L) are arranged on both sides of the print head (22) in the right-left direction, and the print head (22) is arranged to project rearward relative to the right ultraviolet light irradiation device (23R) and the left ultraviolet light irradiation device (23L) by a predetermined length.