Bonding base material of Eisai hot melt pressure sensitive adhesive

The main bonding substrates of Eisai hot melt pressure-sensitive adhesive include non-woven fabric, plastic, PE film, toilet paper, spandex silk (rubber tendon) and so on.

1 Non-woven fabric

Non-woven fabrics for disposable health products include hot rolled non-woven fabric, hot air non-woven fabric, spunbonded (SS) non-woven fabric, spunbonded - melt-blowout - spunbonded (SM S) non-woven fabric, chemical bonding non-woven fabric. Among them:

A Hot rolled non-woven fabric, hot air non-woven fabric, hydrophilic non-woven fabric is usually used for surface layer or wrapping material;

B Coarse denier fiber hot air non-woven fabric and chemical bonding non-woven fabric used for diversion layer;Hydrophobic spunbonded non-woven fabric is used for substrate composite;

C Spunbonded - melt-blowout - spunbonded (SMS) non-woven fabric is used for leakage prevention and urine barrier.

2 Plastic PE film

Plastic PE film has breathable film and non breathable film. Breathable film is the addition of inorganic filler (such as calcium carbonate) in the raw material, the use of inorganic filler particles (1~ 10 m) in the process of stretching and the joint of the plastic film matrix being shaped to separate each other to generate micropores. Non-breathable membrane is made of PE plastic particles by extrusion flow, with high transparency, uniform thickness and other advantages.

3 Toilet paper

Toilet paper is made of pulp board or wet pulp by defibrillating, beating, wet part into a net, drying, cutting and other processes. Toilet paper is mainly used to carry or wrap the absorption core (wood paddle mixed polymer), to maintain the integrity of the absorption core in the process of production and use, to prevent the absorption core from breaking and clumping. At the same time, it also has the function of accelerating the absorption and diffusion of body fluids. Most disposable sanitary products use wet strength paper with high wet strength.

4 Spandex (elastic)

Spandex (rubber) is used for leg contraction members, leakproof separation edge of the left and right end of the non-woven components. The contraction component of leg circumference ensures good fit between the diaper and human body. The elastic member of the free end of the leak-proof edge non-woven fabric makes the leak-proof edge non-woven fabric stand up, so as to better fit the human body and limit the leakage of body fluids from the side of the product. Spandex is a polyurethane circular elastic fiber roll packaging material, commonly known as Spandex.

Coating equipment and coating method of Eisai hot melt pressure sensitive adhesive

1 Coating equipment

The coating equipment of Eisai hot melt pressure-sensitive adhesive is composed of glue cylinder, glue pump, glue gun, pipe, electronic control component, spray glue control device, optional accessories, etc. Usually glue cylinder, glue pump, electronic control components, spray glue control device and other assembly into glue machine.

2 Coating mode

The coating mode of Eisai hot melt pressure-sensitive adhesive is divided into contact coating and non-contact coating two types:

A Contact coating is limited to contact scraping;

B Non-contact coatings include: non-contact scratch coating, fiber spray, Surewarp, strip spray glue, etc.

C Among them, contact scraping: it is used in glue places such as back glue, wing glue, three-point glue in independent sanitary napkin bag, urine display glue, and structural glue of upper and lower toilet paper.

D Non-contact scraping: mainly aimed at the phenomenon of contact scraping easily scalded materials, a sizing method without contact materials, but the current technology can not achieve the effect of contact gluing.

Process parameters of Eisai hot melt pressure sensitive adhesive

The process parameters that affect the bonding effect of hot melt adhesive are machine opening time, gluing temperature, gluing amount, compound pressure, etc.

A、The opening time of the machine is the time of the hot melt glue from the glue head to the compound area, generally measured in seconds. It can affect the temperature of the hot melt adhesive and the wetting of the second substrate. In theory, the shorter the better. But in practice, we should also consider the location of the glue head, or consider the limit of production speed. The opening time of hot melt adhesive refers to the time that the hot melt adhesive maintains initial viscosity after coating. The opening time of the machine must be far lower than the opening time of the hot melt adhesive, otherwise the hot melt adhesive has been cooled and solidified before composite so that the bonding effect becomes worse.

B、Gluing temperature refers to the temperature of the hot melt glue inside the glue head. Temperature affects the wetting of the hot melt glue to the substrate. Theoretically, the higher the temperature, the better, but considering the thermal stability of the hot melt adhesive, the heat resistance of the substrate, in general, because of the loss of some heat before the composite, the longer machine opening time and spray glue gluing process needs to set a higher temperature. When adding glue to a small number of times, otherwise the temperature of the glue box will fluctuate greatly.

C、The amount of glue will affect the cooling rate of hot melt glue, and thus affect the wetting of the second substrate. Theoretically, the less gluing amount of hot melt adhesive, the better, but must consider the final adhesion requirements, opening time, etc. Generally speaking, when the opening time of the machine is longer, the amount of glue should be larger.

D、Compound pressure

Recombination refers to the bonding of two substrates under pressure. Composite pressure is the pressure given by the machine when the two layers of substrate are bonded together. Compound pressure will affect the wetting ability of hot melt adhesive on the substrate, so that the hot melt adhesive penetrates into the two substrates, determines the surface shape of the bonding area, and the hot melt adhesive should enter the compound roller as soon as possible. Theoretically, the greater the compound pressure, the better, but need to consider the mechanical properties of the substrate bearing capacity, roller wear, and cementing.