Highlight｜CAS 220426-92-6 (M-6FDAP) Fluorinated Diamine Monomer: Advancing Local Photosensitive Polyimide Development

Against the backdrop of rapid iteration in 5G high-frequency communication, advanced semiconductor packaging, optoelectronic devices, and aerospace high-temperature resistant materials, the industry imposes stringent multi-fold requirements on polyimide materials: lower dielectric loss, higher thermal stability, excellent photosensitivity, and high film transparency. As the core material for chip passivation layers, redistribution layers (RDL), and optical protective films, photosensitive polyimide (PSPI) has its performance ceiling highly dependent on specialized functional diamine monomers.

2,2-Bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, known as M-6FDAP (CAS: 220426-92-6), is a fluorinated aromatic diamine monomer bearing phenolic hydroxyl functional groups. Benefiting from its specially designed molecular structure, it effectively addresses the drawbacks of conventional polyimides and serves as a critical raw material for the synthesis of high-performance negative-type photosensitive polyimide. It helps China’s optoelectronic material supply chain reduce import reliance and achieve localized mass production.

     Product Overview

    CAS No.: 220426-92-6

    Chinese Name: 2,2-Bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane

    English Name: 2,2-Bis(3-(3-aminobenzoylamino)-4-hydroxyphenyl)hexafluoropropane

    Molecular Formula: C₂₉H₂₂F₆N₄O₄

Its molecular structure integrates a hexafluoroisopropyl backbone, aromatic amide structure and active phenolic hydroxyl sites. Amino groups provide reactive sites for polymerization with dianhydride monomers; phenolic hydroxyl groups endow photolithographic crosslinking properties; fluorinated moieties reduce molecular polarizability and suppress tight packing of molecular chains, balancing solubility, light transmittance and dielectric performance. The industrial grade of this product features high purity, low metal ion content and controllable particulate impurities, meeting synthesis requirements for electronic-grade materials and capable of matching overseas equivalent monomer products.

      Core Performance Advantages

    1. Excellent Photolithographic Photosensitivity

The molecule inherently contains phenolic hydroxyl groups. In negative-type photosensitive polyimide systems, it can react with photo-crosslinkers to form well-defined fine patterns during photolithography and development. It delivers high pattern resolution to satisfy micron-scale patterning in semiconductor microfabrication, minimizing residual photoresist and edge burrs, and is compatible with chip passivation and wafer protection processes.

     2.Low Dielectric Constant & Low Water Absorption from Fluorinated Structure

The introduction of fluorinated groups effectively reduces the dielectric constant and dielectric loss of materials, mitigating signal transmission delay at high frequencies. Meanwhile, it significantly cuts the water absorption of polyimide films, suppressing device leakage and performance drift induced by moisture, and enabling long-term stable operation of high-frequency communication components.

    3.Outstanding Thermal Stability

Synergistic effects of aromatic rings, amide linkages and fluorinated backbone render polyimide films polymerized from this monomer high thermal decomposition temperature and superior glass transition temperature. The film can withstand chip reflow soldering and high-temperature curing processes without blistering or cracking, suitable for high-temperature post-processing conditions.

    4. Good Solubility & Processability

Compared with conventional rigid aromatic diamines, fluorinated groups disrupt the regularity of molecular chains. The resulting polyimide is soluble in multiple polar organic solvents, which facilitates formulation into varnish and spin-coating for film formation. It simplifies production workflows and eliminates harsh high-temperature film-forming conditions.

    5.Low Metal Ions, Electronic-Grade Compatibility

Adopted controlled purification process keeps metallic impurities such as potassium, sodium and iron at low levels, with strict particle control. It prevents reliability failures caused by metal ion migration in semiconductor devices, applicable to wafer-level electronic material scenarios.

       Main Application Fields

   1. Negative-type Photosensitive Polyimide (PSPI)

This is the primary application of M-6FDAP. Copolymerized with various aromatic dianhydrides as a diamine monomer to produce negative photosensitive polyimide resin. It is used for parotective films on semiconductor chip surfaces, insulating films for redistribution layers (ssivation pRDL), and temporary wafer protective coatings to realize photolithographic patterning, acting as an essential raw material of photoresist materials for advanced packaging.

   2. Optoelectronic and Display Device Materials

Applied in high-performance optical polyimide films and flexible display substrates. It improves UV-visible light transmittance of films, reduces chromaticity, and enhances weather resistance and heat resistance of membranes, suitable for insulating protective layers of flexible optoelectronic components.

    3. High-Frequency Communication Functional Materials

Used as insulating substrates for 5G/6G communication modules. Leveraging low-dielectric and low-loss properties, it fabricates high-frequency polyimide composite materials to guarantee transmission quality of high-frequency signals.

   4. Special High-Temperature Resistant Composite Materials

Designed for coatings on special aerospace components, with resistance to alternating high and low temperatures and radiation environments. As a functional monomer for polyimide resins, it manufactures insulating protective materials for extreme environment applications.

    Product Supply & Handling Notes

              Form: Solid powder

              Available grades: Lab small trial scale, kilogram-scale pilot batches

Storage: Store in a sealed, light-proof, cool and dry environment to avoid moisture and oxidation. Inert gas protection is recommended for long-term storage.

Safety Reminder: Fine chemical intermediate. Wear protective gloves and goggles during operation; avoid inhalation of dust.

Quality Support: Certificate of Analysis (COA) is available, covering key indicators including HPLC purity, metal ion content and moisture. Customized specification negotiation is supported.

    Summary of Industry Value

With rapid capacity expansion of domestic advanced semiconductor packaging and flexible optoelectronic industries, the localization of photosensitive polyimide is accelerating. Upstream high-performance functional diamine monomers have become a bottleneck in the industrial chain.

CAS 220426-92-6 (M-6FDAP) combines multiple structural merits: photosensitive hydroxyl groups, fluorinated modification and rigid aromatic amide backbone. It addresses the pain point that ordinary polyimides cannot simultaneously achieve good photolithography performance, heat resistance and low dielectric properties. Stable domestic supply helps resin manufacturers shorten R&D cycles and reduce raw material costs, accelerating import substitution of domestic PSPI materials and empowering high-quality development of the whole semiconductor and optoelectronic industrial chain.