Silicone Rubber TECHNICAL INFORMATION

Omni Silicone Rubber TECHNICAL INFORMATION

AMAZING

AMAZING Introduction

Omni silicone rubbers have been formulated using only the highest Omni quality raw materials sourced from many different countries; this ensures that Omni rubber has the highest Silicone Rubber performance characteristics. The Omni range has been developed in our Contents own laboratory where we have the very latest hi tech equipment for measuring all of the 1 Benefits of using Silicone Rubber critical properties of both the raw materials and finished products. 2 The Omni Silicone Rubber range Every batch of Omni silicone rubber we - Omni L.C. (Low Cost) manufacture ourselves, they are all tested - Omni – Sil before being allowed to be despatched to our - Omni L.T. (Low Temperature) customers as required by our ISO 9001 quality assurance system. 3 Specialist Mold Rubbers Our hi tech equipment allows us to test and 4 Preparing a Master Model control the following characteristics to their breaking point... 5 Packing the Mold Frame • Tear strength 6 Vulcanizing the Packed Mold Frame • Tensile strength

7 Mold Cutting • Elongation

8 Producing a mold using Separation Cream and Locating Pins

9 Calibrating the Vulcanizer

10 Storage & Shelf Life

11 Silicone Rubber Problem Solving

12 Silicone Rubber Material Safety Data Sheet

13 Mold Separation Cream Material Safety Data Sheet 1 The Benefits of using Omni Silicone Rubber

Silicone rubber use in all of the discerning jewelry factories has grown dramatically over the past 5 years; silicone rubber is at the forefront of jewelry casting now and in the future.

Omni silicone rubbers provide far better surfaces on wax patterns than natural rubber, they are comparable in cost but offer a much higher performance. Our rubber is easy to pack, vulcanize and cut; all of these attributes combine to make Omni Silicone Rubber the obvious choice.

• Easier to pack the mold when compared to natural rubber

• Glass like finish on the wax pattern, producing a better cast surface, therefore less finishing and polishing needed

• Exceptional detail reproduction

• Self lubricating, no need for sprays or talc

• Easier to cut the mold

• Greater flexibility particularly where intricate designs, cores or plugs are required

• Can be used along with locator pins and separation cream

• Produces a tighter seal and therefore reduces wax flashing

• L.T. can be used to produce molds directly from RP/SLR patterns 2

Omni Soft Omni HTV

Silicone Rubber Vulcanization Temp 165 - 175ºC 330 - 347ºF Range Shore A Hardness 28 - 30

Omni Omni Sil L.C. HTV HTV

Vulcanization Temp 165 - 175ºC Vulcanization Temp 165 - 175ºC 330 - 347ºF 330 - 347ºF Shore A Hardness 38 - 40 Shore A Hardness 48 - 50

Omni Speedi L.T. - Cure LTV QCV

Vulcanization Temp 72 - 82ºC Vulcanization Temp 85 - 95ºC 161 - 180ºF 185 - 203ºF Shore A Hardness 38 - 40 Shore A Hardness 38 - 40 3 Specialist Mold Rubbers

Omni L.T. Because direct casting of a RP/SLR model is extremely difficult most all jewelry manufacturers now produce molds directly from the resin model and from the mold create their wax patterns to cast.

Omni L.T. (Low Temperature) allows you to produce a mold directly from the RP/SLR pattern because it vulcanizes at between 162 and180°f (72 - 82°c) and does not therefore distort the pattern during vulcanization.

Omni L.T. allows for an average sized mold to be packed, vulcanized, cut and ready to inject within 2 hours.

Omni Speedi – Cure

“Time is money” in particular in a jeweller’s work place Mold Size Quick Cure STD HTV Cure where a one-off casting is required instantly. Omni 12mm (1/2”) 10 mins 30 mins “Speedi – Cure” can help save precious time and a ¾” (20 mm) mold can be produced in 45 minutes. 19mm (3/4”) 15 mins 45 mins 25mm (1”) 20 mins 60 mins Omni “Speedi – Cure” has exactly the same mechanical properties as Omni – Sil and produces the exact same quality of pattern, it simply allows you to move faster.

Using this type of rubber requires the vulcanizer to be calibrated regularly and at the correct set temperature. 4 Preparing a Master Model

To ensure the best results Masters should be cleaned before producing the rubber mold, the best method for this is to use the ultrasonic cleaning process.

To achieve the best surface it is advised to rhodium plate masters, this will fill in any imperfections and give a perfect surface. After plating the master should be cleaned, again using an ultrasonic.

Where brass is used to produce the master, it should be plated as brass may well react with the rubber.

It is a fact that more time spent on perfecting the Master Pattern will save time on finishing of the casting.

MASTER MODEL

Is it made out of brass?

Yes No

Plate to stop Clean Plate mold reaction Make mold Clean Clean Make mold Make mold 5 Packing the Mold Frame

Please note that the mold frames used for silicone rubber should not be used for Correctly Packed natural rubber, they are incompatible.

Pack the mold frame base ensuring that all of the cavity is completely filled. The rubber in the mold Under-Packed frame should be slightly overfilled and be convex. This will ensure that the rubber flows completely around the master during vulcanization.

If the mold is not completely packed they will almost certainly result in bubbles inside the cured mold.

It is possible to use both Omni L.C. and Omni – Sil in the same mold, this method is often used where the pattern being created is highly detailed or intricate but the size requires a firm exterior. This process also leads to a longer life of the mold.

Please DO NOT use Omni L.T. for this process it is not compatible with Omni L.C. or Omni – Sil. 6 Vulcanizing the packed Mold Frame

It is advisable to turn the vulcanizer on at the required temperature 30 minutes before use; this will ensure that will have sufficient time at the correct temperature to achieve full vulcanization.

For best results you should regularly calibrate your vulcanizer, the read out temperature can be as much as 60°f (15°c) below the required temperature which will result in an under cured mold.

Defects where the mold is under cured are: • Bubbles in the Mold • Sticky Molds • Low Shore A Hardness • Poor Memory • Poor Tear Strength

If you experience any of these defects in your molds we suggest that you check the calibration of your vulcanizer. 7 Mold Cutting

There are so many different methods of mold cutting, many passed down from father to son and so on, cutting the rubber mold is by far the most effective way rather than using separation cream and locating pins.

Cutting allows for a far more intricate wax pattern to be injected where cores, undercuts and spirals are required.

When producing the rubber mold, and in particular where silicone rubber is used because of the high gloss surface of the rubber, the use of “Air Venting” is advisable. The vents are important to allow the flow of air out of the mold as the wax is injected. Venting also reduces the chance of wax flashing in the mold during injection. 8 Producing a mold using Separation Cream and Locating Pins

This method is used generally speaking, where the pattern to be injected is very simple.

1 The mold is produced by packing the base of the frame with silicone rubber, placing the master onto the base and pressing it in. A thin layer of separation cream is applied over the surface (ensuring that the master is not covered)

2 Place the locating pins into each corner of the rubber mold.

3 Proceed to pack the remainder of the mold tightly.

4 Continue to vulcanize the mold at the recommended temperature and time as recommended.

5 Once the vulcanizing is completed remove the mold frame and allow it to cool, when cooled remove the mold from the frame and it will easily part allowing removal of the master. The mold is now ready to use. 9 Calibrating the Vulcanizer

Regular calibration of the Vulcanizer is very important in ensuring that the rubber is fully cured, our recommendation would be for the re calibration every six months. For this you will need a thermometer with a “K” type thermocouple and a small block of wood, see instructions below.

Where the mold is not fully cured you may well see the following mold problems... • Bubbles in the Mold • Sticky Molds • Low Tear Strength • Low Shore A Hardness. • Poor Mold Memory

Steps to Calibrate the Vulcanizer

1 Close the vulcanizer platens, turn it on, set to the vulcanizing temperature (330°f - 165°c). Allow to stand for 30 minutes to achieve temperature.

2 Open the platens and place the wood in position, put the thermocouple on top of the wood and close the platens.

3 Leave to stabilize for 10 minutes then take the temperature reading; compare it to the desired temperature.

4 Where the temperature is too high or too low reduce or increase it on the dial and allow to settle, then take a second reading using the same method, continue until the two readings are in unison and correct.

5 Repeat the same exercise for the bottom platen The readings on the vulcanizer and thermocouple should not differ by more than +/- 5% 10 Storage & Shelf Life

Silicone Rubber contains catalysts which HTV Shelf Life - Months are temperature activating, therefore it is 14

important that the rubber is stored away 12

from direct sunlight and at a temperature 10

below 72°F /22°C to obtain the maximum 8 shelf life. Months 6

4 From the graphs illustrated you will see that where the suggested storage is followed the life of the rubber 2 will be more than 1 year, however, if it is stored, for 0 example, at 100°f/40°c then the life is only 6 months. 25 30 35 40 45 50 Storage Temperature °C

HTV Shelf Life - Months LTV/QCV Shelf Life - Months 14 14

12 12

10 10

8 8 Months 6 Months 6

4 4

2 2

0 0 25 30 35 40 45 50 25 30 35 40 45 50 Storage Temperature °C Storage Temperature °C

LTV/QCV Shelf Life - Months 14

Months 6

0 25 30 35 40 45 50 Storage Temperature °C 11 Problem Solving Silicone Rubber

I have air bubbles in my mold? My molds are sticking to the mold plates? - The mold is under packed and is not achieving - Your molds are not fully vulcanized, refer to sufficient compression during vulcanization. instructions on the packaging. - The mold vulcanization temperature is too high, - Use non-stick mold plates. therefore not allowing the air bubbles to flow out of the rubber during the vulcanization process. The rubber is not filling all the mold cavities and - The mold has been under-heated or cured for undercuts? insufficient time and therefore not completed the - The mold is under-packed. curing process. - Ensure mold is fully packed and cavities are pre- - Ensure mold frame is correctly packed, refer to packed with silicone putty before inserting into the instructions on the packaging. mold. See pages 15 and 16. - Ensure vulcanizing temperature is not too high and My molds are too soft (or sticky) when compared to vulcanizer is calibrated correctly. the manufacturer’s specification? - The mold has been under-cured, please see below for My uncured rubber is very hard? solutions. - Your rubber has been stored at a high temperature - Ensure you are vulcanizing the mold for the correct for a period of time exceeding our recommendations. amount of time for the thickness of mold. See page 10. - Ensure you are using the correct vulcanization temperatures. My molds are not filling with wax fully? - Ensure your vulcanizer is calibrated. - Ensure air vents are cut and there is an adequate number of them. The Tear Strength of my molds is low? - Increase injection temperature of wax. - The mold has been under cured, please see below for - Increase injection pressure. solutions. - Ensure you are leaving the mold for the correct amount of time for the thickness of mold. - Ensure you are using the correct vulcanization temperatures. - Ensure your vulcanizer is calibrated.

My molds are sticky? - Your vulcanization temperature is too low. - Ensure you are using the correct vulcanization temperatures. - Ensure your vulcanizer is heated to the correct temperature in comparison to what it is set at. - Calibrate your vulcanizer. 12 Silicone Rubber Material Safety Data Sheet

1. IDENTIFICATION OF SUBSTANCE & COMPANY INFORMATION Respiratory: The use of a dust mask or equivalent to EN149 Category Silicone Rubber FFP2S, and the provision of dust extraction/ventilation where dust is SRS generated is recommended. Spencroft Road, Newcastle-under-Lyme Hands: Gloves. Staffordshire, ST5 9JE Eyes: Goggles. Email: [email protected] Skin: General protective overalls. Emergency Telephone No: +44 (0)1782 663633 General: Use good personal hygiene.

2. HAZARDS IDENTIFICATION 9. PHYSICAL AND CHEMICAL PROPERTIES This mixture has been evaluated as a whole. All ingredients are bound Appearance & Odour: Thin pliable sheet or roll, odourless in a polymer matrix and potential for hazardous exposure as shipped is pH: Not Applicable minimal. Boiling Point: Not Applicable According to Regulation (EC) No. 1272/2008 (CLP) Melting Point: Not Applicable Hazard Pictogram(s): N/A Relative Density: 1.0 – 1.5g/cm3 (Estimated value) Signal Word: N/A Solubility in Water: Insoluble Hazard Statements): N/A Particle Size: Not Applicable Precautionary Statement(s): N/A Classification – Regulation EC 1272/2008 (CLP): N/A 10. STABILITY AND REACTIVITY This material is considered to be stable. According to Directive 67/548/EEC or 1999/45/EC Hazard Symbol(s): N/A 11. TOXICOLOGY INFORMATION Risk Phrase(s): N/A May cause skin irritation leading to dermatitis. At temperatures between Safety Phrase(s): N/A 150˚C and 180˚C rubber fumes are given off.

3. COMPOSITION INFORMATION 12. ECOLOGICAL INFORMATION A proprietory mixture containing silicone rubber, mineral fillers and According to our experience, no adverse effects are to be expected. pigments. 13. DISPOSAL INFORMATION 4. FIRST AID MEASURES As required by local regulations. Where incineration is used, the Routes of Entry: incinerator used must be specifically designed to give complete Eye: Wash with copious amounts of water. If irritation persists, seek combustion of the gasses and fumes produced. medical advice. Skin: Wash with soap and water. Use hand lotion. 14. TRANSPORT INFORMATION Inhalation: Move exposed person to fresh air immediately. No special precautions are required. This product is not classified as Ingestion: Non toxic. No special treatment. dangerous for conveyance.

5. FIRE FIGHTING MEASURES 15. REGULATORY INFORMATION Flash Point: <300˚C This product is not classified under the Chemicals (Hazard Information Flammability: Flammable and Packaging) Regulations 1993 (CHIP). Explosive Properties: Unknown Extinguishing Media: Any type 16. OTHER INFORMATION EH40/2005 Workplace Exposure Limits 6. ACCIDENTAL RELEASE MEASURES EH44/1997 Dust: General Principles of Protection Scoop or shovel material and return to original container. HSG 37 An introduction to Local Exhaust Ventilation

7. HANDLING AND STORAGE Caution: Nitrosamines – (considered to be possible human carcinogens) Such information given on this Material Safety Data Sheet is to the best may be formed during processing of rubber compounds. Mixing or of the company’s knowledge and belief, accurate and reliable as of the contacting this product with nitrates or nitrites, as in salt bath curing, date indicated. However, no representation, warranty or guarantee is may produce hazardous levels of volatile nitrosamines. made as to its accuracy, reliability or completeness. Rubber compounds contain materials that may cause skin irritation leading to dermatitis in sensitive persons. It is the user’s responsibility to satisfy itself as to the suitability and Store under dry conditions and away from direct sunlight. completeness of such information for their own particular use. DATE OF Keep containers closed. ISSUE: December 2011

8. EXPOSURE CONTROLS & PERSONAL PROTECTION Some fumes may be released upon heating (150˚C) or vulcanization and the end user must take the necessary precautions (mechanical ventilation, respirator program etc…) to protect their employees from exposure. 13 Mold Separation Cream Material Safety Data Sheet

1. IDENTIFICATION OF SUBSTANCE & COMPANY INFORMATION 9. PHYSICAL AND CHEMICAL PROPERTIES Mold Separation Cream Appearance & Odour: White cream, lotion or paste with a slight alcohol SRS odour. Spencroft Road, Newcastle-under-Lyme pH: Not Applicable Staffordshire, ST5 9JE Boiling Point: Unknown Email: [email protected] Melting Point: Unknown Emergency Telephone No: +44 (0)1782 663633 Relative Density: Not Applicable Solubility in Water: Slight 2. HAZARDS IDENTIFICATION Particle Size: Not Applicable This product contains a form of crystalline silica, inhalation of large amounts of which is considered to be hazardous. However only small 10. STABILITY AND REACTIVITY amounts of this silica is present in this compound and is bound in a This material is considered stable under normal temperature conditions. cream, such inhalation is considered unlikely. We do not consider this Avoid excessive heat for prolonged periods of time, will not polymerise. product to be hazardous as no dust is present or generated during normal use. 11. TOXICOLOGY INFORMATION According to Regulation (EC) No. 1272/2008 (CLP) Ingestion: None Hazard Pictogram(s): N/A Skin: None Signal Word: N/A Eyes: May cause slight irritation Hazard Statements): N/A Precautionary Statement(s): N/A 12. ECOLOGICAL INFORMATION Classification – Regulation EC 1272/2008 (CLP): N/A According to our experience, no adverse effects are to be expected.

According to Directive 67/548/EEC or 1999/45/EC 13. DISPOSAL INFORMATION Hazard Symbol(s): N/A As required by local regulations. Risk Phrase(s): N/A Safety Phrase(s): N/A 14. TRANSPORT INFORMATION No special precautions are required. This product is not classified as 3. COMPOSITION INFORMATION dangerous for conveyance. A propriety mixture which is not classified as being hazardous 15. REGULATORY INFORMATION 4. FIRST AID MEASURES This product is not classified under the Chemicals (Hazard Information Routes of Entry: and Packaging) Regulations 1993 (CHIP). Eye: Wash with water immediately for 15 minutes, seek medical advice. Skin: Wash with soap and water. 16. OTHER INFORMATION Inhalation: None All personnel using/handling this product should be trained in the proper Ingestion: Do not induce vomiting unless so directed by a doctor. Seek handling, storage, control measures and protective equipment. medical advice

5. FIRE FIGHTING MEASURES Such information given on this Material Safety Data Sheet is to the best Flash Point: 160˚C of the company’s knowledge and belief, accurate and reliable as of the Flammability: N/A date indicated. However, no representation, warranty or guarantee is Explosive Properties: N/A made as to its accuracy, reliability or completeness. Extinguishing Media: Any type It is the user’s responsibility to satisfy itself as to the suitability and 6. ACCIDENTAL RELEASE MEASURES completeness of such information for their own particular use. DATE OF Contain the spill or leak. Scrape up with cardboard or cloth and place in ISSUE: December 2011 container.

7. HANDLING AND STORAGE Handling: Wash hands after handling. Storage: Store in a cool place. Keep away from heat and flames.

8. EXPOSURE CONTROLS & PERSONAL PROTECTION Respiratory: None Hands: None Eyes: Safety Glasses Skin: None General: Use good personal hygiene. www.whipmixjewelryinvestment.com