Isophorone

I. Basic Characteristics

1. Chemical Nature

   • Chemical name: 3,5,5-Trimethyl-2-cyclohexen-1-one, molecular formula C₉H₁₄O, molecular weight 138.21, CAS No. 78-59-1.
   • Physical Properties:
     • Colorless to pale yellow transparent liquid with a characteristic camphor/mint-like odor;
     • Boiling point 213–215°C (atmospheric pressure), flash point 84–96°C (open cup), density 0.923–0.9255 g/cm³;
     • Insoluble in water but miscible with most organic solvents such as ethanol.
   • Chemical Properties:
     • Easily polymerizes into dimers upon exposure to light; oxidizes in air to form 4,4,6-trimethyl-1,2-cyclohexanedione;
     • Contains an α,β-unsaturated ketone structure, enabling participation in reactions such as hydrogenation and epoxidation.

2. Grades

   • Industrial Grade Purity: ≥99.5%, requires light-proof and sealed storage.

II. Core Application Areas

1. High-Boiling Solvent (Core Use)

• Paints and Inks:
  • Used as a solvent in nitrocellulose lacquers and epoxy resin coatings, providing high solvency and slow-drying properties to improve leveling;
  • Added to screen printing inks as a slow-drying agent to extend drying time.
• Industrial Cleaning:
  • Used for metal degreasing and equipment descaling, leveraging strong solvency to remove oil/resin residues.

2. Chemical Intermediate

• Polymer Synthesis:
  • Production of isophorone diisocyanate (IPDI), a key raw material for polyurethanes;
  • Synthesis of nylon polyamides and specialty fibers.
• Fine Chemicals:
  • Derivatized into isophorone oxide (epoxy structure), used in fragrances and pharmaceutical intermediates;
  • Preparation of pesticide intermediates (e.g., phenmedipham), 3,5-xylenol, and vitamin E.

3. Daily Chemicals and Fragrances

• Fragrance Formulation:
  • Used in blending daily chemical fragrances to provide woody notes;
• Special Applications:
  • Acts as an emulsifier in insecticides, enhancing emulsion stability and low volatility.

III. Product Advantages and Competitor Comparison

• Comparison with Cyclohexanone:

  Property	Isophorone	Cyclohexanone
  Boiling Point	215°C (higher)	155°C
  Solubility	Broader (resins/vinyl)	Moderate
  Cost	Lower	Higher (cyclohexane oxidation)
  Primary Use	Paint solvent/polymer precursor	Nylon intermediate

IV. Safety and Handling Guidelines

• Toxicity: Slightly toxic, irritates eyes/respiratory tract; air exposure limit ≤25 mg/m³ (5 ppm);
• Flammability: Flash point 84–96°C; handling requires anti-static measures and avoidance of open flames;
• Storage:
  • Sealed and light-proof, temperature <30°C to prevent oxidation and deterioration;
  • Avoid iron containers (to prevent corrosion).

Note: The derivative isophorone oxide (CAS 10276-21-8) is an epoxide compound used as an organic synthesis intermediate and requires separate safety evaluation.