In physically hardening, solvent-based adhesives, the bonding substances, also called binding agents, are dispersed in an organic solvent. When the solvent evaporates, the adhesive changes from liquid to its final solid form – the pure bonding substance remains.
The function of the relatively highly volatile solvents is to facilitate an easy transport and application of the adhesive: They ensure that the binding agents stays liquid and can therefore be processed. In addition, the solvents also influence key adhesive characteristics such as adhesion, by promoting the wetting of the substrate or by biting the substrate surface, or dwell time and open time, depending on how fast they evaporate.
Jowat has developed the Jowatac-HighSolid® and Jowatac® Super-HighSolid systems to reduce the flammability of the adhesive and the amount of volatile organic compounds (often also called VOC) released into the environment. The Jowat portfolio therefore provides a wide range of adhesives from general-purpose products to special formulations.

Product series, characteristics and applications:

Jowat® CR adhesives

Basis: Polychloroprene rubber
Application: Assembly operations, bonding of rubber/leather (shoe industry), rubber/metal (seals) or bonding plastic boards to sheet steel – also on vertical surfaces.
Characteristics: Chloroprene rubber (CR) adhesives are characterised by an immediate initial strength which provides a major benefit in applications with fast downline processing or for when vertical surfaces have to be bonded. To ensure the highest possible initial strength, the dwell time should be long enough until the adhesive layer is dry to the touch. The bond is formed immediately as soon as the two substrates coated with a touch-dry film of CR adhesive (also called contact adhesive) are then shortly pressed together with high pressure. The adhesive will keep its ability to form a bond upon contact for a limited time after the solvents have evaporated.
In many cases, completely dry adhesive films can be reactivated with solvents or by heat. When the adhesive is reactivated by heat, the timing and location of adhesive application incl. drying and of the actual joining process can be independent of each other, facilitating a precoating of the bonding partners.
Supply form: liquid, bucket, hobbock, drum, IBC

CR adhesives provide the following benefits:

many different applications
very high initial strength
wide range of adhesion to different materials
high heat resistance
 

Jowatac® SC adhesives

Basis: Styrene copolymer rubber
Application: Assembly of upholstery furniture, foam converting: bonding of upholstery materials, soft foams, to each other and to fleece, insulating materials and other materials.
Characteristics: Solvent-borne adhesives based on styrene copolymers (often also called SBS or SIS adhesives) are generally applied with spray guns, and are characterised by a good spraying performance and a relatively high solids content. For this group of adhesives, one or both substrates can be coated. A major part of the solvents already evaporate during spraying which leads to a huge increase in the viscosity of the adhesive. These adhesives can therefore also be used for bonding very porous substrates.
Even when applied in thinnest layers, SC adhesives have a very high contact tack during their open time. Joining the substrates while there is still a small amount of solvent in the adhesive ensures a proper wetting of the bonding partner and a fast build-up of initial strength even with low pressure or in high-tension bonding. After all solvents have evaporated, there should be no residual tack. The bonded substrates then can be covered with fabrics or other materials, for instance in the production of mattresses and upholstery furniture.
Supply form: liquid, bucket, hobbock, drum, IBC

Classification into

Jowatac® up to 49 % solids content
Jowatac-HighSolid® 50 – 70 % solids content
Jowatac® Super-HighSolid SC adhesives > 70 % solids content

SC adhesives provide the following benefits:

high initial strength
excellent tack
good adhesion to many substrates
long open time, depending on the formulation
high solids content possible
high content of renewable raw materials
often economical adhesive group
easy handling due to application by spraying
 

Jowat® PU adhesives

Basis: Polyurethane
Application: Upholstery furniture and seating furniture, bonding of substrates containing plasticisers
Characteristics: Solvent-borne contact adhesives based on polyurethane (PU or PUR) are characterised by resistance to plasticisers and good adhesion to the most different materials (except bare metal). Therefore they are used for bonding soft PVC to each other as well as to many other materials. Similar to CR adhesives, they can also be reactivated by heat (e.g. in vacuum deep-drawing methods for the lamination of formed parts with flexible top layers).
To achieve good heat and plasticiser resistances, the adhesive is usually mixed with 3 – 7 % crosslinking agent before processing. The immediate strength is built up by physical hardening while the final strength is achieved by chemical crosslinking (final strength after approx. 3 – 5 days).
Supply form: liquid, bucket, hobbock, drum, IBC

PU adhesives provide the following benefits:

very soft adhesive seam
high heat resistance and good resistance to plasticisers when mixed with crosslinking agent
very good ageing resistance of the adhesive