TMC-G373H | Transparent Epoxy Molding Compound

Harmonization Code : 3907.30.00.40 | Epoxy Mold Compounds containing by weight more than 70 % silicon dioxide

TMC-G373H | Transparent Epoxy Molding Compound

Main features

Exceptional moldability with waxed formulation
Low moisture absorption even at high temperature and high humidity conditions
Excellent solder resistance for reliability

Product Description

OPTOLINQ TMC-G373H is an optically clear epoxy molding compound specifically designed for the encapsulation of optoelectronic devices. With its high spiral flow, it ensures precise and intricate molding. OPTOLINQ TMC-G373H also offers high moisture resistance, maintaining performance even in high temperature and humidity conditions.

This product stands out with its self-releasing technology and solder resistance for reliability, ensuring good quality and precision in optoelectronic device molding. Overall, OPTOLINQ TMC-G373H is well-suited for the encapsulation of packages that require optical transparency. TMC-G373H is available is custom pellet sizes. Contact us for more information.

Product Key Features

Optimal spiral flow — fills mold completely and uniformly.
Excellent moldability — capable of forming into complex shapes and geometry.
High reliability — allows encapsulated component to function reliably under stress.

Specifications
Additional Information

Technical Specifications

General Properties

Appearance

Appearance
Appearance at room temperature.

White

Refractive index

Refractive index
The refractive index determines how much the path of light is bent, or refracted, when entering a material. It is calculated by taking into account the velocity of light in vacuum compared to the velocity of light in the material.

The refractive index calculation can be affected by the wavelength of light and the temperature of the material. Even though it is usually reported on standard wavelengths it is advised to check the TDS for the precise test parameters.

1.56

Specific Gravity

Specific Gravity
Specific gravity (SG) is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume.

For liquids, the reference substance is almost always water (1), while for gases, it is air (1.18) at room temperature. Specific gravity is unitless.

1.15-1.25

Physical Properties

Spiral Flow @ 175°C

80-220 cm

Chemical Properties

Moisture absorption

0.25 %

Mechanical Properties

Hardness Hardness Hardness is a dimensionless quantity. There is no direct relationship between measurements in one scale and their equivalent in another scale or another hardness test.
Durometer (Shore D)	Min 80

Flexural Modulus
Flexural Modulus @ 25°C	2600-3400 N/mm2

Flexural Strength
Flexural Strength @ 25°C Flexural Strength @ 25°C Flexural strength, also known as modulus of rupture, or bend strength, or transverse rupture strength is a material property, defined as the stress in a material just before it yields in a flexure test. This is the flexural strength tested at Room Temperature, 25°C	110 N/mm2

Molded Shrinkage

1.5 %

Electrical Properties

Visible Light Transmission

90 %

Thermal Properties

Coefficient of Thermal Expansion (CTE) Coefficient of Thermal Expansion (CTE) CTE (Coefficient of thermal expansion) is a material property that is indicative of the extent to which a material expands with a change in temperature. This can be a change in length, area or volume, depending on the material. Knowing the CTE of the layers is helpful in analyzing stresses that might occur when a system consists of an adhesive plus some other solid component.
Coefficient of Thermal Expansion (CTE), α1 Coefficient of Thermal Expansion (CTE), α1 CTE α1 (alpha 1) is the slope of the Coefficient of thermal expansion in a temperature range below the Glass transition temperature (Tg). It explains how much a material will expand until it reaches Tg.	60 ppm/°C
Coefficient of Thermal Expansion (CTE), α2 Coefficient of Thermal Expansion (CTE), α2 CTE α2 (alpha 2) is the slope of the Coefficient of thermal expansion in a temperature range above the Glass transition temperature (Tg). It explains the extent to which a material will expand after it passes Tg.	80 ppm/°C

Gel Time Gel Time Gel time is the time it takes for a material to reach such a high viscosity (gel like) that it is no longer workable. It is usually measured for different temperature conditions and even though it does not refer to full cure it is advisable to never move or manipulate the material after it reached its gel time since it can lose its desired end properties.
Gel time @ 150°C	25-50 Sec

Glass Transition Temperature (Tg)

Glass Transition Temperature (Tg)
The glass transition temperature for organic adhesives is a temperature region where the polymers change from glassy and brittle to soft and rubbery. Increasing the temperature further continues the softening process as the viscosity drops too. Temperatures between the glass transition temperature and below the decomposition point of the adhesive are the best region for bonding.

The glass-transition temperature Tg of a material characterizes the range of temperatures over which this glass transition occurs.

100 °C

Curing Conditions

Curing Schedule Curing Schedule Curing schedule is the time and temperature required for a mixed material to fully cure. While this applies to materials that cure with heat, there are also other materials that can be cured with UV. Even though some materials can cure on ambient temperatures, others will require elevated temperature conditions to properly cure. There are various curing schedules depending on the material type and application. For heat curing, the most common ones are Snap cure, Low temperature cure, Step cure and Staged cure. Recommended cure type, schedule, time and temperature can always be found on the Technical data sheets.
Cure Time	2.5-4 min
Mold Temperature	160 °C
Preheat Temperature	75-95 °C

Post Mold Cure
Post Mold Cure @ 175°C / 347°F	3-4 hrs

Transfer Pressure

0.31-0.41 Kg/mm2

Transfer Time

40-60 s

Additional Information

Processing Instructions

Before use, allow TMC-G373H to reach room temperature (20±5 °C, 40±15% RH) for a minimum of 24 hours for larger pellets and 12 hours for smaller ones, ensuring the bag remains unopened to prevent moisture contamination.
For TMC-G373H in larger sizes, preheating can be performed using standard RF equipment. Preheating must be done slowly to achieve uniform temperature.
Prior to molding with TMC-G373H or any new material, the mold should be cleaned thoroughly. To prepare the mold, the initial three shots should be cured for 5–10 minutes. After this initial preparation period, you can reduce the curing time to a level that provides sufficient hot hardness for effective release.

Storage and Handling

OPTOLINQ TMC-G373H is available in pressed pellets in a wide range of sizes to meet specific customer needs. To ensure product integrity, keep it away from oxidizing materials. For long-term storage, maintain a cold environment, ideally at –10 °C or lower. The shelf life under this condition is 6 months.

The technical information presented in this document is provided for reference only and does not constitute a guarantee of specific properties or performance. Actual results may vary depending on individual conditions and application methods. Users are strongly advised to perform their own testing and validation to determine suitability for their intended use and compliance with relevant regulations.