DE3810096A1 - METHOD FOR CONNECTING TWO SUBSTRATES AND COMPOSITIONS SUITABLE THEREOF - Google Patents

Abstract

Novel processes for bonding a transparent polycarbonate substrate to another polycarbonate substrate employ a visible light curable ashesive composition consisting essentially of: (1) one or more polyfunctional acrylic monomers; (2) an elastomer (e.g. an acrylic rubber or chlorosulphonated polyethylene rubber) or a polyfunctional aliphatic urethane acrylate polymer or oligomer; and (3) a catalyst or photoinitiator activatable by visible light. Such a process can be used for binding or sealing polycarbonate vehicle headlamp assemblies

Description

The present invention relates to the art of Connecting a transparent polycarbonate part with a another polycarbonate substrate (which may be transparent or not).

Since the invention in particular the task of connecting or sealing polycarbonate vehicle headlights As far as arrangements are concerned, it will be discussed in detail below Related to this.

Automotive headlight assemblies consist in the general of two parts: a headlamp housing, in which the lamps are and a transparent one Front cover. The seam between the transpa pensions cover and the housing must have rigid requirements generally considered as stability against weather and normal use and environmental conditions (apart from Collisions) during the life of the vehicle can be described.  

In the development of material selection for such Headlamp arrangements, it has now become common, the to produce both components from polycarbonates. While the front cover is of course transparent is the case is opaque, with the inside a reflective coating for increased luminosity having.

So far, such headlight assemblies are in general connected by one of two methods or welded: (1) by a thermosetting Two-component urethane adhesive or (2) by vibration welding. In the former method, the Mixed two-component urethane composition and applied, the parts are assembled and the The arrangement obtained is then passed through an oven during a Time span and at a temperature led to the curing to effect. In the vibration welding system, the assembled parts exposed to vibration, e.g. Sound vibrations to melt the surfaces and weld together.

Both systems require capital investment for the necessary Equipment. Furthermore, the vibration welding technology in its scope by the geometric shape of the limited parts to be assembled. More important is that none of the systems is sufficiently fast to handle the Processing needs in an automotive assembly factory completely satisfy.

For these reasons there is a great need in the Automotive industry after a system with which Polycar bonat headlight assemblies faster and with less Capital costs and equipment.  

According to the invention, the above-mentioned problem is solved in elegant and most effective way by using the photocurable compositions which are described in the following individual are described.

Photopolymerization or radiation curing, as they are sometimes called is well known. She was in literature is referred to as "the silent revolution". From modest beginnings in the early 70s when she mainly in printing, papermaking and the Filling and coating of flat wood products used has become, this "silent revolution" in the technology in transformed a lively field of literature full of patent literature. In recent years, this revolution has become technology in the electronics industry, e.g. for photoresistors and Connectors and for encapsulating components and Welding of printed circuit boards, as well as in the areas of Colors, fiber optics, jewelery making and dental and medical applications spreads. Today, radiation-cured inks, Beschich materials and adhesives in objects as diverse as Furniture, soda cans, plastic containers, microchips and found many other products.

Of the four known to those skilled in the main types of Radiation curing, namely ultraviolet (UV) curing, Electron Beam Hardening (EB), Infrared Curing (IR) and Hartung with visible light (VL), UV and EB have the market dominated, with UV prevailing. For example in the early 80's UV curing was about 85% the radiation-cured applications found. EB, a System with relatively high capital costs, was the cure medium in almost all remaining applications, esp especially for thicker, heavily pigmented coatings. IR cure, which was first developed, is near  completely replaced by UV. Very recently has used visible light curing applications, mainly in such areas as dentures and Dental fillings.

In general, the purpose behind the development of the Radiation hardening that one the need of solution and furnaces and the like for the removal of these Wanted to eliminate solvents. Radiation-cured inks, Coatings and adhesives were opposite corresponding solvent-based products, i.e. they were cheaper, faster and safer. Mainly to these benefits is the "silent revolution" attributed in the art.

Typically, radiation-curable compositions contain tongues, e.g. Adhesive compositions at least one suitable polymer or oligomer, a photoinitiator and a liquid monomer in which the various others Components are soluble, wherein the monomer with the polymer in the presence of curing actinic radiation, which, like mentioned, in most applications is UV light, is networkable. In general and regardless of the Hardening radiation source used are the liquid Composition characterized in that they are solvent-free and have an excellent stock owning balance, i. that in the absence of the hardening Radiation can be stored for long periods of time.

The liquid monomers heretofore used in radiation-curable compositions have been proposed, include both mono- and polyfunctional monomers Materials. A mixture of mono- and polyfunctional Monomers provide a useful way to the degree of hardness to change the cured composition.  

As examples of monomers used so far may be mentioned: butanediol dimethyl acrylate, Butoxyethylmeth acrylate, butyl methacrylate, diethylaminoethyl methacrylate, Diethylenglykoldimethylacrylat, Dimethylaminoethylmeth acrylate, ethylene glycol dimethacrylate, 2-Ethylhexylmeth acrylate, ethoxyethyl methacrylate, glycidyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, methyl methacrylate, Neopentylglykoldimethacrylat, poly ethylene glycol dimethacrylate, tert-Butylaminoethylmeth acrylate, triethylene glycol dimethacrylate, tetrahydrofufuryl methacrylate and trimethylolpropane trimethacrylate. Other monomers which may be used include acrylates such as butylene glycol diacrylate, n-butyl acrylate, diethylaminoethyl acrylate, 1- ethylhexyl acrylate, ethoxyethyl acrylate, hexane diol diacrylate, polyethylene glycol diacrylate, phenoxyethyl acrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate, triethylene glycol diacrylate, etc .; Acrylamides such as N-isobutyloxymethylacrylamide, N-methylolacrylamide, NN-dimethylacrylamide, N, N-methylene-bis-acrylamide, etc .; Allyl monomers such as allyl glycidyl ether, allyl methacrylate, diallyl phthalate, etc .; and various other monomers known to those skilled in the art, including vinyl monomers, glycidyl ethers, and the like.

The list of useful resins and oligomers includes: Epoxy acrylate resins, oligoester acrylates, unsaturated Polyester, urethane-acrylic compounds, polymethylstyrene, Styrene-malea resins, unsaturated polybutadiene with hydroxy end groups, resins derived from tall oil and tree resin, liquid polyamides, unsaturated alkyd compounds, Phenolic compounds, vinyl esters, bisphenol type polyesters, halogenated polyesters, furan resins and the like.  

The used photoinitiators change depending on from the radiation source for curing. In typical UV systems can be the monomethyl ether of benzoin or a higher alkyl benzoin ethers as activator with or without Peroxide polymerization catalyst can be used. The Absorption of UV radiation causes the ether in free radicals breaks down, which then becomes the polymerization breaker start. On the other hand, at by Visible light activated products usually camphor quinone in combination with an organic amine, e.g. With N, N-dimethylaminoethyl methacrylate used. The diketone absorbs radiation in the range of 420 to 460 nm and goes in an excited triplet state over, along with the amine leads to ion radicals.

Although not intended to be exhaustive, it serves the above overview but to illustrate the extensive state of the Tecknik concerning the Photopoly and the long list of suitable monomers, resins and oligomers available to the polymer chemist, which wants to formulate a polymerizable composition.

As already mentioned, there are many in the patent literature various radiation curable compositions beschrie ben, including combinations of polymers and Monomers used in such compositions can be. The following patents are exemplary of the state of the art.

The US-PS 40 73 777 contains a detailed description of unsaturated, water-dispersible polyester adhesive fabrics, foils and textile finishes.  

The US-PS 40 82 710 relates to certain isocyanate modified compounds resulting from the reaction products from an organic isocyanate with compounds having a Variety of acrylic residues exist, these by Isocyanate-modified compounds in the presence of visible or can be polymerized by UV light. You can either singly or mixed with others Materials such as inert, non-copolymerizable Polymers, reactive copolymerizable polymers, copolymerizable oligomers, interten plasticizers, interten organic solvents, copolymerizable olefinically unsaturated monomer compounds and various which additives are used.

US-PS 41 81 752 relates to pressure-sensitive adhesives, which can be obtained by using a solvent-free, radiation-sensitive, acrylate-containing, polymerizable Mass of radiation near the UV range exposes. There are methods for the free radical Polymeri sation of an acrylate in the presence of UV, and Although an acrylic acid ester, an alkanol and a Monomers such as acrylic acid, methacrylic acid, acrylamide, Acrylonitrile, methacrylonitrile, N-substituted acrylamides, Hydroxyacrylates, N-vinylpyrrolidone, maleic anhydride and Itaconic acid.

The US-PS 42 06 025 relates to certain acrylic polyesters, the can be cured by UV or EB. These polyesters are described as polymerizable organic Compounds obtained by polyesterification of dicarboxylic acids with a stoichiometric excess of OH groups of di- and polyhydric alcohols are obtained, the excess hydroxy groups subsequently with acrylic acid or one of their functional derivatives.  

US Pat. No. 4,530,746 relates to photopolymerizable resin compositions comprising a monomer, for example a vinyl-endcapped monomer which exhibits slight shrinkage upon polymerization. In detail, the compositions described contain: (a) the abovementioned monomer, (b) at least one epoxy acrylate, 1,2-polybutadiene, polyester or organopoly siloxane resin having one or more acryloyloxy groups or methacryloyloxy groups at their molecular end or molecular ends and (d) a photoinitiator.

In US-PS 45 33 446 is an anaerobic adhesive together described by UV or visible radiation is activatable and contains the following components: (a) a anaerobically polymerizable acrylate ester monomer, (b) a Compound, which under the influence of ultraviolet or decays visible light and releases a strong acid, (c) a free radical peroxy starter and (d) a Activator for anaerobic polymerization, in the presence a strong acid with the peroxide starter reacts to the Catalyze polymerization of the monomer.

As already mentioned, they have visible light hardenable adhesives industrial application mainly in Dentistry, for example, for dentures and Fillings found. In general, these are Compositions one or more methacrylic monomers, a or more oligomers and, of course, the photoinformation system used. As an example of related patents, the U.S. Patent Nos. 4,407,984, 4,439,380, 4,459,193, 4,525,256, 45 63 153 and 45 81 389 are called.

According to the invention, the object is achieved by the use of a visible light curable adhesive composition dissolved, consisting essentially of the following components  consists of: (1) one or more polyfunctional ones Acrylic monomers, (2) a high molecular weight polymer weight, for example an elastomer, which is substantially is not reactive in the composition and serves increase their viscosity and further as shock modes fizierer and to improve the flexibility of the hardened adhesive is used, or alternatively a polyfunk tional aliphatic urethane acrylate polymer and (3) a Catalyst or photoinitiator caused by visible light is activatable.

The invention will be explained in more detail with reference to a figure which an exploded view of an exemplary automobile Headlight arrangement is what the present Invention in particular.

As already mentioned, the present invention relates to the technique of bonding a transparent polycarbonate substrates with another polycarbonate substrate. In particular, it relates to an improved adhesive system for the creation of automobile headlight assemblies Polycarbonate.

During processing, the headlamp assemblies exist from two essential components, namely a housing for the headlight and a transparent front cover or Plate through which the light from the headlight in Housing passes out. These two components need then be joined together tightly in a way that sufficient to meet the rigid requirements of Be set up by car manufacturers, these being Requirements in turn dictated by environmental conditions who are involved in the operation of this headlight vehicle are connected.  

At present there are essentially two different ones Systems in commercial production for the fulfillment of necessary standards for the stability of use of Arrangement.

The first system uses a thermosetting two-core components-urethane adhesive. During processing, the Two-component adhesive mixed and applied to one or both applied to bonding surfaces, and then the respective surfaces brought into contact with each other to complete the arrangement. The headlight anord tion is then fed into an oven, which at a Temperature is operated with a residence time, the sufficient to provide an adhesive bond. Although is this adhesive system in terms of the quality of completely satisfactory, but it does nevertheless suffers from the processing under certain Deficiencies, among which the main ones for finishing is the time required for the connection seam. To the others Disadvantages include the energy consumption and the furnace required factory space. The above can be of course, in a cost factor for automobile assembly translate factories.

The second system for the production of headlamp Anord tions uses the known as vibration welding Technology in which the parts are assembled and one Vibration be subjected, for example, sonic Schwin conditions to melt and join the surfaces together welding. This system also requires time and energy. In addition, the vibration welding causes neces tensions and weakening of the connected Range.  

As a result, has long been in the automotive industry Needed to find an adhesive that creates the required seam in seconds and ideally without stoves and similar energy and platzver equipment needed.

For such an adhesive to be useful, it must, as above determined to meet certain rigid requirements. Around To meet this standard, he must have the following physika possess the following characteristics:

• (1) Shear bond strength at 23 ° C - a bond strength of 9,60 N / mm ² (1393 psi) or destruction of the substrate;
• (2) Shear bond strength at -29 ° C; a bond strength of 9,60 N / mm ² (1393 psi) or destruction of the substrate; and
• (3) Creep resistance at 88 ° C - after 24 hours it may do not slip.

In addition to these functional features, everyone should Adhesive that is for commercial use is provided for the headlamp assembly, too transparent and otherwise harmless and aesthetic be acceptable.

To the transition in the production of one of the two as described above, functionally acceptable systems justify that currently used in production A new adhesive system should be meaningful Offer processing advantages, such as the main abandonment of a significant reduction in production time for mass production of the arrangements.  

According to the invention, the above object is achieved with a new visible light curable adhesive solved.

As explained above, are photopolymerizable Adhesive compositions known in the art. however refers to the vast majority of the prior art on UV curing, used for the compound of polycarbonate, the considered here is not suitable, and because of the fact that the polycarbonates are not sufficient are transparent to UV light and that, although they are for light are transparent within the visible spectrum. Conversely, although the curable by visible light Adhesives have become known in recent years but their industrial application is in the essentially on dental filling materials and denture materials limited. In these dental applications Methacrylates are used, and methacrylates as Material class does not cure sufficiently fast to the Objectives of the present invention fully meet.

Consequently, it can be said that the present invention is a new use for curable by visible light Adhesive compositions, as well as certain Compositions of this kind which are useful for bonding Polycarbonates in general and for the production of Polycarbonate headlight assemblies in particular suitable are.

The novel compositions according to the invention consist in consisting essentially of: (1) one or more polyfunctional ones Acrylic monomers, (2) one or more of the above described polymers and (3) one by visible light activatable catalyst or photoinformation system. If necessary, it should be remembered that these together  contain small amounts of other materials can. So while the above materials the components can be as much as 10 % By weight of additional monomers and / or polymers incorporated if deemed desirable or appropriate becomes. (Somewhat larger amounts than 15% by weight are not been tested, but it is believed that too goes).

As examples of useful polyfunctional acrylic monomers The following compounds may be mentioned: 1,6-hexane diol diacrylate, tripropylene glycol diacrylate, trimethylol propane triacrylate, tetraethylene glycol diacrylate, penta erythritol triacrylate, butylene glycol diacrylate, triethylene glycol diacrylate, etc. For headlight assemblies 1,6-hexanediol diacrylate is preferred and has therefore been used for the most extensive test selected.

As indicated, useful polymers are not reactive elastomers, i. rubbery compounds that do not react with the acrylic monomer during cure, and polyfunctional aliphatic urethane acrylate polymers, who react with it. If they are used, then cause the rubbery compounds or elastomers a Increase the viscosity to a manageable level, and they act as impact modifiers and improve the Flexibility of the cured adhesive. A usable one Class of elastomer are those materials that the Those skilled in the art are known as polyacrylic gums and sometimes be referred to as acrylic elastomers. As examples of Materials of this kind can be called: "Hycar" (Trademark of B.F. Goodrich Company), a class of "chemically saturated" rubbers made from acrylic acid esters, with Hycar 4051CG being particularly preferred broken white plate form, high polymer, specific  Weight = 1.10, Mooney viscosity, ML-1 + 4 minutes, 100 ° C = 25-40, solution viscosity 20% in MEK (unground) LVF Brookfield viscosity = 6000 max.

Another useful class of elastomer that the above to provide the stated effects are the synthetic chlorosulfonated polyethylene rubbers such as "Hypalon" (Waren sign of DuPont), white chips, specific weight 1.14, Mooney viscosity ML = 1 + 4 at 100 ° C = 28.

It is also contemplated that reactive elastomers can be used, for example, those of "Kraton G" series (trademark of Shell Chemical Company for a series of mainly triplets called as Two-phase polymers are characterized by polystyrene in a rubbery polyethylene-butylene matrix consist) .

As examples of polyfunctional aliphatic urethane acrylates, which are used as a polymer component can be called: "Chemlink" (Trademark of Sartomer Company for a group of aliphatic Urethane acrylate oligomers), e.g. Chemlink 9504, specific Weight at 25 ° C = 1.17, viscosity, mPa.s, 21 ° C = 167 000, 38 ° C = 10,500, 60 ° C = 3250, and Chemlink 9505, specific Weight = 1.20, viscosity, 38 ° C = 145,000, 60 ° C = 35,000; CMD 8800 (trade name of Celanese), not one volatile acrylated urethane based on aliphatic, Isocyanate, specific gravity = 1.05, viscosity, 25 ° C semi-solid, 65 ° C = 9800 mPa.s, which according to the Celanese Product information 10% of the monomer ethoxyethyl acrylate contains; etc.  

It can be seen that if one is an unreactive Polymer uses, for example, an elastomer, as above described, the adhesive formed after curing a mixture of this polymer and the one through the Polymerization of the monomer or monomers used in the hardenable composition are contained, obtained polymer contains. On the other hand, if a polyfunctional polymer, as described above, then The cured adhesive contains a copolymer from this polymer and the monomer or monomers in the curable composition.

The visible light curable system can be used for this purpose reagents known to those skilled in the art as those which do not form part of the invention. A particularly useful, as such known system for Catalysis of the polymerization in the presence of visible Light comprises a mixture of camphorquinone (d-2,3-bornane dione) and an organic amine, preferably N, N-dimethyl aminoethyl). In general, the catalyst combination in a ratio of the order of 1:10 camphorquinone: amine are used, although the Ratio can be changed.

The ratios of polymer to monomer in the above mentioned compositions may vary and not exactly be quantified. Generally speaking, essential lower levels of the high molecular weight elastomer used as of the alternative difunctional aliphatic urethane acrylate polymer.

For example, a manageable viscosity of curable composition (viscosity suitable for use the formulations without excessive flow) in the range of 2000 to 20,000 mPa.s (cps) are. To this viscosity too  achieve the minimum ratio of elastomer: mono mer (en) in the order of 1:10. Big amount of Of course, elastomers can be used, with the Upper limit by the selected area for handling Viscosity is given.

When the above-mentioned polyfunctional polymer is used, then larger quantities are used than they have been mentioned above. For example, the Range for polymer: monomer in the order of 1: 1 to about 7: 3, by weight, are.

It is clear that the compositions of the invention before for use in an opaque environment must be kept. When they are packed in the dark or stored, they have an excellent Storage stability.

Curing can be done with any light source including ordinary room lighting causes the visible Radiation provides, e.g. with a wavelength of 460 nm. Preferably, however, the cure becomes high causes intense blue light source, for example with a lamp that is on the order of 30 watts / 25.4 mm Energy emitted between 400 and 470 nm. Sources for visible light of this type are commercially available and So known to the expert.

The invention curable by visible light Compositions have sufficient viscosity, for example, between 2000 and 45,000 mPa.s (cps), so that they can be applied without "running away". You can applied by any known method, e.g. by coating, brushing, with a syringe or a other instrument. When she's upset and the visible  Light are exposed as curing radiation, then they are characterized by a rapid initial gelation, for example, in a few seconds, and a full one Curing may take less than 10 seconds after exposure obtained against the curing radiation.

In contrast, methacrylic compounds require as Class, for example, those as dental adhesive be used, much longer curing times, for example wise on the order of 120 seconds. These longer ones Hardening times are for uses that fiction to be envisaged, unsatisfactory.

In the following the invention will become more apparent by way of examples explained.

example 1

19.0 kg of Hycar 4051CG were mixed in a 68.8 kg 1,6-hexanediol diacrylate and 10.0 kg ethoxyethoxyethyl acrylate at a temperature of 45 ° C by mixing for about 5 Hours completely dissolved. While maintaining the Temperature were added to 200.0 g of camphor quinone and the resulting mixture was stirred for about two hours until the resolution was complete. Then, 2.0 kg of N, N-di methylaminomethacrylate was added and the mixture became a Stirred in the dark for an hour, one through visible Light curable adhesive composition with a Brook field viscosity of 40 000 mPa.s at 25 ° C, the the following ratio of constituents:

Wt .-% Hycar 4051 CG 19.0 1-6-hexanediol diacrylate 68.8 ethoxyethoxyethyl 10.0 camphorquinone 0.2 N, N-dimethylaminoethyl 2.0

Similarly, the following were added Compositions made:

Example 2 Wt .-% Chemlink 9505 68.6 1-6-hexanediol diacrylate 29.2 camphorquinone 0.2 N, N-dimethylaminoethyl 2.0

Example 3 Wt .-% Chemlink 9504 68.6 1,6-hexanediol diacrylate 29.2 camphorquinone 0.2 N, N-dimethylaminoethyl 2.0

Example 4 Wt .-% CMD 8800 55.9 1,6-hexanediol diacrylate 35.7 ethoxyethoxyethyl 6.2 camphorquinone 0.2 N, N-dimethylaminoethyl 2.0

Example 5 Wt .-% Hypalon-30 19.15 1,6-hexanediol diacrylate 76.65 camphorquinone 1.0 N, N-dimethylaminoethyl 3.2

Example 6 Wt .-% Hypalon-30 19.6 1,6-hexanediol diacrylate 78.2 camphorquinone 0.2 N, N-dimethylaminoethyl 2.0

(For the sake of accuracy, it should be noted that the polymer component in each of Examples 2 to 4 a had waxy consistency and therefore melted had, for example, at 50 ° C in an oven before you could try to mix it up.)

Example 7 Wt .-% Hypalon-30 19.8 1,6-hexanediol diacrylate 79.05 camphorquinone 0.15 N, N-dimethylaminoethyl 1.0

The new adhesives of the invention are in general characterized in that they have high seam shear test values and deliver very good shock test results. They deliver a lot strong adhesive bonds on polycarbonates (and also on Polymethyl methacrylate substrates). You are still by it characterized in that they have good breaking strength, chemical and Moisture resistance as well as excellent Resistance to temperature changes and show mechanical abrasion.

While it has been described above that they have great utility for bonding a polycarbonate surface of a transparent article to another polycarbonate substrate, it is of particular interest in the present invention to tightly seal polycarbonate headlamp assemblies within a few seconds in a manner very close to one another meets strict test criteria. The figure illustrates a typical headlight assembly. As shown therein, the headlamp assembly includes a transparent front cover 10 and a headlamp housing 12 . The front cover 10 has a flange 14 extending around its inner periphery and a side 16 which is naturally transparent, and preferably has a surface which refracts and maximizes the radiation of the light emitted by the headlamp. It is shown that the housing 12 has the following features: a pair of central openings 18 in its inner surface 20 , in which the headlamps are arranged and through which the bases of the lamps extend outwardly to the electric booster contact; an outer surface 22 that determines the dimensions of the housing; and a grooved leading edge portion 24 which fits onto the flange 14 of the front cover. Typically, the inner surface 20 of the housing includes a reflective metal coating to increase the efficiency of the headlamp.

To seal the headlamp assembly in accordance with the present invention, a quantity of adhesive is first placed substantially uniformly across the groove 24 . The flange 14 is then inserted into the adhesive-containing groove to bring the two components into coincidence, and visible light is applied for a time and with some intensity to initiate the photopolymerization and subsequent adhesive formation and to seal the two parts together , This can be achieved in less than 10 seconds after exposure to a high intensity blue light source as described above.

Headlights of the type shown in the figure were each with the compositions of Examples 1 to 7 tight connected and tested. The test results and, so far applicable, the manufacturer's specifications, are in Table 1 shown.  

Table 1

In the above description it was mentioned that transparent polycarbonate parts (e.g., the windscreen of in the figure shown headlight assembly) with a other polycarbonate substrate (e.g., the headlight housing) combines. It should be noted, however, that the respective polycarbonate substrates do not have surfaces of Must be parts that consist only of polycarbonates. The Parts to be joined may include laminates of various types Materials instead of a single layer or one be formed part of polycarbonate. The only criterion for the applicability of the present invention is that at least one of the two parts for visible radiation is transparent to allow the hardening, and that the respective surfaces to be joined polycarbonate consist.

While in the foregoing description throughout the Connecting polycarbonate with polycarbonate referred can, as already mentioned, also very strong Bindings between Polymethylmethacrylatsubstraten obtained become. The invention thus relates in its most general Version the compound of polycarbonate and / or poly methylmethacrylate substrates with each other.

Because it is possible to make certain changes without the The scope of the present invention will be understood noted that all information in the attached drawing and the above description including the Examples are for illustrative purposes only and not in can be interpreted in a restrictive sense.

Claims (36)

1. A method for bonding two substrates, each consisting of polycarbonate or polymethyl methacrylate, wherein at least one of the substrates of the other is transparent to visible light, characterized in that (1) the substrates to be bonded with a curable by visible light adhesive A composition comprising substantially (a) at least one polyfunctional acrylic monomer, (b) a polymer selected from the group consisting of elastomers and polyfunctional aliphatic urethane acrylates, and (c) a visible light activatable catalyst or photo-initiator system for initiating cure and adhesive formation and (2) thereafter exposing the composition to visible light to form the adhesive thereby bonding the respective substrates together. 2. The method according to claim 1, characterized in that one uses a substrate made of polycarbonate. 3. The method according to claim 2, characterized in that one uses as an elastomer polymer, which in essential in the composition is not reactive, wherein the elastomer is used in an amount that is sufficient to increase the viscosity of the composition increase. 4. The method according to claim 3, characterized in that one elastomer and monomer in a minimum weight Ratio of elastomer to monomer of about 1:10 starts.   5. The method according to claim 3, characterized in that to use an elastomer that is from the group consisting of polyacrylic rubber and synthetic chlorosulfonated polyethylene rubbers is selected. 6. The method according to claim 5, characterized in that is used as the monomer 1,6-hexanediol diacrylate. 7. The method according to claim 3, characterized in that one in the composition of the other not more than about 10 wt.% of an additional monomer incorporated. 8. The method according to claim 7, characterized in that Ethoxyethoxyethylacrylat as additional monomer used. 9. The method according to claim 2, characterized in that as a polymer is a polyfunctional aliphatic Urethane acrylate used. 10. The method according to claim 9, characterized in that one uses a polymer consisting of the group from aliphatic urethane acrylate oligomers and acrylated urethanes based on aliphatic Isocyanates is selected. 11. The method according to claim 9, characterized in that one polymer and monomer in a weight ratio of Polymer to monomer from about 1: 1 to about 7: 3. 12. The method according to claim 9, characterized in that is used as the monomer 1,6-hexanediol diacrylate.   13. Method for joining opposing surfaces of two polycarbonate parts, of which at least one permeable to visible light, thereby characterized in that (1) on the surfaces of the parts to be joined Layer of a photocurable adhesive composition consisting essentially of (a) at least one polyfunctional acrylic monomer, (b) a polymer selected from the group consisting of Elastomers and polyfunctional aliphatic Urethane acrylates and (c) visible light activatable catalyst or photoinformation system for Starting the hardening and the glue formation, and (2) the transparent part of the visible light to harden the applied layer and thereby connecting the respective parts together. 14. The method according to claim 13, characterized that is the viscosity of the curable composition to about 2,000 to about 45,000 mPa.s. 15. The method according to claim 14, characterized that 1,6-hexanediol diacrylate is used as the monomer. 16. The method according to claim 13, characterized that you use such parts that they after the Connect an automobile headlight assembly form. 17. Method of forming an automobile front-end license projector assembly of molded components, the one transparent polycarbonate cover and a poly comprising carbonate headlight housing, wherein the Components are designed so that they cover  can be brought and after connecting the Front headlight assembly represent, thereby characterized in that (1) on the surface of at least one of the components to be connected Layer of a photocurable adhesive composition consisting essentially of (a) at least one polyfunctional acrylic monomer, (b) a polymer selected from the group consisting of Elastomers and polyfunctional aliphatic Urethane acrylates and (c) visible light activatable catalyst or photoinformation system for Starting the hardening and adhesive formation, (2) the components to be assembled brings, with each of the surfaces to be joined with opposite sides of the applied layer from the curable adhesive composition in contact come and (3) the applied layer of the curable Composition exposed to visible light to the To form adhesive and thereby the respective Components connect to the headlights arrangement. 18. The method according to claim 17, characterized that is the viscosity of the curable composition to about 2,000 to about 45,000 mPa.s. 19. The method according to claim 17, characterized that one uses a polymer selected from the group consisting of polyacrylic rubbers, synthetic chlorosul Polyethylene rubbers, aliphatic urethane based on acrylate oligomers and acrylated urethanes is selected from aliphatic isocyanates.   20. The method according to claim 19, characterized that 1,6-hexanediol diacrylate is used as the monomer. 21. The method according to claim 20, characterized that one uses a photo starter system, which Camphorquinone and an organic amine are included. 22. A visible light curable adhesive suitable, polycarbonate substrates to connect with each other, characterized in that the composition substantially (a) at least one polyfunctional acrylic monomer, (b) a polymer selected from the group consisting made of elastomers and polyfunctional aliphatic Urethane acrylates and (c) visible light activatable photo starter system for starting the Hardening and adhesive formation, wherein the monomer or monomers and the polymer or the polymers at least 90% by weight of the total Weight of the monomers and polymers in the together make up. 23. The composition according to claim 22, characterized gekenn characterized in that the polymer is an elastomer which is in the essential in the composition is not reactive, wherein the elastomer is present in an amount that is sufficient to increase the viscosity of the composition increase. 24. The composition according to claim 23, characterized gekenn records that the minimum weight ratio of Elastomer to monomer is about 1:10.   25. A composition according to claim 23, characterized gekenn characterized in that the viscosity of the curable composition about 2000 to about 45 000 mPa.s. 26. The composition according to claim 23, characterized characterized in that the elastomer consists of the group made of polyacrylic rubbers and synthetic chlorosulfonated Polyethylene rubbers is selected. 27. The composition according to claim 23, characterized gekenn indicates that the monomer is 1,6-hexanediol diacrylate. 28. The composition according to claim 22, characterized gekenn indicates that the polymer is a polyfunctional aliphatic urethane acrylate. 29. The composition according to claim 28, characterized gekenn characterized in that the polymer is selected from the group consisting of aliphatic urethane acrylate oligomers and acrylate urethanes based on aliphatic isocyanates is selected. 30. A composition according to claim 28, characterized gekenn characterized in that the weight ratio of polymer to Monomer is about 1: 1 to about 7: 3. 31. The composition according to claim 28, characterized gekenn indicates that the monomer is 1,6-hexanediol diacrylate. 32. The composition according to claim 28, characterized characterized in that the viscosity of the curable composition about 2000 to about 45 000 mPa.s.   33. A visible light curable adhesive setting, characterized in that it has a Viscosity of about 2000 to about 45 000 mPa.s has and essentially off (a) 1,6-hexanediol diacrylate monomer, (b) at least one polymer selected from the group consisting of polyacrylic gums, synthetic chlorosul Polyethylene rubbers, aliphatic urethane based on acrylate oligomers and acrylated urethanes of aliphatic isocyanates, wherein the monomer and the polymer or polymers at least 90% by weight of the Total weight of monomers and polymers in the Make up the composition, and (c) a visible light curable photo starter system for starting the curing and adhesive education exists. 34. A composition according to claim 33, characterized gekenn records that the photo starter system camphorquinone and an organic amine. 35. The composition according to claim 34, characterized gekenn characterized in that the amine is N, N-dimethylaminoethyl meth acrylate is. 36. A composition according to claim 33, characterized that they further ethoxyethoxyethyl contains acrylate monomer.