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Seamless capsules

What are seamless capsules?

A seamless capsule is a type of soft capsule without a seam, which is produced using properties such that a liquid becomes spherical due to interfacial tension. There is a large degree of freedom in configuring the grain diameter, which can be anything from an extremely small 0.5mm up to around 10mm, and there is also a wide range of options in terms of membrane thickness and hardness, so as the final product form it is possible to use capsules separately, or even as small-granule capsules mixed/combined in powders, granules, capsules/tablets, gummi candies, gums, and liquids, etc.

Seamless capsule form

The production principle of seamless capsules means that they can only be spherical.

Strengths of seamless capsules

A seamless capsule is a type of soft capsule, so the strengths of soft capsules also apply to seamless capsules. In addition, seamless capsules have the following characteristic strengths.

1. Wide range of choices of grain diameter

Grain diameter can be set to any size of capsule, ranging from around 0.5mm to 10mm, depending on the purpose.

2. Wide range of choices for capsule membrane thickness/hardness

The thickness of the capsule membrane can be set to anywhere from several tens of μm up to several thousand μm.
Also, depending on the purpose, the hardness of the membrane can be set to anything from extremely soft (fresh agar capsule) to hard.

3. Wide range of choices for dissolution time of capsule

The timing of dissolution inside the body can be set from units of seconds to hours.

4. Heat-resistant capsules can be made

Even at high temperature, contents can be protected without the membrane breaking.

5. Depending on membrane type, it can be possible to mix inside aqueous solution

By using a seamless capsule, oil-based ingredients can be mixed in aqueoue solutions without using a surfactant (practical uses in drinks, face lotion, shampoo, etc.)

Seamless capsule manufacturing method

Seamless capsule manufacturing process

General preservation/storage conditions for health-foods

Except for special items, health-foods (soft capsules, hard capsules, seamless capsules, tablets, granules, jellies and mini-drinks) are normally kept at room temperature, and even from the perspective of the composition of contents and changes in appearance, etc., it is necessary to avoid high temperatures and high humidity, as well as sudden changes in temperature, and as with general foodstuffs, efforts should be made to keep health-foods in stable and secure conditions. In general, the following conditions are desirable.

◎Temperature 30℃ max.(avoid placing inside vehicle, on vehicle dashboard/trunk, or in bag, etc.)

◎Humidity RH60% max.(Avoid kitchens/drainage area and places where rust/mold easily occur)

◎Light . (Avoid direct sunlight)

◎Oxygen (air) .(After opening, firmly close stopper or fastener, etc. to prevent contact with air)

Detailed preservation/storage conditions are described below.

Seamless capsules

(1) Changes in the appearance of seamless capsules

In general, seamless capsule products should preferably be stored at a normal temperature (15-25°c) with a relative humidity of 40-60%. In conditions other than these, or if stored unsuitably, exterior changes in appearance of the dry type or the fresh type may occur, as shown in the following examples.
① Dry type
1) In high temperature/high humidity conditions, or if there are sudden changes in temperature, capsules may stick to each other, and dents and bubbles may appear.
2) Seamless capsules are affected by moisture, so if capsules are handled with wet hands and returned to the packaging, or if a drop of water, etc., accidentally enters the packaging, the capsules will soften and the membrane may dissolve causing the contents to leak out.
3) There are no restrictions when setting the thickness of the seamless capsule membrane, but the effect of pressure will increase as the membrane becomes thinner, and deformation and breakages will be more likely to occur.
② Fresh type
1) Fresh type capsules are soaked in the optimal preservation liquid, but deformation occurs easily if stored at high temperatures.

2) If the capsules are removed from the preservation liquid and left exposed for a long time, deformation may occur.

(2) Seamless capsule content stability

The stability of ingredients contained inside seamless capsules varies depending on the prescription. The membrane of a seamless capsule is thinner than that of a punched soft capsule, which means that in some cases stability is slightly inferior to that of punched soft capsules.

(3) Seamless capsule preservation/storage conditions

As mentioned above, the desired storage conditions for seamless capsule products are normal temperatures (15-25°c) and a relative humidity of 40-60%, and it is important to avoid as much as possible conditions where there are very high or low temperatures and levels of humidity.
 Also, seamless capsules should be stored in such a way that they are not subjected to external pressure, as this can cause deformation or breakage. For the fresh type, care must also be taken to prevent bacterial contamination after opening.
 If you would like to request soluble (fast-release) formulations such as mouth fresheners, please inquire about the “S-Capsule” ultra-fast-dissolving capsule our company has developed.

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