# Plain vs impregnated carbon-graphite (resin and antimony)

Differences between base carbon-graphite (*00), resin-impregnated (*45), and antimony-impregnated grades: porosity, sealing, wear, and what ESGRAF needs to quote.

Source: https://esgraf.com/en/blog/carbon-graphite-plain-vs-impregnated

On seals, bushings, and friction faces, ordering “carbon-graphite” without saying whether it is **plain** or **impregnated** leaves the quote open to different densities, porosities, and service limits. In the MERSEN JP line ESGRAF supplies, carbon-graphite is one family: *00 codes are the base grade; resin and metal are impregnated variants of that same material.

This guide compares **plain vs impregnated carbon-graphite** with **resin** and **antimony** (and mentions copper or silver only as other metallic impregnations on the same datasheet). For general material context, see [carbon-graphite: what it is and uses](https://esgraf.com/en/blog/carbon-graphite-what-is-it-and-uses).

## The problem: confusing family with porosity finish

Purchasing can receive three “JP” offers that are not interchangeable: a porous base, a more hermetic *45 resin grade, and a denser metal-impregnated grade. On the floor the symptom is leakage, early wear, or a service temperature incompatible with the impregnant.

The right decision starts from **fluid, pressure, temperature, speed, and whether you need hermeticity or extra conductivity**.

## What the base grade is (plain, *00)

On [mechanical carbon-graphite](https://esgraf.com/en/materials/technical-graphite/carbon-graphite), base-grade examples include **JP600, JP900, and JP1300**. They are carbon-graphite without the resin or metal impregnation step.

They are sought when:

- The application accepts the grade’s open porosity
- There is dry friction or boundary lubrication where graphite contributes self-lubrication
- You want the starting point before deciding to impregnate

Typical datasheet ranges for the family (base and impregnated variants) include open porosity on the order of **2–20 %**, apparent density **1.68–1.90 g/cm³**, and flexural strength **50–90 MPa**, with thermal conductivity spanning a wide band by grade.

## Resin impregnation (*45)

Impregnation with **phenolic or epoxy resin under vacuum** closes porosity. In JP nomenclature, the ***45** suffix marks that variant (JP545, JP645, JP945, JP1345).

Typical datasheet ranges for resin:

- Apparent density: **1.85–1.95 g/cm³**
- Open porosity: **2–6 %**
- Flexural strength: **45–75 MPa**
- Thermal conductivity: **110–160 W/m·K**

It fits when you prioritize **lower porosity and better hermeticity** on mechanical seals, bearings, and components where the base grade lets too much fluid or gas through. Common formats: blocks, plates, and machined parts. See also [carbon graphite](https://esgraf.com/en/materials/technical-graphite/carbon-graphite).

## Antimony impregnation (and other metallics)

**Metallic** impregnation starts from the same *00 base grades. **Antimony** is a frequent option when you want better conductivity and wear resistance versus base or resin. The datasheet also contemplates other metallic impregnations such as **copper** or **silver**, depending on formulation and grade.

Typical datasheet ranges for metallic impregnation:

- Apparent density: **2.0–2.3 g/cm³**
- Open porosity: **1–4 %**
- Flexural strength: **50–80 MPa**
- Thermal conductivity: **150–250 W/m·K**
- Electrical conductivity: **80–150 S/cm**

It fits seals, [electrical contacts](https://esgraf.com/en/applications/electrical-contacts), and demanding friction parts where conductivity or wear dominates. Formats: blocks, rings, and plates.

## Practical comparison

| Criterion | Base (*00) | Resin (*45) | Metal (e.g. antimony) |
| --- | --- | --- | --- |
| Porosity | Higher (by grade) | Reduced | Very reduced |
| Hermeticity | Application-dependent | Improved | High in many cases |
| Density | Lower relative | Mid–high | Higher |
| Typical focus | Friction / starting point | Sealing / low porosity | Wear and conductivity |
| Key limit | Open porosity | Impregnant thermal compatibility | Metal and cycle compatibility |

These are datasheet trends, not absolute rules. Validate impregnant against temperature and chemical media against the [mechanical carbon-graphite](https://esgraf.com/en/materials/technical-graphite/carbon-graphite) datasheet.

## Where each option is used

- **Base:** [bushings and spacers](https://esgraf.com/en/applications/machine-bushings-spacers), dry friction, seal-face prototypes.
- **Resin:** [mechanical seal rings](https://esgraf.com/en/applications/pump-mechanical-seals) where porosity leakage is the problem.
- **Antimony / metal:** seals and contacts with higher wear or conductivity demand.

## Limitations to consider

- Impregnating does not automatically turn every base into “the best seal” for every fluid.
- Service temperature must respect impregnant limits, not only the carbon-graphite substrate.
- Cross-brand equivalences require comparing porosity, density, and impregnation type — not only the JP prefix.
- Inventory of impregnated blanks and impregnation lead times can differ from base stock.

## Information needed for a quote

- Application (seal, bushing, face, contact)
- Fluid or media, pressure, temperature, speed
- Current issue: leakage, wear, or other?
- Preference: base / resin / antimony (or other metallic)
- Dimensions or drawing; quantity
- Reference grade (a code photo helps)

## FAQ

### Are *00 and *45 different materials?

They are the same JP carbon-graphite family: *45 is the base impregnated with resin. They are not separate families in the ESGRAF catalog.

### Can I impregnate a base blank later?

Often yes, via [mechanical carbon-graphite](https://esgraf.com/en/materials/technical-graphite/carbon-graphite), depending on geometry and specification. Confirm before machining final tolerances.

### Resin or antimony for a pump seal?

It depends on temperature, fluid, and whether the failure mode is porosity leakage or wear. Bring operating conditions; do not choose on density alone.

### Do copper or silver replace antimony?

They are other possible metallic impregnations by grade. Equivalence is not automatic: quote by application.

### Does ESGRAF machine impregnated parts?

Yes. Formats and CNC parts to print are supplied in the [mechanical carbon-graphite](https://esgraf.com/en/materials/technical-graphite/carbon-graphite) family.

## Request a quote

If you need to choose between **plain carbon-graphite** and **resin- or antimony-impregnated** grades, [request a quote](https://esgraf.com/en/quote) or [contact us](https://esgraf.com/en/contact) with seal or bushing conditions. A specialist will guide you to the right grade and format.