Polyamide Reflector for LED Heat Resistance and Fluidity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional polyamide reflectors for light-emitting devices lack sufficient fluidity, resistance to thermal and optical color changes, and durability, leading to reduced LED life and luminance.

Innovation Solution

A reflector composed of a polyamide polymerized from at least 50 mol% alicyclic dicarboxylic acid and 50 mol% diamine with a branched main chain, combined with titanium oxide and stabilizers, providing enhanced heat resistance, fluidity, and optical stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If conventional polyamide comprising terephthalic acid units is used, then soldering heat resistance is improved, but fluidity and resistance against thermal and optical color change are insufficient

Engineering Contradiction:
Improvesoldering heat resistanceVSAvoidfluidity
Core Design Contradiction:
TemperatureVSEase of manufacture

Solution Approach 1:

The invention changes the chemical composition parameters of the polyamide by using alicyclic dicarboxylic acid (50-100 mol%) instead of conventional terephthalic acid, and branched aliphatic diamine (50-100 mol%) instead of linear diamines. This parameter change achieves both high heat resistance (melting point 270-350°C) and improved fluidity during molding, resolving the contradiction between heat resistance and manufacturability.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite polyamide material combining alicyclic dicarboxylic acid units with branched aliphatic diamine units. This composite structure provides synergistic effects where the alicyclic component contributes to heat resistance while the branched aliphatic component enhances fluidity and moldability, simultaneously satisfying both requirements.

Inventive Principle:
Principle #40Composite materials

2Temperature

If conventional polyamide comprising terephthalic acid units is used, then soldering heat resistance is improved, but resistance against thermal and optical color change is insufficient

Engineering Contradiction:
Improvesoldering heat resistanceVSAvoidresistance against thermal and optical color change
Core Design Contradiction:
TemperatureVSStability of the object's composition

Solution Approach 1:

The invention changes the chemical structure parameters by incorporating alicyclic dicarboxylic acid units which provide inherent thermal and optical stability. The cyclic structure resists degradation from heat and UV exposure, preventing color change while maintaining the required heat resistance for soldering processes.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention avoids using expensive stabilizers and additives by selecting base monomers (alicyclic dicarboxylic acid and branched aliphatic diamine) that inherently provide long-term stability against thermal and optical degradation, eliminating the need for additional protective components.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Ease of manufacture

If reflector material deteriorates, then LED assembly can be manufactured, but LED life and luminance are reduced

Engineering Contradiction:
Improvemanufacturability of LED assemblyVSAvoidLED life
Core Design Contradiction:
Ease of manufactureVSDuration of action of moving object

Solution Approach 1:

The invention provides beforehand cushioning against deterioration by selecting polyamide monomers with inherent stability against thermal, mechanical, and optical degradation. The alicyclic structure and branched aliphatic chains are pre-configured to resist common failure modes in LED operating environments, preventing deterioration before it occurs and ensuring long LED life while maintaining manufacturability.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Data Source

PatentEP2477243B1Reflector for light-emitting device, and light-emitting device
Publication Date: 2016.01.06 ASAHI KASEI KOGYO KABUSHIKI KAISHA
  • EP2477243B1 patent drawingFigure 1
  • EP2477243B1 patent drawingFigure 2
  • EP2477243B1 patent drawingFigure 3(a)~3(d)

AI summary

The present invention relates to a reflector for a light-emitting device consisting of (A) an polyamide composition comprising a polyamide polymerized from (a) a dicarboxylic acid comprising at least 50 mol% of an alicyclic dicarboxylic acid and (b) a diamine comprising at least 50 mol% of a diamine with a branched main chain.