What is Liquid Silicone Rubber(LSR)?

Silicone rubber is composite materials, such as RTV Silicone (Room-Temperature-Vulcanizing silicone), the high temperature vulcanized silicone rubber (HTV), High Consistency Rubber(HCR) and Liquid Silicone Rubber(LSR).

Properties of liquid silicone rubber(LSR)

1.High temp resistance

The outstanding property of matter in the condition of high temperature(over 200ºC)for a long time, endure short time exposure up to 350ºC

2.Low temp resistance

Outstanding flexibility in the condition of low temperature(-70ºC). possible to use low-temperature material in the condition of ultralow temperature(under-100ºC)

3.Low compression set

Possible to use application for such as seal ring and gasket due to outstanding compressed permanent strain(strong at shrink and distortion by compress)

4.Chemical resistance

Outstanding oil resistance, solvent resistance, and chemical resistance. Aniline, Alcohol or Alkali cannot be invaded.

5.Electric property

Having hydrophobic for water and excellent electric insulation. No decline of performance by exposure to water.


LSR injection molding advantage

Complex geometries. Provide excellent expressivity of ultra-thin and complicated shape thanks to the low viscosity of LSR.

Automation. Implement automation of the entire process from Dosing to De-molding in contrast with other labor-intensive rubber injection.

Improved safety. Build a safe production area by an unmanned automation system.

Fast cycle. Improve productivity with innovative cycle time by ‘sec.’ unit compared to ‘min.’ unit cycle time of compression and transfer molding

Material preparation. Prevent contamination and faulty mix of material and save time and labor by eliminating the preparation processes like mixing material.


Liquid Silicone Rubber(LSR) application.


liquid silicone rubber automatic

Wide Applicable Temperature Range: -50~200ºC (-58 ~392ºF)

Maintain of performance required as automotive part under harsh environment.

Stable physical property, Insulation, Weatherability Permanent compression ratio under the wide temperature range

Flexible joint movement and excellent sealing performance.

Silicone reduces noise by creaking, protect and improve the appearance of exterior parts and keep interior parts robustly.



LED is a lighting part made by a compound semiconductor which lights with an electric current.

LSR is applied for encapsulants which protect chip & wire from humidity and external shock. LED package of infrared and visible was used with epoxy encapsulants, silicone encapsulants applied for white and high brightness LED package required for excellent heat, light, yellowing-resisting property.

Why the applicant LSR?

Prevention of light output decrease. Improvement of quality of high performance LED extension of lift time.

Elastomer series. Easy filling for complex shaped parts cracks prevention against stress.

Thermal resistance up to 200ºC. High bright white & blue LED prevents yellowing by UV.

liquid silicone rubber led



liquid silicone rubber for medical

Excellent heat-resisting property. Easy sterilization and autoclave available, no acceleration of bacterial multiplication.

Flexible Silicone Material. No harmful to the patient because it does not contain Phthalate and fabricated additives.

No skin trouble and allergy compared to other lubber products because it is a dwelling type. Widely used in the medical industry like a urethral catheter, especially an oxygen mask, diving equipment.



How about “Sealing”?

Ultra-low compression set. Achievement of 15% permanent compression ratio without curing after 22hours at 175ºC.

Wide Range of Hardness. Possible set up a wide range of hardness and achieve the optimized sealing performance.

Excellent media resistance. Superior mass resistibility and strong for corrosion and chemical parts.


How about “Lighting”?

94% Transmission. Approximately 94% uniform transmission over the wide range of visible and invisible light.

<1% Haze. Hazy degree less than 1% after passing through the lens and ensure clarity.

Abbe number. In physics and optics. Abbe number is a measure of the material’s dispersion in relation to the refractive index. The higher abbe number means less light scattering and chromatic aberration. As much more clear reflection.

Durability. High-temperature resistance even above 150ºC. UV light resistance. Micro-crack resistance.

Design Freedom. LSR minimizes stress on complex microstructures based on high flowability. Direct gating through cool runner is available to product required for high tolerance.


LSR application examples


Wire seal. It could meet the performance and quality required as the automotive part in a wide temperature range from -50~200ºC(-58~392ºF). It makes joint flexible movement and excellent sealing such as O-ring, Wire seal, Gasket, etc.


Pacifier. Excellent heat resistance makes hot water disinfection possible. Harmless to humans without bisphenol-A soft touch like mother’s makes baby snug.

LED Packaging

Led lens. Excellent thermal, light and yellowing resistance. Suitable for high luminance LED applied to the lighting. Automotive, mobile, monitor, TV, Display.

Kitchen Appliances

High thermal and fouling resistance.Ideal for home applications because of harmless to humans.


Mask. Soft-touch brings excellent wearing sensation. Suitable in a harsh working environment like welding, painting and dealing chemicals without transformation.


Menstrual cup. Environmentally friendly material medical grade silicone. No detection of endocrine-disrupting chemicals and chemical substances.

Compression Molding

Rubber Compression molding

Compression molding is one form of molded silicone rubber parts. Compressing preformed silicone rubber in a mold with a press during the compression process, Silicone rubber is forced into the mold cavity to form the final product during this process, any excess rubber is pushed into the flash and trim gate allowing easy cleanup once the rubber is set.

Compression molding works best for medium hardness compounds in low volume production. Silicone rubber can be difficult to insert into more complex mold designs. And Soft and Hard silicone rubber compounds don’t do well in the compression molding process.

But Silicone rubber compression molding offers advantages over other methods

  • Cost-effective Tooling
  • Maximized cavity count
  • The short set-up time that saves on short production runs
  • Economical process for medium precision
  • the least amount of waste in comparison to other molded rubber processes. 

Compression molding can be a cost-effective solution when:

  • Having silicone rubber industries manufacture the Tooling.
  • the cross-section of the part is very large and requires a long cure time.

Compression molding is used for anything from simple silicone rubber o ring to the most complex silicone parts.

If compression molding isn’t the best fit for your project, Ukong can offer a variety of other molded silicone rubber products through injection or transfer molding.


Injection Molding

Liquid silicone injection molding

Injection molding process involves rapidly injecting an exact amount of Silicone rubber from a tube or cylinder into a closed heated mold, the injection press closes the heated mold and applies pressure to keep the mold closed during the injection and curing cycles, the screw then injects the silicone rubber through the nozzle into the mold. the silicon rubber travels through the mold via a system of runners and sprues and finally enters the mold cavities through a gate, it then fills and packs the cavities to form the desired part rubber.

Injection molding offers economical advantages including:

  • short molding cycle
  • Lower unit cost
  • high dimensional tolerances
  • An absence of flash
  • little scrap or waste.

If you’re interested in what Ukong can do for your company email us at


Transfer Molding

Rubber transfer molding

Transfer molding combines the advantages of injection molding with the ease of compression molding. the process of transfer molding involves placing a rubber and a chamber at the top of the mold and then pushing through sprues into a heated mold.

Transfer molding offers several advantages over other methods,

  • shorter production cycles
  • maintains close dimensional tolerances than compression molding
  • provides uniformity to the molded products
  • fast mode setup.



The Shore Durometer A Scale is an industry-standard for measuring flexible rubber materials, and this is really important in choosing the right mold material for a particular job or in the case of choosing a casting material that might be a flexible casting material.


To get started we need to first understand what is durometer or what the shore A durometer is. The A durometer is both the measurement and the gauge used to measure soft elastomer and what this is a gauge that has a little pin that sticks out at the bottom, and when that pin is pushed in flush with the base of the gauge that’s what gives you the reading on a given flexible material, so depending on how hard how far that pin pushed into the base is determines the hardness or softness of a material. The Shore D Scale measures the hardness of hard rubbers and hard plastics.

Below is a table of shore A hardness scales.

durometer scale

The A scale measures from a zero all the way up to a ninety-five, this is the most common scale for mold making materials. Most flexible rubber materials that you’ll be used for mold making or casting will be found somewhere on the Shore A scale. the low end of the scale a 0 or a 10 is going to be very soft, a high number will be very hard. In fact, the A scale a low number is going to feel very soft almost like human skin, a hard number would feel almost like hard plastic. Most of the materials we use for molding and casting are the lower end of the scale all the way up to the medium. A zero would be about like warm chewing gum, a 10 like human skin, a 50 to 60 would be about like a car tire and a roller skate wheel or a hard hat is going to measure around a 95. 

What materials and durometer can be compression and injection molded? How do you determine what durometer of material to use?

Please remember that the durometer selected will be based on the requirements of your project.

UKONG can help you to choose the material shore hardness for your next silicone project.



kids swim cap

Putting on swim caps can be painful if not done carefully! And you wouldn’t want to cause damage to the fragile hairline, so here are our tips.

Protect your little one’s hair by using a swim cap. Fitting the cap need not be difficult. Tie long hair back, start with your little one facing away from you. Place hands in the cap and stretch out. lower over their forehead first, slide hands back and down their scalp, make sure the ears tucked away. A child over 3 can help by holding the front of the cap, slide your fingers underneath to tuck loose hair in and make it comfortable. Now they are set to enjoy the water!

When it comes to taking the swim cap off, peel back from the forehead and slide off their back head.

suction plate for baby

Our silicone baby plate is awesomely gripping and helps steady where they should be. These are top tips to show you how to make sure your short plates and bowls don’t budge.

Tip 1. Use a flat smooth surface on maximum suction.

Tip 2. Make sure the surface you’re going to use your suction tableware on is clean and dry.

Tip 3. The maximum suction the silicone plate press down on the center of the plate with a fork or spoon. This is to remove any trapped air underneath to help ensure a complete seal for added suction for maximum suction, avoid using baby wipes on your surface as this can leave a residue that can affect the suction.

Tip 4. Please check that your silicone tableware doesn’t budge, add your little ones food and watch them enjoy controlling their mealtime.

How to fold your menstrual cup?

There are different ways that you can fold your menstrual cup. Some methods work better for some bodies and others work better for others. It just depends on your body.

Each fold has it’s own pros and cons but it basically comes down to how small the fold makes the cup and how easily it will pop open once inserted.

menstrual cup fold

Punch down fold. It’s called this because you take your index finger & Push the top down. To the middle of the bottom of the period cup. When you do this it creates a very small insertion point which is quite close to the size of a tampon. It’s also one that we recommend if you’re using a softer cup that has difficulty opening inside. So what you can do is push the base, once it’s inside, and use that to give you a pop at the rim.


menstrual cup C fold

 C fold. This is very popular & often recommended. You’ll see this in lots of instruction manuals for your new menstrual cup. Take your index finger & push down on the side of the lady cup until one side is touching the other. And then squeeze it together. This is going to make that “C” or “U” shape. This is a very popular fold because you can do it with one finger and you can do it quickly. One thing to note is that, if you’re new, it does tend to open early if you’re not using two hands. And you’re not used to using a cup. The point of insertion is larger than the punch-down fold and some others. However, it is one of the most popular and very easy cup folds.


menstrual cup 7 fold

7 fold. If the punch down or the “C” fold don’t work for you, you could try the “7” fold. Squeeze the cup and fold one side over. This gives you a fairly small point of insertion at the tip. With some tapering and also gives you control over when you want to push the cup open.


menstrual cup folding

double 7 fold. Take one side and fold it slightly to the front and take the other side, then fold it slightly down to the back. This gives you that double seven, this is also sometimes referred to as the tulip fold.


menstrual cup folding labia fold

Labia Fold. It is great if you’re having trouble getting a softer cup to open. Take the edge of the cup pinch it, push it down to the middle of the cup, and then squeeze sides around this. What you see is a nub from the top of the cup that’s sticking out from the middle. This is what you can use to push on to try and open the cup if it’s stuck.


triangle folding

Triangle Fold. It is very similar to the 7 fold. Squeeze the cup and make it flat. Take one corner and bring it down all the way to the base. This gives you a very narrow point of insertion, similar to the punch down fold, but it’s also quicker and easier to do with your hands. If you’re doing it correctly you should have the shape of a triangle on your cup.


how to use insert menstrual cup

Origami fold, it is similar to the punch down. You want to start with a half punch but then twist it around. This gives it a little bit of a rosebud shape at the top and this also gives you a handy nub that you can use to help open the cup from the bottom.


how to fold menstrual cup

Diamond fold. To perform the diamond fold you’re going to take one side of the top rim and fold it down on the cup towards the base. Then take the left and right side and roll them inwards until they’re touching. This gives you that flat diamond shape.

folding menstrual cup

The diamond fold is quite large so what most people do is just fold in half, and this is the half diamond fold. You’ve got a much more narrow point of insertion and you also have this great little nub that you can use to pop the cup open when you insert it.


menstrual cup foldsmenstrual cup folding S folds

E Fold. It is quite impractical. Maybe you want to give it a shot and then little “S” fold. But these are going to be hard to insert because they’re going to want to open at the top.

Using a menstrual cup shouldn’t be this complicated, so we would like you to stick with something a lot more simple. Like the “C” fold or the “U” fold. Very easy, fast and simple. Or the punch down fold.

Whether you’re just trying to protect your hair from the chlorine making you more streamline in the water, or if you wear a cap in open water to be seen easier. Swim caps have lots of uses.

There are 5 different types of materials for swim caps, and each of these caps has a different style to suit all types of swimmers. So let’s take a closer look at some.

Silicone swim caps

silicone are the most popular types of swim caps that are worn by swimmers. Silicone caps are very durable and will last for years as long as you look after it. And a big plus is that they are easy to get on and off.

Latex swim caps

Latex swimming caps

The latex swim cap is great if you want to swim at hotter climates as it’s one of the thinnest caps on the markets, but it will still keep your streamline in the water, and another plus is that latex cap is very affordable.

Rubber swim caps

Rubber swimming caps

Rubber swim caps are perfect if you have a latex allergy. They work perfectly in cold waters as they keep your head insulated. And they are very long-lasting.

Lycra swim caps

Lycra swim caps,Spandex swimming caps

Lycra swim cap and Spandex swimming caps are extremely durable and last a long time even against chlorine. They are perfect swim caps wear when training or open water swimming as they have great sun protection.

Neoprene swim caps

Neoprene swim cap

Neoprene swim hats are a must for any type of open water swimming or triathlon. They work in perfect harmony with troy suits to keep you warm in the colder waters, and they don’t pull your hair. Swim caps pulling your hair when putting on or taking off is a nightmare whether you have long hair or short hair.

Swim caps made from lycra and neoprene won’t pull your hair but if you do love your silicone or rubber caps too much, talcum these silicone or rubber caps, now they won’t sticky.

Traditional fun swim caps

silly swim caps

Most swim caps are designed to make you more streamlined in the water, but the more traditional cap isn’t dead. if you’re looking to keep your hair dry and your ears covered or just a cup that is super easy to get on and off, then a traditional swim cap is something you need to consider. Traditional caps can be made from fabrics or rubber, and normally have some classic design. They’re perfect for a leisure swimmer or for aqua aerobics water.

Water temperature is every swimmer needs to think about when buying a new swim cap. Neoprene and Silicone swimming caps tend to be made from thicker materials so they hold the heat for longer. If the pool is 26 degrees or hotter you might overheat, that’s why these types of swim caps are perfect for open water swimmers.

If you are pure pool swimmer then look at the latex caps, they are thinner so you won’t run the risk of overheating in the pool. It’s time for a roundup if you’re looking at a cap for open water swimming, then the neoprene is the right choice for you. It’s thicker so it will keep you warmer for longer in the colder waters.

If you want to be more streamlined in the pool or open water then look at silicone caps they are the industry standard when it comes to competition swimwear.

If you want a cap for fitness and leisure then take a look at getting a lycra or spandex cap, they will keep your hair out of the pool water, and they’re very easy to get on and off. They also last a very long time. They can cover your ears and also they look cool.



Female urination device

Have you ever been to a situation that wants to pee but find a dirty toilet? If yes, what did you do then? Directly sit on the dirty toilet and do not care about hygiene? If you do not want this to happen again, you can use a travel urinal device specially designed for women.

The guys can go to the bathroom just about anywhere but ladies now you can pee like a gentleman too. Female Urination is a reusable silicone funnel that helps you tinkle standing up. Say you’re on a camping trip and nature calls instead of summoning a crisis committee you can now use Female Urination. It’s made of flexible medical-grade silicone that will adapt to your body while it’s anti-spill and anti-splash design keeps things tidy and mess-free. When we tried it out it was super easy and drip-free plus go girl lets you be discreet you only need to undress just enough to give go girl coverage nothing too conspicuous. The pee funnel comes folded in a capsule with an instructional tube that way you can rinse shake and store when you’re done. Female Urination will let you go easily at outdoor concerts festivals road trips or when you’re stuck in the middle of nowhere. Besides being medical grade the silicone is antimicrobial and it can be cleaned and reused wash it with liquid soap and let it dry, wash it in boiling water or you can even run it through the dishwasher on the top rack.

It allows women to pee standing up that can keep the pee as far as away from your body and shoes or your backpack. Thanks to go girl standing up when you pee is way less of a nervously.


silicone molders

Silicone Molds can last for years, when you first get your silicone molds, it’s best to wash them with slightly silty water to get out any oil to debris and either smack the mold until all the water is knocked out or dry them with a lint-free cloth, you can also put your new silicone molds in a commercial or consumer dishwasher just load them with the mold cavities facing down so during the wash cycle the water doesn’t pull and you’ll have hard water drops. It’s also best to avoid these bakes are times.

Silicone molds can be used for freezing or baking but we do recommend that you bake under 400 degrees. If your molds have cocoa butter film, our preferred method for cleaning them is to first wrinkle them all with straight white vinegar, and carefully pour boiling water over the molds face side up, it’s best to let them rest until the mixture is cool enough to work with. Then using the nonabrasive side of a sponge rub the surface until it feels clean, and then rinse with soapy warm water. If after drying the mold surface still isn’t shiny enough just repeat the process.

Now that we’ve washed and dried molds the natural inclination in the kitchen to wrap them in plastic. This isn’t a good idea at all because it’s really skipping fungus and bacteria there which we don’t want. So it needs to breathe so a more ideal situation is to have your sheep pan parchment, put your silicone mold with the facing up so the bottom is flat. And then you also don’t want to store them on top of each other because they might stick and then you’ll be ruining the molds in the face which we don’t want that, you also don’t want to be storing it curled or bent like this because after a while it will retain the shape. And you really can’t get it back to lie flat again.

If you’re traveling in a suitcase or something you need to roll it up for temporary it’s not a problem, you just don’t want to store it that way it’s better to store it flat dry and then you put a piece of parchment paper to protect it from dust and debris. Now you’re good to go store them in a place that’s dry and clean.

Silicone baby bibs are a highly innovative introduction to the market.

Every parent knows that babies are going to make a mess when they eat. It is a tricky business for them learning on how to handle the basics of getting food from the tray to their mouth. Until the baby knows how to eat, you would be going to wind up with some big messes they would make. This is the reason why a good baby bib comes in handy. Oftentimes, a lot of babies’ clothing is ruined by the mess they make when they are eating. Some baby food stain does not come off that quickly which makes washing a difficult task to handle. It is not only the issue of the clothes they wear. But also the mess that they will make when they drop food on the floor. Busy moms had a real difficult time containing these messes they make.

Silicone baby bibs are a highly innovative introduction to the market. These bibs are made from silicone and usually feature a crumb catcher design. There is a pocket that sticks out at the bottom of the bib that catches any food that the baby drops.

Here are just a few advantages Silicone baby bibs offer over the more traditional or plastic baby bibs.

Easy to clean, unlike fabric bibs that need to be constantly laundered. Silicone bibs just need to be wiped down with a damp cloth. Silicone has a non-porous surface which makes it exceptionally an easy task to clean. You can even just toss it in the dishwasher along with your dishes. Anything that can reduce the amount of laundry that has to do with a baby is a bonus.

Crumb catcher design to contain the mess. Babies naturally drop food when they eat. It would not matter when your baby is eating at home. You would most likely clean the mess without giving a second thought. However, when you visit a restaurant with your baby, it is rather humiliating when it comes time to leave because there is a huge mess on the floor. A silicone baby bib with a built-in pocket is an exceptional option to choose. These bibs are designed to catch almost all the food that babies drop while eating. There might still be a few pieces of food that would fall on the floor. But the mess would be far less severe than with a traditional bib.

Cool and cute designs. Silicone baby bibs are available in a wide variety of colors and designs. They could be just about every color of the rainbow. They could look like a cute monster or a friendly tiger. Whatever color and design you choose, there is no doubt knowing that silicone is soft and comfortable against your baby’s skin.

Silicone baby bibs are a great alternative to traditional baby bibs. They are easy to clean and do an amazing job of containing messes and keeping the floors clean with numerous various design options available. You can choose a bib that is completely matched to your baby’s distinct personality.