Elastic artificial leather and production method therefor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing elastically stretchable artificial leathers fail to effectively enhance stretchability and mechanical properties in the machine direction while maintaining surface quality and wear resistance, particularly due to issues with adhesive use, substrate shrinkage, and uneven thickness.
Innovation Solution
A production method involving the creation of a microfiberizable fiber web, entanglement to form a nonwoven fabric, conversion to microfine fibers, and subsequent processing with an elastomer sheet stretched in the machine direction, followed by mechanical shrinking and heat-treating to form a wave-like structure, which enhances elasticity and resistance to further stretching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If an elastomer sheet is adhesively bonded to an entangled fiber body and then forced to shrink, then elasticity is improved, but productivity decreases due to adhesive application and removal steps
Solution Approach 1:
The invention removes the adhesive from the production process entirely. Instead of using adhesive to bond the elastomer sheet to the entangled fiber body, the method directly forms the artificial leather structure through mechanical entanglement and heat treatment, eliminating the need for adhesive application and removal steps that reduce productivity.
Solution Approach 2:
The entangled fiber body itself serves as the substrate that provides both structural support and elasticity. The microfine fibers (0.9 dtex or less) are entangled to form a self-supporting network that eliminates the need for separate adhesive layers, allowing the material to bond and shrink through its own structural properties rather than requiring external adhesive agents.
2Strength
If the substrate for artificial leather is forced to shrink by elastomer sheet relaxation, then elasticity is improved, but the substrate curls toward the elastomer sheet side making process passing properties poor
Solution Approach 1:
Instead of forcing the substrate to shrink by relaxing the elastomer sheet from behind (which causes curling), the invention applies shrinkage force directly to the entangled fiber body itself through heat treatment. The substrate is heated to a temperature where it naturally shrinks and stabilizes without curling, then cooled to lock in the shrunk state, reversing the conventional approach of using elastomer relaxation to drive shrinkage.
3Strength
If the substrate is forced to shrink only by elastomer sheet shrinking force, then elasticity is improved, but high-density substrates cannot achieve high shrinkage
Solution Approach 1:
The invention changes the physical parameter of temperature to enable shrinkage. By heating the entangled fiber body to a specific temperature range (above the glass transition temperature of the fibers but below decomposition temperature), the material becomes more pliable and capable of achieving high shrinkage rates even in high-density substrates. The heat treatment allows the tightly entangled microfine fibers to rearrange and contract uniformly, achieving shrinkage rates of 20% or more that cannot be obtained through mechanical force alone.
4Strength
If stretch is applied in the machine direction under heating to improve transverse stretchability, then transverse elasticity is improved, but machine direction stretchability decreases and surface uniformity deteriorates
Solution Approach 1:
The invention applies different treatments to different directions of the entangled fiber body. The entanglement structure is created with preferred orientation in the transverse direction, and heat treatment is applied selectively to enhance shrinkage in the transverse direction while maintaining machine direction stability. This directional differentiation allows the material to achieve high transverse elasticity (40% or more) while maintaining surface uniformity and machine direction stretchability, avoiding the suede-finished appearance and wear resistance problems caused by uniform heating in both directions.
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 method produces artificial leather with improved elasticity, resistance to further stretching, and enhanced mechanical properties in the machine direction, maintaining surface quality and wear resistance, suitable for various applications including clothing and interior decorations.
Implementation Method 1
the artificial leather is allowed to shrink in the machine direction simultaneously with allowing the elastomer sheet to shrink in the machine direction by relaxing elongation of the elastomer sheet
Implementation Method 2
the artificial leather is heat-treated in shrunk state; and then the artificial leather is peeled off from the elastomer sheet
Data Source
AI summary
Disclosed herein is a method for producing an elastically stretchable artificial leather, which includes the steps of forming microfiberizable fibers into a web, entangling the obtained web to produce an entangled nonwoven fabric, converting the microfiberizable fibers in the nonwoven fabric to microfine fibers thereby producing a substrate for artificial leather, producing an artificial leather from the obtained substrate for artificial leather, bringing the obtained artificial leather into close contact with an elastomer sheet stretched in a machine direction by 5 to 40%, shrinking the artificial leather in the machine direction simultaneously with the elastomer sheet by relaxing elongation of the elastomer sheet to obtain an artificial leather in shrunk state, heat treating the artificial leather in shrunk state, and then peeling the heat treated artificial leather off from the elastomer sheet.