The Impact of Isola FR370HR in Electronics Production

There are different kinds of laminates used in the production of electronic devices. However, some laminates offer more properties than others. Also, some laminates have better performance. Therefore, they are widely used in high-performance applications. Furthermore, the Isola FR370HR is an example of such a board. This article aims to shed more light on Isola FR370HR and its properties.

What is Isola FR370HR?

The Isola FR370HR laminate comprises a 180°C Tg FR-4 system. This board is ideal for multilayer PCB applications that require great thermal performance. Also, the Isola 370HR and prepreg products feature multifunctional epoxy resin with E-glass fiber fabric reinforcement. This lead-free compatible laminate is ideal for high-reliability applications across various markets.

Furthermore, Polyclad designed the Isola FR370HR prepregs and laminates. The Isola 370HR comprises high quality electrical grade glass fabric for conductive anodic filament (CAF) resistance. Also, this laminate features low CTE and exceptional thermal performance. In addition, 370HR Isola features chemical and mechanical properties that exceed that of FR4 materials.

Also, this laminate has proved to be the most efficient in terms of thermal stability and CAF resistance. Also, it has great performance on sequential lamination designs. Isola FR370HR is UV blocking and laser fluorescing for great compatibility with AOI.


Reques Isola FR370HR PCB Quote , Pls Send PCB Files to Now



Properties of Isola FR370HR

Isola FR370HR has great mechanical and chemical properties. Furthermore, this board is ideal in applications that require maximum thermal performance. Below are the properties of Isola FR370HR:

High glass temperature (Tg)

One of the properties of this laminate is its high thermal performance. According to Isola 370HR data sheet, this laminate features 180 degree Celsius glass temperature (Tg).


The coefficient of thermal expansion (CTE) in Isola FR370HR is very low. CTE describes the extent to which a laminate expands in response to heat. The Isola FR370HR can withstand heat without increasing in size.

Low dielectric constant

Dielectric constant (Dk) measures how a laminate can store energy in an electric field. The Isola FR370HR features a low dielectric constant.

CAF resistance

Conductive anodic filament is a concern in the electronics industry. Furthermore, it occurs when a conductive salt that contains copper forms within a circuit board. Isola FR370HR is resistant to conductive anodic filament (CAF). It eliminates the risk of CAF when used in any application.

Copper Foil Types Used in Isola 370HR

Isola FR370HR uses different types of copper foils like:

Reverse Treat Foil (RTF)

This type of copper foil involves treatment of the electrodeposited copper’s polished face. Also, the traditional RTF comprises a RSAR that ranges between 1.0 and 1.2. RSAR means Roughness Surface Area Ratio.  Also, RTF is smoother than other copper foil. However, it is vulnerable to delamination.

HTE Grade 3

HTE is a High Elongation Electrodeposited copper. This type of copper foil is IPC-4562 grade 3. Also, HTE has a semi-matt exterior face. This copper foil features anti tarnish treatment to reduce oxidation and corrosion during storage.


Reques Isola FR370HR PCB Quote , Pls Send PCB Files to Now



Mechanical Properties to Consider in Isola FR370HR

Flexural strength

This measures the ability of 370HR to tolerate mechanical stress without any fracturing. Also, the unit of measurement is always force per unit area. The IPC-4101 standard describes the least flexural strength of materials used in multilayer and rigid boards.

Tensile modulus

Manufacturers can determine the strength of 370HR Isola material by applying tensile modulus. This property evaluates the stress ratio in a particular direction. The unit of measurement for tensile modulus is force per unit area.

Peel strength

This measures the bond strength between the copper conductor and dielectric material. It is measures in the average load per conductor width. Manufacturers carry out peel strength tests after the fabrication process. Also, this test is ideal after thermal stress and at increased temperature. Therefore, this test is ideal after exposing FR4 370HR to heat at 125°C.

Thermal Analysis of Isola FR370HR

There are different techniques for analyzing the thermal performance of Isola 370HR. These techniques include:

Thermal mechanical analysis

This analysis is ideal for measuring Isola HR370’s glass transition temperature. However, this analysis determines the expansion of the material to measure Tg. A change in the Z-axis expansion rate accompanies the Tg. Most thermoset materials have around 500% increase in post Tg expansion rate.

Dynamic mechanical analysis

This evaluates the modulus properties and the energy dissipation of Isola FR370HR. Dynamic mechanical analysis provides quantitative and qualitative details over the Isola performance. Also, this thermal analysis is ideal in analyzing the mechanical properties of viscoelastic polymeric PCB materials. These are materials that have frequency and temperature effects.

This analysis offers glass temperature at 5 to 15°C. Therefore, it is an ideal method for determining the mechanical characteristics of Isola materials. Isola 370HR PCB manufacturers prefer this technique.

Differential scanning calorimetry

This is a commonly used analysis technique. Also, it determines the glass transition temperature of Isola material. Also, it determines the inflow and outflow of heat of a PCB material. The changes in heat flow identify an thermodynamic change.

Thermal Gravimetric Analysis

This measures the temperature degradation of 370HR Isola material. Also, the thermal gravimetric analysis measures the change in weight against temperature. In addition, degradation temperature occurs where a 5% weight loss occurs in 370HR material.

Furthermore, PCB degradation occurs over a wide range of temperatures.  Also, irreversible chemical bonds breakdown in the polymer structure can result in degradation. Therefore, laminates with greater degradation temperature have increased thermal stability.


Reques Isola FR370HR PCB Quote , Pls Send PCB Files to Now



What is the Best Desmear Method for Isola 370HR?

There are different methods of desmearing Isola 370HR. Also, Desmearing involves constant etching of the resin system. This process offers an improved hole wall texture if properly done. However, plasma desmearing is more ideal for 370HR Isola.

However, it is important to prevent excessive resin removal if you are using plasma and permanganate. Also, plasma desmearing enhances the hole quality. This is ideal especially in thick Isola boards.

Applications of Isola FR370HR

The FR4 370HR is widely used in different applications like:

Consumer electronics

Isola 370HR is often used in consumer electronics. This laminate is available in consumer electronics like mobile phones and televisions.

Aerospace and defense

Due to Isola 370HR’s thermal performance, it is ideal for use in this application. The aerospace and defense industry makes use of laminates that are CAF resistant. The Isola FR370HR is one of such.


This is another industry that uses Isola 370HR in producing automobile parts. Isola 370HR has a high glass temperature. Also, this board has great peel strength and flexural strength.

Other applications of this laminate include:

  • Medical devices
  • Industrial and instrumentation
  • Networking and communication systems
  • Computing and peripherals


This article has been able to provide vital information about Isola 370HR. Also, it explained its properties and applications.

    GET A FREE QUOTE PCB Manufacturing & Assembly Service
    File Upload