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What is eyelash extension sealer?

What Does Eyelash Extension Sealer Do And Do I Need It?

There are a variety of factors that can cause your client’s eyelashes to fall out after walking out of the salon. In many cases, investing in a good bottle of lash sealer can help to retain your client’s eyelash extensions!

Eyelash extension sealer is especially beneficial for clients who suffer from the followings:

  • A build-up of dirt, oil and other pollutants from day to day living 
  • Any residue that may be left and built up from makeup products
  • Dry and brittle eyelashes, short or sparse eyelashes 
  • Irritations, redness, infections or soreness around the eye line

What does an eyelash extension sealer do?

Imagine what top-coat nail polish does for a manicure. That’s what eyelash lash sealer does for eyelash extensions. The basic function of a lash sealant is to form a barrier to protect against the elements that break down the lash glue. This 'sealed effect' helps to create maximum retention as well as to prevent extensions twisting.

So often, lash clients are instructed not to put anything on their lashes. Why is this different?

Unlike other cosmetic products, a lash sealant is a water-soluble, oil-free, functional aftercare product that prolongs the retention of lash extension.


How does wearing a lash sealer affect the look of lash extensions? What can clients expect?

Because of the character of its material, wearing an eyelash sealant will add a slight shine to the look of lash extensions (however, almost not visible to eyes). 

Our Black Diamond Coating Sealant contains Gardenia Florida fruit extract- which naturally adds deep black color to our sealant as well as being a powerful antioxidant. Thanks to this wonderful natural ingredient, our sealant adds deeper black color to the lash extensions- which makes our clients’ lashes look more defined.


When lash artists look for a lash sealer, is there anything they should watch out for?

There are a few lash coating sealers are available but see if the one you’re about to buy has added benefits for lash growth! 

If you’re trying to convince a client to invest in a lash aftercare product, recommending ONE product has multiple benefits (prolongs retention + lash strengthen + promote lash growth) is better than trying to sell several products.  

Also, note that there are different colors of lash coating sealants are available (clear or black) as well as different brush types (mascara-tip type or brush-tip type).


What ingredients are in BL Black Diamond Coating Sealant that is beneficial to the lashes?

Our worldwide best-selling Black Diamond Coating Sealant addresses solves specific problems salon professionals and lash clients' experience with eyelash extension retention. 

The black Diamond lash sealant is formulated with proven ingredients like allantoin, hyaluronic acid, essential B Vitamins to ensure your client’s natural eyelashes get the hydration, protein, and vitamins they need. 

Not only that, packed with earthy natural ingredients from Eastern medicine with proven results derived from thousands of years of research and use, but Black Diamond Coating Sealant is also a holistic aftercare product you can provide for your client’s long-term lash health and beauty.


Frequently Asked Questions about Eyelash extension Sealer (FAQ)

Do you have a clear lash sealer, too?

Yes, our Crystal Drop Coating Sealant is a clear color and great for use when you have color lash extensions. It is made with the almost same ingredients as Black Diamond Coating Sealant.

The only difference is, Crystal Drop Coating Sealant doesn't contain 'Gardenia Florida Fruit Extract'- the natural black dye component that gives Black Diamond Coating Sealant that gorgeous dark tint. 


When can I start using the eyelash sealer?

Eyelash extension adhesive can still be in their curing phase even after 24~36 hrs. We recommend starting using eyelash extension coating sealant 2~3 days after the treatment to make sure it doesn't cause any blooming effect.  


Can I use the lash sealer on my volume lash, too?

Many people believe that the lash coating sealant can only be used on the classic lash extension but in fact, you can absolutely use the coating sealant on the volume lashes, too. Just make sure you brush them thoroughly with a fresh mascara brush. 


How often should I apply the lash coating sealant?

Many people believe that the coating sealant can only be used on the classic lash extension but in fact, you can absolutely use the coating sealant on the volume lashes, too. Make sure you apply a light coat on the lashes and brush them thoroughly with a fresh mascara brush afterward so your lashes don't stick to each other. 


How do I apply the coating sealant?

Same as how you'd apply mascara! Apply it evenly on the eyelash but avoid contacting your eye line. (It's tricky to clean the coating sealant when applied on the eye line!) Once applied, brush them well with a dry lash wand.


Extra Tips when using an eyelash extension sealer:

  • When you apply a lash extension sealant, it will temporarily create this ‘wet lash’ look. That’s totally normal. It is important to use a new, dry lash wand to spread the lash sealer all over the extensions (and volume fans especially) so the extensions don’t stick together.    


  • Don't apply a sealant all the way onto your skin (lashline) but give it about 2~3mm room from the lash root. (It's really tricky to clean the coating sealant when applied on the lash line!)


  • Just like any other water-based aftercare product, we recommend our lash clients using a coating sealant 48 hours after the lash extension application when the lash adhesive is completely cured. 


  • In case you want to apply a sealant onto your client’s fresh lash set at the end of the service, avoid applying the sealant to the part where the adhesive is applied. 


  • Lastly, if applying a sealant at the end of the service is part of your salon’s application routine, we recommend you to use a “brush-tip” lash coating sealant, instead of a “mascara-tip” lash coating sealant. Using one mascara type lash coating sealant on several clients’ lashes carries a risk of cross-contamination if any of your clients has an infection. So, wet a new, fresh lash wand by using a brush-tip sealant and use the lash wand on a client. 


  • Once opened and used, the recommended shelf-life for one bottle is 6 months.   


Our philosophy behind the eyelash coating sealer

When we developed this coating sealant we dove deeper than just aiming to add a protective layer to your client’s eyelash extensions. Our approach was one that addressed eyelash retention issues in not just a troubleshooting way but also a preventative and holistic measure for much longer-term lash health.

BL Black Diamond Coating Sealant has been scientifically formulated with a winning formula of B vitamins, acids, and natural extracts to heal, moisturize, and protect your customer's natural lashes. 


1. Heals & Moisturizes Lashes with Acids

how to make your lash extensions last longer with eyelash extension sealer

Lack of moisture in natural lash results in the weak, brittle lash condition. And this is not a great foundation for a fluffy voluminous set of eyelash extensions. 

Healthy, hydrated lashes not only look great but they are stronger and assist in preventing eyelash extension fallout. 

Injecting deep hydration into natural lashes is the first step to long-lasting lash beauty. For this, we have added the two essential acids into our sealant- Sodium Hyaluronate and Allantoin. 

Allantoin and Sodium Hyaluronate are often combined as they both are excellent ingredients that complement each other in ensuring your eyelashes remain ultra-hydrated. 

When used as a combination, they noticeably increase the results of eyelash serum. This wonderful combo ensures natural eyelashes to be strong- which will result in a longer-lasting eyelash extension. 


Allantoin for healing damaged cells

Allantoin is extracted from the Comfrey plant where it is the main active ingredient. Grown in temperate climates of Asian and Europe, the leaves from the Comfrey plant have been used for centuries to reduce skin swelling and heal minor skin injuries. 

Allantoin works by increasing the water hydration to the molecules in your body that are composed of collagen, enzymes, and glycoproteins. 

Allantoin is a non-allergenic, non-toxic ingredient. As an ingredient, it has powerful soothing and healing properties. In our eyelash coating sealant, Allantoin works as emollient adding moisture while deeply conditioning your eyelashes ensuring they look smooth and glossy.


Sodium Hyaluronate for Deep Moisturizing

Sodium Hyaluronate is the salt of hyaluronic acid. This ingredient is currently HUGE in skincare for its ability to moisturize and hold moisture and collagen in your cells, making it look younger and plumper. 

Sodium hyaluronate contains qualities that restore volume in cells. Therefore it is an excellent ingredient in eyelash serums, as it assists with growth and volume while lubricating and moisturizing natural lashes. 


2. Improves Critical Lash Health with Essential B Vitamins

How to Make Your Lash Extensions Last Longer with eyelash extension sealer 2

Natural lashes can often get dry, brittle, and lack elasticity. This makes extensions hard to hold as there is no natural curl to support them and dry, stiff natural lashes can get twisted or break off more easily. The thinner your client’s eyelashes are, the weaker they are which makes it almost impossible for them to support the weight of their eyelash extensions. 

The B vitamins we have chosen to include in our Coating Sealant are excellent with addressing several issues regarding the elasticity of lashes.

According to the scientifically proven research and results, B vitamins have been proven to be essential in promoting eyelash’s elasticity, growth, thickness, and retention. The following B vitamins we chose to include in our formula are as following:  

Panthenol for Lash Elasticity 

Panthenol is an excellent emollient as it has moisturizing properties that penetrate, condition, and infuse the damaged eyelashes. We included it in this Coating Sealant as it helps hydrate, heal, and rejuvenate the eyelashes.

Biotin for Lash Strengthening  

Biotin is a wonder vitamin when it comes to ensuring healthy, long, full eyelashes. This water-soluble B-vitamin is found in many premium serums or quality mascaras to ensure optimum eyelash health.

Biotin was once known as Coenzyme R and vitamin H. The H stood for Haar und Haut, in German this translates to hair and skin. Biotin is known for its wonderful ability in strengthening and retaining eyelashes. Biotin is involved in blood cell production and hormone secretion- effective in improving scalp health and preventing hair loss.

We added it to our eyelash serum to ensure that the root of your client's eyelashes are strengthened and premature lash fallout is minimized. 


3. Nourishes Lashes with Natural Extracts from Eastern Medicine

How to Make Your Lash Extensions Last Longer with Coating Sealant

Korean beauty aka K-beauty is known for its use of traditional Asian ingredients that are widely used in Eastern medicine. These ingredients have now been introduced to cosmetic and skincare lovers offering them a more natural and holistic approach to their beauty routine. 

Once exclusively used in Eastern medicine, these earthy natural ingredients are now being added in creating serums, essences, and other beauty treatments, replacing harsh chemicals and additives made from the lab. 

We have aligned our aftercare product with natural plant extracts to provide a holistic approach to lash care and its health. 

We have added the patented combination of 6 natural extracts called 'Yookmijahwang'. They are known to have special effects in preventing hair loss and in promoting hair re-growth.   

Rehmannia Glutinosa for Anti-inflammation

How to Make Your Lash Extensions Last Longer with Coating Sealant

Rehmannia Glutinosa is grown wild in North and North-Eastern China. Its root is yellow-brown to blackish brown and harvested in Fall after the plant has flowered in the previous Spring. Rehmannia Glutinosa has been used as a remedy for many ailments in traditional Eastern medicine, primarily for its ability to reduce inflammation and soothe the body.

It is considered to be a cooling herb and is renowned as a longevity herb in Eastern medicine with a history of it being used for over 2000 years. 

We added Rehmannia Glutinosa to our eyelash Coating Sealant as it provides soothing properties to the sensitive eye area. 


Cornus Officinalis Fruit extract to Reduce Skin Irritation

How to Make Your Lash Extensions Last Longer with Coating Sealant

Cornus Officinalis Fruit extract is a commonly added ingredient in K-beauty and Asian beauty serums. Its Korean name is san soo yu and it is extracted from a shrub called Cornus that grows and is found in East Asia from China to Korea, usually in the wooded areas and forests. 

In this shrub, flowers and berries have long been used as topical applications in Eastern medicine. When used in eyelash Coating Sealant, this powerful Eastern medicine assists relieving soreness and irritation with its anti-inflammatory properties.

By adding Cornus Officinalis Fruit extract to our eyelash Coating Sealant, it benefits your client’s eyelash extensions by ensuring they remain healthy and irritation-free. 


Alisma Plantago-Aquatica Extract for Reducing Eye Infections

How to Make Your Lash Extensions Last Longer with Coating Sealant

Alisma Plantago-Aquatica is an aquatic growing plant that is found all over the world in countries as diverse as Asia, Africa, North America, Europe, and Australia. Alisma Plantago-Aquatica grows in shallow waters all year round and it has benefits that can be traced back to the 1500s. 

We added it to our eyelash Coating Sealant because along with being an anti-irritant, its rich in antiseptic and anti-microbial properties. These assist in reducing eye infections that can be caused by bacteria and dirt build-up from eyelash extensions. 


Paeonia Suffruticosa Root Extract to Fight Bacteria Growth

How to Make Your Lash Extensions Last Longer with Coating Sealant

Paeonia Suffruticosa is a name used for a group that falls within the variety of tree peonies. In Korea, they are called mok-ran. The root bark of Paeonia suffruticosa has been used in Eastern medicine for over 2000 years, the plant is still mainly grown for medicinal uses. 

Paeonia suffruticosa is valued for the active ingredient Paeoniflorin which has anti-bacterial, anti-inflammatory, and antioxidant properties.

We included it in our eyelash serum for these organic properties as well as its ability to reduce redness and irritation. 


Gardenia Florida Fruit Extract for Antioxidant Quality

How to Make Your Lash Extensions Last Longer with Coating Sealant

Long used in traditional Eastern medicine, this ingredient is known and used for its antioxidant qualities in cosmetic products. It is a natural source of Crocin, which is considered to be a powerful antioxidant, as well as slowing aging activity.

We included this extract in our serum for its antioxidant properties. It helps to refresh, revive, and soothe the delicate eye area. 


Poria Cocos Extract for Boosting the Immune System

How to Make Your Lash Extensions Last Longer with Coating Sealant

Poria cocos are part of the (Polyporaceae) mushroom family and are a fungus grows on the root of pine trees, known for its use in traditional Eastern medicine for thousands of years.

We at BL Lashes included this ingredient in our serum as it is known for its antioxidant properties and its ability to boost the immune system of the sensitive area around the eyes



Further reading:

How to Properly Care for Lash Extension Adhesives?

The Best Lash Extension Adhesive for Sensitive Eyes

The Secrets Behind Lash Extension Retention - Glue & Humidity


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