GB1595070A

GB1595070A - Laminated safety glass

Info

Publication number: GB1595070A
Application number: GB45089/77A
Authority: GB
Original assignee: Dynamit Nobel AG
Current assignee: Dynamit Nobel AG
Priority date: 1976-10-30
Filing date: 1977-10-28
Publication date: 1981-08-05
Also published as: AU3021277A; CA1111750A

Description

(54) LAMINATED SAFETY GLASS (71) We, DYNAMIT NOBEL AKTIENGESELLSCHAFT, a German Company, of 521 Troisdorf, near Cologne, Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to laminated safety glass and to a process for the production thereof.

The specification of our copending Patent Application No. 45356/76 (Serial No. 1503290) describes and claims a process for the manufacture of laminated safety glass comprising bonding one or more silicate sheets at a temperature of from 120 to 2000C to a plasticised polyvinylchloride, as therein defined, bonding being assisted by means of a silicon organo-functional silane as therein defined and/or a silicon functional silane as therein defined It has now been found that the novel use of the aforesaid silicon organo-functional silane and/or silicon functional silane can be extended in a more general manner in the bonding of silicate glass sheets to plastics foils. Thus, the process of the main patent application is also applicable to ethylene and/or propylene foils to be defined hereinafter.The process of the aforesaid patent application is preferably carried out by employing the silane(s) in solution in an organic solvent which may contain a lacquer binder. It has now been found that such a procedure can also be employed iwith plasticised partially acetalised polyvinylalcohol, especially polyvinylbutyral foils, as well as with the aforesaid ethylene and/or propylene polymer foils. Moreover, insofar as silane-containing lacquers may be employed, it is not essential for the silane(s) to be in solution in the lacquer solvent; when using foils of any of the three aforesaid types, it is possible for the silane(s) to be suspended in the lacquer solvent.

Thus, according to the present invention there is provided a process for the manufacture of laminated safety glass comprising bonding one or more silicate glass sheets at an elevated temperature of up to 200"C and under a superatmospheric pressure to a polyvinylchloride, as hereinafter defined, foil, an ethylene and/or propylene foil, as hereinafter defined, or a partially acetalised polyvinylalcohol foil, bonding being assisted by means of a silicon organo-functional silane as hereinafter defined and/or a silicon or functional silane as hereinafter defined, with the provisos that when a said polyvinylchloride foil is employed, the silicon organo-functional silane and/or silicon functional silane is applied to the surface of said foil and/or to a said glass sheet dispersed in a lacquer and that when a partially acetalised polyvinylalcohol foil is used, the silicon organo-functional silane and/or silicon functiona] silane is applied to the surface of said foil and/or to a said glass sheet dissolved in a solvent and/or dispersed in a lacquer, a solvent, when used, being removed after the application to the foil and/or glass sheet surface.

The process of this invention can be carried out at autoclave temperatures as high as 175 to 2000 C. The minimum bonding temperature employed will usually be 1200C and autoclave temperatures of 120 to 1500 are preferably used, the autoclave temperatures being more preferably from 135 to 1450 C.

As is acknowledged in the specification of the aforesaid copending patent applica tion, it has been known for some time to use bi-functional silanes for improving the bond strength obtained between synthetic resins and inorganic substrates. The silanes have been employed, inter alia, in filled or strengthened synthetic plastics materials, sealing compositions, cements and lacquers. With all the hitherto proposed systems, the silane serves to improve or largely maintain an existing bond in such manner that it will be maintained even when subject to the action of moisture or when stored in water.

In contrast thereto, silanes are used in the present invention to form a bond between a plastics foil and glass which would not exist but for the use of the silane.

Particularly insofar as the use of partially acetalised polyvinylalcohol foils is contemplated herein, it is of interest that German Offenlegungsschrift No. 2,410,153 proposes the use of silanes in conjunction with polyvinyl butyral foils in the production of laminated safety glass. In this case, however, the silane serves to reduce the already high glass adhesion thereby making the foils easier to work with and is employed in predetermined quantities in the polyvinyl butyral before or during the processing thereof to form a foil. The silane is admixed with synthetic resin in a separate processing step. It is found to be uniformly distributed over the entire resin and accordingly relatively large amount sof silane have to be employed.It contrast, as will be shown hereinafter, when using partially acetalised polyvinylalcohol foils, in the process of this invention, and at least equally good effect is produced if only the surface of the layers to be bonded are treated with the silane(s), this treatment being carried out in solution or dispersion form using considerably smaller amounts of silane(s) than those which are required when working in accordance with the procedure of German Offenlegnngsschrift No. 2,410,153.

The use of silane(s) in solution or suspension applied to the surfaces to be bonded has a further advantage that the influence of the water content of the acetalised polyvinylalcohol foil no longer affects the adhesion of the foil to glass to any significant extent. It has been found, in general, that the adhesive capacity of acetalised polyvinyl alcohol foils with respect to glass decreases as the water content of the foils increases. By reducing the water content, on the other hand, the adhesive capacity is generally increased. By treating the surfaces of such foils with solutions or suspensions of silanes which increase the bond strength, reliable long-term adhesion is obtained over a wide range of water contents in the foil up to high water contents.In contrast, treatment with silanes which have the effect of reducing adhesive capacity will result in the achievement of reliable long-term adhesion over a wide range down to low water contents.

Furthermore, the value of plasticised polyvinylbutyral foils in the building industry in connection with the production of glass panes for windows has been appreciated for a considerable time because of the high adhesion of such foils to glass. When sheets of laminated safety glass are used as windscreens in motor vehicles, the adhesion of the foil to the glass must, in contrast, be suitably reduced. If in fact the screen is destroyed by impact, then when high adhesion of foil to glass occurs, penetration at the centre of impact occurs without much glass splintering. With poor adhesion, the impacting agent, for example a falling body, is in fact elastically taken up by the foil, but the splintering or shattering is very great.In the event of a collision when the windscreen is destroyed by impact of the head, the foil should undergo expansion to slowly break down the kinetic energy of the head falling thereon and moreover the destroyed glass should still adhere sufficiently well to the foil so that dangerous injury by cuts is avoided. For this reason, the power of adhesion in these cases must be adjusted to a defined pummel value (see hereinafter) range, which is generally from 2 to 5. Such behaviour can readily be achieved when utilising partially acetalised polyvinylalcohol foils in the process of the invention.

Foils used in the process of this invention will preferably have Shore-A hardnesses, measured in accordance with DIN 53505 of from 40 to 98, preferably from 50 to 95. The foils generally achieve such softness by the plasticisation thereof, whether by internal plasticisation using plasticising comonomers in the production of the foilforming polymers, or by use of separately added plasticisers. In general, some plasticisa'tion is required and references herein to foil should always be considered to imply that plasticisation thereof has occurred.

The expression "ethylene and/or propylene foil" is used herein to denote a foil formed from a polymer which is a homopolymer of ethylene or propylene or a copolymer of ethylene and/or propylene with at least one comonomer, the copolymer having a monomer content of more than 30% by weight of ethylene and/or propylene, the remainder, up to 100%, being formed of comonomers which are copolymerisable with ethylene and/or propylene. A plasticising comonomer which may be used with ethylene and/or propylene is vinyl acetate. As compared with the plasticised partially acetalised polyvinylalcohol foils hitherto employed as adhesive foils between glass sheets, such copolymers with vinyl acetate have the advantage that they are substantially more cold resistant with respect to impact.

Other co-monomers which may be employed in the production of ethylene and/or propylene copolymers are olefinically unsaturated compounds, for example butadiene, alkylvinyl ethers, vinylchloride, vinyl fluoride, acrylic acid, acrylic acid esters, for example ethylacrylate and butylacrylate, maleic anhydride, maleic acid esters and styrene which may be used singly or in admixture. Reaction products of these copolymers, which are for example formed by hydrolysis reactions or neutralisation reactions with bases so that metal irons are introduced thereinto.

The term "polyvinylchloride" is used herein in a broad sense, unless otherwise indicated, to mean homopolymers, copolymers with one or more olefinically unsaturated monomers and graft polymers of vinylchloride as well as reaction products thereof.

Preferred polyvinylchlorides for use in the process of this invention are poly vinylchlorides with a K-value of from 50 to 80, more preferably frdm 60 to 75. In addition to homopolymers of vinylchloride, it is possible to use copolymers of vinyl chloride with other ethylenically unsaturated hydrocarbons, for example ethylene, propylene, isobutylene, 2-methyl-but-2-ene, butadiene and styrene; ethylenically un saturated halogenated hydrocarbons, for example vinyl fluoride, tetrafluoroethylene and other relatively high fluorinated olefines, vinylidene chloride, trichloroethylene, 2-chloro-prop-1-ene and other chlorinated higher olefines, halogenated butadienes, halostyrenes; ethylenically unsaturated alcohols and ethers, for example vinyl alcohol, vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether and other higher vinyl alkyl ethers, halogenated vinyl alkyl ethers, allyl glycidyl ethers; ethylenically unsaturated acids and acid derivatives, for example vinyl acetate, vinyl stearate, vinyl oleate and other vinyl esters of higher fatty acids, vinyl esters of alkoxy acids, allyl esters, methyl or ethyl esters of acrylic acid, acrylic esters of higher alcohols, acrylonitrile, meth acrylic acid esters, olefine-dicarboxylic acids and their esters; and ethylenically un saturated compounds which contain hetero atoms such as nitrogen, phosphorus, sulphur or tin. Copolymers of vinyl chloride and two or more such monomers can also be used.It is also possible to use graft polymers of vinylchloride, reaction products, in particular chlorination products, of homopolymerised vinylchloride or of the copolymers or graft polymers of vinylchloride as aforesaid, one such reaction product being post chlorinated polyvinylchloride, or mixtures of such polymers derived from vinylchloride with each other or even with polyvinylidene chloride.

Especially suitable for use in the practice of this invention are those foils which contain polyvinylchloride and which contain polymers miscible with the latter prefer ably present in an amount of not more than 50% by weight and not produced from vinylchloride. Examples of such polymers are polyvinyl acetate, copolymers of vinyl acetate and ethylene, acrylonitrile-butadiene-styrene polymers and methacrylo nitrile-butadiene styrene polymers.

Examples of external plasticisers which may be used in the ethylene and/or propylene foils or polyvinylchloride foils utilised in the process of this invention are esters of phthalic acid, more particular dioctyl phthalate, esters of aliphatic dicarboxylic acids, especially of sebacic or adipic acids, esters of phosphoric acid, particularly trioctyl phosphate and polymer plasticisers, in particular those based on butadiene, acrylonitrile, styrene and polyester.

In one working procedure embodying this invention applicable to the use of ethylene and/or propylene foils and partially acetalised polyvinyl alcohol foils, the the adhesion-promoting silanes are dissolved in solvents, and the solution which is obtained is applied by dipping, spraying or similar simple methods, to at least one of the relevant boundary surfaces. After the application of the solution, the solvent is preferably removed prior to the bringing together for bonding of the separate layers.

In a particular preferred procedure, the silanes are applied to at least one of the boundary surfaces of layers to be bonded, for example the plastics foil, by guiding the foil through a solution of the silane. The silane solution will contain the silane(s) in suitable concentration. Thereafter the solvent is evaporated off. When it is the foils which are treated in this way, they are not tacky and are capable of being handled in the same way as untreated foils. It is, however, also possible for the silicate glass sheets to be treated with the silane solution. In such a case, there is the disadvantage that, after the vaporisation of the solvent, the the silane(s) will remain as a moist film on the surface or the silicate glass. The silane(s) can be prevented from loss from the glass surface by subjecting the glass surface to a suitable heat treatment.In a particularly preferred procedure, the silane solution applied to the glass surface additionally contains a lacquer-forming binder. The silane-containing lacquer is thinly applied to the silicate glass sheet and an organo silicate glass surface is formed on subsequent drying of this lacquer.

It is also possible to apply such a silane-containing lacquer to the foil employed using one of the procedures referred to above in connection with the application of silanes dissolved only in solvents. For example, such application may be carried out continuously in an immersion bath equipped with squeezing rollers followed by drying in a continuous heating or pusher-type furnace. The manufacture of the foil can in this case also supply a fully prepared foil to the manufacture of the laminated glass.

Insofar as the use of silane-containing lacquers is contemplated, it is not even essential that all the silane may be dissolved in the lacquer solvent. A dispersion of the silane(s) in a lacquer-forming material may be employed. In such case, the silane application procedure is also applicable in accordance with the present invention to polyvinylchloride foils.

Examples of lacquer binders which can be used in the practice of this invention are non-hardening, polymethacrylates and acrylates, soluble, non-reacted polyurethanes, post-chlorinated polyvinylchloride and vinylchloride/vinyl isobutyl ether copolymer.

Lacquer binders particularly effective in achieving a good glass to foil bond are those which containn free -OH and/or -CO OH groups. Examples of such preferred lacquer binders are partially hydrolysed copolymers of vinylchloride and vinyl acetate, vinylchloride-vinyl acetate-vinyl alcohol terpolymers, vinylchloride-hydroxyalkyl acrylate copolymers, vinylchloride-vinyl acetate-unsaturated carboxylic acid (e.g.

maleic, acrylic or methacrylic acid) terpolymers and vinylchloride-unsaturated carboxylic acid alkyl ester-unsaturated carboxylic acid terpolymers. These like the lacquer binders already mentioned herein are readily available commercially.

Since reactive groups, in particular carbonyl groups, will affect the light and thermal stabilitv of the bonds produced, -OH and -CO OH group-containing lacquer binders are preferably used together with less reactive bonding agents which must, of course, be compatible therewith. Examples of the less reactive bonding agents are copolymers of vinyl chloride and vinyl acetate or unsaturated carboxylic acid alkyl esters, as well as natural or synthetic rubber.

Irrespective of whether or not a reactive lacquer binder is employed in a silanecontaining lacquer, and whether separate plasticisers are employed, stabilisers and other auxiliary materials will usually be present, the total amount of involatile components in the silica-containing lacquer is preferably from 1:0 to 20% by weight, more preferably from 2.0 to 15% by weight. The volatile components of the lacquers will be organic solvents which will be referred to hereinafter in connection with the use of silane-containing solutions in general.

Insofar as the use of ethylene and/or propylene foils is contemplated herein, it is also possible to employ ethylene and/or propylene foils which contain the silanes in a homogeneously distributed form. In this case, the silane are supplied either as such or dissolved in a solvent to the moulding compositions from which the foils are produced. When using this procedure, there is, of course, no need to provide silane surface coatings on the prepared foils or on the silicate glass sheets. For producing a homogeneous distribution of the silanes in the foil, the silanes can also be initially dissolved or finely dispersed in a plasticiser to be added to the foil-forming composition and added together with the piasticiser and possibly other conventional additives, for example stabilisers, light-protection agents and dyestuffs to the composition which is to be shaped.The mixing together of the components from which the foil is to be produced can be carried out on conventional equipment, for example, in cokneaders.

The foils employed in the process of this invention are preferably transparent, although opaque foils may be employed, depending on the purpose for which it is intended that the laminated safety glass is to be used.

The choice of silanes employed in the practice of the present invention will be as follows: a. silanes or silane mixtures which produce a strong adhesion of foil to glass, as required in the building industry and /or b. silanes or silane mixtures which produce a lesser strength of adhesion as may be used in laminated safety glass for motor vehicles.

In general, silicon organo-functional silanes tend to increase the bond strength obtained while silicon-functional silanes lower the bond strength and the silane or combination of silanes to be employed will generally be selected in accordance with the intended use of the product produced.

Silicon-functional silanes are compounds containing a functional group, for example a halogen or alkoxy group, directly linked to the silicon atom. Such groups are generally capable of being easily hydrolysed.

Silicon organo-functional silanes are essentially at least bi-functional. As well as containing at least one hydrolysable group, which is usually a halogen or alkoxy group, which is to react in the bond with the glass surface, at least one functional group is present which is bonded through one or more carbon atoms to silicon and is reactive, for example, because of the presence of amino and/or epoxy groups therein or because of the double bonds.

The silicon organo-functional silanes to be employed in the process of this invention will generally possess the general formula:

wherein R" is a hydrolysable radical, for example halogen, especially chlorine, or OR wherein R denotes an alkyl radical containing from 1 to 18 carbon atoms, the carbon atoms of which when two or more are present in the radical being possibly interrupted by hetero atoms, for example 0 or S, or an acyl radical; Riii is an alkyl radical containing from 1 to 18 carbon atoms; A is a straight-chain or branched alkylene radical containing from 1 to 10 carbon atoms, preferably from 2 to 6 carbon atoms and which may be interrupted by hetero atoms;; Z represents a radical containing a functional group, for example

wherein R1 is hydrogen or a group of formula --R""-NH, or -R"-OH wherein Rti is an alkylene radical containing from 2 to 8 carbon atoms, two radicals R1 when represent, being the same or different, and Rtv is methyl or ethyl, mis 1,2 or 3; n is 1,2 or 3; and p is 0 or 1 provided that:Z is linked to the silicon atom through at least one carbon atom forming part of A or The silicon organo-functional silanes utilised in the practice of this invention are preferably alkylene-alkoxy silanes which contain amino and/or imino groups or contain epoxy groups.When the silane contains an amino group, it is possible in this case for one or both hydrogen atoms of the amino group to be replaced by an amino- or hydroxyalkyl radical or by a polyamino radical.

One preferred class of silicon organo-functional silane for use in the process of this invention to improve the bonding force between the aforesaid plastics foils and silicate glass sheets consists of compounds of the general formula:

in which R is an alkyl radical containing from 1 to 10 carbon atoms, the carbon atoms when two or more are present in the radical being possibly interrupted by hetero atoms Riii is an alkyl radical containing from 1 to 8.

A is a straight-chain or branched alkylene radical containing from 1 to 8 carbon atoms, and which may be interrupted by hetero atoms, m is 1 or 2 or 3, n is 1 or 2 or 3, and in which Ri is a hydrogen atom, a group of formula -Rii-NH2 or-Rii-OH wherein Rii is an alkylene radical containing from 2 to 4 carbon atoms or a polyaminoalkyl radical when m is 1, and R is a hydrogen atom or a group of formula

wherein Rii, Riii, A and n have the aforesaid meanings when m is 2. Hetero atoms in R and A are preferably oxygen.

Another preferred class of silicon organo-functional silanes which may be used consists of compounds of the general formula:

wherein R. Riii, A and n have the aforesaid meanings and Riv is a hydrogen atom or a methyl or ethyl group.

Particularly preferred aminosilanes are compounds of general formula: NH2-( CH0 )-Si-( ORV)t, in which n is an integer of from 2 to 6 and RV is an alkyl radical containing from 1 to 8 carbon atoms. Alkyl radicals RV can be branched or unbranched and possibly interrupted by hetero atoms when containing more than one carbon atom, in for example the radical -CH2--CH2-O-CH3. Specific examples of these compounds are γ-aminoproply and γ-aminoethyl trialkoxy silanes. In the compounds of general formula III, the hydrogen atoms of the amino group may be replaced by an aminoalkyl or polyaminoalkyl radical (e.g. the radical [-CH,-CH2NHCH2) xCH2i -NH2 wherein x is an integer of from 1 to 8.The aminosilane of this sub-class which is most preferred for use in the practice of this invention is y-aminopropyl triethoxy silane. Other aminosilanes of this sub-class which can be used are fi-aminoethyl-y- oxypropyl methyl dialkoxy silanes and polyamino trialkoxy silanes, for example com pounds of formula [(CH2O)3Si(CH2)2]-NH-CH2(CH2NHCH2)x-CH2NH2 wherein x is an integer of from 1 to 8.

General formula I also includes within its ambit imino-silanes, preferred examples of which are compounds of general formula: HN[CH2-CH2-CH2-Si(ORv)s]2 in which Rv has the aforesaid meaning.

A particularly preferred iminosilane is bis-triethoxysilyl propylimine.

Examples of silanes of general formula II which may be employed in the practice of this invention are the e-imidazolylpropyl trialkyl silanes in which the alkyl moiety of the alkoxy group has the same meaning as the aforementioned radical RV. A particularly preferred compound of this class is y-imidazolylpropyl triethoxy silane.

Use may also be made, as above-mentioned, of silanes which contain epoxy groups. The epoxy group

may be bonded either by way of an ether groupings, (-CH2-O-) or an ester grouping,

to any alkylene silyl radical. However, it is also possible for the epoxy group to be bonded directly or by way of a cycloaliphatic ring to the alkylene radical, or for it to be a constituent of such a cycloaliphatic radical. The preparation of such silanes is described in German Patent Specification No. 1,061,321. The silanes mentioned therein and containing epoxy groups may also be employed in the practice of this invention. Silanes which contain ether bridges and which are particularly suitable are glycidyloxypropyl trimethoxy or triethoxy silanes.A preferred example of epoxysilanes which contain ester bridges is the compound

An example of an epoxy silane in which the epoxy group is a constituent of a cycloaliphatic ring is -3,4-epoxycyclohexylethyltrimethoxysilane.

Of the compounds mentioned above, the y-imidazolylpropyltriethoxysilane and the y-glycidyloxypropyltrimethoxysilane are preferred for use as silicon organo functional silanes which increase the bond strength.

As will be appreciated from the foregoing, it is also possible to employ silicon organo-functional silanes with olefinically unsaturated bonds, for example silanes which contain vinyl, propenyl, acryl or methacrylic groups. These silanes can only be used to produce an increase in the bonding power when they are used together with radical formers. Not only is the bonding power not increased without addition of radical formers, but it may undergo a slight reduction.

Examples of radical formers which may be employed include the compounds usually employed in the radical polymerisation of olefinically unsaturated compounds, especially peroxides, for example dicumyl peroxide. The radical formers are generally employed in quantities of from 0.01 to 1% by weight, preferably from 0.01 to 0.5% by weight, calculated on the solvent or lacquer composition employed. Examples of these silanes are vinyl trialkoxy silanes, for example vinyl trimethoxy silane, vinyl triethoxy silane, ,-methacryloxypropyl trialkoxy silanes, for example the trimethoxy or triethoxy silanes, vinyl-tris--methoxyethoxy silane or vinyl triacetoxy silane.

In laminated safety glass produced according to this invention and wherein very good adhesion is required between silicate glass and foil, only silicon organo-functional silanes will generally be used. Such laminated safety glasses can be used, inter alia in the building industry, for example, as window panes, armoured glass or in partitions. Laminated safety glass with a quality of bonding lying in a middle region of the adhesion scale according to the pummel test are used in the vehicle industry, for example as glazing material in motor vehicles, rail vehicles, agricultural vehicles, ships and aircraft. In these fields of application, the bonding power required for the specific purpose of use can be adjusted by varying the type and quantity of silane used. Obviously, it is necessary to take into account, in addition, the bonding power of the plastics foil in the absence of any silane at all. By the use of one or more silanes in varying proportions it is possible to obtain the bonding strength which is required.

If the bonding power of a foil treated with a silicon organo-functional silane is too high for a particular purpose of use then it is impossible to employ a silane or silane mixture which reduces the bonding power as the only silane component; a silane-functional silane as herein defined will generally be employed in such a case either alone or as a significant component of a mixture thereof with a silicon organo functional silane.

The bonding power of a glass sheet to a soft foil used as an adhesive foil and formed of one of the aforesaid plastics materials is determined by the so-called "pummel" test. In this test, a test element, with a size of about 150 X 300 mm is chilled for about 2 to 8 hours at say --18"CC-0.5"C, laid on a metal block sloping at about 45" and hammered with a flat-headed hammer until the silicate glass dis integrates. The test surface has a size of about 100 X 150 mm.The adhesion of the foil to the glass is visually evaluated in accordance with a scale of from 0 to 10 whose values represent: % free film surface pummel value 100 0 95 1 90 2 85 3 60 4 40 5 20 6 10 7 5 8 2 9 0 10 The visual evaluation is facilitated by the fact that the indicated pummel values are also suitable for setting out to scale on diagrams. It has been found that this pummel test, which is not quantitative, is fully adequate for practical purposes, and that the adhesion can be judged sufficiently accurately by visual evaluation.

Silicon-functional silanes for use in the process of this invention include com pounds of the general formula - - Si n RVi4n in which R represents a straight-chain or branched alkyl radical containing from 1 to 18 carbon atoms, preferably from 1 to 10 carbon atoms, RVi represents a halogen atom, preferably a chlorine atom, or an alkoxy group containing from 1 to 8 carbon atoms which, containing a plurality of carbon atoms, may be interrupted by one or more hetero atoms, such as oxygen or sulphur, or an acyl radical, which is bonded through an oxygen atom to the silicon atom, and in which n is 1, 2 or 3, preferably 1.When a plurality of groups R and/or RVi is/are present, they may be the same or different The following are examples of silicon functional silanes of the aforesaid general formula: propyltriethoxysilane, propyl trimethoxysilane, isopropyl dimethoxyethoxy silane and n-butyl or isobutyl-triethoxy or trimethoxy silane, or isobutyl triacetoxy silane.

Solvents with which the silanes are utilised will be those within which the silanes exhibit good solubility, when silane solutions are to be employed. The solvents should undergo ready vaporisation after the foils have been treated. In addition, the solvents should have good wetting power for the plastics foils without causing their dissolution. Such properties are possessed, for example, by aromatic hydrocarbons, for example toluenes or xylene, like petroleum ethers, as well as alkyl esters of aliphatic carboxylic acids, for example ethyl acetate or butyl acetate. It is also possible to employ alcohols, for example isopropanol or ketone, for example methylisobutyl ketone. A combination of solvents may also be employed.

The amount of silane employed will generally depend upon the bonding effect required. Insofar as solutions are to be employed, it will also depend upon the solubility of the silane in the solvent. In general, when silane solutions are employed, total silane concentrations of from 0.0001 to 10% by weight, preferably from 0.0005 to 7% by weight, based on the solvent may be employed. When partially acetalised polyvinylalcohol foils are being employed, the concentration of silane in solution will generally be from 0.0001 to 7.0% by weight, preferably from 0.0005 to 5.0% by weight based on the solvent. Particularly when employing ethylene and/or propylene foils, the total silane concentration in solutions thereof is preferably from 0.01 to 10% by weight, more preferably from 0.05 to 7% by weight of the solvent.

Irrespective of whether they are dissolved in an organic solvent or dissolved or dispersed in a lacquer, when the foil is an ethylene and/or propylene foil, the silicon organo-functional silane is preferably employed in an amount of from 0.0001 to 7%, more preferably from 0.0005 to 5%, based on the weight of solvent present. Such values~are also applicable to the case where a polyvinyl chloride film is employed and a suspension of organo-functional silane in a lacquer is used. When partially acetalised polyvinylalcohol foils are employed, it is sufficient for a silicon organofunctional silane to be applied in an amount of from 0.0001 to 2%, preferably from 0.0005 to 1% by weight based on the weight of solvent present.In general, the silicon-functional silanes may be employed in amounts of from 1 to 10, preferably from 2 to 7% by weight of the solvent present.

When using lacquers whose binders contain free hydroxyl and/or carboxyl groups, the amount of silane employed will generally be less than otherwise as indicated herein. In such cases, when using silicon organo-functional silanes containing epoxide groups, it is sufficient for the silanes to be employed in the lacquer in amounts of from 0.001 to 5% by weight, preferably from 0.001 to 2% by weight based on the solvent. When silicon organo-functional silanes containing amino groups are employed, the silanes are preferably employed in the lacquer in amounts of from 0.0001 to 2% by weight, more preferably from 0.0005 to 1% by weight, based on the solvent.

When silanes are added directly to an ethylene and/or propylene foil-forming composition prior to the thermoplastic deforming thereof into a foil, the silane quantity employed is preferably from 0.1 to 5.0% by weight, more preferably from 0.5 to 3% by weight of the other components of the foil-forming composition. When external plasticisation of foils is carried out, the total amount of plasticiser employed preferably amounts to from 10 to 65 parts by weight, calculated on 100 parts by weight of the foil-forming polymer.

In addition to the various binders indicated hereinabove, it is pointed out that when using partially acetalised polyvinyl alcohol foils, a particularly suitable binder for use in a lacquer is a partially acetalised polyvinylalcohol which preferably corresponds in its compoosition to that of the foil itself which is being employed. In principle, however, when using partially acetalised polyvinylalcohol foils, it is also possible to employ other of the aforementioned film-forming binders, especially those which contain free hydroxyl and/or carboxyl groups.

In laminated glasses produced by the process of this invention and comprising at least one film layer formed of a plastics material as aforesaid, the silicate glass used can be un!ardened or hardened, flat or curved, vapour-coated, printed, dyed, etched or structurised. The glass can be provided with a wire insert. In addition, it is possible to use colourless, coloured but transparent or coloured and translucent, foils which contain the particular polymer and which may be printed. The foil may contain inlaid wires, wire meshes, woven fabrics or objects, for example solar cells.

The thicknesses of the silicate glasses and of the foils formed from the various polymers and modified or treated in accordance with the invention can be selected as required. Likewise, the number of the separate layers of the laminated article can be selected as required. As a result, laminated glass can be produced for use in the building industry in doors and door installations, balconies or facades, in partition walls for use as room dividers, balcony dividers or enclosures of premises, in roofs or roof sections of terraces, light-transmissive canopies or greenhouses, in compartments for telephone or computer installations, showcases, cash offices, prisons or rooms where there is danger of explosion or implosion, as well as a safety glass for protection against burglary, larceny, firing of firearms, fire, sound, cold, warmth, heat.It may be necessary in some of these cases for alarm or heating wires to be inncorporated.

Laminated glass may be produced by the process of this invention for use in the glazing of motor vehicles, rail vehicles, ships and aircraft, particularly as windshielding, stern or side windows, doors and partitions. In certain cases, the foils containing the various polymers and modified or treated in accordance with the invention may be used to produce a multiple lamination in combination with other transparent synthetic plastics materials. Accordingly, other types of laminated structures become conceivable. Such structures may contain, as well as silicate glass and foil, polymethyl methacrylate, polycarbonate, polyethylene terephthalate, hard polyvinylchloride, polyamide layers which are tough elastic materials or plasticised polyvinyl butyral, polyurethane, copolymers of ethylene, polyamides, polyepoxides, polysiloxanes and polymethacrylates as soft elastic adhering materials.

The following Examples, in which all parts and percentages are expressed on a weight basis, unless otherwise indicated illustrate this invention. For succinctness many of the silanes mentioned in the Examples are identified frequently by abbreviations of their names identified in the Examples.

Examples 1 to 14.

Foils having a thickness of 0.4 mm were produced from various copolymers of ethylene and vinyl acetate and treated with silane solutions by dipping or immersion therein.

Toluene was chosen as solvent for the silane since this could be readily vapourised before the further processing of the treated foils. The foils were thereafter placed between two glass sheets, the assembly was passed through a pair of rubber rollers at ambient temperature to remove air therebetween and then heated in an autoclave at 12 bara and 170 C for 1 hours, so that a deffect-free laminated glass was formed.

The adhesion of the foils to the galss was determined by the pummel method carried out at - 20 C, +23 C and +90 C.

TABLE 1

Vinyl acetate Pummel value at content of Silane % by Dicumyl Example No. foil weight peroxide -200C +230C +90 C 1 8% by wt. ') none none 0 1 3 2 " IMEO ,, 10 10 10 3 ,, 1% GLYMO " 4 10 10 4 " 1%VTEO " 0 0 0 5 " 1%VTEO 0.1% by wt. 1 10 10 6 ,, 1% VIMO ,, 0 10 10 7 " 1% MEMO " 3 6 10 8 26% by wt. 2) none none 0 2 5 9 " 1%IMEO ,, 10 10 10 10 " 1% GLYMO ,, 10 10 10 11 " 1%VTEO ,, 0 0 0 12 ,, 1% VTEO 0.1% by wt. 10 10 10 13 " 1% VTMO ,, 10 10 10 14 ,, 1% MEMO ,, 10 10 10 IMEO = yimidazolylpropyl triethoxy silane GLYMO = y-glycidyloxypropyl trimethoxy silane VTEO = vinyl triethoxy silane VTMO = vinyl trimethoxy silane MEMO = y-methacryloxypropyl trimethoxy silane ) Shore-A hardness = 97 2) Shore-A hardness = 79 Examples 15 to 22.

The procedure of Examples 1 to 14 was repeated, but with the difference that the autoclave process was carried out at 12 bars and at 140 C for 3 hours. The following results were obtained in the pummel test.

TABLE 2

Vinyl acetate Pummel value at content of Silane % by Dicumyl Example No. foil weight peroxide -20 C +23 C +90 C 15 26% by wt. 1) none none 0 2 5 16 " 1% IMEO " 10 10 10 17 " 1%GLYMO 10 10 10 18 ,. 1% VTEO 0.1% by wt. 3 10 10 19 45 10 by wt. 2) none none 0 5 10 20 " 1% IMEO 10 10 10 21 " 1% GLYMO ,. 10 10 10 22 " 1% VTEO 0.1% by wt. 0 5 10 IMEO = y-imidazolylpropyl triethoxy silane GLYMO= y-glycidy loxypropyl trimethoxy silane VTEO = vinyl triethoxy silane t) Shore-A hardness = 79 2) Shore-A hardness = 85 Examples 23 to 27.

The procedure of Examples 1 to 14 was again repeated but using the following foils: 1) Foils of a copolymer of ethylene and butylacrylate having Shore-A hardness of 87 (obtainable commercially under the name Lupolen A 2710 HX-Lupolen is a Registered Trade Mark of BASF).

2) Foils of a quaternary polymer of ethylene, an additional olefine, acrylic acid and acrylates (obtainable commercially under the name Lupolen A 2910 MX and having a Shore-A hardness of 94).

The pummel values of the products obtained were as follows: TABLE 3

Pummel value at Example Silane % No. Copolymer by wt. -200C +23 OC +900C 23 A 2710 HX none 0 1 7 24 ,. 1% IMEO 10 10 10 25 A 2910 MX none 10 10 10 26 ,. 1% ATAO 10 10 10 27 5% ATAO 1 5 5 IMEO = y-imidazolylpropyl triethoxy silane ATAO = isobutyl trimethoxy silane Examples 28 and 29.

The basic working conditions of Examples 15 to 17 were utilised in further repetitions of the process of Examples 1 to 14, but with the further difference that the silanes were not used in pure solvent, but in lacquers.

One lacquer (Lacquer 1) contained, as binder, a partially hydrolysed copolymer of vinyl chloride and vinyl acetate containing vinyl alcohol groups (obtainable commercially under the name Vinylite VAGH-Vinylite is a Registered Trade Mark of Union Carbide Corporation), 25% by weight of diisodecyl phthalate as plasticiser, based on the weight of the copolymer, a stabiliser system for the copolymer and methyl isobutyl ketone as solvent. The lacquer contained 10% by weight of binder composition, that is copolymer + plasticiser + stabiliser, and 1% by weight of y-imidazolylpropyl triethoxy silane (IMEO).

A second lacquer (lacquer 2) was prepared, using the aforementioned plasticised and stabiliser Winylite VAGH copolymer and another copolymer, being a terpolymer of vinyl chloride, vinyl acetate and maleic acid (obtainable commercially under the name Hostaflex M 133-Hostaflex is a Registered Trade Mark of Hoechst AG).

This latter polymer was plasticised and stabilised in the same manner, the relative proportions by weight of the two copolymers VAGH and M 133 being 24:1, while the proportion of binder composition (copolymers + plasticiser + stabíliser) amounted to 15% by weight. The lacquer also contained 1% by weight of ,- glycidyloxypropyl trimethoxy silane (GLYMO).

Foils having a thickness of 0.4 mm and obtained from a copolymer of ethylene with 26% by weight of vinyl acetate were treated with these lacquers by dipping.

After the evaporation of the solvent, the treated foils were laid between two glass sheets. To extract the air entrapped in the assemblies, the assemblies were passed through a pair of rubber rollers and further processed in an autoclave at 12 bars and 1400C over a period of 3 hours to provide defect-free laminated glasses. The foil adhesion was established by the pummel method and gave the following values: TABLE 4

Pummel values at Example Lacquer No. No. -20 C +23 C +90 C 28 1 10 10 10 29 2 10 10 10 Example 30.

Fcils having a thickness cf 0.4 mm were produced from a copolymer of ethylene and 26% by weight of vinyl acetate and utilised in the production of laminated glass by the procedure of Example 16 using a 1% by weight solution of y-imid- azolylpropyl triethoxy silane (IMEO) in toluene.

In addition, plasticised polyvinyl butyral (PVB) foils with a thickness of 0.4 mm and showing good adhesion to glass (bullding glass quality) were alr-conditioned to a moisture content of 0.45% by weight and likewise processed to form a laminated glass.

Both types of laminated glass were thereafter subjected to a ball-dropping test in accordance with DIN 52 306, carried out at temperatures of +23 C and -200C, using a steel ball weighing 227 g. The results obtained are set out in Table 5. As may be seen from Table 5, when using the external plasticiser-free foils of a copolymer of ethylene and 26% by weight vinyl acetate, laminated safety glasses were produced which, as compared with those consisting of plasticised polyvinyl butyral, were particularly resistant in the cold to the effect of impact. The safe dropping height of the ball was about twice as high at a temperature of --20"C.

TABLE 5

Copolymer Foil PVB Foil Dropping 0.4 mm foil weight of 0.4 mm foil weight of Temperature height (m) fissure (cm) penetration splinters (g) fissure (cm) penetration splinters (g) 23 C 6 none none 0.2 - - " 7 2 none 3.3 - - " 8 5 none 2.2 - - " 8 2/1 none 1.2 - - " 8 7 none 7.9 none none 1.3 " 9 10 yes - - - " 12 - - - 9/2 " 6.8 " 13 - - - 12/4 " 6.2 " 14 - - - 11 yes " 16 - - - 12/6/2 none 7.5 -20 C 5 - - - none none 0 " 6 none none 0.1 none none 0.2 " 7 none none 0.3 - yes " 8 3 none 1.8 - - " 10 3/1 none 2.0 - - " 11 12/12/12 none 4.4 - - " 12 12/5 yes - - - Examples 31 to 39.

Plasticised polyvinyl butyral foil having a high glass adhesion (quality for building glass, pummel value (10) was coated with solutions consisting of toluene as solvent and various silanes in various concentrations by dipping or immersion. The solvent was thereafter removed by evaporation at room temperature. The variously treated foils were air-conditioned to a water content of 1.45%, placed between two glass plates and heated to such an extent that a temperature of 90 C could be measured on the glass surfaces.The warm sandwich obtained was passed through a pair of rubber rollers for air extraction. a preliminary bond was formed which was improved by treatment in an autoclave at 12 bars, 140 C, for 3 hours, as a result of which a flawless laminated glass was formed. the glass adhesion of the foils was determined at --20"C, using the pummel method which gave the following results: TABLE 6

Example No. Silane % by weight Pummel value at -20 C 31 0 ATAO 10 31 0.5 " 10 33 1 " 10 34 2 " 7 35 3 " 5 36 5 " 3 37 5.5 , 1 38 6 , 1 39 7 " 1 40 0.1 MEMO 4 41 1 " 0 42 5 , 0 43 0.1 O.1S-IFO 1 44 5 , 0 45 0.1 GLFMO 3 46 1 , 0 47 0.1 ACTMO 3 48 1 " 1 49 5 , 0 ATAO = isobutyl trimethoxy silane MEMO = y-methacryloxypropyl trimethoxy silane SIFO = 2-[triethoxysilyl]-ethyl phosphonic acid diethyl ester GLFMO = 4[methyl-3 'trimethoxysilyl)-propoxyl-1,3-dioxolan ACTMO - [1-polyethylene/propyleneglycol)-3-trimethoxysilyi) propyl]-acetate Examples 50 to 57.

A plasticised polyvinyl butyral foil having high glass adhesion (building glass quality, pummel value 10) was treated with solutions of 3.0% by weight or 5.5% by weight respectively of isobutyl trimethoxy silane (ATAO) in toluene; after evaporation of the solvent to different water contents, the silanised foil was airconditioned.

The manufacture of the laminated glass was carried out by the procedures of Examples 31 to 49. For comparison purposes, laminated glass was prepared with an untreated polyvinyl butyral foil of the same quality and of the same water content.

The results obtained are apparent from the following Table.

TABLE 7

Pummel value at -200C ATAO % Water content Example No. by wt. % by wt. Untreated foil Treated foil 50 5.5 0.31 10 1 51 5.5 0.41 10 1 52 5.5 0.64 7 1 53 5.5 0.82 4 1 54 3.0 0.32 10 5 55 3.0 0.41 10 5 56 3.0 0.61 V 2 57 3.0 0.82 4 1 Examples 58 to 60.

The procedure of Examples 31 to 49 was repeated, with the difference that petroleum ether and xylene were used in addition to toluene for the preparation of a 5% by weight solution of isobutyl trimethoxy silane utilised as silane solution.

The following results were obtained in the pummel test.

TABLE 8

Pummel value-s at -200C Example No. Solvent untreated foil I treated foil 58 toluene 10 3 59 petroleum 10 4 ether 60 xylene 10 4 Examples 61 to 79.

A plasticised polyvinyl butyral foil with controlled glass adhesion (quaiity for windscreens, pummel value 2) was used in a repetition of the procedure of Examples 31 to 49. The foil was treated as described in Examples 1 to 30 and processed to form laminated glass having the following pummel behaviour: TABLE 9

Example No. Silane % by weight Pummel value at -200C 61 0 IMEO 2 -62 0.0005 ., 2 63 0.001 " 3 64 0.002 ,, 3 65 0.004 " 6 66 0.006 " 6 67 0.008 ,, 7 68 0.01 " 10 69 0.02 ,, 10 70 0.03 " 10 71 0.04 ., 10 72 0.001 AMEO 2 73 0.005 ., 6 74 0.01 ., 6 75 0.05 " 10 76 0.006 GLYMO 3 77 0.03 " 4 78 0.09 " 5 79 0.06 . 5 IMEO = y-imidazolylpropyl triethoxy silane AMEO = y-aminopropyl triethoxy silane GLYMO = y-gylcidyloxypropyl trime thoxy silane Examples 80 to 83.

A plasticised polyvinyl butyral foil of the type used in Examples 61 to 79 having controlled glass adhesion was treated with a solution of 0.01% by weight of y-imidazolylpropyl triethoxy silane (IMEO) in tcluene and, after the evaporation of the solvent, was air-conditioned to different water contents. The manufacture of the laminated glass was carried out as described in Examples 1 to 30 to yield products having the following pummel values: TABLE 10

Pummel value at -20 C Water content Example No. % by weight untreated foil treated foil 81 0.41 3 10 82 0.64 3 10 84 0.82 2 10 Examples 84 to 89.

Plasticised polyvinyl butyral foil having high glass adhesion (quality for building glass, pummel value 10) was used in the manufacture of laminated safety glass. The glass sheets used had a vaporised metal coating, the vapour-coated sides of the glass being disposed facing the polyvinyl butyral foil, i.e. on the inside. The polyvinyl butyral foils were treated before hand with a solution of silane in toluene and were air-conditioned tb a water-content of 0.45%. The products obtained showed the following pummel behaviour: TABLE 11

Pummel values at -200C Silane Example No. Glass Coating % by weight ~ untreated foil treated foil 84 Auresin 50/36* 5 AMEO 1 7 85 Auresin 55/42* 5 AMEO 1 5 86 Metallic 50/47 5 AMEO 1 2 87 Auresin 50/36* 5 GLYMO 1 3 88 Auresin 55/42* 5 GLYMO 1 4 89 Metallic 50/47 5 GLYMO 1 1 3 AMEO = raminopropyl triethoxy silane GLYMO = y-glycidyloxypropyl trimethoxy silane * Auresin is a Registered Trade Mark.

Examples 90 to 97.

Plasticised polyvinyl butyral foil with high glass adhesion and glass surface-coated in the manner described in Examples 74 to 79 were used for the manufacture of laminated safety glass. However, in place of a silane solution, a silane-containing lacquer was employed. For this purpose, a solution of 2% by weight of plasticised polyvinyl butyral foil as lacquer binder and 1% by weight of silane was prepared.

The solvent used was a 1:4 by volume mixture of dioxane and methyl isobutyl ketone. The polyvinyl butyral foil to be laminated (Examples 90 to 93) or the coated glass (Examples 94 to 97) were treated with this silane-containing lacquer.

Before preparing the bond, the polyvinyl butyral foil to be laminated was airconditioned to a water content of 0.45%. The products obtained showed the following pummel behaviour.

TABLE 12

Pummel values at -200C Example No. Glass Coating Silane untreated foil treated foil 90 Calorex* IMEO 6 10 91 Parelio IMEO 6 10 92 Calorex* GLYMO 6 10 93 Parelio GLYMO 6 10 untreated glass treated glass 94 Calorex* IMEO 6 10 95 Parelio IMEO 6 10 96 Calorex* GLYMO 6 10 97 Parelio GLYMO 6 10 IMEO = y-imidazolylpropyl triethoxy silane GLYMO= y-glycidyloxypropyl trimethoxy silane * Registered Trade Mark.

WHAT WE CLAIM IS:-' 1. A process for the manufacture of laminated safety glass comprising bonding one or more silicate glass sheets at an elevated temperature of up to 2000C and under a superatmospheric pressure to a polyvinylchloride, as hereinbefore defined, foil, an ethylene and/or propylene foil, as hereinbefore defined, or a partially acetalised polyvinylalcohol foil, bonding being assisted by means of a silicon organo-functional silane as hereinbefore defined and/or a silicon functional silane as hereinbefore defined, with the provisos that when a said polyvinylchloride foil is employed, the silicon organo-functional silane and/or silicon functional silane is applied to the surface of a said foil and/or to a said glass sheet dispersed in a lacquer and that when a partially acetalised polyvinylalcohol foil is used, the silicon organo-functional silane and/or silicon functional silane is applied to the surface of said foil and/or to a said glass sheet dissolved in a solvent and/or dispersed in a lacquer, a solvent when used, being removed after the application to the foil and/or glass sheet surface. 2. A process as claimed in claim 1, wherein bonding is assisted by means of a said silicon organo-functional silane.

3. A process as claimed in claim 1 or 2, wherein a said ethylene and/or propylene foil is employed.

4. A process as claimed in claim 3, wherein the foil has a Shore-A hardness measured in accordance with DIN 53505 of from 40 to 98.

5. A process as claimed in claim 4, wherein the foil has a Shore-A hardness measured in accordance with DIN 53505 of from 50 to 95.

6. A process as claimed in any one of claims 3 to 5, wherein the ethylene and/or propylene foil is intemally plasticised.

7. A process as claimed in claim 6, wherein said foil is formed of an ethylene or propylene copolymer which includes vinyl acetate as a comonomer.

8. A process as claimed in any one of claims 3 to 7, wherein said foil is formed of an ethylene and/or propylene copolymer which includes as a copolymer butadiene, an alkyl vinyl ester, vinylchloride, vinyl fluoride, acrylic acid, an acrylic acid ester, maleic anhydride, a maleic acid ester or styrene.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. TABLE 12 Pummel values at -200C Example No. Glass Coating Silane untreated foil treated foil 90 Calorex* IMEO 6 10 91 Parelio IMEO 6 10 92 Calorex* GLYMO 6 10 93 Parelio GLYMO 6 10 untreated glass treated glass 94 Calorex* IMEO 6 10 95 Parelio IMEO 6 10 96 Calorex* GLYMO 6 10 97 Parelio GLYMO 6 10 IMEO = y-imidazolylpropyl triethoxy silane GLYMO= y-glycidyloxypropyl trimethoxy silane * Registered Trade Mark. WHAT WE CLAIM IS:-'

1. A process for the manufacture of laminated safety glass comprising bonding one or more silicate glass sheets at an elevated temperature of up to 2000C and under a superatmospheric pressure to a polyvinylchloride, as hereinbefore defined, foil, an ethylene and/or propylene foil, as hereinbefore defined, or a partially acetalised polyvinylalcohol foil, bonding being assisted by means of a silicon organo-functional silane as hereinbefore defined and/or a silicon functional silane as hereinbefore defined, with the provisos that when a said polyvinylchloride foil is employed, the silicon organo-functional silane and/or silicon functional silane is applied to the surface of a said foil and/or to a said glass sheet dispersed in a lacquer and that when a partially acetalised polyvinylalcohol foil is used, the silicon organo-functional silane and/or silicon functional silane is applied to the surface of said foil and/or to a said glass sheet dissolved in a solvent and/or dispersed in a lacquer, a solvent when used, being removed after the application to the foil and/or glass sheet surface.

2. A process as claimed in claim 1, wherein bonding is assisted by means of a said silicon organo-functional silane.

9. A process as claimed in any one of claims 3 to 8, wherein the silane(s)

is/are incorporated in a moulding composition from which said foil is produced.

10. A process as claimed in any one of claims 3 to 8, wherein the silane(s) is/are applied to the surface of said foil and/or a said glass sheet in the form of a solution thereof in an organic solvent which is then removed.

11. A process as claimed in any one of claims 3 to 8, wherein the silane(s) is/are applied to the surface of a said foil and/or a said glass sheet in the form of a dispersion thereof in a lacquer whose organic solvent is then removed.

12. A process as claimed in claim 1 or 2, wherein a said partially acetalised polyvinylalcohol foil is used, the silicon organo-functional silane and/or silicon functional silane being applied to a surface of said foil and/or to a said glass sheet dissolved in a solvent, the solvent being removed after the application to the foil and/or glass sheet surface.

13. A process as claimed in claim 1 or 2, wherein a said partially acetalised polyvinylalcohol foil is used, the silicon organo-functional silane and/or silicon functional silane being applied to a surface of a said foil and/or to a said glass sheet dispersed in a lacquer whose solvent is then removed.

14. A process as claimed in claim 12 or 13, wherein a polyvinylbutyryl foil is used as the partially acetalised polyvinylalcohol foil.

15. A process as claimed in claim 10 or 12, wherein the silicon organo-functional silane and/or silicon functional silane is/are dissolved in a solvent which additionally contains a lacquer binder.

16. A process as claimed in claim 1 or 2, wherein a polyvinylchloride foil is used, the silicon organo-functional silane and/or silicon functional silane being applied to the surface of said foil ad/or to a said glass sheet dispersed in a lacquer whose solvent is then removed.

17. A process as claimed in claim 16, wherein the polyvinylchloride has a K-value of from 50 to 80.

18. A process as claimed in claim 17, wherein the polyvinylchloride has a K-value of from 60 to 75.

19. A process as claimed in any one of claims 16 to 19, wherein the polyvinylchloride is a homopolymer of vinylchloride.

20. A process as claimed in any one of claims 16 to 18, wherein the polyvinylchloride is a copolymer of vinyl chloride with. one or more monomers chosen from hydrocarbon monomers, halogenated hydrocarbons, alcohols, ethers, acids and hetero compounds which contain in their molecules sites of ethylenic unsaturation.

21. A process as claimed in claim 20, wherein the polyvinylchloride iç a terpolymer of vinylchloride, ethylene and vinyl acetate.

22. A process as claimed in any one of claims 16 to 18, wherein the polyvinyl chloride is a graft polymer of vinylchloride or a copolymer of ethylene and vinyl acetate.

23. A process as claimed in any one of claims 16 to 22, wherein the polyvinylchloride is a chlorination product of homopolymerised vinylchloride, a copolymer of vinylchloride and an ethylenically unsaturated monomer or a graft polymer of vinyl chloride.

24. A process as claimed in any one of claims 16 to 23, wherein the polyvinylchloride is present in the foil in admixture with a polymer not derived from vinylchloride and constituting not more than 50% by weight of the polymer blend thereby produced.

25. A process as claimed in claim 24, wherein the polymer is polyvinyl acetate, a copolymer of vinyl acetate and ethylene or acrylonitrile- or methacrylonitrilebutadiene styrene.

26. A process as claimed in any one of claims 16 to 25, wherein the foil is plasticised with a phthalate, aliphatic dicarboxylic acid ester, phosphoric acid ester or polyester plasticiser.

27. A process as claimed in any one of claims 16 to 26, wherein the foil has a Shore-A hardness measured in accordance with DIN 53505 of from 40 to 98.

28. A process as claimed in claim 27, wherein said Shore hardness is from 50 to 95.

29. A process as claimed in any one of claims 11 and 13 to 28, wherein a lacquer containing the silicon organo-functional silane and/or silicon functional silane is applied to the foil and/or glass sheet, the lacquer containing a lacquer binder which is a non-hardening polymethacrylate or polyacrylate, a polyurethane, post-chlorinated polyvinyl chloride, or a copolymer of vinylchloride and vinyl isobutylether.

30. A process as claimed in any one of claims 11 and 13 to 28, wherein a lacquer containing the silicon organo-functional silane and/or silicon functional silane is applied to the foil and/or glass sheet, the lacquer containing a lacquer binder which contains reactive OH- and/or -CO OH groups.

31. A process as claimed in claim 30, wherein the lacquer binder is a vinylchloride-vinyl acetate-vinyl alcohol terpolymer.

32. A process as claimed in claim 30, wherein the lacquer binder is a partially hydrolysed copolymer of vinyl chloride and vinyl acetate, a vinyl chloride-hydroxyalkyl acrylate copolymer, a vinylchloride-vinyl acetate-unsaturated carboxylic acid terpolymer or a vinyl chloride-unsaturated carboxylic acid alkyl ester-unsaturated carboxylic acid terpolymer.

33. A process as claimed in claim 32, wherein the lacquer binder is a vinylchloride-vinyl acetate-maleic acid terpolymer.

34. A process as claimed in any one of claims 30 to 33, when not appended to claim 2, wherein bonding is assisted by means of a said organo-functional silane.

35. A process as claimed in any one of claims 1 and 2 to 33, when not appended to claim 2, wherein bonding is assisted by means of a combination of a said silicon organo-functional silane and a said silicon functional silane.

36. A process as claimed in any one of claims 1 to 33 and 35, wherein the silicon organofunctional silane possesses the general formula:

wherein R" is a hydrolysable radical, Rii' is an alkyl radical containing from 1 to 18 carbon atoms; A is a straight chain or branched alkylene radical containing from 1 to 10 carbon atoms and which may be interrupted by hetero atoms; Z represents a radical containing a functional group; n is 1, 2 or 3 and p is 0 or 1, provided that Z is linked to the silicon atom through at least one carbon atom forming part of A or Z.

37. A process as claimed in claim 36, wherein R" is a halogen atom or a radical of formula OR wherein R denotes an acyl radical or an alkyl radical containing from 1 to 18 carbon atoms, the carbon atoms of which when two or more are present in the radical being possibly interrupted by hetero atoms.

38. A process as claimed in claim 36 or 37, wherein Z denotes a halogen atom, an olefinically unsaturated group, or a group of formula

wherein R is hydrogen or a group of formula - R - NH2 or --R" -- OH wherein R" is an alkylene radical containing from 2 to 8 carbon atoms, two radicals Ri, when present, being the same or different, and Riv is methyl or ethyl, and m is 1, 2 or 3.

39. A process as claimed in claim 38, wherein Z denotes an olefinically unsaturated group and the silicon organofunctional silane is used in conjunction with a free radical former.

40. A process as claimed in claim 39, wherein the free radical former is used in an amount of from 0.01 to 1% by weight of the silane containing solution or lacquer.

41. A process as claimed in claim 39 or 40, wherein the silicon organofunctional silane is a vinyl trialkoxy silane, a y-methacryloxy propyl trialkoxy silane, vinyl-tris ,B-methoxyethoxy silane or vinyl triacetoxy silane.

42. A process as claimed in any one of claims 1 to 33 and 35, wherein the silicon organofunctional silane contains at least one amino and/or imino group or at least one epoxy group.

43. A process as claimed in claim 41, wherein one or both of the hydrogen atoms of the amino group is/are replaced by an amino- or hydroxyalkyl radical or by a polyamino radical.

44. A process as claimed in claim 41, wherein the silicon organofunctional silane possesses the general formula:

in which R is an alkyl radical containing from 1 to 10 carbon atoms, the carbon atoms, when two or more are present being optionally interrupted by one or more hetero atoms, Riii is an alkyl radical conhtaining from 1 to 8 carbon atoms, A is a straight-chain or branched alkylene radical containing from 1 to 8 carbon atoms and which may be interrupted by one or more hetero atoms, m is 1, 2 or 3, n is 1, 2 or 3 and in which:: R1 is a hydrogen atom or a group of formula -R1-OH or Ri'KH2 wherein R" is an alkylene radical containing from 2 to 4 carbon atoms when m is 1, and R1 is a hydrogen atom or a group of formula

wherein Rti, With, A and n have the aforesaid meanings when m is 2.

45. A process as claimed in claim 41, wherein the silicon organofunctional silane possesses the general formula: NH2-(CH2)n-Si-(ORv)3 in which n is an integer of from 2 to 6 and Rv is a branched or unbranched alkyl radical containing from 1 to 8 carbons which, when more than one carbon atom is present, may be interrupted by one or more hetero atoms.

46. A process as claimed in claim 42 or 43, wherein the hetero atom(s) is/are oxygen.

47. A process as claimed in claim 44, wherein the silicon organofunctional silane is a y-aminopropyl or fi-aminoethyl trialkoxy silane.

4.8 A process as claimed in claim 44 or 45, wherein the amino group of the silicon organofunctional silane is substituted by an aminoalkyl or polyaminoalkyl radical.

49. A process as claimed in claim 48, wherein the polyaminoalkyl group possesses the general formula [-CH2 (CH2NHCH2 ) xCH2-j -NH, wherein x is an integer of from 1 to 8.

50. A process as claimed in claim 41, wherein the silicon organofunctional silane is y-aminopropyl triethoxy silane or a ss-aminoethyl-y-oxypropyl methyl dialkoxysilane.

51. A process as claimed in claim 43, wherein the silicon organofunctoinal silane is a compound of general formula: HN[CH2-CH2-CH2-Si(ORv)3]2 wherein RV is a branched or unbranched alkyl radical containing from 1 to 8 carbons which, when more than one carbon atom is present, may be interrupted by one or more hetero atoms.

52. A process as claimed in claim 51, wherein the hetero atoms is/are oxygen.

53. A process as claimed in claim 51, wherein said compound is bis-triethoxy silylpropylimine.

54. A process as claimed in claim 44, wherein the silicon organofunctional silane is a compound of general formula:

wherein R, R"', A and n have the meanings set out in claim 10 and R'v is a hydrogen atom or a methyl or ethyl group.

55. A process as claimed in claim 54, wherein said compound is a 7-imidazolyl- propyl trialkoxy silane.

56. A process as claimed in claim 55, wherein said compound is y-imidazolyl- propyl triethoxy silane.

57. A process as claimed in claim 41, wherein the silicon organofunctional silane contains an epoxy group bonded by way of an ether grouping, an ester grouping or a cycloaliphatic ring to an alkylene silyl radical.

58. A process as claimed in claim 41, wherein the silicon organofunctional silane contains a cycloaliphatic radical subtituted by an alkylene silyl radical and having an epoxy group fused thereto.

59. A process as claimed in claim 57, wherein the silicon organofunctional silane is glycidyloxypropyl trimethoxysilane, glycidyloxypropyl triethoxysilane or a compound of formula

60. A process as claimed in claim 58, wherein the silicon organofunctional silane is ,ss-3,4-epoycyclohexylethyltrimethoxysilane.

61. A process as claimed in any one of claims 41 and 56 to 60, when appended directly or indirectly to claim 30, wherein the silicon organofunctional si]ane contains epoxy groups and is present in said solution in an amount of from 0.0001 to 5% by weight.

62. A process as claimed in claim 61, wherein the silicon organofunctional silane is present in said solution in an amount of from 0.01 to 2% by weight.

63. A process as claimed in any one of claims 41 to 56 appended directly or indirectly to claim 30 wherein the silicon organofunctional silane containing amino and/or imino groups is present in said solution in an amount of from 0.0001 to 2% by weight.

64. A process as claimed in claim 63, wherein said silicon organofunctional silane is present in said solution in an amount of from 0.0005 to 1% by weight.

65. A process as claimed in claim 34 or 35 or any one of claims 36 to 58 when appended to claim 34 or 35 wherein the silicon functional silane is a compound of general formula: - - Si RV+I, in which R represents a straight chain or branched alkyl radical containing from 1 to 10 carbon atoms, Rvi represents a halogen atom or an alkoxy group containing from 1 to 8 carbon atoms which, when containing a plurality of carbon atoms may be inter- rupted by one or more hetero atoms, and n is an integer from 1 to 3.

66. A process as claimed in claim 65, wherein said compound is a propyl triethoxysilane, propyl trimethoxysilane, isopropyl dimethoxysilane or n-butyl or isobutyltriethoxy or trimethoxysilane.

67. A process as claimed in claim 10 or 12 or any one of claims 15 and 29 to 66 when appended to claim 10 or 12, wherein said solution has a total silane concentration of from 0.0001 to 1% by weight of the solvent.

68. A process as claimed in claim 67 when appended directly or indirectly to claim 12, wherein said solution has a total silane concentration of from 0.0001 to 7% by weight of the solvent.

69. A process as claimed in claim 68, wherein said solution has a total silane concentration of from 0.005 to 5.0% by weight of the solvent.

70. A process as claimed in claim 67 when appended directly or indirectly to claim 10, wherein said solution has a total silane concentration of from 0.01 to 10% by weight of the solvent.

71. A process as claimed in claim 70, wherein said solution has a total silane concentration of from 0.05 to 7% by weight of the solvent.

72. A process as claimed in any one of claims 36 to 60 when appended to any one of claims 10 to 29, wherein the silicon organofunctional silane is applied in an amount of from 0.0001 to 7% based on the weight of solvent present.

73. A process as claimed in claim 72, wherein the silicon organofunctional silane is applied in an amount of from 0.0005 to 5% based on the weight of the solvent present.

74. A process as claimed in claim 73 when appended to any one of claims 12 to 14, wherein the silicon organofunctional silane is applied in an amount of from 0.0001 to 2% based on the weight of the solvent present.

75. A process as claimed in claim 74, wherein the silicon organofunctional silane is applied in an amount of from 0.0005 to 1% by weight based on the weight of solvent present.

76. A process as claimed in any one of claims 72 te 75, wherein the silicon organofunctional silane is dispersed in a lacquer.

77. A process as claimed in any one of claims 10 to 16 or any one of claims 17 to 76 when appended directly or indirectly to any one of claims 10 to 16 wherein the silicon organofunctional silane and/or silicon functional silane is incorporated in a solvent which is toluene, xylene, petroleum ether, ethyl acetate, butyl acetate, isopropanol, methyl isobutyl ketone or a combination of two or more such solvents.

78. A process as claimed in any one of the preceding claims, wherein the bonding is effected at a temperature of from 120 to 2000 C.

79. A process as claimed in claim 78, wherein the bonding is effected at a temperature of from 120 to 1500C.

80. A process as claimed in claim 79, wherein the bonding is effected at a temperature of from 135 to 1450C.

81. A process for the production of laminated safety glass as claimed in claim 1, substantially as described in any one of the foregoing Examples 1 to 30.

82. A process for the production of laminated safety glass as claimed in claim 1, substantially as described in any one of the foregoing Examples 31 to 97.

83. Laminated safety glass whenever produced by the process claimed in any one of the preceding claims.