Preservative Solvent Blend to Prevent Ortho-Cymen-5-Ol Recrystallization

Solution Overview

Problem

4-isopropyl-3-methyl-phenol (ortho-cymen-5-ol) has limited solubility in hydrophilic solvents and tends to recrystallize during storage, requiring a heating step for incorporation into formulations, which is undesirable for surfactant-based products.

Innovation Solution

A preservative mixture comprising 4-isopropyl-3-methyl-phenol with a specific ratio of hydrophilic and lipophilic solvents, where the log P O/W difference is at least 0.5, improving solubility and reducing recrystallization.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If ortho-cymen-5-ol is dissolved in hydrophilic solvents, then solubility is improved, but recrystallization tendency increases and stability deteriorates

Engineering Contradiction:

Improvesolubility of ortho-cymen-5-olVSAvoidstability against recrystallization

Core Design Contradiction:

Quantity of substanceVSStability of the object's composition

Solution Approach 1:

The patent uses a lipophilic solvent as an intermediary substance to facilitate the dissolution of ortho-cymen-5-ol in hydrophilic solvents. The lipophilic solvent acts as a mediator that bridges the hydrophobic preservative and hydrophilic formulation components, enabling complete dissolution without heating while preventing recrystallization during storage.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the chemical composition parameters by introducing a lipophilic solvent with specific log P0/w properties (above 1.2) into the hydrophilic solvent system. This parameter change modifies the overall solvation environment, allowing ortho-cymen-5-ol to remain dissolved at lower temperatures and preventing phase separation or recrystallization during storage.

Inventive Principle:

Principle #35Parameter changes

2Quantity of substance

If heating is applied to dissolve ortho-cymen-5-ol, then solubility is improved, but energy consumption increases and process complexity increases

Engineering Contradiction:

Improvesolubility of ortho-cymen-5-olVSAvoidenergy consumption for heating

Core Design Contradiction:

Quantity of substanceVSUse of energy by moving object

Solution Approach 1:

The patent applies preliminary action by pre-mixing ortho-cymen-5-ol with a lipophilic solvent before adding it to the hydrophilic formulation. This preliminary solubilization step creates a stable intermediate mixture that can be incorporated into the final product without requiring subsequent heating, thereby eliminating energy consumption and process complexity associated with thermal dissolution.

Inventive Principle:

Principle #10Preliminary action

3Quantity of substance

If heating is applied to dissolve ortho-cymen-5-ol, then solubility is improved, but device complexity and operational difficulty increase

Engineering Contradiction:

Improvesolubility of ortho-cymen-5-olVSAvoidease of incorporation into formulation

Core Design Contradiction:

Quantity of substanceVSEase of operation

Solution Approach 1:

The patent applies preliminary action by pre-mixing ortho-cymen-5-ol with a lipophilic solvent before adding it to the hydrophilic formulation. This preliminary solubilization step creates a stable intermediate mixture that can be incorporated into the final product without requiring subsequent heating, thereby eliminating energy consumption and process complexity associated with thermal dissolution.

Inventive Principle:

Principle #10Preliminary action

4Quantity of substance

If lipophilic solvent is added to hydrophilic solvent, then solubility of ortho-cymen-5-ol is improved, but formulation complexity increases

Engineering Contradiction:

Improvesolubility of ortho-cymen-5-olVSAvoidformulation composition complexity

Core Design Contradiction:

Quantity of substanceVSDevice complexity

Solution Approach 1:

The patent changes the chemical composition parameters by introducing a lipophilic solvent with specific log P0/w properties (above 1.2) into the hydrophilic solvent system. This parameter change modifies the overall solvation environment, allowing ortho-cymen-5-ol to remain dissolved at lower temperatures and preventing phase separation or recrystallization during storage.

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

The mixture allows for easier incorporation of 4-isopropyl-3-methyl-phenol into formulations without a heating step, enhancing stability and preventing recrystallization.

Implementation Method 1

A preservative mixture comprising ortho-cymen-5-ol, a hydrophilic solvent with a log P0/w of 1.2 or below, and a lipophilic solvent with a log P0/w above 1.2, significantly increasing solubility and reducing recrystallization by optimizing solvent ratios

Methodology Applied

Scientific EffectSolubility optimization through solvent mixture: Solvation

Data Source

PatentEP3500236B1A preservative mixture

Publication Date: 2026.05.06 SYMRISE GMBH & CO KG

Figure 1~2
Figure 3~4E
Figure 5

AI summary

Suggested is a preservative mixture with improved solubility comprising or consisting of (a) 4-isopropyl-3-methylphenol; (b) at least one hydrophilic solvent having a log Po/w of 1.2 or below; and (c) at least one lipophilic solvent having a log Po/w of above 1.2.