DK163039B - LAMINATED SAFETY PANEL - Google Patents

Abstract

1. A laminated pane comprising only a glass sheet and a layer of transparent plastics material, characterised in that the layer of transparent plastics material has properties of absorption of energy and interior protection defined by a scratch resistance greater than 20 g measured with the Erichsen type 413 apparatus and an abrasion resistance according to European Standard R43 such that the haze difference is less than 4% and at a thickness of about 0.5 mm a flow stress sigma y at -20 degrees C not exceeding 3 daN/mm**2 , a rupture stress sigma R at +20 degrees C of at least 2 daN/mm**2 , a lengthening at rupture epsilon R at +20 degrees C from 250% to 500%, and a tear resistance Ra at +20 degrees C of at least 9 daN/mm**2 , and in that the layer of plastics material is formed essentially of a polyurethane obtained by continuous reactive casting on a flat horizontal support of a reaction mixture of an isocyanate component and a polyol component, the isocyanate component comprising at least one aliphatic or cycloaliphatic di-isocyanate or a di-isocyanate prepolymer, this component having a viscosity measured at +40 degrees C less than about 5 Pas, the isocyanate component containing urea functions, the content of urea being up to 10% of the total weight of isocyanate component, the urea content preferably being from 5 to 7%, and the polyol component comprising at least one long difunctional polyol of molecular weight from 500 to 4000 and at least one short polyol as a chain lengthening agent, the ratio of isocyanate group equivalents to hydroxyl group equivalents is about 1, and the proportions between the different polyols are selected so that the number of hydroxyl group equivalents due to the short diol represents from 20 to 70% of the total hydroxyl groups.

Description

DK 163039 B

The invention relates to a novel laminated pane containing a glass lamella and a transparent plastic layer, wherein the transparent plastic layer shows energy-absorbing properties and internal protection defined by a scratch resistance of more than 20 g measured with ERICHSEN type 413 apparatus and such wear resistance according to the European standard R43, that the clarity deviation is less than 4%, and wherein the plastic layer at a thickness of at least approx. 0.5 mm shows a flow threshold voltage σ at -20 ° C lower than 2 y q

10 or equal to 3 daN / mm, a breaking voltage aD at +20 C

2 K

greater than or equal to 2 daN / mm, a rupture extension at + 20 ° C located between 250 and 5001, a resistance to initial tearing R at + 20 ° C greater than or cl equal to 9 daN / mm.

15 Laminated panes designated security panes generally consist of two glass louvers and an intermediate layer of energy absorbing properties, usually of polyvinyl butyral. One of the drawbacks of this type of laminated pane when used as a vehicle windshield is that the 20 edges of the inside broken glass that appear in the event of a collision with the head of a person sitting in the vehicle can cause tears and other damage. For example, it is proposed, for example, in French Patent Nos. 2,187,719 and 2,251,608 to this inner glass laminate to apply a plastic laminate formed essentially of a thermosettable polyurethane having anti-tearing properties. Furthermore, this plastic lamella is self-healing, ie. it is a material in which surface tears or local imprints quickly disappear, the rate of disappearance being a function of the nature of the tear and the temperature of the plastic material.

Also, for example, in French Patent No. 2,398,606, a laminated pane containing a glass lamella, a thermoplastic layer having energy-absorbing properties and a coating layer that is self-healing and scratch-resistant and formed essentially of a thermoset polyurethane are proposed. In this type of pane, each of the layers fulfills a specific function in that

DK 163039 B

2 thermoplastic layers essentially fulfill the function of absorbing energy, but are not sufficiently resistant to abrasion or external agents, and the coating layer fulfills the function of protecting the energy-absorbing layer, but does not exhibit good energy-absorbing properties.

Previously, for example, U.S. Pat.

3,509,015 and 3,808,077 proposed laminated panes containing a glass lamella and a single plastic layer having energy-absorbing properties. This type of pane has apparently never been fully satisfactory, undoubtedly due to insufficient resistance to abrasion and scratching of the plastic layer used as the outer layer.

15 It is generally accepted that a laminated pane structure containing a single plastic layer, which at one time has energy-absorbing properties and good resistance to scratching and attack by external agents, would hardly be able to function satisfactorily.

One skilled in the art will find some incompatibility between the energy-absorbing function and the scratch resistance that a single layer should be able to fulfill. For a layer to exhibit energy-absorbing properties, it is generally accepted that it must exhibit a substantially thermoplastic character. On the other hand, for a layer to have good scratch resistance, it is believed that it must exhibit a substantially thermosetting character with a cross-linked structure. These mechanical properties associated with thermoplastic or thermoset are described, for example, in French Patent No. 2,398,606 and in European Patent No. 0.054,491.

A single plastic layer has now been found which, in a laminated pane structure in which it is connected to a glass lamella, fulfills the energy-absorbing function, protects against glass splinters and further exhibits good resistance to abrasion and scratching as well as to various attacks by external means. .

DK 163039 B

Accordingly, the laminated pane of the invention is characterized in that the plastic layer is formed mainly of a polyurethane obtained by continuous reactive pouring on a planar horizontal support of a reaction mixture of an isocyanate component and a polyol component, the isocyanate component contains at least one aliphatic or cycloaliphatic diisocyanate or a diisocyanate prepolymer, which component has a viscosity measured at 40 ° C lower than ca. 500 Pa * s, 10 wherein the isocyanate component contains urea functions, the urea content being able to reach 10% of the total weight of the isocyanate component and preferably being between 5 and 7% and the polyol component containing at least one long difunctional polyol having a molecular weight located between 500 and 4000 and at least one short diol as a chain extender, the isocyanate component and the polyol component being used in such amounts that the ratio of the isocyanate equivalent groups to the hydroxy equivalent groups is approximately equal to 1, 20 whereby the mixing ratios of the various polyols are selected such that the number of hydroxy equivalent groups resulting from the short diol represents 20-70% of the total hydroxy groups.

Reactive pouring means pouring in the form of a layer or film a liquid mixture of the components in the form of monomers or prepolymers followed by a polymerization of this mixture by the action of heat. This reactive pour which imparts to the layer its good mechanical and optical properties is described in more detail below.

The mixing ratios of the polyurethane components are chosen such that a stoichiometric equilibrated system is preferably obtained, i.e. that the ratio of the equivalent groups of NCO provided with the diisocyanate component to the equivalent groups of OH provided by the polyol component, i.e. the long polyol (s) and the short diol (s) are of the order of 1. When

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4 the NC0 / 0H is lower than 1, the more it decreases, the sooner the mechanical properties desired for use become rapidly unsatisfactory. When all the components of the polyurethane are difunctional, the lower gram of the ratio of NC0 / OH, to obtain satisfactory mechanical properties, is located at approx. 0.9. When at least one of the components is tri-functional, said lower limit can be lowered to approx. 0.8.

When the ratio of NCO / OH is greater than 1, the more it increases, the more certain mechanical properties of the layer obtained by reactive pouring are reinforced, for example, the layer becomes more rigid, but considering that the isocyanate component is more expensive than the polyol component, the choice of a ratio of NCO / OH 15 is essentially equal to a good compromise between the properties obtained and the cost.

The mixing ratios of the long polyol to the short diol may vary as a function of the desired properties, as discussed below, but as mentioned, the number of equivalent groups of OH derived from the short diol represents 20-70% of the total equivalent groups of that mixture. constituting the polyol component in the case where the ratio of the equivalent groups of NCO to the groups of OH is of the order of 1. When the amount of 25 short diol is raised, the layer becomes harder and its module is generally raised.

In particular, the diisocyanates useful in the present invention are selected from the following difunctional aliphatic isocyanates: hexamethylenedi isocyanate (HMDI), 2,2,4-trimethyl-1,6-hexanedisocyanate (TMDI), bis-4-isocyanatocyclohexylmethane (Hylene W ), bis-3-methyl-4-isocyanatocyclohexylmethane, 2,2-bis (4-isocyanatocyclohexyl) propane, 3-isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate (IEDI), m-xylylenediisocyanate (XDI), m- and p-tetramethylxylylene diisocyanate (m- and p-TMXDI), trans-cyclohexane-1,4-diisocyanate (CHDI), 1,3- (diisocyanatomethyl) -cyclohexane (hydrogenated XDI).

Preferably, IPDI is used, especially because of the manufacturing cost.

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5

As mentioned, for the plastic layer in the laminated pane of the invention, an isocyan component containing urea functions is used. These -of features enhance certain mechanical properties 5 rough. layer. The content of urea can represent up to approx. 10% of the total weight of the isocyanate component with urea functions. The urea content is preferably between 5 and 7% of the total weight of said component. For the above reason, 3-isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate containing urea functions (IPDI and derivatives) is preferably used.

The useful long polyols are selected from polyether diols or polyester diols having a molecular weight of 500-4000, the polyester diols being esterification products of a diacid such as adipic acid, succinic acid, palmitic acid, azelaic acid, sebacic acid or ophthalic acid, and a diol. , such as ethylene glycol, 1,3-propanediol, 1,4-butanediol or 1,6-hexanediol, and the polyether diols have the general formula:

Bi0 <CH2> Å0H

where n = 2-6, and m as the molecular weight is in the range of 500-4000, or the polyether diols have the general formula:

H {AND - CH, + OH

m Hl 25 where m as the molecular weight is in the range 500-4000. Polycaprolactone diols can also be used.

Preferably, a polytetraraethylene glycol (n = 4) having a molecular weight of about 1000 is used.

The useful chain extender agents are short diesels, such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-, 1,3- or 1,4-butanediol, 2,2-dimethylene. 1,3-propanediol (neopentyl glycol), 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1,12-dodecanediol, cyclohexanedimethanol, bisphenol A, 2-methyl-2 , 4-pentanediol, 3-methyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, 2 -butyn-1,4-diol, 1,4-

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6 butenediol and decyndiol substituted and / or etherified 7 hydroquinone bis hydroxyethyl ether, bisphenol A etherified with two or four groups of propylene oxide, dimethylol proponic acid. In general, the shorter the diol, the harder the layer.

Preferably, 1,4-butanediol is used which is a good compromise to obtain a layer that is neither too hard nor too soft and which is desired for the present type of application.

As mentioned in the plastic layer of the laminated pane according to the invention, formed mainly by reactive pouring on a flat horizontal support, which reactive pouring already described in French Patent No. 2,442,128 to obtain a thermosettable polyurethane layer from a mixture of 15 trifunctional components, surprisingly in the case of the invention with difunctional starting components, provide a layer that is not completely thermoplastic when the ratio of the groups NC0 / OH is substantially equal to or greater than 1.

The reactive pouring involves a rapid polymerization reaction for the layer to form within periods compatible with an industrial fabrication.

This necessitates an elevated temperature of the order of approx. 100-140 ° C, which is a temperature at which secondary branching reactions occur, for example providing allophanate and / or biuret groups between the urethane chains, such as:

DK 163039 B

7 - R-NH-CO-O-R '- O -

OCN - R - NCO

- R-NH-CO-O-R * - O - 5 ___ - R M - CO ^ O - R * - O - 'i /' CO # allophanate • NH / »\> R / v-"

10 NH

CO · \ - R - N - CO - R * - O - 1Ί or - R "- NH - CO - NH - R" -

20 OCN - R - NCO

-R "- NH - CO - NH - R" -

^ I

- R "YY-C0 ~ - NH V R" - i 1 /

in CO

. 1 ^ 25 * VNH biuret

R

NH

in

CO

- R "- N - CO - NH - R" - 30 Under these operating conditions, the product obtained, even with difunctional components, when the ratio NCO / OH is substantially equal to or greater than 1, as indicated above, is not completely thermoplastic.

It is in fact immiscible and insoluble in most solvents for polyurethanes such as tetrahydrofuran or dimethylformamide. This is no disadvantage as the layer is already formed. On the contrary, obtained as one

DK 163039 B

8 advantage improved mechanical properties of the layer, in particular with respect to the flow threshold stress fracture stress fracture elongation eR, resistance to initial tearing R_, the scratch resistance measured by ERICHSEN test as

Cl 5 described below, or the wear resistance, compared to an equivalent system polymerized at low temperature where only linear polycondensation occurs.

When the NCO / OH ratio is less than 1 and of the order of 0.8 to 0.9, only a negligible degree of cross-linking of the type described above occurs.

By providing the polyurethane layer in the laminated pane of the invention, the polyol component may contain a small amount of at least one polyol having functionality higher than two and especially aliphatic monomeric triols such as glycerol, trimyhylol propane, polyether chain triols, polycaprol triols with the molecular weight of these triplets generally being between 90 and 1000, mixed polyether / polyester polyols having a functionality greater than 2, for example a functionality lying between 2 and 3. Addition of a polyol having a functionality greater than 2 further promotes bridge links between the chains of the polyurethane and thus can further improve the cohesion of the layer.

The mixing ratios of the long polyol, the 25 short diol, and optionally the polyol with a functionality greater than 2 may vary with the desired properties. Generally, such blending ratios are chosen that, for 1 equivalent of hydroxyl, the long polyol represents approx. 0.30 to 0.45 equivalent, the short diol represents approx. 0.2 to 0.7 equivalent, and the polyol having a functionality greater than 2 represents approx. 0 to 0.35 equivalent. Under these conditions, the layer exhibits the aforementioned mechanical characteristics measured according to the standards AFNOR / NFT 46.002, 51.034 and 54.108: 35. Part of the polyol component may optionally be replaced with another product with active hydrogens such as an amine.

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9

According to an embodiment of the plastic layer in the laminated pane according to the invention, the isocyanate component can be used in limited quantities, for example less than approx. 15% in NCO equivalents contain a triisocyanate such as a blur of isocyanate or a triisocyanurate.

In order to fulfill all the required functions, the polyurethane layer of the invention must have a thickness generally greater than 0.4 mm and preferably greater than 0.5 mm.

The layer of the invention may contain various additives which generally serve to facilitate its preparation by reactive pouring. It may contain a catalyst such as a tin catalyst, for example dibutyltin dilaurate, tributyltin oxide, tin octoate, an organo-mercury catalyst, for example, phenylmercury ester, an amine catalyst such as diazabicyclo- (2,2,2) -octane or L- (l, 8-diazabicyclo (5,4,0)) - 7-decene. The layer may contain a stabilizer such as bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate or a phenolic antioxidant.

The layer may also contain a coating agent such as a silicone resin, a fluoroalkylated ester or an acrylic resin.

The invention is further described by the following examples in the manufacture of laminated glazing and the plastic layer used for this manufacture.

Example 1

To prepare the plastic layer, the polyol component is prepared by mixing a polytetramethylene glycol having a molecular weight of 1000 (for example, the product sold under the name Polymeg 1000 by the company QUAKER OATS) with 1,4-butanediol, the mixing ratios of the two constituents are such that the polytetramethylene glycol provides 0.37 equivalent of hydroxy groups, while the 1,4-butanediol provides 0.63 equivalent thereof.

DK 163039 B

In the polyol component, a stabilizing agent is incorporated in an amount of 0.5% by weight of the total mass of the polyol component and the isocyanate component, a coating agent in an amount of 0.05% by weight calculated in the same manner and a catalyst of dibutyltin diurea in an amount of 0.02% by weight calculated in the same manner as above.

The isocyanate component used is 3-isocyanato-methyl-3,5,5-trimethylcyclohexylisocyanate (IPDI) exhibiting urea functions, obtained by partial hydrolysis of 10 IPDI, and having a content of NCO groups of approx. 31.5% by weight.

The components are used in such quantities that the ratio of NCO / OH is 1. After deaeration of the components in vacuo, the mixture is brought to 40 ° C by means of a pouring head such as that in French patent no.

15,347,170 described poured onto a mobile glass carrier coated with a separation agent. In this way, a layer with a uniform thickness of approx. 0.755 mm, which is subjected to a polymerization period, i.e. for a temperature of 120 ° C for approx. 25 minutes.

After polymerization, the layer is taken off the glass support to form a slab which can be stored or used immediately after to produce laminated panes.

To make the pane, the plastic laminate is assembled with a hardened glass slab of 2.6 mm thick.

25 The glass may be hardened or hardened. This assembly can take place in two stages, a first stage consisting of a preliminary assembly by passing the elements contained in the pane between two calender rolls to which the apparatus described in European Patent No. 0015209 can be used and a second stage consists of in placing the laminated product in an autoclave wherein

1 hour is exposed to a pressure of approx. 10 bar at a temperature of approx. 135 ° C. This autoclave period can optionally be replaced by a period in the oven without pressure.

35 The won pane exhibits excellent optical quality and perfect transparency.

The adhesion obtained between the glass slat and the plastic layer is measured by a peel test described below.

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11

A band with a width of 5 cm is cut on the cover layer. The end of the strip is separated and a traction applied perpendicular to the pane surface at a rate of 5 cm per minute. The operation is performed at + 20 ° C. Note 5 is the mean tensile force required to separate the belt. In this way, a traction force of 10 daN / 5 cm was found.

Shock resistance tests at various temperatures were performed on the pane manufactured according to the example.

10 An initial shock resistance test is performed at + 20 ° C

with a steel ball of 2,260 kg (large ball test), which is allowed to fall on the central part of a sample of laminated pane with a side edge of 30.5 cm and held on a rigid frame. The approximate height is determined for which 90% of the samples tested at a selected temperature withstand the drop of the ball without being penetrated.

For the laminated pane according to the example, the value obtained was 12 meters.

Another shock resistance test is conducted. with a 20 steel ball of 0.227 kg and a diameter of 38 mm. A test is carried out at a temperature of -20 ° C. Another test is carried out at a temperature of + 40 ° C. The values obtained were 12 m and 11 m respectively.

According to the current European standard R43, the desired results are at least 4 m for the big ball, at least 8.5 m for the small ball at -20 ° C and at least 9 m for the small ball at + 40 ° C.

The scratch resistance is measured by the scratch test known under the designation "MAR resistant test" and is made with 30 ERICHSEN type 413 apparatus. The load to be applied to a diamond head is measured to introduce a permanent scratch on the plastic layer together with the glass support. The load must be greater than or equal to 20 g for the plastic layer to have the property of self-healing.

The scratch resistance measured by this test was for the pane according to the example of 32 g.

The wear resistance is measured according to European standard R43. For this purpose, a total windscreen sample is exposed

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12 for abrasion using a grindstone. After 100 wear trips, a spectrophotometer deviation of clarity between the worn part and the non-worn part is measured with a spectrophotometer. Clarity deviation (Δ clarity) must be less than 4% for layer 5 to have anti-wear quality.

The layer according to the example showed a clearance deviation of 0.94%.

The pane according to the example showed all the characteristics which make it suitable for use as a vehicle front pane.

Example 2

The same procedure was used as in Example 1 except that the polyol component was formed from a mixture of polytetramethylene glycol having a molecular weight of 1000, 1,4-butanediol and polycaprolacton triol (for example, the product sold under the designation Niax 301 by UNION CARBIDE ) in such respective amounts that 0.35, 0.45, 20 and 0.20 equivalent of hydroxyl were used for a total of one equivalent of hydroxyl.

A layer having a thickness of 0.70 mm was prepared. The won pane showed mechanical and optical characteristics that were fully satisfactory. The values measured by the different experiments were as follows; 25 - an adhesion of 11 daN / 5 cm, - values of 8 m for large ball and 11 m and 11 mm for small ball at -20 ° and + 40 ° C respectively, - a scratch resistance of 35 g and - a deviation of clarity of 1.2%.

The pane made according to this example was thus suitable for use as a windshield.

Example 3

The same procedure as in Example 2 35 was used except that the mixing ratios of the different polyols were such that 0.35, 0.55 and 0.10 equivalent of hydroxyl from the long polyol, respectively, were used for a total of one equivalent of hydroxyl.

Claims (9)

1. A laminated pane containing a glass lamella and a transparent plastic layer, wherein the transparent plastic layer shows energy absorbing properties and internal protection defined by a scratch resistance of more than 20 g measured with ERICHSEN type 413 apparatus and such wear resistance according to European standard R43, that the deviation of clarity is less than 4%, and wherein the plastic layer at a thickness of at least approx. 0.5 mm shows a flow threshold voltage σ at -20 ° C lower than or equal to 3 daN / mm ^, a breaking-yo 2 voltage σΏ at +20 C greater than or equal to 2 daN / mm, Xv a breaking elongation at + 20 ° C located between 250 35 and 500%, a resistance to initial tearing Ra at + 20 ° C greater than or equal to 9 daN / mm, characterized in that the plastic layer is formed mainly of a polyurethane obtained by continuous reactive pouring DK 163039 B on a planar horizontal carrier of a reaction mixture of an isocyanate component and a polyol component, the isocyanate component containing at least one aliphatic or cycloaliphatic diisocyanate or a diisocyanate prepolymer having a viscosity measured at 40 ° C lower than ca. 500 Pa · s, wherein the isocyanate component contains urea functions, the urea content being capable of reaching 10% of the total weight of the isocyanate component and preferably being between 10% and 7% and the polyol component containing at least one long difunctional polyol having a molecular weight between 500 and 4000 and at least one short diol as a chain extender, the isocyanate component and the polyol component being used in such amounts that the ratio of the isocyanate equivalent groups to the hydroxy equivalent groups is about equation 1, whereby the mixing ratios of the various polyols are selected such that the number of hydroxy equivalent groups due to the short diol represents 20-70% of the two hydroxy groups. Laminated pane according to claim 1, characterized in that the polyol component further contains at least one polyol with a functionality greater than 2. A laminated pane according to claim 1 or 2, characterized in that the isocyanate component contains 3-isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate. Laminated pane according to any one of claims 1-3, characterized in that the isocyanate component is formed mainly of 3-isocyanate methyl-3,5,5-trimethylcyclohexylisocyanate containing urea groups and that the polyol component is formed mainly of polytetramethylene glycol and 1,4-butanediol. 5. A laminated pane according to claims 2-4, characterized in that the polyol having a functionality greater than 2 is a polycaprolactone triol. DK 163039 B 5 An adhesion of 11 daN / 5 cm, values of 10 m for large ball, 13.5 m and 13.5 m for small ball at -20 ° C and + 40 ° C, a scratch resistance of 25 g and a blur deviation at wear of 1.2%. Thus, the pane made according to this example was suitable for use as a windshield. Example 4 (Comparison) The same procedure as in Example 1 was used except that the polymerization of the layer was carried out at a temperature of only 60 ° C for 20 hours. Shock resistance tests gave a small ball value at -20 ° C of 6.5 m, which is inadequate. This example, compared to Example 1, shows the effect of the polymerization temperature 20 used during the reactive pour. In the present example, this temperature was too low. Laminated pane according to any one of claims 1-5, characterized in that, for a total of one equivalent of hydroxyl, the long polyol represents 0.30-0.45 equivalent, the short diol represents 0.2-5.7 equivalent and the polyol having a functionality greater than 2 represents 0-0.35 equivalent. Laminated pane according to any of claims 1-6, characterized in that the polyurethane layer with energy absorbing properties and internal protection contains additives such as a catalyst, a coating agent or a stabilizing agent. Laminated pane according to any one of claims 1-7, characterized in that the transparent plastic layer is obtained by reactive pouring using a polymerization temperature above 80 ° C. 'Ninth Laminated pane according to any one of claims 1-8, characterized in that the isocyanate component further contains at least one triisocyanate.