VAN HAPERT FRANS (NL)
| WO2014035942A1 | 2014-03-06 |
| EP0108631A2 | 1984-05-16 | |||
| EP2520896A2 | 2012-11-07 | |||
| EP2090427A1 | 2009-08-19 | |||
| US20140220286A1 | 2014-08-07 |
DR GÉRARD ET AL: "FUNDAMENTALS OF LAMINATING PROCESS AND QUALITY REQUIREMENTS", GLASS PROCESSING DAYS, 15 June 2000 (2000-06-15), XP055355466
| C L A I M S 1. A laminate of glass, comprising a first and a second glass sheet and an intermediate adhesive material, characterized in that the laminate is comprised of a successive positioning of a first glass sheet, a first layer of adhesive, a fixed intermediate lay- er, a second layer of adhesive, and a second glass sheet, with the proviso that the distance of each glass sheet to the fixed inter¬ mediate layer is less than 0.4 mm, wherein the adhesive comprises a material curable by UV radiation. 2. A laminate according to claim 1, wherein the thickness of the intermediate layer of adhesive material has a thickness of less than 0.4 mm, preferably less than 0.3 mm, more preferably less than 0.15 mm, in particular about 0.1 mm. 3. A laminate according to claim 1, wherein the glass plates each have a thickness in a range of from 0.3 mm, preferably at least 0.5 mm, and maximally 1.2 mm, preferably maximally 1.0 mm. 4. A laminate according to claim 1, wherein the glass plates each have a thickness in a range of more than 1.2 mm, preferably at least 2.0 mm, more preferably at least 2.5 mm, and maximally 5.0 mm, preferably maximally 4.0 mm. 5. A laminate according to claim 1, wherein the material of the fixed intermediate layer is chosen from a wood veneer, a stone, marble or granite layer or another natural material . 6. A laminate according to claim 1, wherein the material van de fixed intermediate layer is chosen from polytetrafluorethylene or another plastic material. 7. A laminate according to claim 1, wherein the thickness of the fixed intermediate layer is in the range of from at least 0.3 mm, preferably at least 0.5 mm, more preferably at least 0.8 mm, and maximally 3 mm, preferably maximally 2 mm, more preferably maxi¬ mally 1.3 mm, for example substantially 1 mm. 8. A laminate according to claim 1, wherein the adhesive is an acrylic resin based material. 9. A laminate according to claim 8, wherein the adhesive comprises an acrylate resin. 10. A laminate according to any of the preceding claims, wherein at least one of the glass plates is chosen from a chemically tem¬ pered glass and a thermally tempered glass. 11. A laminate according to claim 1, wherein the adhesive compris- es a dye. 12. A laminate according to claim 1, wherein the UV curing type adhesive is chosen from UV-curable acrylate resin and/or methacry- late resin compositions, in particular wherein the components are chosen from: polymers; elastomers; oligomers like polyester (meth) acrylates, urethane (meth) acrylates, epoxy (meth) acrylates, acrylic acid (meth) acrylates )) ; and (meth) acrylate monomers; with the proviso that the oligomers and monomers may be mono, di, tri or multifunctional. 13. A laminate according to claim 1, wherein photo initiators are present, which can suitably be selected from the following clas¬ ses: alfa-hydroxy ketones and mixtures thereof, alpha-amoni- ketones, benzyl dimethyl-ketal, BAPO and mixtures thereof, metal- locenes and benzophenone . 14. A method for producing a laminate according to any of claims 1 - 13, comprising the steps of: - (a) applying to a first main sur¬ face of a first glass sheet a liquid adhesive that is based on an acrylic resin in a thickness of less than 0.3 mm; - (b) position¬ ing on the surface of the first glass sheet that has been provided with the liquid adhesive a fixed intermediate layer with a thick- ness of less than 1.2 mm; - (c) laminating a second glass sheet on the fixed intermediate layer while using a liquid adhesive that is based on an acrylic resin and in a thickness of less than 0.3 mm, such that a first main surface of the second glass sheet is di- rected towards the fixed intermediate layer; and - (d) curing the liquid adhesive so as to obtain a cured adhesive between the first main surface of the first glass sheet and the fixed intermediate layer and between the first main surface of the second glass sheet and the fixed intermediate layer. 15. A method according to claim 14, comprising the step of subjecting the first major surfaces of the first and second glass plate to a silane treatment, preceding the steps (a) and (c) . 16. A method according to claim 14, comprising the step of pressing said both glass plates against each other during at least one of the steps (b) , (c) and (d) or in between at least two of these steps . 17. A method according to claim 16, comprising the step of press¬ ing the glass plates against each other so as to obtain a glass laminate with a total thickness that is less than 0.2 mm thicker than the thickness of said both glass plates, preferably less than 0.15 mm thicker, more preferably about 0.1 mm thicker. 18. A method according to claim 14, wherein the adhesive has a starting viscosity in the range of from 500 mPa.s to 800 mPa.s, preferably from 575 mPa.s to 750 mPa.s, in particular about 650 mPa . s . |
The present invention relates to a laminate according to the preamble of claim 1. The invention also relates to a method for producing such laminate.
This laminate is known in the art. For example, ballistic laminates are known that comprise two glass plates with an inter ¬ mediate plastic foil. The plastic foil positioned in between the two glass plates has a considerable thickness of at least a few millimeters so as to be able to provide sufficient strength to th laminate. Also, the glass panels usually have a thickness of at least one centimeter to provide sufficient strength. According to a known method for producing such laminate two glass plates are provided with an adhesive in a first step and maintained at a pre ¬ determined distance from each other and wherein in a further step a liquid material is poured in between the glass plates and subse ¬ quently cured.
This known laminate has limited advantageous characteristics Like very laminate that is produced from glass plates and a plas ¬ tic material, it has an improved shattering behavior than a mas ¬ sive glass panel. However, the method for producing this known laminate is labor intensive. Because of the extreme thickness, th laminate is not aesthetically appealing. For the same reason it cannot be applied in the aircraft and shipping industry, where weight saving is of great importance.
Another important disadvantage with respect to massive glass is that this known laminate is not fireproof. Especially in air ¬ craft and shipping applications fire safety is an important fac ¬ tor.
In the art, therefore, there is a need of an improved lami ¬ nate of the kind mentioned in the preamble.
The invention therefore aims at providing an improved lami ¬ nate of the kind mentioned in the preamble.
The invention especially aims at providing a laminate men ¬ tioned in the preamble that can be produced at low costs. The invention also aims at providing an improved laminate that offers fire safety such that it can be used in air transport. Preferably, the laminate also fulfils the marine fire safety regu ¬ lations .
The invention especially aims at providing a light weight laminate that fulfils the above mentioned goals.
So as to obtain at least one of the aforementioned ad ¬ vantages, according to a first embodiment the present invention provides a laminate comprising the features of claim 1. This lami ¬ nate has the advantage that it is much stronger than usual lami ¬ nates with a thicker intermediate adhesive layer.
According to a first aspect, the invention therefore relates to Derhalve heeft de uitvinding volgens een eerste aspect betrek- king op een laminaat van glas, omvattende een eerste en een tweede glasplaat met een daar tussenin gelegen hechtend materiaal, welk laminaat wordt gekenmerkt doordat het laminaat is gevormd van een opvolgende positionering van een eerste glasplaat, een eerste laag hechtmiddel, een vaste tussenlaag, een tweede laag hechtmiddel, en een tweede glasplaat, met dien verstande dat de afstand van elke glasplaat tot de vaste tussenlaag minder is dan 0,4 mm, waarbij het hechtmiddel een door UV straling uithardbaar materiaal omvat .
The layer of adhesive material in the laminate according to the present invention should be as thin as possible. Thus, the thickness of elk van de tussenliggende lagen hechtend materiaal bij voorkeur minder zijn dan 0.3 mm, more preferably less than 0.15 mm, in particular about 0.1 mm. It has shown that such ger- inge dikte van de lagen hechtend materiaal provides an excellent fire protection and flame retardancy. Glass plates of the present laminate are flame retardant as such, whereas the intermediate layer is flame retardant as well according to international stand ¬ ards for aviation. Even adhesives which are very flammable in the free state conform to these standards, when used in the laminate of the present invention. In the laminate, voldoen de lagen hecht ¬ middel eveneens aan de normering van brandveiligheid .
A suitable adhesive is of a type wherein the UV curing type adhesive is chosen from UV-curable acrylate resin and/or methacry- late resin compositions. Suitable components are chosen from: pol- ymers; elastomers; oligomers like polyester (meth) acrylates, ure- thane (meth) acrylates, epoxy (meth) acrylates, acrylic acid
(meth) acrylates )) ; and (meth) acrylate monomers. The oligomers and monomers may preferably be mono, di, tri or multifunctional. Suit ¬ able photo initiators are preferably selected from the following classes: alfa-hydroxy ketones and mixtures thereof, alpha-amoni- ketones, benzyl dimethyl-ketal , BAPO and mixtures thereof, metal- locenes and benzophenone .
The advantage of using a liquid UV curable resin for provid ¬ ing the connection between the glass plates after curing same, is that a simple short clamping of the glass plates suffices until a sufficient curing has been obtained due to curing of the UV cura ¬ ble resin. A long term thermal curing, as required in the art, not only requires a lot of energy but also yields large numbers of garbage due to insufficient clamping during the long cure at high temperature. It is an unexpected advantage that the present inven ¬ tion allows a much more secure clamping and positioning of the glass plates. Furthermore, glass laminate shapes may be produced that could not be produced hitherto, since now the clamping may be had in a UV lighting space at room temperature instead of in an oven. Design of laminated glass products, thereby may be obtained faster, cheaper and with more accuracy. In particular, the mutual clamping of the sheets of glass can be obtained without use of temporary clamping mechanisms, as is often the case with thermal curing, wherein double-sided tape is required to hold the glass sheets mutually fixed. Such a tape deteriorates the strength of the laminate.
Often, vacuum techniques must be used for yielding a good re ¬ sult in the glass laminates when laminating an adhesive layer at high temperature (each set of glass plates must be placed in a vacuum bag with vacuum valves) . Such is required to prevent "dis ¬ tortions" and "waves" in the glass. The end-result is only visible after hours of lamination. When using a UV curing technique, which only takes a few minutes, the product can be checked anytime and the failure rate will be significantly lower which results in a further reduction in cost price. These additional advantages of the method according to the present invention are a surprise and they offer significant benefits in the manufacture of, in particu ¬ lar, curved glass laminates.
The glass plates are preferably as thin as possible. It has surprisingly shown that the thickness of the glass plates espe- cially when applying a thin layer of adhesive as indicated above, allows to apply thinner glass plates than has been possible until now. Such provides huge advantages with respect to the weight of the glass laminate. The strength of the laminate however, is very large. In the laminate according to the invention, the glass plates each may have a thickness in a range of from 0.3 mm, pref ¬ erably at least 0.5 mm, and maximally 1.2 mm, preferably maximally 1.0 mm. Such yields a light weight but strong laminate that is es ¬ pecially useful in avionics and marine applications.
When a laminate with a very high strength is preferred, the glass plates each may have a thickness in a range of more than 1.2 mm, preferably at least 2.0 mm, more preferably at least 2.5 mm, and maximally 5.0 mm, preferably maximally 4.0 mm.
De tussenlaag kan uit een verscheidenheid aan materialen worden gekozen. De voorkeur gaat uit naar een materiaal dat een goede hechting heeft met het hechtmiddel dat wordt gebruikt en dat een goede hechting met glas dient te vertonen. Het is echter op verrassende wijze gebleken dat in hoofdzaak elk materiaal dat in geringe dikte kan worden vervaardigd geschikt is om als vaste tus ¬ senlaag te dienen. Met name heeft het de voorkeur dat het materi- aal van de vaste tussenlaag wordt gekozen uit een houtfineer, een steen-, marmer- of granietlaag of een ander natuurlijk materiaal. Dit levert een sterk laminaat op met een bijzonder esthetisch aantrekkeli jke uitstraling. De combinatie van een glasafwerking met een houten of stenen tussenlaag met een hechtlaag van geringe dikte in overeenstemming met de onderhavige uitvinding blijkt ex- treem sterk te zijn en een grote esthetische aantrekkeli jkheid te bezitten. Niettemin is het gewicht zeer laag in vergelijking met een volledig stenen plaatvormig materiaal, aangezien het laminaat volgens de uitvinding bij gelijke dikte een hogere sterkte bezit. Onderhoud van het laminaat volgens de uitvinding is bovendien makkelijker dan onderhoud van steen, zoals graniet of marmer, en zeer veel makkelijker dan van hout . Daarnaast is het laminaat vol- gens de onderhavige uitvindmg m alle gevallen brandvertragend en vlamdovend .
De vaste tussenlaag kan volgens een ander aspect van de uitvinding geschikt worden gevormd van polytetrafluorethyleen (PET) of een andere kunststof. Kunststof, met name maar niet uitsluitend PET, heeft het voordeel dat dit materiaal een grote sterkte aan het laminaat verschaft, zelfs bij toepassing in ger- inge dikte en omdat het bij een dergelijke geringe dikte
uitstekende vlamdovende en brandvertragende eigenschappen ver ¬ schaft, zelfs wanneer de kunststof op zich brandbaar is.
Een ander voordeel van een kunststof tussenlaag is dat het eenvoudig kan worden voorzien van een bedrukking met een of meer- dere kleurstoffen . Een bijzonder voordelige uitvoeringsvorm van de uitvinding wordt derhalve gevormd door een laminaat met een daarop aangebrachte afbeelding.
De voordelige eigenschappen betreffende de sterkte van het laminaat, de brandwerende eigenschappen en de brandvertraging worden in het bijzonder verkregen wanneer de dikte van de vaste tussenlaag is gelegen in het traject vanaf ten minste 0,3 mm, bij voorkeur ten minste 0,5 mm, met meer voorkeur ten minste 0,8 mm, en tot maximaal 3 mm, bij voorkeur maximaal 2 mm, met meer voor ¬ keur maximaal 1,3 mm, en bijvoorbeeld in hoofdzaak 1 mm is.
Several adhesives that are known in the art can be used for producing the laminate according to the invention. Especially pre ¬ ferred is an adhesive that comprises an acrylic resin based mate ¬ rial, for example a modified acrylic resin.
It is especially preferred that the adhesive comprises an acrylate resin.
An improved safety of the present laminate may be obtained with a laminate wherein at least one of the glass plates is chosen from a chemically tempered glass and a thermally tempered glass. It is especially preferred that both glass plates are chemically cured. A special preference relates to an embodiment wherein both glass plates are both chemically and thermally cured such that a strong and safe material is obtained.
Volgens een verder aspect heeft de uitvinding betrekking op een werkwijze voor het vervaardigen van een laminaat zoals hi- ervoor genoemd, omvattende de stappen van: - (a) het op een eerste hoofdoppervlak van een eerste glasplaat aanbrengen van een vloeibaar hechtmiddel op basis van een acrylhars in een dikte van minder dan 0,3 mm; - (b) het op de met vloeibaar hechtmiddel beklede oppervlak van de eerste glasplaat positioneren van een vaste tussenlaag met een dikte van minder dan 1,2 mm; - (c) het lamineren van een t eede glasplaat op de vaste tussenlaag onder toepassing van een vloeibaar hechtmiddel op basis van een
acrylhars in een dikte van minder dan 0,3 mm, zodanig dat een eerste hoofdoppervlak van de tweede glasplaat naar de vaste tus ¬ senlaag is gericht; en - (d) het doen uitharden van het vloeibare hechtmiddel ter verkrijging van een uitgehard hechtmiddel tussen het eerste hoofdoppervlak van de eerste glasplaat met de vaste tussenlaag en tussen het eerste hoofdoppervlak van de tweede glasplaat met de vaste tussenlaag. Hiermee wordt het laminaat vol- gens de uitvinding verkregen, met de hiervoor genoemde voordelige effecten en resultaten.
So as to improve the adherence of the adhesive to the glass surface, it is preferred that the method comprises the step of subjecting the first major surfaces of the first and second glass plate to a silane treatment, preceding de stappen (a) en (c) .
An optimum adhesion is obtained and a layer of adhesive that is as thin as possible, the method according to the invention com ¬ prises the step of pressing said both glass plates against each other during at least one of the steps (b) , (c) en (d) of tussen ten minste een van deze stappen in. De capillaire werking van de zeer geringe ruimte tussen de platen zorgt ervoor dat een geringe hoeveelheid hechtmiddel tussen de respectievelijke glasplaat en de vaste tussenlaag opgesloten zal blijven, zelfs wanneer de voor glas maximaal toelaatbare drukkracht (voordat het glas bezwijkt) wordt gebruikt om de verschillende lagen van het laminaat tegen elkaar te persen.
Preferably, this press step is performed such that it com ¬ prises the step of pressing the glass plates against each other so as to obtain a glass laminate with a total thickness that is less than 0.2 mm thicker than the thickness of said both glass plates, preferably less than 0.15 mm thicker, more preferably about 0.1 mm thicker. This yields a very strong laminate with a low weight that also is flame proof and flame retardant.
So as to obtain a suitable flowing of the adhesive on the glass surface the adhesive is preferably applied as a liquid on at least one of the glass plates. Such is especially suitable per ¬ formed when the adhesive has a starting viscosity in the range of from 500 mPa.s to 800 mPa.s, preferably from 575 mPa.s to 750 mPa.s, in particular about 650 mPa.s.
Surprisingly, it has shown that the present laminate, despite the thin layer of adhesive, exhibits a high flexibility. Neverthe ¬ less, the strength is also surprisingly high.
Hereafter, the invention will be described by way of an example .
Impact resistance:
The impact resistance of the present laminate was tested ac ¬ cording to the Ball Impact Test ANS/UL61965-2009.
Herein, the laminate is positioned vertically in a frame. A steel ball, with a minimum weight of 535,24 gram, is thrown against the laminate.
The laminate to be tested was made of two glass plates with a thickness of 0.55 mm each met een PET tussenlaag met een dikte van 1 , 0 mm . The layers of adhesive were based on acryl and cured by means of UV radiation. The thickness of the adhesive layers was 0.1 mm .
There was no damage of the glass surface. Also, the adhesive layers had no damage. Fire resistance:
The laminate as tested in the impact test with glass plates with a thickness of 0.55 mm each and an intermediate adhesive lay ¬ ers of 0.3 mm en een PET tussenlaag van 1,0 mm dik, was used for determining the fire resistance. The laminate is heated from one side wherein the temperature is measured at the other side.
These tests were performed according to the Heat Release test JAR/FAR/CS 25, App . F, Part IV. It has been found that the laminate according to the inven ¬ tion amply satisfies the Heat Release test.
Such a result for a laminate having such a small thickness is excellent and makes the product extremely suitable for use in the aviation and shipping.
Combustibility :
The laminate as tested in the impact test was also used for determining the combustibility according to FAR/JAR/CS 25, App. F, Part I. The laminate is heated at its side edges with a flame of minimally 980 °C and it is determined whether the material itself further illuminates or extinguishes.
The results are excellent and unexpected in comparison to conventional laminates containing an acrylic resin as a bonding agent.
The results fulfilled the limit.
Strength :
The laminate as tested in the impact test and combustibility was also used for determining the strength of the laminate accord ¬ ing to the invention. This test took place according to the so- called Abuse Load Test.
A weight of 135 kg is positioned on a laminate that is fas ¬ tened in a frame. The present laminate withstood this test without any damage.
The invention is not limited to the embodiments as described herein and as shown in the drawing. The invention is limited only by the appending claims.
The invention also embodies all combinations of features that have been described independently from each other.
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