Lithographic Printing Plate Precursor with Polyalkylene Oxide Binder
Solution Overview
Problem
Lithographic printing plate precursors face challenges in achieving high printing durability, excellent developing properties, and minimizing on-press development scum, despite advancements in binders and development methods.
Innovation Solution
A lithographic printing plate precursor is developed using a urethane resin with a polyalkylene oxide chain in its side chain, combined with an infrared absorbing agent, radical polymerizable compounds, and polymer fine particles, which enhances hydrophilicity and flexibility, allowing for improved on-press development and reduced scum.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional binders are used in lithographic printing plate precursors, then manufacturing simplicity is maintained, but printing durability and developing properties are insufficient
Solution Approach 1:
The patent uses a composite binder system comprising a polyalkylene oxide chain-containing polymer as the main binder combined with a specific photopolymerization initiator and infrared absorbing agent. This composite material approach achieves high printing durability and excellent developing properties by synergistically combining multiple functional components, resolving the contradiction between reliability improvement and structural complexity.
Solution Approach 2:
The patent modifies the binder's chemical structure by incorporating polyalkylene oxide chains with specific molecular weights and compositions. By changing the physical and chemical parameters of the binder (molecular weight, chain structure, composition ratios), the patent achieves improved printing durability and developing properties while maintaining a manageable structural complexity through systematic parameter optimization.
2Productivity
If high alkaline developers are used for development processing, then developing speed is improved, but environmental pollution from waste liquid increases
Solution Approach 1:
The patent changes the chemical parameters of the development system by using near-neutral pH finisher or gum solution instead of high alkaline developers. The specially designed binder with polyalkylene oxide chains enables effective development at neutral pH, achieving both environmental friendliness and adequate developing speed through parameter modification rather than extreme conditions.
Solution Approach 2:
The patent employs conventional, easily available finisher or gum solution materials that are environmentally benign and can be disposed of without severe pollution concerns. By designing the photosensitive layer to be removable by these mild agents, the patent replaces harsh, polluting developers with cheaper, environmentally friendly alternatives that achieve the same functional purpose.
3Ease of operation
If on-press development is implemented to simplify plate making, then operational complexity is reduced, but scum generation during printing increases
Solution Approach 1:
The patent modifies the chemical composition parameters of the photosensitive layer by incorporating polyalkylene oxide chain-containing polymers with specific hydrophilic-lipophilic balance. This parameter change enables the unexposed area to be effectively removed by near-neutral pH solutions during on-press development, reducing scum generation while maintaining operational simplicity.
Solution Approach 2:
The patent uses a composite formulation in the photosensitive layer combining the polyalkylene oxide binder with specific photopolymerization initiators and infrared absorbing agents. This composite material design ensures that the unexposed area becomes sufficiently hydrophilic and removable during on-press development, preventing scum formation while maintaining the ease of operation benefits of simplified plate making processes.
4Ease of operation
If infrared laser exposure is used for CTP technology, then workability in bright rooms is improved, but image-forming precision may be compromised
Solution Approach 1:
The patent changes the absorption characteristics of the photosensitive layer by incorporating specific infrared absorbing agents that match the infrared laser wavelength. Simultaneously, the polyalkylene oxide binder composition is optimized to ensure adequate photopolymerization response. This parameter coordination enables effective image formation with infrared laser while maintaining the workability advantage of bright room operation.
Solution Approach 2:
The patent employs a composite photosensitive layer formulation combining infrared absorbing agents, photopolymerization initiators, and polyalkylene oxide chain-containing polymers. This composite material design ensures that the layer responds effectively to infrared laser exposure with sufficient precision for high-quality printing, while allowing operation in bright rooms due to the infrared wavelength's insensitivity to visible light conditions.
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 provides a lithographic printing plate precursor with high printing durability, excellent developing properties, and reduced on-press development scum, outperforming previous binder technologies by improving the polymer tangle strength and ink adhesion.
Implementation Method 1
an infrared absorbing agent
Implementation Method 2
a radical polymerization initiator
Implementation Method 3
a radical polymerizable compound
Data Source
AI summary
A lithographic printing plate precursor includes a support, and an image-recording layer, the image-recording layer contains a urethane resin having a polyalkylene oxide chain represented by the formula (1) as defined herein in a side chain, an infrared absorbing agent, a radical polymerizable compound and a radical polymerization initiator, and an unexposed area of the image-recording layer is capable of being removed with at least one of dampening water and ink.