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Method of coupling wireless portable communications device to electronicmail server by public wireless communications network when out of communication with private wireless communicationsMethod of coupling wireless portable communications device to electronicmail server by public wireless communications network when out of communication with private wireless communications description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20060208858, Method of coupling wireless portable communications device to electronicmail server by public wireless communications network when out of communication with private wireless communications. Brief Patent Description - Full Patent Description - Patent Application Claims
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority under 35 U.S.C. Section 119 to German application DE 10200517912.6, filed 18 Apr. 2005. FIELD OF THE INVENTION [0002] The subject of the invention is a process for curing one-component adhesives/sealants comprising surface-deactivated solid polyisocyanates by means of microwave radiation, as well as the use of this process for adhesively joining plastic substrates DISCUSSION OF THE RELATED ART [0003] In modern industrial production, there is often the need to bond plastic substrates together by adhesion. More and more frequently, especially in the automobile industry, parts and modules, such as lamp housings or automobile headlights, are manufactured from plastics. For this, older joining processes are known, in which a headlight housing has a U-shaped sealing bed on a first side wall into which a second part, for example a closure or a covering device of glass having a second side wall, is inserted such that both parts are sealed and joined together. Nowadays, lenses of plastic substrates, for example of polymethyl methacrylate (PMMA) or polycarbonate (PC), are frequently used instead of glass closures or covering lenses or also headlight lenses. [0004] Today, plastics are often bonded together by means of 2-component products that cure at room temperature. This is often due to the fact that the substrates suffer thermal damage at high temperatures and consequently cannot tolerate adhesives that imperatively require these temperatures to reach their final strength. At room temperature, the curing is indeed substrate-friendly, but takes much longer than high temperature curing. This problem can be mitigated by using 2-component products with a short pot-life. However, this advantage is achieved at an additional cost to the application (more frequent changes of static mixers or/and cleaning out mixed material). A further advantage can be obtained if, after application, at least a handling strength can be achieved by means of an energy input, e.g. by thermal energy in a circulating-air oven or by the use of hot-air techniques or even by radiation energy (e.g., infra-red heating). These measures only partially solve the problem, however, and require the use of expensive equipment. A one-component product that is substrate-friendly at relatively low temperatures and which almost reaches its complete final strength in a relatively short time would be a favorable solution to the problem. [0005] One-component polyurethanes based on microencapsulated isocyanate have been known for about 20 years and have been introduced in the market in the form of various adhesives and sealants for automobiles and commercial vehicles. In this field, the state of the art for curing these products is by means of thermal energy, e.g., in a circulating-air oven, through which the automobile bodies in any case must transit to dry/cure the priming coat, fillers or paints. In particular cases--mostly for mounted parts--the hot air method can be used, whereby the hot air is only blown onto the area of e.g. glue lines. [0006] A process for bonding moldings with heat-curable adhesives by irradiating the adhesive joint with electromagnetic radiation is described in WO 03/076167. The adhesive joint should be such that in the region of the adhesive joint, at least one of the moldings of the substrate is transparent to electromagnet radiation, particularly infrared radiation. The mass of the adhesive in the adhesive joint should then be irradiated with energy-rich infrared radiation (near infrared (NIR)). Heat curable adhesives, based on a non-aqueous dispersion, which comprise one polyisocyanate that is deactivated only on the surface and at least one polymer that is reactive to isocyanate are proposed as the adhesive. A disadvantage of this process is that the adhesive joint should be such that at least one of the moldings to be joined is transparent to IR-radiation in the region of the adhesive joint. A further disadvantage is that the IR-radiation not only heats the adhesive, but very frequently also the region of the mounted part close to the adhesive. [0007] Apart from these conventional methods, microwave curing of polyurethanes has proven to be particularly advantageous when raw materials that are suitable for microwave cure are used together with conditions for this method that are favorable to highly active catalysts. In this case it is also possible to realize good and durable adhesion on critical primer coatings that, due to their low surface tension, are difficult to wet. [0008] Accordingly, there was the need to provide further processes to bond plastic molded parts, enabling a rapid adhesion and production process leading to a durable bond of the mounted parts, and which are less dependent on special constructive limitations in relation to the transparency to activating radiation. [0009] The use of microwave irradiation for curing sealants and adhesives is understood in principle, thus a process to at least partially cure sealants and adhesives, particularly in connection with the direct glazing of motor vehicles, is described in EP 318542 B1, the sealant and adhesive being heated by irradiation with microwave energy. For this, the application of the microwave energy should be localized and the microwave energy should be applied in a pulse-like manner in a first and at least a further group, the amplitude of each group being lower at the end than at the start of the group, and continuous microwave energy is applied for a period between the impulse groups. The constituents of the binding agent comprise isocyanate-functional reaction products from a stoichiometric excess of aromatic isocyanates with a polyol. Complexed amines, particularly the complex of methylenedianiline and common salt, are proposed as the heat-activatable crosslinking agents. In this document, microencapsulated polyamino or polyhydroxy functional compounds, which are consequently unavailable for reaction with the isocyanate prepolymers at room temperature, are proposed as additional crosslinking agents. These types of crosslinking agent need material temperatures above 100.degree. C., advantageously between 120 and 160.degree. C., to initiate the crosslinking reaction. [0010] A method of dispensing adhesives onto a substrate, wherein the adhesive is heated by microwave energy immediately before being dispensed onto the substrate, is described in U.S. Pat. No. 5,948,194. For this, the material is conveyed under pressure through a dispensing tube that is transparent to microwave energy. The dispensing tube is located within a microwave resonant chamber. The microwave energy is channeled from a microwave-generating source along a waveguide to the microwave resonant chamber, wherein the adhesive, on passing though the resonance chamber, undergoes negligible heating at the radial boundaries of the dispensing tube. The adhesive is subsequently dispensed onto the component along a predetermined path. The material has to be heated to different temperatures along the applied adhesive trail. General information on the compositions of adhesives that are suitable for this process is not available from this document. [0011] A method of facilitating the adhesive bonding of various components with variable frequency microwave energy is disclosed in U.S. Pat. No. 5,804,801 A. According to this document, the time required to cure a polymeric adhesive is decreased by placing components to be bonded by the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. This method provides uniform heating for various articles comprising conductive fibers. Microwave energy may be selectively oriented to enter an edge portion of an article comprising conductive fibers. Other edge portions of an article can be selectively shielded from the microwaves. Epoxy resin adhesives are disclosed as useable adhesives. [0012] Liquid, reactive, heat-curable compositions from a polyepoxide, a di or polycarboxylic acid, together with a catalyst that effects a rapid polymerization of the epoxide and anhydride mixture under microwave irradiation are described in EP 0720995 B1. [0013] A method of accelerating adhesive curing by the use of adhesive compositions that comprise nano-particles having ferromagnetic, ferrimagnetic, super paramagnetic or piezoelectric properties, that under the influence of an electric or magnetic or electromagnetic alternating field are heated up in such a way that the binding agent matrix in reactive adhesives is heated to a temperature that effects the crosslinking of the binding agent matrix through the reactive groups of the binding agent, is described in WO 02/12405. In this document, low frequency regions from about 50 kHz up to about 100 kHz are proposed as the electromagnetic radiation for heating the adhesive composition by the nano-particles. [0014] A method and a device for curing, crosslinking and/or drying coating materials and/or substrates, and a novel use of a microwave oven that is characterized by the use of microwaves with at least two wavelengths, is described in EP 1327844 A2. BRIEF SUMMARY OF THE INVENTION [0015] The present invention provides a process for curing one-component adhesive/sealing compositions that cure by means of microwave radiation. More specifically, the subject of the present invention relates to a process for curing one-component adhesives/sealants comprising surface-deactivated polyisocyanates that are solid at room temperature by means of microwave radiation, and which is furnished in such a way that the adhesive/sealant composition is macroscopically heated only to a temperature below the thickening temperature. DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS OF THE INVENTION [0016] In the context of this invention, the "thickening temperature" is the temperature to which a room temperature, shelf stable composition that comprises a surface deactivated isocyanate must be heated for a short time, that is up to an hour, in order to produce a polyaddition reaction and hence crosslinking. The polyaddition reaction and/or crosslinking is recognized by a significant "thickening", i.e., by the solidification of the material. In the context of this invention, the thickening temperature can be determined by placing the composition to be tested in an oven at a predetermined temperature and measuring the consistency of the composition as a function of time and temperature. A further possibility is to apply a trail of material onto a Kofler heating plate, i.e., a surface that exhibits a specified temperature gradient. In this way, the thickening temperature can be defined as the frontier between pasty and crosslinked material. The simplest method of determination is a viscosity measurement at defined increasing temperatures of the measurement plate. In this case the thickening temperature is defined as the value that can be read after initiation of the curing reaction by extending the almost vertically rising branch of the viscosity curve onto the temperature axis. [0017] The "material temperature" of the adhesive/sealant composition that is heated by microwave radiation according to the inventive process is understood to mean the temperature measured at the surface of the composition of the horizontal adhesive trails (1 cm wide, 0.5 cm high) immediately after they have left the microwave radiation. [0018] In a preferred embodiment of the process according to the invention, the microwave radiation impinging on the adhesive composition is controlled such that, in the sense of the above definition, material temperatures between 40.degree. C. and 120.degree. C. are attained, the material temperature being preferably between 50 and 70.degree. C. [0019] In the context of this invention, "microwaves" are understood to mean electromagnetic radiation in the frequency range between 300 MHz and 300 GHz, i.e., electromagnetic rays between the high frequency region of radio waves and infrared radiation. In particular, the "microwave radiation" region in the context of this invention includes the regions of decimeter waves with frequencies between 300 MHz and 3 GHz and the centimeter waves with frequencies between 3 GHz and 30 GHz and may, however, also include the region of millimeter waves between 30 GHz and 300 GHz. 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