Silicone Addition Yellow 25 Set – Soft Addition Mold Rubber for Molds & Prototypes
Silicone Addition Yellow 25 Set – Soft Addition Mold Rubber for Molds & Prototypes
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Ordered and paid on a working day: usually ships the same day
Delivery to Netherlands: usually within 1 working day
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Premium Soft Addition Mold Rubber for Professional Mold and Prototype Applications
Silicone Addition Yellow 25 is a pourable, addition-curing (platinum) RTV-2 mold rubber that cures at room temperature. Thanks to added silicone oil, this rubber is softer and more free-flowing than our Green 30: the hardness is Shore A 22 and the viscosity 6,000 mPa·s. The components are mixed 1:1 by weight. The pot life is 60 minutes, the mold can be demolded after 6 hours at 20 °C and reaches full strength after 1 day. The yellow rubber has a tensile strength of 3.9 N/mm² and is suitable for molds with undercuts and for casting epoxy, polyurethane and polyester.
Key Benefits
- Hardness Shore A 22 – soft rubber from which models with undercuts are easy to demold.
- Viscosity 6,000 mPa·s – flows easily around fine details and degasses well.
- Tensile strength 3.9 N/mm² – sufficient strength for repeated demolding.
- Mixing ratio 1:1 by weight – easy to weigh and process.
- Pot life 60 minutes – ample time to pour and degas carefully.
- Full strength after 1 day – quickly ready for the first casts.
Typical Applications
- Molds of models with undercuts.
- Molds for casting resins such as epoxy, polyurethane and polyester.
- Soft, flexible molds for fine details.
- Prototypes and decorative pieces.
- Molds for ornaments and jewelry.
Processing Instructions
- Stir component A and component B separately and thoroughly first.
- Weigh A and B in a 1:1 ratio by weight. Only use components with the same lot number.
- Mix slowly and carefully in a figure-8 motion, without whipping in air.
- Preferably degas the mixture in a vacuum chamber immediately after mixing.
- Pour within the 60-minute pot life.
- Allow the mold to cure for at least 6 hours at room temperature. A slight temperature increase speeds up curing; air bubbles then have less time to escape.
If you want to apply the rubber with a spatula instead of pouring it, add Silicone Thixo A (not Thixo C).
Good to Know: Silicone Oil
This mold rubber contains silicone oil. It does not crosslink and can bleed out slightly over time, which may cause a greasy layer on the mold surface and slight shrinkage. Clean cast parts thoroughly before painting or bonding them.
Important Warning: Inhibition of Addition Silicones
This is an addition-curing silicone (platinum cure). Curing can be disrupted by sulfur, nitrogen, amine compounds and metal salts. These substances are found in, among others, latex gloves, some modelling clays, paints and adhesives, condensation silicones, 1-component silicone sealant, natural rubber and certain 3D printing materials. If in doubt, run a small test first or apply a separating layer of polyvinyl alcohol.
Silicones and More, specialist in high-quality mold rubbers and casting materials for professional makers.
Professional Support
Need a firmer mold with higher tear strength and no oil? Take a look at Silicone Addition Green 30. Unsure which mold rubber best suits your application? Contact us at info@siliconesandmore.com, we are happy to help.
Product Properties
- Hardness22Shore AHardness of the silicone material
- ColorYellowColor of the finished product
- Viscosity6000mPa·sViscosity of the uncured silicone
- Density1.05g/cm³Density of the cured material
- Mix ratio1:1Mixing ratio A : B
- Tensile strength3.9MPaMaximum tensile force before breaking
- Pot life60minutesWorking time after mixing
- Cure time360minutesTime until full cure
Component Properties
- Color AYellowColor of component A
- Color BWhiteColor of component B
Application
- Use caseSoft moulds with undercuts, moulds for casting resins and prototypesIntended use
- Silicone type["Addition curing","RTV-2"]Type of silicone or polymer
- Cure speedNormalHow quickly the material can be demoulded
- Cure conditionRoom temperatureCondition under which the material cures
Safety Information
This mold rubber is not classified as a hazardous mixture under the CLP Regulation and carries no hazard pictograms or H statements. Component B can form hydrogen gas on contact with water, alcohols, acids, bases, amines or metal salts; keep the product dry and away from ignition sources. When heated above approx. 150 °C, a small amount of formaldehyde may be released. Wear nitrile gloves and safety glasses during processing and ensure good ventilation. Respiratory protection is not required under normal use, only where mist or spray forms (FFP1). Consult the safety data sheets for component A and component B for complete information on storage, disposal and emergency measures.| Safety Pictograms | Safety Data Sheets (SDS) |
|---|---|
Required protection (ISO 7010)
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Frequently asked questions
What is the delivery time for my order?
Orders placed and paid on working days are in most cases shipped the same day. Weekend orders are processed on the next working day.
Indicative delivery times: Netherlands usually within 1 working day, Belgium and Germany typically 1–2 working days, other countries depending on destination and carrier. These are guidelines, not guarantees: peak periods, public holidays or carrier delays can have an effect.
What is the return policy?
You have 30 days to return after receipt. Email info@siliconesandmore.com within 30 days of delivery with your name and order number. The full conditions are in our return policy.
How can I track my order?
As soon as your order has shipped, you'll receive a track & trace code by email. It can take up to 24 hours before the code is active.
I have a problem with my order – how do I reach you?
Contact us via our contact page or email info@siliconesandmore.com. We're happy to help you quickly.
Can I order as a business?
Yes. Apply for a business account; we review your application within 3 working days. After that you order while logged in and pay on invoice, with payment terms of 14 days after delivery.
EU businesses outside the Netherlands with a valid VAT number order with VAT reverse-charged (0%, intra-community supply). The VAT number is stored in your business account; it cannot be added to an order after it has been placed.