Electron beam curable adhesives

Table 23. Hot Melt Electron Beam Curable Adhesive. ...

Uses Reaction rate accelerator copolymerizes readily with most other vinyl monomers modifies hydrophilic properties in systems incl. adhesives, coatings, cosmetics, textiles, syn. fibers, textile sizes, protective colloids, lube oil additives reactive diluent in UV- and electron beam-curable systems (coatings, inks, adhesives) aids pigment disp. (inks) intermediate for modified phenolic resins of interest as plasticizers, dye intermediates, textile assistants... 

Formulation details are then presented in Chapters 11 through 14 for the various possible forms of epoxy adhesive systems room temperature and elevated-temperature curing liquids, pastes, and solids. The more or less unconventional forms of epoxy adhesives are also identified and discussed, since these are now achieving prominence in industry. These include uv and electron beam radiation curable, waterborne systems, and epoxy adhesives capable of curing via the indirect application of heat or energy. 

Energy curable adhesives for use in flexible packaging based on ultraviolet or electron beam irradiation are in their infancy. The potential use of these types of adhesive is promising due to the fast cure rate (essentially full cure on irradiation and hence low risk of migratory components) and the potentially... 

Electron beams are more penetrating than UV radiation and can thus be used to bond some opaque substrates that cannot be bonded with UV-curable adhesives. However, this advantage is offset by the... 

The contributions of physics to adhesion are further manifested by the extension of uv- and electron-beam curing of adhesives to low temperatures. Radiation-curable adhesives were originally intended to eliminate solvents in the systems. However, the use of certain toxic acrylate monomers presented some problems. So far, radiation-curable systems have become technologically challenging, but economically less attractive than most thermally cured systems. Since one of the earliest papers on photoadhesives by Nakano (35) many patents have been issued on this subject. Two reviews have been published by Stueben (36). ... 

The papers presented in the following chapters represent advances in pressure sensitive adhesives (ultraviolet light activated acrylate monomer - low Tg polyether formulations) photoinitiated cationic polymerization (light activated aryliodonium and arylsulfonium salts of lewis acids in epoxy resin formulations) polymer and formulation design criteria for radiation curable adhesives radiation curable composites (dynamic thermal analysis characterization of electron beam cured... 

This overview of radiant energy curable technologies for adhesives includes discussions of the form of radiant energies, where they are used, their market size, chemical nature, and properties. The article centers on ultraviolet, infrared, and electron beam technologies. 

Electron beam curing EB curable adhesives use the radiation of an electron beam to initiate curing. The electron beam has the advantage that it can penetrate through material that is opaque to UV light... 

Nearly 42% of the demand for all adhesives comes from the packaging sector. Radiation-curable adhesives are used primarily for packaging, with paper and paperboard the dominant materials used in the packaging. Radiation-curable adhesives can be used on glass, metal and some plastic materials. Other applications for radiation-curable adhesives are in healthcare, electronics, communications, pressure-sensitive tape and consumer applications. Ultraviolet (UV)-curable adhesives are best suited to small-scale applications, while electron beam (EB)-curable adhesives are more appropriate in high-volume applications (an EB system has a higher installation cost). One additional characteristic of EB-curable adhesives is that they can cure the area between two substrates. UV light-cured adhesives can also be applied on heat-sensitive substrates and are not affected by ambient temperature or humidity. 

Electron beam (EB)-curable laminating adhesives for flexible packaging,... 

Radiation curable adhesives Inclusion of a photo initiator in some one-component-type resins allows initiation of cure by ultra-violet or visible light, or by an electron beam. 

Another effective way to cure nontransparent samples is by using electron beams (EB) that can initiate both radical and cationic-type polymerization. EB-curable laminating adhesives have been shown to exhibit good performance over a wide temperature range on a variety of... 

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