White Inkjet Ink Formulation for UV LED Curing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Formulating a white inkjet ink that achieves a desirable balance of properties such as cure, blocking, adhesion, and flexibility when using a UV LED source as the actinic radiation source is challenging due to the narrow wavelength output and reduced energy of LEDs compared to other UV sources, particularly for inks requiring high pigment load for opacity.
Innovation Solution
The white inkjet ink comprises tricyclodecane dimethanol diacrylate, at least one of a difunctional urethane (meth)acrylate oligomer, (2-methyl-2-ethyl-1,3-dioxolane-4-yl)methyl acrylate, and a polyethylene glycol diacrylate, which together provide improved adhesion, flexibility, and blocking performance even under UV LED curing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If UV LED source is used to cure the ink, then energy efficiency and maintenance intervals are improved, but the wavelength output is narrow and energy output is reduced, making it difficult to achieve required cure and film properties
Solution Approach 1:
The patent changes the chemical parameters of the ink formulation by incorporating specific monomers (tricyclodecane dimethanol diacrylate, difunctional urethane (meth)acrylate oligomers, and monofunctional monomers) that are optimized for UV LED curing. This allows the ink to achieve proper cure and film properties despite the reduced energy output of LED sources.
Solution Approach 2:
The patent uses a composite monomer system combining multiple types of (meth)acrylate monomers with different functionalities. This composite approach allows the ink to respond effectively to the narrow wavelength output of UV LEDs while maintaining comprehensive film properties including cure, blocking, adhesion, and flexibility.
2Ease of manufacture
If UV LED source is used to cure the ink, then cost and maintenance are improved, but adhesion and flexibility properties deteriorate
Solution Approach 1:
The patent modifies the chemical composition parameters by including specific ratios of difunctional and monofunctional (meth)acrylate monomers. The difunctional monomers provide crosslinking for adhesion, while monofunctional monomers contribute to flexibility, achieving both properties simultaneously under UV LED curing.
Solution Approach 2:
The patent uses photoinitiators as intermediaries that absorb UV LED radiation and transfer energy to the (meth)acrylate monomers, enabling effective curing that develops both adhesion and flexibility properties despite the limited wavelength output of LED sources.
3Ease of operation
If UV LED source is used to cure the ink, then operational characteristics are improved, but blocking properties worsen
Solution Approach 1:
The patent adjusts the formulation parameters by incorporating tricyclodecane dimethanol diacrylate and difunctional (meth)acrylate monomers that promote thorough curing. This ensures blocking properties are maintained even with the reduced energy output of UV LED sources.
Solution Approach 2:
The patent employs a composite monomer system where difunctional monomers provide crosslinking density for blocking resistance, while the overall formulation is optimized for UV LED wavelengths, achieving both operational efficiency and reliable blocking properties.
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 formulation ensures a desirable balance of properties including cure, blocking, adhesion, and flexibility for white inkjet ink when cured with a UV LED source, overcoming the limitations of traditional UV sources in achieving these characteristics.
Implementation Method 1
which polymerise when cured. By 'radiation-curable' is meant a material that polymerises and/or crosslinks upon irradiation, for example, when exposed to actinic radiation, in the presence of a photoinitiator
Data Source
AI summary
The present invention provides a white inkjet ink comprising: tricyclodecane dimethanol diacrylate; at least one of a difunctional urethane (meth)acrylate oligomer, (2-methyl-2-ethyl-1,3-dioxolane-4-yl)methyl acrylate and a polyethylene glycol diacrylate; a white pigment; and a monofunctional monomer, other than (2-methyl-2-ethyl-1,3-dioxolane-4-yl)methyl acrylate. The present invention further provides a method of inkjet printing comprising inkjet printing the inkjet ink of the present invention onto a substrate and curing the inkjet ink by exposing the inkjet ink to a curing source, preferably wherein the curing source is a UV LED light.