Image Forming System Varnish Curing Discoloration Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image forming systems face challenges in preventing discoloration of toner images when varnish is applied and cured with ultraviolet radiation, particularly when black toner containing carbon black is used.
Innovation Solution
The system employs a controller to adjust the image formation process, replacing black toner with a combination of cyan, magenta, and yellow toners in areas where varnish overlaps with the black toner, thereby avoiding the use of carbon black and reducing heat generation during varnish curing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If black toner containing carbon black is used to form the toner image, then the toner image can be formed with good black color, but the toner image discolors when varnish is cured with ultraviolet radiation
Solution Approach 1:
The patent changes the chemical composition parameter of the toner by replacing carbon black with a combination of cyan, magenta, and yellow colorants. This substitution maintains the black color appearance while eliminating the carbon black component that causes heat generation and discoloration during UV curing, thus resolving the contradiction between black color quality and color stability
Solution Approach 2:
The patent uses a composite approach by combining multiple colorants (cyan, magenta, yellow) to achieve black color instead of using a single carbon black material. This composite colorant system produces the desired black appearance while avoiding the harmful thermal effects of carbon black under UV irradiation, thereby maintaining both color quality and stability
2Productivity
If ultraviolet radiation is used to cure the varnish, then the varnish can be efficiently solidified, but the carbon black in the toner generates heat and causes discoloration
Solution Approach 1:
The patent converts the harmful interaction between UV radiation and carbon black into a beneficial outcome by removing carbon black from the system. By replacing it with UV-stable colorants, the UV curing process becomes purely beneficial for varnish solidification without the harmful heat generation side effect, thus maintaining high productivity while eliminating the harmful factor
Solution Approach 2:
The patent changes the material composition parameter of the toner to eliminate carbon black, thereby removing the source of heat generation during UV curing. This allows the UV radiation to be used efficiently for varnish curing without generating harmful heat, resolving the contradiction between curing efficiency and harmful heat generation
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
This approach effectively suppresses discoloration of the toner image by minimizing heat generation due to the absence of carbon black, ensuring the quality and integrity of the toner image even after varnish application and curing.
Implementation Method 1
the varnish is cured by being irradiated with ultraviolet radiation
Implementation Method 2
an irradiation unit configured to irradiate the varnish on the recording material with light to cure the varnish on the recording material
Implementation Method 3
a first developing unit for developing an electrostatic latent image, formed on the first photosensitive member
Data Source
AI summary
An image forming system includes an image forming unit including a first photosensitive member, a first developing unit, a second photosensitive member, a second developing unit, a third photosensitive member, a third developing unit, a fourth photosensitive member, and a fourth developing unit; a varnish applying unit; an irradiation unit; and a controller configured to control image formation by the image forming unit to form a black image, on which the varnish is superimposed, with yellow toner, magenta toner, and cyan toner.