Laminated Glass Interlayer Composition for Color Stability and Void Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional interlayer films for laminated glass suffer from discoloration in the colored parts and void generation at the end parts, which affect the appearance and adhesive force of the glass, making it difficult to suppress both issues simultaneously.

Innovation Solution

An interlayer film with a colored part and a non-colored part, where the non-colored part contains a higher concentration of hindered amine light stabilizer than the colored part, and the light stabilizer is strategically located to prevent discoloration and void formation, ensuring the adhesive force and appearance of the laminated glass are maintained.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a light stabilizer is added to the colored part to prevent discoloration, then the discoloration resistance is improved, but the void generation at the end part increases

Engineering Contradiction:
Improvediscoloration resistanceVSAvoidvoid generation
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent applies local quality by creating distinct regions within the interlayer film with different light stabilizer concentrations. The colored part has a first light stabilizer concentration optimized for preventing discoloration, while the end part has a second light stabilizer concentration optimized for preventing void generation. This spatial differentiation of material properties resolves the contradiction by allowing each region to have the specific composition needed for its function.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent segments the interlayer film into functionally distinct regions: a colored part and an end part, each with different light stabilizer concentrations. This segmentation allows the film to simultaneously address both discoloration prevention in the colored region and void prevention in the end region, resolving the technical contradiction through functional分区.

Inventive Principle:
Principle #1Segmentation

2Reliability

If the light stabilizer concentration is increased throughout the interlayer film to prevent discoloration, then the discoloration resistance is improved, but the adhesive force between the interlayer film and glass plate deteriorates

Engineering Contradiction:
Improvediscoloration resistanceVSAvoidadhesive force
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent uses local quality to concentrate the light stabilizer in the colored part where discoloration prevention is needed, while maintaining a lower concentration in the end part where adhesive force is critical. This localized distribution allows high discoloration resistance in the colored region without compromising the adhesive bond strength in the end region.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent segments the light stabilizer distribution into two zones: a colored part with higher light stabilizer content for discoloration protection, and an end part with lower light stabilizer content to preserve adhesive properties. This segmentation enables the film to achieve both discoloration resistance and adequate adhesive force.

Inventive Principle:
Principle #1Segmentation

3Productivity

If the interlayer film is exposed to light and heat to improve deaeration properties, then the deaeration efficiency is improved, but void generation at the end part increases

Engineering Contradiction:
Improvedeaeration efficiencyVSAvoidvoid generation
Core Design Contradiction:
ProductivityVSStability of the object's composition

Solution Approach 1:

The patent applies preliminary action by pre-distributing the light stabilizer in a non-uniform pattern before the lamination process. The end part is pre-loaded with sufficient light stabilizer to counteract the damaging effects of subsequent light and heat exposure during deaeration, thereby preventing void generation even when high deaeration efficiency is achieved through aggressive light and heat treatment.

Inventive Principle:
Principle #10Preliminary action

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 interlayer film effectively suppresses discoloration in the colored part and prevents void generation at the end parts of the laminated glass, enhancing the appearance and adhesive force between the interlayer film and glass plates.

Implementation Method 1

contains a light stabilizer in the non-colored part, wherein a content of the light stabilizer in the entire non-colored part is larger than a content of the light stabilizer in the entire colored part

Methodology Applied
Scientific EffectLight absorption: Absorption (EM radiation)

Implementation Method 2

discoloration can occur in the colored part... effectively suppresses discoloration in the colored part

Methodology Applied
Scientific EffectPhoto-oxidation prevention: Photo-oxidation

Data Source

PatentEP3636613B1Interlayer for laminated glass, and laminated glass
Publication Date: 2024.07.24 SEKISUI CHEMICAL CO LTD
  • EP3636613B1 patent drawingFigure 1~3
  • EP3636613B1 patent drawingFigure 4
  • EP3636613B1 patent drawing

AI summary

There is provided an interlayer film for laminated glass with which discoloration in the colored part can be suppressed. An interlayer film (1) for laminated glass according to the present invention has a colored part (X) that is colored in plan view, and a non-colored part (Y) that is not colored in plan view; the interlayer film does not contain or contains a light stabilizer in the colored part; the interlayer film contains a light stabilizer in the non-colored part; and a content of the light stabilizer in the entire non-colored part is larger than a content of the light stabilizer in the entire colored part.