Application: Precisely moisten and bond paper, cardboard and tissue
Liquid materials in paper and tissue processes
In paper and pulp processing, water, adhesives and other liquid process media are applied precisely to webs, layers, edges or individual products. Tasks range from controlled moistening to bonding paper layers or securing the tail sheet of a tissue roll.
Since paper and tissue absorb moisture very quickly, the products react sensitively to uneven distribution. Too much medium can cause waves, spots, punches or web problems. By contrast, a too low application leads to insufficient humidification or unsafe adhesive compounds.
Typical applications
Typical spray and adhesive processes are:
- Tail-sheet bonding for toilet paper, kitchen rolls and other tissue products
- Adhesive application on paper, cardboard and packaging webs
- Adhesive several layers or sub-areas
- Moisture to influence flexibility, flat position or further processing
- edge, strip and spot application
- Application of liquid auxiliaries to selected zones
- Applications on discrete products as well as continuous webs
High web speed and short reaction time
In the case of fast-running machines, the spray application must be synchronised exactly with the web speed. Spray start, spray finish and application width must not move despite speed changes. In the case of tissue products, it is added that very light and absorbent materials must not be disturbed by too high air impulses or too large drops.
For adhesives, open time, wetting and pressing or winding process must fit together. Drying glue on the nozzle can change the spray pattern. An application that is easily accessible and easy to clean is therefore particularly important for system availability.
From the tissue tail to the cardboard box
The requirements vary significantly depending on the product. In the case of tissue rolls, a small amount of adhesive must securely fix the end sheet without having to glue several layers unnecessarily. On the other hand, continuous strip or surface application may be required for cartonboard and paper webs. During humidification, the uniform distribution of water or process medium is in the foreground.
The spray solution is therefore not selected solely according to the web width. Product thickness, absorbency, winding tension, press contact and subsequent cutting or packaging steps are also taken into account. A too wide or too wet track can disturb the process as well as an interrupted adhesive line.
- Tail-sheet bonding to tissue rolls
- Stripe application on paper and cardboard
- Moisture before forming or winding processes
- application to selected areas for lamination and bonding
- Coordination with cutting and packaging steps
Krautzberger solutions for fluid application
Compact automatic spray guns can be positioned over or next to the track and synchronized with machine control. Depending on the desired width, flat or round beam as well as several parallel arranged apparatuses are eligible. Manual spray guns are available for manual settings, tests or small series.
The supply can be made via material pressure vessels, diaphragm pumps and material pressure controllers. This makes it possible to achieve constant application quantities even during long operating times. Material replacement valves and rinsing options support product changes and cleaning processes.
Decisive process parameters
For a clean application medium, paper quality, surface weight, absorbency, web speed and subsequent process must be considered together.
- application quantity per area or product
- Drop size and spray width
- Distance from the track and air movement
- Viscosity and temperature of the adhesive
- Switching time and synchronization with the machine movement
- Avoiding fog, deposits and soiling
- Cleaning interval and accessibility of the nozzle
Clean plant environment for adhesive and water
Fine spray mist can settle on rollers, sensors and guides. The spray equipment should therefore be positioned as close as possible and aimed precisely at the intended zone. Shields and suitable extraction can further reduce carry-over to other areas.
Water and adhesive lines must be treated differently in case of prolonged standstills. water may involve microbiological and corrosive requirements; Glue can dry up and block nozzles. The cleaning routine is therefore defined separately for each medium.
- targeted spray direction and short distance
- Protection of rollers and sensors
- Media-compliant flushing at standstill
- planable cleaning intervals
Benefits for your production
- even humidification or adhesive distribution
- Reproducible end sheet and layer bonding
- Low media consumption
- clean bordering of strips and partial surfaces
- Integration into fast continuous lines
- less standstill due to coordinated cleaning and flushing concepts
Process tests with original material
Paper, tissue and cardboard differ greatly in absorbency, surface structure and sensitivity. Adhesives also react differently to pressure, air and nozzle cross-section. Original medium and representative material samples can be used in the Krautzberger technical test centre.
Spraying, wetting, application quantity, punching, adhesive effect and cleaning behaviour are tested. On this basis, the application can be transferred to the later machine process.
Related products
All products
Suitable solution for paper, tissue and board processes
Are you looking for an automatic sprayer for end blade bonding, humidification or adhesive application? Krautzberger supports you in the selection of nozzle, material supply and system integration.
Contact us to discuss the medium, paper quality, web speed and application width.
Industries for this application
Paper and tissue absorb moisture quickly. Water and adhesive must therefore be precisely dosed along the web, at edges or on individual products, from moistening to securing the final sheet.
