Silicone Foam Sheet Open-Cell Structure Bubble Removability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing silicone foam sheets face challenges in forming thin sheets, have limited material choices, high closed-cell ratios leading to poor bubble removability and surface roughness, and decreased adhesiveness and sealability.
Innovation Solution
A silicone foam sheet with a thickness of less than 800 µm, formed by heat curing a silicone resin composition containing organopolysiloxanes, water, inorganic thickeners, surfactants, and a hydrosilylation reaction catalyst, with a high open-cell ratio and fine cell diameters, providing excellent bubble removability and adhesiveness, and a pressure-sensitive adhesive layer for enhanced sealability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If silicone foam is formed with high closed-cell ratio, then heat resistance and weatherability are improved, but bubble removability deteriorates and surface becomes rough
Solution Approach 1:
The patent applies porous materials by creating an open-cell foam structure where cells are interconnected through pores. This allows bubbles to escape through the porous network while maintaining the foam's structural integrity and heat resistance properties. The open-cell structure with 80-100% open-cell ratio provides pathways for bubble removal unlike conventional closed-cell structures.
Solution Approach 2:
The patent changes the fundamental parameter of cell structure from closed-cell to open-cell configuration. This parameter change transforms the foam's behavior regarding bubble trapped, allowing bubbles to escape through the open cell walls while maintaining other desirable properties like heat resistance and mechanical strength.
2Quantity of substance
If silicone foam sheet thickness is reduced, then weight and material usage are improved, but manufacturing difficulty increases
Solution Approach 1:
The patent changes the cell structure parameter from closed-cell to open-cell configuration, which fundamentally alters the foam's manufacturability. The open-cell structure allows for better control during foaming processes, enabling production of thin sheets without excessive difficulty while reducing material usage. The interconnected pore structure provides structural support even at reduced thickness.
Solution Approach 2:
By utilizing porous open-cell materials, the patent achieves thin sheet construction with adequate structural integrity. The porous network provides mechanical support distributed throughout the thin structure, making thin sheets manufacturable without requiring excessive thickness for structural reasons.
3Speed
If UV-curable silicone resin is used, then curing speed is improved, but material selection range narrows and cost increases
Solution Approach 1:
The patent substitutes the UV-curing mechanism with a thermal curing mechanism. Instead of using photopolymerization initiated by UV light, the invention employs heat-induced curing of silicone resin, which broadens material compatibility and reduces cost while still achieving practical curing speeds through thermal processing.
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 silicone foam sheet maintains stable modulus of elasticity across temperature regions, suppresses compression set, and ensures excellent adhesiveness and sealability even at reduced thickness, making it suitable for various applications.
Implementation Method 1
a hydrosilylation reaction catalyst
Implementation Method 2
containing (A) 100 parts by mass of an organopolysiloxane having at least two alkenyl groups in a molecule thereof; (B) an organopolysiloxane having at least two silicon atom-bonded hydrogen atoms in a molecule thereof
Implementation Method 3
0.1 part by mass to 15 parts by mass of surfactants including (D-1) a nonionic surfactant having an HLB value of 3 or more and (D-2) a nonionic surfactant having an HLB value of less than 3
Implementation Method 4
the sheet is formed by heat curing of a silicone resin composition
Data Source
AI summary
Provided is a silicone foam sheet that can express excellent bubble removability, that has satisfactory adhesiveness with an adherend, that has satisfactory sealability, that can maintain the expression of these effects even when its thickness is reduced, that can preferably express a stable modulus of elasticity over a region from a low-temperature region to a high-temperature region, and that can suppress both of its compression set in the low-temperature region and its compression set in the high-temperature region to low levels. Also provided is a silicone foam sheet composite including such silicone foam sheet. Also provided is a method of producing such silicone foam sheet. The silicone foam sheet of the present invention is a silicone foam sheet having a thickness of from 10 µm to 3,000 µm, wherein the silicone foam sheet has an open-cell structure, wherein an open-cell ratio of the silicone foam sheet is 90% or more, wherein an average cell diameter of the silicone foam sheet is from 1 µm to 50 µm, and wherein 90% or more of all cells in the silicone foam sheet each have a cell diameter of 80 µm or less.