NP342 Canvas Phenolic Laminate Sheet
NP342 Canvas Phenolic Laminate Sheet is a fine weave canvas phenolic material with a fabric construction weight intermediate between NP310 and NP320, certifiable to ANSI/NEMA IM 60000-2021 Grade C, MIL-I-24768/16, ASTM D709 Type II Grade C, and IEC-60893-4-PF CC 201. The material is designed for better machining than NP310 and lower cost than NP320, delivering a flexural strength of 25,000 / 22,700 psi (LW/CW) and a compressive strength of 35,000 psi flatwise. Not UL Listed.
Key Properties
- Flexural Strength, Condition A LW / CW: 25,000 / 22,700 psi (172.4) / (156.5) MPa (ASTM D790)
- Flexural Modulus, Condition A LW / CW: 1,700 / 1,300 kpsi (11.7) / (9.0) GPa (ASTM D790)
- Tensile Strength, Condition A LW / CW: 12,700 / 10,900 psi (87.6) / (75.2) MPa (ASTM D638)
- Izod Impact Strength, Condition E-48/50 LW / CW: 1.60 / 1.40 ft-lb/in (0.85) / (0.75) J/cm (ASTM D256)
- Compressive Strength, Condition A Flatwise: 35,000 psi (241.3) MPa (ASTM D695)
- Temperature Index — Electrical / Mechanical: 125 / 125°C (UL Bulletin 746b)
We want to help!
Enter your information and we'll get you in touch with our knowledgable staff. We know how important to the right product for your project.
Request a Consultation
- Specifications
- Applications
- General Info
- FAQs
Physical Properties
| Property | Value | Test Method |
| Specific Gravity | 1.35 | ASTM D792 |
| Rockwell Hardness (0.250″ Build-up) | 100 M Scale | ASTM D785 |
| Moisture Absorption, Condition D₁-24/23 | 1.80% | ASTM D570 |
| Flexural Strength, Condition A LW / CW | 25,000 / 22,700 psi (172.4) / (156.5) MPa | ASTM D790 |
| Flexural Modulus, Condition A LW / CW | 1,700 / 1,300 kpsi (11.7) / (9.0) GPa | ASTM D790 |
| Tensile Strength, Condition A LW / CW | 12,700 / 10,900 psi (87.6) / (75.2) MPa | ASTM D638 |
| Izod Impact Strength, Condition E-48/50 LW / CW | 1.60 / 1.40 ft-lb/in (0.85) / (0.75) J/cm | ASTM D256 |
| Compressive Strength, Condition A Flatwise | 35,000 psi (241.3) MPa | ASTM D695 |
| Bonding Strength, Condition A | 1,900 lb (861.8) kg | ASTM D229 |
| Shear Strength, Condition A Perpendicular | 14,000 psi (96.5) MPa | ASTM D732 |
Thermal Properties
| Property | Value | Test Method |
| Temperature Index — Electrical / Mechanical | 125 / 125°C | UL Bulletin 746b |
| Coefficient of Thermal Expansion, X-axis / Y-axis | 20.0 / 22.0 (“/”/°C × 10⁻⁶) | IPC-TM 650-2.4.24 |
| Flammability Rating, Condition A | HB | UL Bulletin 94 |
Electrical Properties
| Property | Value | Test Method |
| Breakdown Voltage, Condition A | 40 kVolts | ASTM D149 |
| Breakdown Voltage, Condition D-48/50 | 3 kVolts | ASTM D149 |
| Electric Strength, Condition A | 550 Volts/mil (216.5) kV/cm | ASTM D149 |
| Electric Strength, Condition D-48/50 | 300 Volts/mil (118.1) kV/cm | ASTM D149 |
Compliance
- ANSI/NEMA IM 60000-2021 Grade C — Certifiable
- MIL-I-24768/16 — Certifiable
- ASTM D709 Type II Grade C — Certifiable
- IEC-60893-4-PF CC 201 — Certifiable
- Precision-machined phenolic components requiring better surface finish than NP310
- Structural and mechanical insulating parts at intermediate cost
- Gears, washers, and mechanical components requiring NEMA Grade C compliance
- Electrical insulation panels and structural supports
- Military and industrial applications requiring MIL-I-24768/16 at lower cost than NP320
Common industries: Electrical Equipment Manufacturing, Defense, Industrial Manufacturing, Mechanical Power Transmission, General Engineering.
NP342 Canvas Phenolic Laminate Sheet is a fine weave canvas phenolic laminate positioned intermediate in construction weight between the heavier canvas NP310 and the fine linen NP320 — designed specifically to offer better machinability than NP310 while remaining more cost-effective than NP320.
The fine weave construction enables cleaner machined surfaces and tighter dimensional control on precision components compared to NP310, making NP342 suitable for applications that require a NEMA Grade C canvas phenolic with improved machinability but do not require the fine linen construction or cost level of NP320.
Flexural strength reaches 25,000 / 22,700 psi (LW/CW) — higher than both NP310 and NP320 — and compressive strength is 35,000 psi flatwise.
The temperature index is 125°C electrical / 125°C mechanical — 10°C higher electrically than NP310 — and moisture absorption is 1.80%, significantly lower than NP310’s 3.50%. Flammability is rated HB per UL Bulletin 94. NP342 is not UL Listed.
Certifiable to ANSI/NEMA IM 60000-2021 Grade C, MIL-I-24768/16, ASTM D709 Type II Grade C, and IEC-60893-4-PF CC 201.
What differentiates NP342 Canvas Phenolic Laminate Sheet from NP310 and NP320?
NP342 is positioned intermediate between NP310 and NP320 in fabric construction weight. It offers better machinability than NP310 (heavier canvas construction, lower surface finish quality) and lower cost than NP320 (fine linen, highest machining quality). NP342 also delivers the highest flexural strength in the canvas phenolic Grade C line at 25,000 / 22,700 psi (LW/CW), and a temperature index of 125/125°C — higher electrically than NP310 (115°C). Unlike NP310, NP342 is not UL Listed.
Why does flexural strength matter when selecting a canvas phenolic laminate?
Flexural strength determines how much load a laminate panel or component can sustain before permanent deformation or fracture — a critical property for structural insulation panels, mounting supports, and mechanical components under sustained bending loads. NP342's flexural strength of 25,000 / 22,700 psi (LW/CW) exceeds both NP310 (18,000 / 17,000 psi) and NP320 (24,500 / 18,500 psi), making it the strongest phenolic Grade C option in the canvas laminate family for applications governed by bending load capacity.
What is the temperature index for NP342 Canvas Phenolic Laminate Sheet?
The temperature index is 125°C electrical / 125°C mechanical, as listed on the Technical Datasheet.
Is NP342 Canvas Phenolic Laminate Sheet suitable for military and regulated environments?
Yes. NP342 is certifiable to ANSI/NEMA IM 60000-2021 Grade C, MIL-I-24768/16, ASTM D709 Type II Grade C, and IEC-60893-4-PF CC 201. NP342 is not UL Listed and carries a UL 94 HB flammability rating — applications requiring UL Listing should specify NP310 (Postville, IA manufactured material).
How should NP342 Canvas Phenolic Laminate Sheet be specified?
Specify grade (NP342 Canvas Phenolic Laminate Sheet), thickness, compliance requirements (NEMA Grade C, MIL-I-24768/16, or ASTM D709 as applicable), dimensional tolerances, and finished format.
