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LUMISIL® LR 7601/80 A/B

1 of 5 products in this brand
LUMISIL® LR 7601/80 A/B is a liquid silicone rubber from the LUMISIL® LR 7601 series. It is a two-component compound with medium viscosity and fast curing times. The vulcanizates obtained from this material are known for their exceptionally high optical transparency, as well as their outstanding mechanical and electrical properties.

Processing Methods: Injection Molding

End Uses: Automotive Components, Lighting Applications, Lighting Fixtures

Features: Consistent High Quality, Excellent Dimensional Accuracy, Excellent Transparency Properties, Fast Curing, Food Contact Acceptable, Good Electrical Properties, Good Mechanical Properties, Heat Resistance, High Optical Transparency, Low Fogging, Low Shrinkage, Low VOC, Low Volatility, Medium Viscosity, UV Resistant

Tear Strength: 9.0 - 9.0 kN/m

Technical Data Sheet

Knowde Enhanced TDS

Identification & Functionality

Chemical Family
Technologies

Features & Benefits

Ready-to-Use Product Features
Specific Features
  • Food-contact
  • Highly transparent
  • Low volatile
  • Reduced volatile content

Applications & Uses

Plastics & Elastomers Processing Methods
Applications
  • Dairy Applications
  • General Automotive Parts
  • Lighting
  • Molded Parts
Application Details

These grades are particularly suitable for the economical production of large series of injection molded articles with excellent optical transparency. Parts made from LUMISIL® LR 7601/80 A/B can be used for technical applications. These articles are also suitable for use in conjunction with foodstuffs. Postcured parts can be used for food contact applications and are suitable for use under the Recommendation "XV. Silicones" of the BfR and FDA § 177.2600 under observance of any given limitations on extractable and volatile substances. Please note that the product contains low levels (<0.1%) of residual hydocarbons which have to be removed from the finished food contact article.

Processing

  • The A and B components are delivered ready to use in 20 kg pail and 200 kg drum kits. With adequate metering equipment, they can be pumped directly from the original containers into the injection molding machine and mixed by a static mixer.
  • The mixing ratio is 1 : 1. At room temperature, mixtures of A and B components have a pot life of at least three days. For maximum transmission and transparency of injection molded parts, any cross contamination with standard silicones have to be avoided.
  • Therefore, we recommend producing LUMISIL® LR 7601 series with a separate line. Additionally, processing parameters like injection speed, holding pressure have to be adapted to the corresponding viscosities of the LUMISIL® LR 7601 series to guarantee exact filling and de-aeration of cavities.
  • Compared to ELASTOSIL® LR, LUMISIL® LR 7601 series have less mechanical strength. This has to be taken into consideration for the demoulding process, a high shear on parts is not recommended.
  • Demoulding technologies like mushroom ejectors or blowing-off by support of air pressure have been tested successfully. Polygone® 505 is suitable to remove deposits or residues on sensitive mold surfaces.
  • The use of an ultrasonic bath supports a careful cleaning without attacking the surface. It is recommended to use WACKER® Silicon spray in the initial phase of the injection molding process.

Properties

Typical Properties
ValueUnitsTest Method / Conditions
Refractive Index (nD₂₅)approx. 1.41
Cured Properties
ValueUnitsTest Method / Conditions
Density1.05g/cm³DIN EN ISO 1183-1 A
Elongation (at break)70%ISO 37 Type 1
Shore Hardness A78DIN ISO 48-4
Tear Strength9N/mmASTM D 624 B
Tensile Strength10N/mm²ISO 37 Type 1
Uncured Properties
ValueUnitsTest Method / Conditions
Dynamic Viscosity (Shear rate 1 s⁻¹)50000mPa·sDIN EN ISO 3219
Dynamic Viscosity (Shear rate 10 s⁻¹)43000mPa·sDIN EN ISO 3219
Properties
  • The products can be used at temperatures down to -55°C and even above +150°C.
  • The outstanding optical transparency extends over a broad range of the visible spectrum and exceeds the transparency of polycarbonate or polymethylmethacrylate.
  • The refractive index nD₂₅ is in the range of 1.41. LUMISIL® LR 7601/80 A/B is optimized for stateof-the-art requirements of optical parts.
  • In contrast to standard ELASTOSIL® LR grades, the hardness in the product name of LUMISIL® LR 7601/80 A/B reflects the hardness of vulcanized articles in the non-post cured state.
  • Depending on the injection molding parameters, the geometry of the final parts and the post curing conditions, hardness increases after post curing in the range of 5 to 8 points.
Note

Cure conditions: 15 min / 165°C in press.

Regulatory & Compliance

Compliance

LUMISIL® LR 7601/80 A/B is listed in various UL (Underwriter Laboratory) standards including f1 rating, i. e. suitable for outdoor use with respect to exposure to Ultraviolet Light, Water Exposure and Immersion in accordance with UL 746C.

Packaging & Availability

Country Availability
Packaging Type
Regional Availability
  • Africa
  • Asia
  • Europe
  • Latin America
  • Middle East
  • North America
  • Oceania
Packaging Information

This product is available in 20 kg pail and 200 kg drum kits.

Storage & Handling

Storage Information

Once opened, containers should always be resealed after use to prevent the platinum catalyst from being poisoned by amines, sulfur or phosphorus compounds.