Working fluid composition and refrigerator

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing refrigerating machine working fluid compositions using unsaturated hydrofluorocarbon refrigerants like HFO-1234yf lack stability and refrigerant dissolution viscosity, necessitating improved formulations.

Innovation Solution

A novel working fluid composition comprising a refrigerating machine oil with specific base oils (polyol ester and polyvinyl ether) and additives (carbodiimide-based acid scavenger and phenol-based antioxidant) combined with refrigerants HFO-1132(E) and HFO-1234yf, optimized for refrigerant fraction and viscosity conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If conventional refrigerants like R134a or R125 are used, then refrigeration performance is maintained, but global warming potential and ozone depletion issues occur

Engineering Contradiction:
Improveglobal warming potentialVSAvoidrefrigeration performance
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent uses composite refrigerant formulations combining HFO-1234ze(E) as the base refrigerant with specific proportions of R125 (5-15 mass%), R134a (5-30 mass%), and R32 (5-20 mass%). This composite approach maintains refrigeration performance while achieving low GWP values below 150, resolving the contradiction between environmental protection and system reliability.

Inventive Principle:
Principle #40Composite materials

2Object-affected harmful factors

If natural refrigerants like propane or isobutane are used, then environmental friendliness is improved, but flammability hazards increase

Engineering Contradiction:
Improveozone depletion potentialVSAvoidflammability
Core Design Contradiction:
Object-affected harmful factorsVSObject-generated harmful factors

Solution Approach 1:

The patent applies local quality by assigning different functional roles to each refrigerant component: HFO-1234ze(E) provides base cooling with non-flammable properties, R125/R134a/R32 enhance refrigeration efficiency in controlled proportions, and the specific composition ranges ensure the mixture remains non-flammable while maintaining excellent refrigeration performance and zero ozone depletion potential.

Inventive Principle:
Principle #3Local quality

3Object-affected harmful factors

If HFO-1234ze(E) is used as pure refrigerant, then GWP is reduced below 150, but refrigeration performance and lubricating oil compatibility deteriorate

Engineering Contradiction:
Improveglobal warming potentialVSAvoidrefrigeration performance
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent changes the compositional parameters by formulating a multi-component mixture where HFO-1234ze(E) constitutes 65-90 mass% to maintain low GWP below 150, while precisely controlling the addition of R125 (5-15 mass%), R134a (5-30 mass%), and R32 (5-20 mass%) to optimize refrigeration performance, heat transfer characteristics, and lubricating oil compatibility, thereby resolving the performance deterioration issue.

Inventive Principle:
Principle #35Parameter changes

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

Enhances refrigerant dissolution viscosity and stability under specified temperature and pressure conditions, surpassing compositions using HFO-1234yf alone and other oils, ensuring superior performance in refrigerating machines.

Implementation Method 1

a refrigerant composition comprising a compound of formula (1) and/or its stereoisomers, or a mixture containing a compound of formula (1) and/or its stereoisomers as an active substance

Methodology Applied
Scientific EffectHeat absorption: Absorption (physical)

Implementation Method 2

wherein R1 to R6 independently represent a hydrogen atom or a methyl group, with the proviso that R1 and R2, R3 and R4, or R5 and R6 are not two methyl groups, respectively

Methodology Applied
Scientific EffectHeat release: Heating

Implementation Method 3

improving the global warming potential and the ozone depletion potential

Methodology Applied
Scientific EffectPhase change: Phase Change

Data Source

PatentEP4606879A1Working fluid composition and refrigerator
Publication Date: 2025.08.27 ENEOS CORP
  • EP4606879A1 patent drawingFigure 1
  • EP4606879A1 patent drawingFigure 2
  • EP4606879A1 patent drawing

AI summary

A working fluid composition containing a refrigerating machine oil; and a refrigerant containing trans-1,2-difluoroethylene (HFO-1132(E)) and 2,3,3,3-tetrafluoropropene (HFO-1234yf), wherein the working fluid composition has a refrigerant fraction at 80°C and 2.5 MPa of 80% by mass or less, wherein the refrigerating machine oil contains: at least one base oil selected from the group consisting of a polyol ester and a polyvinyl ether; a carbodiimide-based acid scavenger; and a phenol-based antioxidant.