Parylene Coating Services
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CD Bioparticles is a high-tech enterprise specializing in parylene vacuum coating process development and product sales. We provide customized services for coating material development and coating processing.
CD Bioparticles is a leading global supplier of coating processing services, with advanced equipment and a professional technical team. For years, CD Bioparticles has been focusing on surface protection coating services for integrated circuit boards, magnetic cores, rubber products, aerospace materials, medical devices, etc. Parylene coating technology can be widely used in the fields of aerospace, new energy automobiles, circuit boards, magnetic materials, sensors, silicone rubbers, seals, medical devices, and precious relics. The products coated by parylene have extremely high insulating strength, high and low temperature resistance, acid and alkali corrosion resistance, lubrication, anti-adhesion, dust-proof, waterproof, moisture-proof, rust-proof, transparent, anti-aging, biocompatibility, etc. CD Bioparticles can design and customize the parylene vacuum coating equipment and matching products according to different needs of the customers, providing customers with a full range of parylene coating processing and vacuum coating customization services.
Today we offer you:
Parylene coatings are the most effective contemporary coating materials against moisture, mould, corrosion and salt spray. It can be applied to a wide range of material surfaces. If you are trying to improve the properties of a material to give it even better functionality, this is an excellent choice for coating fabrication supplies:
- Parylene raw material supply
- Parylene equipment sales
- Parylene coating processing (covering a wide range of aerospace, electronics, automotive and medical device sectors)
Introduction to Parylene Coatings
Parylene is also known as Parylene and poly-p-xylene. Parylene is a highly crystalline material with a complete structure, an extremely low dissipation factor, high dielectric strength, and low dielectric constant that does not change with frequency. Parylene is prepared by a unique vacuum vapor deposition process, which consists of reactive small molecules that form a completely shaped, extremely thin polymer coating on the surface of the substrate. It can be applied to a wide range of surface shapes, including sharp edges and cracks, and is highly resistant to degradation and biocompatible.
Types of Parylene Coatings
Due to the different molecular structures, parylene can be classified into various types such as N-type, C-type, D-type and HT-type.
Parylene-C, the second commercially viable member of the family. It is made from the same monomer, except that one of the aromatic hydrocarbon hydrogen atoms has been replaced by a chlorine atom.
Parylene-C is the best choice for:
- Circuit boards
- Coil motors
- LEDs
- OLEDs
- Medical implants
- Magnetic materials
- Sensors
Parylene-N is an excellent dielectric material with very low dielectric loss, high dielectric strength and a dielectric constant that does not vary with frequency. It has the highest penetration capacity of all parylene.
Parylene-N is the best choice for:
- Silicone rubber seals
- Silicone tubes
- Medical catheters
- Medical stoppers
- Silicone buttons
- Medical device
- Other silicone products
Parylene-D, the third member of the series. It is made from the same monomer, except that two of the aromatic hydrocarbon hydrogen atoms have been replaced by chlorine atoms. It has excellent dielectric and physico-mechanical properties at higher temperatures. It has high thermal stability.
Parylene-D is the best choice for:
- Microelectronic products
- Biomedical anti-corrosion products
- Cultural relics
Parylene-HT has a lower dielectric constant (i.e., good wave transmission). Good thermal stability for long term use at 350℃ and short term use at 450℃. Strong waterproof, mould proof and salt spray proof performance. Better protective coating for high frequency microwave devices. Strong self-lubrication, minimum coefficient of dynamic and static friction, and better lubrication than Teflon coating.
Parylene-HT is the Best Choice for:
- Implantable medical devices
- Aerospace and electronics
Performance Parameters of Parylene
Table 1. Comparison of Parylene's main properties with other resins.
| ASTM |
Parylene N |
Parylene C |
Parylene D |
Epoxy Resin (ER) |
Silicone Resin (SR) |
Polyurethane (UR) |
Polyacrylate |
| AR |
UV |
| Dielectric strength DC(V/mil) |
7000 |
5600 |
5500 |
900-1000 |
1100-2000 |
1400-3000 |
1200-2000 |
| Volume Resistance Ω.cm 23C 50%RH |
1.4x1017 |
6-8x1016 |
| 1016 |
1012-17 |
1015-16 |
1011-15 |
1013-14 |
| Surface resistance Q |
1013 |
1014 |
| 1016 |
1013 |
1013 |
|
1015 |
| Dielectric constant |
60Hz |
2.65 |
3.15 |
2.84 |
3.5-5.0 |
2.7-3.1 |
5.3-7.8 |
3-4 |
| 1 KHz |
2.65 |
3.10 |
2 |
3.5-4.5 |
2.6-2.7 |
5.4-7.6 |
2.5-5 |
| 1MHz |
2.65 |
2.95 |
2.80 |
3.3-4.0 |
2.6-2.7 |
4.2-5.2 |
3-4 |
| Dielectric loss |
60Hz |
0.0002 |
0.02 |
0.004 |
0.002-0.01 |
0.001-0.007 |
0.015-0.05 |
0.2-0.4 |
| 1 KHz |
0.0002 |
0.019 |
0.003 |
0.002-0.02 |
0.001-0.005 |
0.04-0.06 |
0.02-0.04 |
| 1MHz |
0.0006 |
0.013 |
0.002 |
0.03-0.05 |
0.001-0.002 |
0.05-0.07 |
0.035-0.056 |
| Friction coefficient |
Static |
0.25 |
0.29 |
0.33 |
|
1.0 |
|
|
| Dynamic |
0.25 |
0.29 |
0.31 |
|
1.0 |
|
|
| Melting point (°C) |
420 |
290 |
380 |
Curing |
Curing |
170 or Cure |
|
| Young's modulus (Mpa) |
2400 |
3200 |
2800 |
2400 |
720 |
80-800 |
480 |
| Tensile strength (Mpa) |
45 |
70 |
75 |
28-91 |
5.6-7 |
1.13-70 |
32-77 |
| Elongation at break (%) |
20-250 |
200 |
10 |
3-6 |
100 |
100-1000 |
3-85 |
Table 2. Thickness changes (%) produced by immersion of 0.5-1.5 MIL films in various solvents for 90 minutes at room temperature (IR measurements).
| Solvents |
Thickness variation of Parylene |
| |
Parylene N |
Parylene C |
Parylene D |
| Isopropanol |
0.3 |
0.1 |
0.1 |
| Isooctane |
0.2 |
0.4 |
0.3 |
| Pyridine |
0.2 |
0.5 |
0.5 |
| Mixed xylenes |
1.4 |
2.3 |
1.1 |
| Trichloroethylene |
0.5 |
0.8 |
0.8 |
| Chlorobenzene |
1.1 |
1.5 |
1.5 |
| Dichlorobenzene |
0.2 |
3.0 |
1.8 |
| Trichlorotrioxane |
0.2 |
0.2 |
0.2 |
| Acetone |
0.3 |
0.9 |
0.4 |
| 2,4-Pentanedione |
0.6 |
1.2 |
1.4 |
| Deionised water |
0 |
0 |
0 |
Table 3. Thickness change (%) of 0.5-1.5 MIL films after immersion in various solvents for 90 minutes at room temperature (infrared measurement).
| |
Thickness variation of Parylene |
| Reagent species |
Parylene N(%) |
Parylene C(%) |
Parylene D(%) |
| Hydrochloric acid (HCl, 10%) |
0.0 |
0.0 |
0.1 |
| Concentrated hydrochloric acid (HCl, 37%) |
0.2 |
0.0 |
0.5 |
| Sulphuric acid (H2SO4, 10%) |
0.1 |
0.3 |
0.2 |
| Concentrated Sulphuric Acid (H2SO4, 95-98%) |
0.2 |
0.4 |
0.8 |
| Nitric acid (HNO3, 10%) |
0.1 |
0.1 |
0.2 |
| Concentrated Nitric Acid (HNO3, 71%) |
0.2 |
0.2 |
0.5 |
| Chromic acid (H2CrO4, 10%) |
0.1 |
0.1 |
0.1 |
| Concentrated chromic acid (H2CrO4, 74%) |
0.3 |
0.0 |
0.2 |
| Strong base (NaOH, 10%) |
0.1 |
0.0 |
0.1 |
| Weak base (NH4OH, 10%) |
0.3 |
0.2 |
0.1 |
Advantage of Parylene Coatings
- Highly biocompatible and stable (anti-bacterial)
- Protected against dust and water, IP rating up to 6 8
- Resistant to chemical attack (fluids, gases, liquids)
- Resistant to dissolution (will not dissolve in common solvents)
- Resistant to high temperatures (operating temperatures up to 120-350℃) and cold (-120℃ below zero)
- Unrivalled barrier effect (low gas permeability)
- Extremely high dissipation coefficient and heat dissipation characteristics.
- Uniform, transparent and extremely thin coating
- Applied to various shapes of surfaces, including sharp edges and inside cracks
- Economic and clean, simple process, high speed, high batch processing capability
Figure 1. Difference in film thickness uniformity between parylene(right) and normal coatings(left).
| Normal Coating |
Parylene coating |
| Uneven film thickness, shape change |
Uniform film thickness, same shape |
| Insufficiently covered dead-end edges |
Good perimeter coverage, no holes |
| Shrinkage pressure of heat hardening cannot be tolerated |
Constant room temperature without any shrinkage pressure |
| Not Environmentally friendly: Harmful to the human body |
Environmentally friendly: FDA approved coating for implantable human materials |
Markets of Parylene Coatings
Parylene coatings possess thermal properties, low temperature properties, optical properties, radiation resistance, water and gas barrier, dielectric properties and abrasion resistance, etc. Its excellent performance meets the coating needs of medical devices, electronics and aerospace fields. With a low coefficient of friction, the coating meets the requirements of ISO-10993 for biological testing and FDA G95-1. For example, some implantable medical products coated with parylene do not have any toxic side effects.
- Implantable Medical Devices
Parylene is a chemically inert and biocompatible high-purity coating material, which can be used for various types of in vivo implants (bone nails, bone plates, pacemakers, vascular stents and surgical knives, etc.), and devices coated with it can improve surface lubrication, biocompatibility, and stability. At the same time very good corrosion resistance, can avoid guide wire or metal in human contact with body fluids and corrosion.
Printed circuit boards are the wider application of parylene, which meets the XY-type standards of the U.S. Military Standard Mil-l-46058C, and protects the sensitivity of circuit boards. In addition, parylene can also be used as a passivation layer and dielectric layer for microelectronics and semiconductors, providing safe and stable protection. Like LED light bar, LED light module, LED display after parylene coating, it can achieve moisture-proof, waterproof, dust-proof, acid and alkali resistance, resistance to high voltage and dry lubrication effect. That can achieve the relevant requirements of the IP grade to enhance the service life of the product and the use of the effect.
Parylene can change the friction properties, tactility, chemical swelling resistance, and static breakdown resistance of rubber products. After coating with parylene, the products have good barrier properties, optical properties, thermal properties and good friction resistance, so that the product life is extended.
Sensitive electronic devices such as blood pressure sensors can be adequately insulated by depositing a small amount of parylene. The small amount of protective coating does not significantly alter the operation of these devices.
- Artifacts and Antiquarian Books
Parylene is a high crystallinity transparent film material, directly coated on the protected specimens, without the need to add another anti-mould agent, its own anti-mould can reach zero level. After being reinforced with parylene, precious books can be preserved for a long time, reducing the chance of breakage when the books are flipped through.
Electronic components such as ferrite materials (rings, cores), NdFeB rare-earth magnetic materials and other magnetic materials such as samarium cobalt can usually use parylene as insulation and protective coating. The coated magnets have strong adhesion, can effectively reduce the wear and tear of the magnetic material in the winding, enhance the strength of the magnets, reduce the chance of samarium cobalt magnets shattering. At the same time, it can achieve a certain corrosion-resistant effect.
- Military/Aeronautical/Space/Automotive Materials
Paraline is a military standard protective coating that eliminates moisture, metal ions and other particulate contamination from surfaces, as well as providing insulation and corrosion protection. It enhances the conformability of COTS devices without increasing the cost. Paraline-N, C and HT are listed in the Defence Supply Centre Columbus Parts List (QPL) MIL-I-46058 and are also considered to meet the requirements of IPC-CC-830.
