Glass Article Coating With Controlled Ar Desorption for Molding

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Solution Overview

Problem

Glass articles with shielding layers may develop voids during heating and molding, leading to whitening and impaired external appearance due to gas desorption from the coating film.

Innovation Solution

A glass article with a silicon oxide-containing layer having controlled Ar desorption below 1.86 nm·atomic% at 550°C, a Bi/Si ratio of 3.8 or lower in the shielding layer, and specific layer compositions to prevent gas entrapment and void formation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a shielding layer is provided on the glass article to prevent adhesive deterioration and improve design, then protection and aesthetic properties are improved, but air bubbles form during heating-and-molding process causing voids and whitening that impair external appearance

Engineering Contradiction:
Improveprotection of adhesive from sunlight deteriorationVSAvoidwhitening and external appearance impairment
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies preliminary action by controlling the Ar desorption characteristics of the silicon oxide-containing layer before the heating-and-molding process. By ensuring that 95% or more of Ar desorption occurs at temperatures of 550°C or lower, the gas is removed in advance before the shielding layer is applied and before subsequent heating processes, preventing bubble formation and voids during later stages.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent utilizes parameter changes by precisely controlling the desorption temperature characteristics of Ar gas from the silicon oxide-containing layer. The key parameter is the desorption temperature distribution, where the patent specifies that the cumulative desorption amount at 550°C should be 95% or more of the total, thereby changing the thermal behavior of the coating layer to prevent harmful effects during heating.

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If the glass article undergoes heating-and-molding process to achieve desired shape, then formability is improved, but gas desorption from coating film creates air bubbles and voids that worsen external appearance

Engineering Contradiction:
Improveheating-and-molding processabilityVSAvoidexternal appearance quality
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent removes gas from the coating system in advance by designing the silicon oxide-containing layer to desorb Ar gas primarily at temperatures of 550°C or lower. This preliminary gas removal occurs before the main heating-and-molding process, preventing bubble formation during shaping operations while maintaining formability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent changes the thermal desorption parameters of the coating layer by controlling the silicon oxide-containing layer composition and structure. By adjusting the desorption temperature profile so that 95% or more of Ar is released at 550°C or below, the patent enables heating-and-molding processes to proceed without gas entrapment, thereby maintaining both manufacturability and appearance quality.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If the silicon oxide-containing layer has high Ar content to maintain coating properties, then coating performance is improved, but gas desorption above 550°C creates voids and whitening during heating processes

Engineering Contradiction:
Improvecoating film performanceVSAvoidgas desorption causing voids and whitening
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent changes the thermal desorption parameters of Ar gas from the silicon oxide-containing layer by controlling its composition and structure. Specifically, it adjusts the desorption temperature distribution so that 95% or more of Ar is released at 550°C or lower, thereby maintaining coating performance while preventing gas-related defects during subsequent heating processes.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent converts the potentially harmful Ar gas trapped in the coating layer into a beneficial element by controlling its desorption timing. The Ar gas, which would normally cause voids and whitening during heating, is instead released in advance at controlled temperatures, transforming from a harmful trapped gas into a beneficial pre-removed gas that prevents defects.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

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 solution effectively suppresses whitening, ensuring an excellent external appearance by minimizing gas desorption and void formation during heating and molding processes.

Implementation Method 1

an amount of desorption of Ar in the silicon oxide-containing layer above 550°C is 1.86 nm·atomic% or less

Methodology Applied
Scientific EffectDesorption: Desorption

Data Source

PatentEP4631922A1Glass article and production method for same
Publication Date: 2025.10.15 AGC INC
  • EP4631922A1 patent drawingFigure 1A~1C
  • EP4631922A1 patent drawingFigure 2
  • EP4631922A1 patent drawing

AI summary

A glass article having an excellent external appearance and capable of suppressing the occurrence of whitening after being subjected to heating and molding, and a method for manufacturing such a glass article are provided. A glass article according to the present disclosure comprises, on a glass substrate (1), a functional layer (3) and a silicon oxide-containing layer (4) in this order, wherein an amount of desorption of Ar in the silicon oxide-containing layer (4) above 550°C is 1.86 nm·atomic% or less. The glass article may comprise a dielectric layer (2) between the glass substrate (1) and the functional layer (3), and comprise a shielding layer (5) on the silicon oxide-containing layer (4). The glass article can be used as a window glass for automobile. Further, a method for manufacturing a glass article according to the present disclosure comprises forming, on a glass substrate (1), a functional layer (3) and a silicon oxide-containing layer (4) in this order by dry coating, wherein an amount of desorption of Ar in the silicon oxide-containing layer (4) above 550°C is adjusted to 1.86 nm·atomic% or less.