MXPA99005366A - Damped glass and plastic laminates - Google Patents

Abstract

The present invention provides a damped glass and/or plastic laminate which damps both sounds and vibrations which is particularly useful for vehicle windows such as automobile windows, aircraft windows, watercraft windows, etc.;office building windows;airport windows;etc. The laminate (2) comprises outer rigid layers (4) such as glass or plastic and at least one inner layer (8) of vibration damping material (6) and a flexible plastic material such as polyvinyl butyral.

Description

REDUCED GLASS AND PLASTIC LAMINATES FIELD OF THE INVENTION The present invention is concerned with a cushioned glass and / or plastic laminate that dampens sounds and vibrations that is particularly useful for vehicle windows such as automobile windows, train windows, windows of aircraft, boat windows, etc.; windows of office buildings, airport windows; etc.

BACKGROUND OF THE INVENTION U.S. Patent No. 5,368,917 issued to Rehfeld, et al., Assigned to Saint Gobain Vitrage International, discloses an acoustic glazing for a vehicle, especially a motor vehicle. These items serve to dampen aerodynamic noise (column 1, lines 49-51) at frequencies above 800 Hz. The patent? 917 describes windscreens having two sheets of glass separated by a sheet of plastic or interlayer of air space. Additional laminated glass constructions useful for noise isolation are described in JP07081982, JP06191905, and JP06166551. Other laminates are described in U.S. Patent Nos. 4,427,734 and 5,154,953 and JP 06206739 and JP 05310450.

REF .: 30434 A conventional safety glass is discussed in the MCGRA-HILL ENCYCLOPEDIA OF SCIENCE AND TECHNOLOGY, volume 16, pages 3 to 4 (1986). It is defined as a unitary structure formed of two or more sheets of glass between each of which a plastic sheet, usually of polyvinyl butyral, is interposed. According to the reference, it normally occurs when first mounting two clean and dry sheets of glass on plates and a sheet of plastic under light pressure to produce a gap-free pressing. Then, the laminate is pressed at a pressure of 0.5 to 1.5 megapascals) (75-225 pounds / inches2) under heat at a temperature of 115 to 150 ° C (239-302 ° F) for a sufficient time to bind. The reference indicates that for installation in surface vehicles the finished laminated glass is approximately 6 mm (1/4 inch) thick. For aircraft use, the finished glass laminate is thicker. The plastic interlayer has the ability to give way instead of breaking under impact. Due to this property and the adherence of glass to plastic, laminated glass presents less danger of cantilevered or scattered glass fragments in case of damage than that of an equal glass thickness. According to the reference, however, the non-rigid plastic layer decreases the modulus of rupture of laminate to approximately 60 percent of that of monolithic glass at room temperature. The thermoplastic interlayer, also towards the other properties of the safety glass, appreciably dependent on temperature. Optionally, the safety glass substantially has the properties of the glass sheets' from which it is made. However, according to the reference, at a temperature greater than about 70 ° C (160 ° F) the organic plastic may deteriorate. Most safety glass is used in automotive vehicles where the plastic interlayer is 0.75 mm (0.030 inches) thick. According to the reference it is also used on ships, locomotives, rail cars, aircraft, safety glasses and peepholes. Formed from tempered glass and in multiple layers and built to a greater thickness, the laminate is used in structures resistant to bullets in banks, jewelry display cases, vehicles and windows of test chambers. The glass or plastic can be dyed to provide color filtration. Safety glass is also discussed in "Questions &Answers, Answers To." The Most Asked Questions About Residential Glass: Its Applications, Features and Benefits ", Safeflex Home Page 10/25/96, pages 1- 7, .http: // ww.monsanto.com // saflex / faq /.

A laminated glass is described in U.S. Patent No. 5,532,528, assigned to Saint-Gobain Vitrage International.

Brief Description of the Invention Although glass laminates have been available that dampen higher frequencies such as 800 to 1000 Hz, there is a need for a laminate that dampens lower frequencies of less than 200 Hz in addition to frequencies in the range of 800 to 1000 Hz (normally from 20 to 1000 Hz at a temperature of -10 to 50 ° C). The present invention provides such a laminate. The article of the present invention provides damping in a wide frequency that includes the range of 20 to 200 Hz. The present invention provides a new article comprising a laminate, wherein the laminate comprises: a) a first rigid layer formed of a material selected from the group consisting of glass and plastic; b) a second rigid layer formed of a material selected from the group consisting of glass and plastic; c) a layer (s) of vibration damping material positioned between the first rigid layer and the second rigid layer; d) a first layer of a flexible plastic, positioned between the first rigid layer and the layer (s) of vibration damping material, wherein the first layer of flexible plastic is of such a nature that a test construction of the flexible plastic layer laminated between two sheets of annealed glass, each sheet of annealed glass has a thickness of 2.5 miti, pass it the test of the Consumer Product Safety Commission 16CFR, Part 1201, Category I; and e) optionally, a second layer of a flexible plastic positioned between the second rigid layer and the layer (s) of vibration damping material, wherein the second layer of flexible plastic is of such a nature that a test construction of the second layer of flexible plastic laminated between two sheets of annealed glass, each sheet of annealed glass has a thickness of 2.5 rom, pass it the test of the Consumer Product Safety Commission 16CFR, Part 1201, Category I. The form of glass of the article of the present invention has the advantage that it has a superior damping (especially for the temperatures and powers experienced by windshields and side glasses in automobiles) and can potentially have the ability to meet the requirements of safety glass, Depending on the materials used, their dimensions, the number of layers, etc. The layer (s) of vibration damping material must be thick enough to provide appropriate damping properties. If the layer (s) of vibration damping material is too thick, clarity problems may arise. A layer (s) of thinner vibration dampening material (s) can provide easier fabrication as a glass construction having a layer (s) of thinner vibration dampening material (s) would be more similar in dimension To the conventional safety glass that can potentially, depending on its properties be used to replace it. When the laminated article of the present invention comes into resonance, the layer (s) of vibration damping material is cut and dissipates the energy as heat instead of noise. The present invention is particularly advantageous since good results can still be obtained by using a relatively thin layer (s) of vibration damping material. Thus, the article of the present invention which can potentially, depending on its construction, have safety properties, provides improved properties with respect to vibration damping compared to conventional safety glass with only a negligible increase in thickness. Preferably, the first layer of a flexible plastic positioned between the first rigid layer and the layer (s) of vibration damping material of the article of the invention is of such a nature that a test construction of the first layer of plastic flexible laminated between two sheets of annealed glass, each sheet of annealed glass has a thickness of 2.5 mm, pass it the test of the Consumer Product Safety Commission, 16CFR, Part 1201, Category II; and preferably the second optional layer of flexible plastic positioned between the second rigid layer and the layer (s) of vibration damping material is of such a nature that a test construction of the second layer of flexible plastic laminated between two annealed glass sheets, each sheet of annealed glass has a thickness of 2.5 mm, pass it the test of the Consumer Product Safety Commission 16CFR, Part 1201, Category II. In one embodiment, the article of the invention may be of such a nature that the laminate is transparent. In another embodiment, the article of the invention may be colorless.

In another embodiment, the second layer of flexible plastic is present. In another embodiment of the article of the present invention, the first rigid layer is made of glass and the second rigid layer is made of glass. One layer (s) of preferred vibration damping material (s) is selected from the group consisting of urethane rubbers, silicone rubbers, nitrile rubbers, butyl rubbers, acrylic rubbers, natural rubbers, styrene-butadiene rubbers, polyesters, polyurethanes, polyamides, ethylene-vinyl acetate copolymers and inter-penetrating epoxy-acrylate networks. Each layer of vibration damping material may optionally comprise a combination of vibration damping materials. When more than one layer of the vibration damping material is present, each layer may optionally comprise a different vibration damping material. The article of the present invention has a variety of uses. The article of the invention can for example be selected from the group consisting of glasses for land vehicles, architectural glasses, aircraft glasses, and ship glasses. The article of the invention can thus be used as a window for a vehicle or structure. For example, the article of the invention may be a windshield. The present invention also provides a vehicle having at least one article of the present invention (a windscreen for example), equipped therein. The present invention also provides a structure (such as a construction) having at least one article of the present invention equipped thereon. In another embodiment of the article of the present invention at least one of the layer (s) of vibration damping material is resistant to the plasticizer. The article of the invention may optionally further comprise a flexible plastic layer which is resistant to the plasticizer between the layer (s) of vibration damping material and the first flexible plastic layer, such as polyvinyl butyral layer and optionally a second layer. flexible plastic layer that is resistant to the plasticizer between the layer (s) of vibration damping material and the second layer of flexible plastic (such as a layer of polyvinyl butyral), if the second layer of flexible plastic is present. In another embodiment of the article of the invention, the article further comprises a first layer of plastic resistant to the plasticizer, between the layer (s) of the vibration damping material and the first layer of flexible plastic and optionally a second layer of plastic plasticizer resistant between the layer (s) of vibration damping material and the second layer of flexible plastic, if the second layer of flexible plastic is present. In another embodiment, the article of the invention is of such a nature as to pass it the test of the Consumer Product Safety Commission 16CFR, Part 1201, Category I (described later herein). In another embodiment, the article of the invention is of such a nature that it passes the test of the Consumer Product Safety Commission 16CFR 1201, Category II.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 illustrates a side view of one embodiment of the article of the invention. Figure 2 illustrates a side view of another embodiment of the article of the invention. Figure 3 illustrates a side view of a known article. Figure 4 is a graph illustrating the results of the Forced Vibration Tests for Example 2 and Comparative Example 1. Figure 5 is a graph illustrating the results of the Acoustic Tests for Example 2 and Comparative Example 1.

Detailed Description of the Invention Rigid Layers Examples of appropriate rigid layers are those selected consisting of glass and plastic. Rigid layers are usually of the same material (both glass or both plastic, for example). Optionally, the rigid layers can be made of different materials. Examples of suitable rigid plastics include, but are not limited to, those selected from the group consisting of polycarbonate, polystyrene, polyacrylate, polymethylmethacrylate and polyvinylchloride. Examples of suitable glasses include but are not limited to lacquered glass, float glass, window glass, tempered glass, annealed glass and Pyrex ™ glass (a borosilicate glass). Preferably, the rigid layer is made of glass for reasons of optical clarity, resistance to aging (yellowing and degradation), and resistance to organic solvents. The glass used is normally annealed glass. A suitable rigid layer usually has a tensile modulus of at least about 10 × 10 dynes / cm 2, preferably at least about 10 × 10 dynes / cm 2, and more preferably at least about 5 × 1 × 11 dynes / cm 2. Useful rigid materials are normally transparent and colorless, although in some applications they can optionally be dyed. Also for some applications, the rigid layers may optionally be translucent or opaque.

Material Vibration Damper The vibration dampening material (VDM) can include any material that is viscoelastic. A viscoelastic material is one that is viscous and therefore capable of dissipating energy and still exhibits certain elastic properties and therefore has the ability to store energy at the desired temperature and frequency range. That is, a viscoelastic material is an elastomeric material that normally contains long chain molecules that can convert mechanical energy into heat when they are deformed. Such a material can be commonly deformed, for example, stretched by an applied load and gradually gains its original shape again, for example, contracting some time after the load has been removed. Viscoelastic materials suitable for use in vibration damping materials according to the present invention have a storage modulus, that is, measured from the energy stored during deformation of at least about 6.9? - Pascais (1 pound / inch2) at the operating frequency temperature (commonly about -40 to 150 ° C and about 1 to 10,000 Hz). The storage module of the useful viscoelastic materials can be as high as 3.45 x 109 Pascais (50,000 pounds / inches2); however, it is usually around 6.9 x 104 to about 1.4 x 107 Pascais (10 to about 2000 pounds / inches2). Particularly preferred viscoelastic materials provide the cushioned laminate article with a voltage energy ratio, that is, a fraction of the voltage energy stored in the damper material in relation to the total voltage energy stored in the structure, of at least about 2%. Appropriate viscoelastic materials, at the temperature and frequency of operation, for use in vibration damping materials, have a loss factor, that is, the ratio of energy lost to stored energy of at least about 0.01. Preferably, the loss factor is at least about 0.1, more preferably about 0.5 to about 10, and more preferably about 1 to about 10, at the frequency and temperature of operation experienced by the material. This loss factor represents a measure of the energy dissipation of the material and depends on the frequency and temperature experienced by the damper material. For example, for a certain cross-linked acrylic polymer (3M ISD 112 Viscoelastic Damping Polymer acrylic vibration damping material, commercially available from Minnesota Mining and Manufacturing Company, St. Paul, Minnesota, at a frequency of 100 Hz, the loss at a temperature of 20 ° C (68 ° F) is about 1.0, while at a temperature of 70 ° C (158 ° F) the loss factor is about 0.7.The preferred viscoelastic materials are those that remain functional in a wide range of temperatures, for example, -40 ° C to 149 ° C (-40 ° F to 300 ° F) .The most preferred viscoelastic materials are those that cover the widest temperature and frequency range at the smallest factor of desired loss and storage modulus to obtain the acceptable cushioning of the cushioned laminate article and that does not undergo significant degradation in properties due to long exposures to high temperatures or short exposures beyond these high temperature levels. Useful viscoelastic shock absorbing materials can be isotropic materials also as anisotropic materials, particularly with respect to their elastic properties. As used herein, an "anisotropic material" or "non-isotropic material" is one in which the properties are dependent on the direction of the measurement. Appropriate viscoelastic materials are included, but are not limited to, those selected from the group consisting of urethane rubbers, silicone rubbers, nitrile rubbers, butyl rubbers, acrylic rubbers, natural rubbers, mixtures thereof and the like. Other viscoelastic vibration damping materials useful include polyester, polyurethane, polyamides, ethylene-vinyl acetate copolymers, interpenetrating epoxy-acrylate networks and the like. Specific examples of useful materials are described or referenced therein in U.S. Patent No. 5,183,863 issued to Nakamura et al., (February 2, 1993), U.S. Patent No. 5,262,232 issued to Wilfong et al., ( November 16, 1993), and U.S. Patent No. 5,308,887 issued to Ko et al., (May 3, 1994). Examples of thermoplastic materials suitable for use as the vibration damping material in cushioned laminated articles according to the present invention include, but are not limited to those selected from the group consisting of polyacrylates, polycarbonates, polyetherimides, polyethers, polysulfones, polystyrenes , block copolymers of acrylonitrile-butadiene-styrene, polypropylenes, acetal polymers, polyvinylacetyl polymers, polyamides, polyvinyl chlorides, polyethylenes, polyurethanes and combinations thereof. Useful viscoelastic materials can also be crosslinkable to improve their strength and processability. Such viscoelastics are classified as thermosetting resins. When the viscoelastic material is a thermosetting resin, then before the manufacture of the cushioned laminate article, the thermosetting resin is in a thermoplastic state. During the manufacturing process, the thermosetting resin can be further cured and / or crosslinked to a solid state, although it could be a gel after curing. Preferably, the cured material possesses the viscoelastic properties described above. Depending on the particular thermosetting resin employed, the thermosetting resin may include a curing agent, for example, catalyst, which when exposed to an appropriate source of energy (such as thermal energy) initiates the polymerization of the thermosetting resin. Particularly preferred viscoelastic cushioning materials are those based on acrylates. In general, any suitable viscoelastic material can be used. The selection of an appropriate cushioning material is also based on the processability of the cushioning material in a cushioned laminate article and the desired structural integrity of the construction of the finished article with the selected cushioning material. It will be understood that mixtures of any of the above materials can also be used. The preferred vibration damping layer (s) are selected from the group consisting of polyacrylate for reasons of optical clarity, aging resistance, and excellent damping characteristics, for example, a crosslinked acrylate having a vitreous transition temperature (Tg) between 0 ° C and 50 ° C measured at a frequency of 10 Hz and a loss factor of at least approximately 0.5 when measuring a frequency greater than or equal to 10 Hertz of 10 ° C at 40 ° C.

Flexible Plastic Layer The flexible plastic sheet (s) or layer (s) included in the article of the invention typically consist of a thermoplastic material such as polyvinyl butyral (PVB). The PVB is commonly used as a layer because it has a high modulus of tension, exhibits a considerable elongation at breaking and because it is an efficient energy absorber. Therefore, it is effective to withstand certain impacts. At the same time, PVB has a relatively high adhesion to glass. Therefore, if the glass splinters as a result of impact or breakage of the glass, the broken glass has the tendency to be retained by the PVB. Another potentially useful flexible film is the lamination of adhesive films and polyvinyl chloride described in U.S. Patent No. 5,352,528. At least one layer of a flexible plastic material such as polyvinyl butyral (PVB), which is a reinforcing plastic material, is present in the article of the invention. In some cases, two or more layers of flexible plastic material, such as PVB may be present. The polyvinyl butyral is advantageous due to its weather resistance and tendency not to discolour. The polyvinyl butyral is also advantageous due to its colorless nature, transparency, high degree of flexibility and strength. Other films with equivalent features would most likely be useful as a substitute for these films and it is proposed that they be covered in the present.

Construction of the Article The thickness of the individual layers present in the laminate can vary in addition to the proportions of the thickness of the various layers to the other layers. Each stiff layer commonly has a thickness of about 1 to about 7 mm, preferably about 2 to about 5 mm and more preferably about 2 to about 4 mm. A thick rigid layer is desirable due to its superior properties as an acoustic and resistance barrier. However, the aggregate mass may be undesirable in a particular application. A thin rigid layer is not as good as an acoustic barrier and can also sacrifice resistance for a particular application. The layer (s) of vibration damping material typically has a total thickness of about 0.01 mm to about 0.8 mm, preferably about 0.025 raí to about 0.25 mm and more preferably about 0.025 mm to about 0.13 mm , for reasons of performance and optimized cushioning and manufacturing. If the total thickness of the layer (s) of cushioning material of the invention is greater than about 0.8 mm, the additional mass may be undesirable from a consideration of overall weight. Also, an increase in thickness can potentially reduce optical clarity. further, a layer (s) of vibration damping material having a greater overall thickness may not be as efficient as a damper due to the reduced stress. If the total thickness of the layer (s) of vibration damping material is less than about 0.01 mm, less acoustic loss can result. Also, adhesion to rough glass or plastic surfaces is more difficult with a very thin layer (s) of vibration damping material. Each flexible plastic layer, such as a layer of PVB, typically has a thickness of from about 0.1 mm to about 1.5 mm, preferably from about 0.2 to about 1.0 mm, and more preferably from about 0.3 to about 0.8 mm. If such a flexible plastic layer such as a layer of PVB is thicker than about 1.5 mm, it becomes more likely that the imperfections or overall reduction in clarity (nebulosity) are present and the overall laminate becomes too thick to be used in conventional manufacturing processes. In addition, a thicker flexible plastic layer may be undesirable from a consideration of overall weight. If a flexible plastic layer, such as a layer of PVB, is too thin, the layer may not have sufficient structural or cohesion resistance to provide appropriate safety properties. However, it is important to note that the exact thickness of a flexible plastic layer, such as a layer of PVB required, must be determined by those skilled in the art of manufacturing safety glasses. It is not possible to list in the present, the exact dimensions and the composition of the article and the individual layers for a particular safety glass application. Care must be taken to ensure that laminate is prepared by and tested by those of ordinary experience in the safety glass manufacturing technique, before use in applications where the performance of safety glass type is desired. The ratio of the total thickness of the layer (s) of the vibration damping material to the thickness of a rigid layer normally fluctuates around 1: 200 (one (or more) layer (s) of vibration damping material). thin? about 1: 2 (one layer (s) of the very thick vibration buffer material), preferably 1: 100 to about 1:10, and more preferably 1: 100 to about 1:40 for reasons of damping performance, optical clarity, a good level of stiffness, weight considerations and ease of fabrication.Preferably, the layer (s) of the vibration damping material has (adhesive) properties, however, an adhesive Separate can be used to assist in the adhesion of the layer (s) of vibration damping material to a rigid layer The ratio the total thickness of the layer (s) of vibration damping material, to a flexible plastic layer such as a layer of PVB fluctuates normally about 1: 100 to about 10: 1, preferably about 1:50 to about 1: 1, and more preferably about 1:20 to about 1: 2. The thickness of the flexible plastic layer such as a PVB layer (s) is determined in part by the desired security properties. It is desirable that the total thickness of the layer (s) of vibration damping material be large enough to provide adequate cushioning, but thin enough for the proposed processing and use of the laminated article. The ratio of the thickness of a rigid layer to a flexible plastic layer, such as a layer of PVB, typically ranges from about 200: 1 to about 1: 1, preferably about 100: 1 to about 2: 1, more preferably about 10: 1 to about 3: 1 for optimum optical clarity, stiffness and weight.

Cushioning Properties The laminate article of the present invention will have a higher composite loss factor at the temperature and frequency of use (e.g., -10 to 50 ° C and 20 to 2000 Hz) than a monolithic sheet of the rigid layer that have the same thickness, assuming that a type of rigid layer is used. If more than one type of rigid layer is used, this would be true for any of the rigid layers. A specific temperature and frequency, which could be measured is 20 ° C and 100 Hz, for example. This results in lower levels of structural vibration in the laminate. This results in widely diminished levels of noise transported by the structure and also decreased levels of noise transported by air especially in the frequency range where the coincidence occurs. The "composite loss factor" can be measured by using an excitation source in conjunction with an accelerometer. The signal of each is input to a Fast Fourier Transform Analyzer (FFT) which results in a transfer function. The composite loss factor is calculated by using the Medium Power Bandwidth Method. A frequency response spectrum of the transfer function of the FFT analyzer is obtained. There is a peak or maximum in the curve at each modal resonance. The loss factor is determined by advancing the curve on both sides of the peak until the transfer function is half the value of the peak. The frequency difference between the two points of the power half divided by the frequency at which the peak is presented, is the loss factor, that is, the width (Hz) of the resonant peak at 3 db less than the amplitude of the peak divided by the resonant frequency (Hz) at the amplitude of the peak.

Characteristics of the article The articles of the invention and the individual layers from which they are formed are normally colorless and transparent. However, the article and / or one or more individual layers may optionally be dyed or may have private coatings. The damping properties of the article of the invention result in a reduction of resonant frequency peaks. The article of the invention and / or one or more of the individual layers may optionally be translucent and / or opaque.

Layers / Optional Components Optionally, a layer (s) of plastic resistant to the plasticizer in the laminate can be provided. An example of such a plasticizer-resistant polyester layer is polyester (PET). The plastic layer resistant to plasticizer would normally be a tensile modulus of 1 x 10 9 to 1 x 10 11 dynes / cm 2 in addition to being resistant to the plasticizer which may be present in the flexible plastic layer such as PVB. Such plastic layer resistant to plasticizer would normally be thin and flexible. It would normally have a thickness from about 0.01 mm to about 0.8 mm, preferably from about 0.025 mm to about 0.02 mm, more preferably about 0.025 mm to about 0.13 mm, and more preferably about 0.025 mm. In general, it would be colorless, although it can optionally be dyed or have a coating of privacy on it. In general, it would be transparent, although it may be optionally translucent or opaque. Examples of other suitable plasticizer-resistant plastic boxes include, but are not limited to the following: polypropylene, polyimide, urethane or vinyl chloride-vinyl acetate copolymers, such as are described in U.S. Patent No. 4,605,592; issued to Paquette et al., and the like. Such plastic layer resistant to plasticizer would normally be positioned between a layer of the flexible plastic layer such as PVB and the layer (s) of vibration damping material. Such plastic layer resistant to plasticizer serves to prevent the plasticizer, which may be present in the flexible plastic layer, such as PVB, from migrating to the layer (s) of the vibration damping material. Optionally, a layer (s) of vibration damping material can be used that are resistant to the plasticizer that can be contained in a flexible plastic layer, such as a layer of PVB. Such materials are commercially available from a variety of sources. Examples of such vibration damping material include, but are not limited to the following: a terpolymer of n-butylacrylate, methylacrylate and acrylic acid as described in U.S. Patent No. 4,605,592, issued to Paquette et al. acrylic copolymer mixed with nitrile butadiene rubber as described in U.S. Patent No. 4,943,461 ,. issued to Karim; an acrylic copolymer mixed with ethylene vinyl acetate, as described in U.S. Patent No. 5,079,047, issued to Bogart, et al .; an acrylic copolymer mixed with dioctyl phthalate plasticizer as described in U.S. Patent No. 946,742, issued to KLandin, and U.S. Patent No. 4,985,488. The laminate may optionally further comprise one adhesive layer (s). A layer of adhesive can potentially be used between any two layers of the laminate to bond the two layers together. The adhesive would normally have the following properties: transparency, resistance to aging (yellowing), and resistance to solvents. Examples of such adhesives include epoxies, acrylates, cyanoacrylates, silicones and the like. It is believed that the layers that would allow the laminate to also function as an antenna (conductive traces) or a defroster 'could also be present. The surface modification of certain layers such as the plastic layer (s) resistant to the optional plasticizer, may be possible, such as priming, corona treatments, or flame treatments, to improve the bonding to the (s) layer (s) modify (s).

Constructions Examples of suitable laminate constructions include, but are not limited to the following: glass / layer of vibration damping material / PVB / glass; glass / PVB / PET / layer of vibration dampening material / PET / PVB / glass; glass / layer of vibration absorbing material / PET / PVB / glass; and glass / PVB / layer of vibration dampening material / PVB / glass. Rigid plastic can be used instead of one or more layers of glass in the previous constructions.

In addition, other flexible plastic layers such as those discussed above, can be used in place of PVB. In addition, other layers of plastic resistant to the plasticizer can be used such as those previously discussed in place of PET. The vibration damping material as an inner layer (s) in the laminated article serves to dissipate the energy of vibration into heat energy, due to the cut that is initiated in the damping material of the vibration. The present invention will be better understood by reference to the following figures 1-5. Figure 1 illustrates a side view of an embodiment of article 2 of the invention. Figure 1 is a construction of the following: glass / PVB / layer of vibration damping material / PVB / glass. An inner layer of vibration absorbing material 8 is laminated between the two layers of PVB, each identified as 6. On the side of each layer 6 of PVB, opposite to layer 8 of vibration damping material, there is a glass layer 4 to which a layer 6 of PVB is glued. Figure 2 illustrates a side view of another embodiment of the article 10 of the invention. Figure 2 is a construction of the following: glass / PVB / layer of vibration damping material / glass. An inner layer of the layer 16 of vibration damping material is laminated to a layer of PVB identified as 14. On the side of the layer 14 of PVB opposite the layer 16 of vibration damping material is a glass layer 12 to which layer 14 of PVB is stuck. On the side of the layer 16 of vibration damping material, opposite the layer 14 of PVB, there is another glass sheet 12 to which the layer 16 of vibration damping material is stuck. Figure 3 illustrates a side view of an article of prior art 18 having a layer of PVB 22 laminated between two layers of glass 20.

USES OF THE ARTICLE OF THE INVENTION The article of the invention can be equipped in a variety of other articles such as vehicles, structures, etc. The article of the invention can be used as follows: glasses for terrestrial vehicles, such as side glass of automobile, rear glass of automobile and windshield of automobiles, etc.; glasses for aircraft, such as aircraft windshields, aircraft side windows and aircraft rear windows; glasses for boats such as windshields of boats, side glasses of boats and later glasses of boats; architectural glasses such as building windows, such as office construction windows, residential windows, airport windows, etc .; glasses, peepholes; aquariums; etc. The present invention also provides buildings; ships (vehicles), such as land vehicles, watercraft and air craft; glasses; peepholes, etc .; containing the laminated article (s) of the invention.

Manufacturing Method of the Invention Article The laminated article of the invention can be made by a variety of different methods. As an example, one layer (s) of cushioning material of the invention when in the form of a film can be laminated between two sheets of flexible plastic such as PVB sheets or laminated directly on a sheet. Flexible plastic sheet, such as a PVB sheet. However, one or more layers (s) of vibration damping material could also be coated with a solution directly on a flexible plastic sheet such as a PVB sheet to form an intermediate laminate. When the coated flexible plastic sheet (such as a PVB sheet) is heated, the solvent is evaporated to produce a layer of vibration damping material, solid to which a second sheet of flexible plastic (such as a PVB sheet) can be laminated if desired. Alternatively, the vibration dampening material (s) can be directly coated by means of a nozzle on a flexible plastic sheet (such as a PVB sheet). Alternatively, the vibration dampening material (s) can be coated directly by means of a mold on a flexible plastic sheet (such as a PVB sheet). A plasticizer resistant sheet, (such as a PET sheet) can optionally be laminated between the layer of the vibration damping material and the flexible plastic material, such as PVB by a variety of methods in which they are included, but not they are limited to the use of heat and / or pressure, and / or an adhesive. Then, the stiff glass or rigid plastic layers may be attached to either side of the intermediate laminate by a variety of methods which include, but are not limited to the use of heat and / or pressure and / or an adhesive Alternatively, the sequential extortion of the material composing the flexible plastic sheet, such as PVB and a vibration damping material on a layer of plastic or rigid glass may be presented followed by the application of another layer of rigid glass or plastic on top of the sheet. Other methods of preparation would also be possible.

PROOF OF THE CONSUMER PRODUCTS SECURITY COMMISSION (CPSC) 16CFR, Part 1201. The test material, (such as a test construction) to be tested is placed on a test frame with the test material oriented vertically. A bag filled with 45.36 kg (100 pounds) of lead shot is suspended from a string and swung to make an impact with the test material. Category I materials are tested by dropping the bag from a vertical height of 45.72 cm (18 inches) above the point of impact with a resulting impact of 20.74 kg-m (150 ft-lb). Category I materials can be used in areas of 0.84 m2 (9 square feet) and smaller. Category II materials can be used in areas greater than 0.84 m2 (9 square feet) and are tested by releasing the bag from a vertical height of 1.22 meters (4 feet) above the point of impact with a resulting impact of 55.30 kg. -m (400 ft-lbs). One of three conditions must be met for the test material to pass this test. The test material does not break; or the test material breaks on impact to create an opening through which a 7.62 cm (3 inch) sphere can not pass; or the test material splinters, but the resulting ten largest pieces weigh no more than 64.52 cm2 (10 square inches) of the original test material.

EXAMPLES The following examples further illustrate, but do not limit the present invention. All parts, percentages, proportions, etc., in the examples and any part herein are by weight unless otherwise indicated.

Comparative Example 1 A 610 mm x 610 mm x 0.762 mm film of polyvinyl butyral, commercially available from Monsanto, was laminated at a temperature of 110 ° C to 6.0 x 105 dynes / cm2 for 10 minutes between two sheets of 610 mm x 610 mm x 2.31 mm of floating glass available from Glass Service Co., St. Paul, Minnesota, USA.

Example 2 A construction of a 610 mm x 610 mm by 0.051 mm film of acrylic vibration damping material (Viscoelastic Damping Polymer, trademark 3M ISD 112, commercially available from Minnesota Mining and Manufacturing Company, St. Paul, Minnesota, USA) and of two films of 610 mm x 610 mm x 0.381 mm polyvinyl butyral was prepared using manual pressure. Then, this construction was laminated under the same conditions as Comparative Example 1 between two sheets of 610 mm x 610 mm x 2.31 mm of float glass available from Lass Service Co., St. Paul, Minnesota, USA.

Comparative Example 3 Two sheets of 610 mm x 610 mm x 2.31 mm of float glass available from Glass Service Co., St. Paul, Minnesota, USA were placed together.

Resonant Vibration Test The articles formed according to Comparative Example 1, Example 2 and Comparative Example 3 were tested using a Scanning Laser Doppler Vibrometer (from Polytec Pl) PSV-200. Each item was held horizontally by placing a 25mm x 25mm x 12mm vinyl foam under each of the four corners. The introduction of force was provided by an impact hammer. The response was measured by the Doppler Vibrometer Laser (LDV) at a point immediately adjacent to the excitation point. The LDV converts its instantaneous velocity along the line of sight of the beam to a corresponding velocity signal. Both input and output signals were transferred to a Tektronix 2630 FFT analyzer available from the Tektronix Company, which instantly indicated the transfer function. The loss factor of each of the items for modes 6, 11 and 26 was determined by using the medium-power bandwidth method. Modes 6, 11 and 26 were selected because they were well separated from the other modes. The results are reported in Table I below. Table I Loss Factor Mode Loss Factor, Loss Factor. . Comparative Example 1 Example 2 Comparative Example 3 6 0.0207 0.1818 0.0029 11 0.0644 0.1500 0.0024 26 0.0181 - * 0.0765 0.0020 Forced Vibration Test Comparative Example 1 and Example 2 were tested on an RSA II rheometer from Rheometrics using a 3-point bending geometry. The sample size was 51 mm x 12.5 mm. A scan or sweep of frequency from 0.1 to 100 radians / second with 5 measurements taken in each decade of frequency was performed at each of four temperatures: 0, 10, 20, 30 ° C. The loss factor was measured at each frequency. The principle of time-temperature superposition was then used to create a main curve of the loss factor against the frequency at a reference temperature of 20 ° C. The results are shown in Figure 4. The addition of the viscoelastic shock absorber polymer vibration buffer layer in Example 2 increased the amount of cushioning of the laminate in the frequency range of most concern 20, at 10,000 Hz.

Acoustic Tests The transmission loss for Comparative Example 1 and Example 2 was measured according to the Society of Automotive Engineers (SAE) J1400 entitled "Laboratory Measurements of the Airborne Noise Reduction of Acoustical Materials", May 1989. This test uses a source of white noise in a reverberating salt and a microphone to measure the amount of noise that is able to pass through the glass laminate and into an anechoic chamber. The results are shown in Figure 5. From Figure 5 it can be seen that the addition of the vibration damping material to the laminate increases the transmission loss at low frequencies (100 Hz to 400 Hz) and high frequencies (1000 Hz to 10,000). Hz) where the matching resonance starts.

Various modifications and alterations of this invention will become apparent to those skilled in the art without departing from the scope and spirit of the scope of this invention and it should be understood that this invention is not unduly limited to the illustrative embodiments illustrated herein. It is noted that, in relation to this date, the best method by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates.

Claims (10)

1. Claims Having described the invention as above, the content of the following claims is claimed as property: 1. An article comprising a laminate, characterized in that the laminate comprises: (a) a first rigid layer formed from a material selected from the group consisting of glass and plastic; (b) a second rigid layer formed of a material selected from the group consisting of glass and plastic; (c) a layer (s) of vibration damping material positioned between the first rigid layer and the second rigid layer; (d) a first layer of a flexible plastic, positioned between the first rigid layer and the layer (s) of vibration damping material, wherein the first flexible plastic layer is of such a nature that a test construction from the flexible plastic layer laminated between two sheets of annealed glass, each sheet of annealed glass has a thickness of 2.5 mm, would pass the test of the Consumer Product Safety Commission 16CFR, Part 1201, Category I; and (e) optionally a second flexible plastic layer positioned between the second rigid layer and the layer (s) of the cushioning material of the invention wherein the second flexible plastic layer is of such a nature that a test construction of the second flexible plastic plate laminated between two sheets of annealed glass, each glass sheet has a thickness of 2.5 mm, pass it the test of the Consumer Product Safety Commission 16CFR, Part 1201, Category I. 2. The article of according to claim 1, characterized in that the first layer of a flexible plastic positioned between the first rigid layer and the layer (s) of vibration damping material is of such a nature that a test construction of the first layer of flexible plastic laminated between two sheets of annealed glass, each sheet of glass having a thickness of 2.5 mm, pass it the test of the Consumer Product Safety Commission 16CFR, Part e 1201, Category II; and wherein the second optional layer of flexible plastic positioned between the second rigid layer and the layer (s) of the vibration damping material is of such a nature that a test construction of the second layer of flexible plastic laminated between two sheets of annealed glass, each sheet of glass has a thickness of between
2. 2.5 mm, would pass the test of the Consumer Product Safety Commission, 16CFR, Part 1201, Category II.
3. 3. The article according to claim 1, characterized in that the second flexible plastic layer is present.
4. 4. The article according to claim 1, characterized in that the first rigid layer is made of glass and the second rigid layer is made of glass.
5. 5. The article according to claim 1, characterized in that the layer (s) of the vibration damping material is selected from the group consisting of urethane rubber, silicone rubber, nitrile rubber. , butyl rubbers, acrylic rubbers, natural rubbers, styrene-butadiene rubbers, polyesters, polyurethanes, polyamides, ethylene-vinyl acetate copolymers and epoxy-acrylate interpenetrating networks.
6. 6. The article according to claim 1, characterized in that the article is a window for a vehicle or a structure. The article according to claim 1, characterized in that at least one of the layers of vibration damping material is resistant to the plasticizer. 8. The article according to claim 1, characterized in that it further comprises a plastic layer resistant to the plasticizer between the layer (s) of vibration damping material and the first layer of flexible plastic and optionally a second layer. Plasticizer resistant plastic between the layer (s) of the vibration damping material and the second layer of flexible plastic, if the second layer of flexible plastic is present. 9. The article according to claim 1, characterized in that the first flexible plastic layer is polyvinyl butyral. 10. A vehicle or construction characterized in that it has at least one article in accordance with claim 1, equipped therewith.