Inkjet Decorative Laminate Coating for Adhesion and Pattern Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The manufacturing of decorative laminates using inkjet technology faces challenges with adhesion issues between acrylate ink layers and melamine resin, particularly at high ink coverages, and dimensional instability of decor paper during thermosetting resin impregnation, which affects the alignment of embossed wood grain patterns.
Innovation Solution
A method involving the use of aqueous pigmented inkjet inks with an inorganic pigment and polymeric binder in a specific ratio, applied to an ink acceptance layer on fully impregnated base paper, allowing for improved adhesion and dimensional stability, enabling precise alignment of wood grain patterns and simplifying the manufacturing process by eliminating the need for intermediate decor printers and warehouses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If acrylate inkjet inks are used for printing decorative patterns, then excellent image quality is achieved, but adhesion problems occur between the ink layer and melamine resin protective layer
Solution Approach 1:
A primer layer is introduced as an intermediary between the acrylate inkjet printed decorative pattern and the melamine resin protective layer. This primer layer serves as a bonding interface that ensures proper adhesion of the protective layer to the printed pattern, eliminating the adhesion problems that would otherwise occur between the non-porous acrylate ink layer and the melamine resin.
Solution Approach 2:
The coating structure is segmented into distinct functional layers: the acrylate inkjet printed decorative pattern layer, a primer layer in between, and the melamine resin protective layer. This segmentation allows each layer to perform its specific function optimally - the ink layer provides the decorative pattern, the primer provides adhesion, and the protective layer provides durability.
2Ease of manufacture
If decor paper is impregnated with thermosetting resin after inkjet printing, then dimensional instability occurs affecting alignment of embossed wood grain patterns
Solution Approach 1:
The inkjet printing of the decorative pattern is performed preliminarily before the impregnation with thermosetting resin. This preliminary action allows the decorative pattern to be established on the paper substrate before the resin impregnation and subsequent embossing processes, ensuring that the pattern alignment is maintained throughout manufacturing.
Solution Approach 2:
A primer layer is applied as an intermediary coating between the inkjet printed decorative pattern and the thermosetting resin impregnation. This primer layer acts as a stable interface that prevents dimensional instability from affecting the alignment of the decorative pattern during the embossing process, ensuring precise alignment between the printed pattern and the embossed wood grain.
3Productivity
If gravure printing is used for manufacturing decorative paper rolls, then production efficiency is maintained, but flexibility for variable data printing and short production runs is limited
Solution Approach 1:
The mechanical gravure printing system is replaced with an inkjet printing system. This substitution eliminates the need for physical printing plates and allows for digital, variable data printing. The inkjet system maintains production efficiency while providing the flexibility to quickly change decorative patterns and produce short runs without the constraints of gravure printing setup.
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 ensures excellent image quality and adhesion, reduces storage needs, minimizes paper loss, and allows for rapid design changes and cost-efficient short print runs, enhancing product variety and adaptability to market trends.
Implementation Method 1
jetting ink droplets having a volume of up to 30 pL of one or more aqueous pigmented inkjet inks onto the dried ink acceptance layer
Implementation Method 2
The ink acceptance layer contains an inorganic pigment P and a polymeric binder B in a weight ratio P/B larger than 1.5, wherein the decorative layer includes the paper substrate impregnated by a thermosetting resin, an ink acceptance layer containing an inorganic pigment P and a polymeric binder B having a weight ratio of inorganic pigment to polymeric binder (P/B ratio) of larger than 1.5
Implementation Method 3
The cause of these adhesion problems is that the water vapour produced during the polycondensation of the melamine cannot penetrate through the polymerized acrylate ink layer
Implementation Method 4
the water vapour produced during the polycondensation of the melamine
Implementation Method 5
curing the resin mixture (5, 21) by means of a heated press (7)
Data Source
Figure 1~4
AI summary
Manufacturing method of decorative laminates including the steps of: a) printing an ink acceptance layer by jetting droplets having a volume of 1 to 200 nL onto a paper substrate; b) forming a decorative layer by jetting ink droplets having a volume of up to 30 pL of one or more aqueous pigmented inkjet inks onto the dried ink acceptance layer; and c) heat pressing the decorative layer into a decorative laminate; wherein the ink acceptance layer contains an inorganic pigment P and a polymeric binder B in a weight ratio P/B larger than 1.5.