JPH0144732B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a glass-polyurethane laminate sheet and a polyurethane sheet suitable therefor, and particularly to a glass-polyurethane laminate sheet with an exposed polyurethane surface and a polyurethane sheet suitable therefor. A laminated sheet of a glass sheet and a synthetic resin sheet is well known as safety glass. For example, a laminated sheet having a three-layer structure of glass, polyvinyl butyral, and glass is widely used as safety glass for automobiles. The synthetic resin layer laminated between such glass sheets is called an interlayer film.
Polyvinyl butyral, polyurethane, and various other synthetic resins have been used or proposed. On the other hand, in a laminated sheet made of glass and synthetic resin, one side is glass and the other side is synthetic resin, such as a laminated sheet with an exposed synthetic resin layer, such as glass-synthetic resin or glass-synthetic resin-glass-synthetic resin. Laminated sheets are attracting attention for applications such as automotive safety glass. This laminated sheet is considered to be even safer than conventional laminated sheets with glass on both sides. For example, if this laminated sheet is used as a car windshield with the synthetic resin side facing the inside of the car, there will be fewer lacerations and cuts when a driver etc. collides with the windshield, and even if the glass breaks, the car will not be damaged. It is also believed that there will be less glass shards flying inside. Such a laminated sheet in which one side is glass and the other side is synthetic resin is hereinafter referred to as "bilayer glass", and a laminated sheet in which both sides are glass using an interlayer film is hereinafter referred to as "laminated glass". Bilayer glass is described, for example, in JP-A-48-41423, JP-A-48-25714, JP-A-49-34910, and JP-A-53-27671. As can be seen from these known examples, the exposed synthetic resin layer (hereinafter referred to as bilayer layer) is usually composed of polyurethane. Polyurethanes are also well known as interlayers in laminated glass. Polyurethanes include so-called thermoplastic polyurethanes and thermosetting polyurethanes; the former is a linear polymer and is usually obtained by reacting a high molecular weight diol, a chain extender, and a diisocyanate compound, and the latter is a crosslinked polymer. ,
For example, it can be obtained by reacting a high molecular weight diol, a crosslinking agent, and a diisocyanate compound. The bilayer layer needs to be strongly bonded to the glass. However, when thermosetting polyurethane is used as a bilayer layer, there is a problem that it does not adhere firmly to glass. On the other hand, thermoplastic polyurethane adheres strongly to glass, but as long as it is used as a bilayer layer, the other side will be exposed, so the nature of its surface becomes a problem. That is, thermoplastic polyurethane has insufficient weather resistance and is easily attacked by solvents. These problems are explained in detail in the above-mentioned Japanese Patent Application Laid-Open No. 53-27671, particularly on pages 6 to 7. In order to solve the above problems, the invention described in JP-A No. 53-27671 consists of a bilayer layer made of two polyurethane layers, with the surface made of thermosetting polyurethane and the adhesive surface to glass made of thermoplastic polyurethane. By doing so, we are trying to solve the problem. Since both polyurethanes adhere strongly, this invention solves the problems of adhesion and surface properties of the bilayer layer to the glass. However, it is not considered that all problems have been completely solved by this invention. For example, the invention requires the production of sheets of two different polyurethanes (referred to as preformed sheets), which requires a relatively complex process. For example, as explained in page 10, lower right column, line 13 to page 11, upper right column, line 14, one sheet may be poured onto the other to integrate it, or one sheet may be dissolved in a solvent. This requires a method such as applying it to the other surface. The inventors of the present invention have conducted various research studies in order to find a polyurethane sheet that solves the problems of adhesion with glass and surface properties, and also solves the problems in manufacturing or processing the polyurethane sheet. As a result, we have discovered a specific polyurethane sheet that has both thermoplastic and thermosetting properties and can be called a semi-thermoplastic polyurethane sheet or a semi-thermosetting polyurethane sheet. This polyurethane sheet not only has excellent adhesion to glass and its surface properties, but also solves the above manufacturing and processing problems because it is a single layer sheet. The present invention relates to this specific polyurethane sheet and a glass-polyurethane laminate sheet using the same. That is, the present invention has an average molecular weight of 1000 to 5000 and an average number of functional groups (f).
Thickness obtained by reacting at least three components: a mixture of a high molecular weight diol with 2.1≦f≦3.5 and a trifunctional or higher functional high molecular weight polyol, a chain extender and/or crosslinking agent, and a polyisocyanate compound.
It is a polyurethane sheet for lamination with a thickness of 0.1 to 5.0 mm.
Furthermore, it is a laminate made by laminating a glass or plastic sheet on one side of the sheet. First, the polyurethane sheet will be explained. As mentioned above, the polyurethane sheet of the present invention has properties intermediate between thermoplasticity and thermosetting. Therefore, not only can it be directly and firmly adhered to glass, but its surface solvent resistance is significantly superior to that of thermoplastic polyurethane, and is almost equivalent to that of thermosetting polyurethane. This polyurethane can be formed into a sheet by a method similar to thermosetting polyurethane, such as casting. The polyurethane sheet of the present invention can be directly laminated and integrated with a glass sheet by heating and pressing. Therefore, a smoother bilayer layer can be formed compared to a method in which a polyurethane layer is formed by casting on a glass sheet. The polyurethane sheet is preferably a polyurethane sheet that has not yet been completely cured. By curing the polyurethane sheet, which has not yet been completely cured, in a state where it is laminated with a glass sheet, etc., the adhesive strength of the glass sheet, etc. can be further improved. Polyurethane which has not yet been completely cured is known, for example, from Japanese Patent Publication No. 47-5556. In general, thermosetting resins such as thermosetting polyurethane have A
It can be divided into stage, B stage and C stage. Stage A refers to a state in which the resin is a viscous liquid, and stage C refers to a state in which the reaction has proceeded almost completely. The B stage is an intermediate stage between these stages, and is a solid that appears to be almost completely cured in appearance, but is in a state where it can be fluidized by heating or the like. The polyurethane sheet that has not yet been completely cured is a polyurethane sheet that is in the B stage. This polyurethane sheet, which has not yet been completely cured, can be produced in the same manner as the polyurethane sheet forming process described above. However, it is necessary to form the polyurethane into a sheet so that it does not transition to the C stage, and for this purpose, various conditions may need to be adjusted. These conditions include, for example, selection of the type and amount of raw materials used, adjustment of factors that change the reaction rate, such as catalysts in particular, and adjustment of temperature and time during reaction or sheet formation. Generally, sheets are manufactured under relatively mild conditions while preventing the reaction from proceeding too much.
Further, it is preferable that the obtained sheet is stored at low temperature. By this method, a sheet with a smooth surface and a uniform thickness can be obtained, and by heating and pressurizing the laminated state of this and a glass sheet, etc., a laminate with excellent adhesive strength can be obtained. Another feature of the polyurethane sheet of the present invention is that it is manufactured using a high molecular weight polyol having an average hydroxyl group f of 2.1≦f≦3.5. Considering the case where no crosslinking agent is used, when f of the high molecular weight polyol is 2, a thermoplastic polyurethane is usually obtained, and as the value of f becomes higher than 2, the thermosetting property becomes stronger. If f exceeds 3.5, the thermosetting properties will be too strong and the adhesiveness to the glass sheet will be insufficient, making it impossible to directly laminate the polyurethane sheet to the glass sheet. The use of crosslinking agents enhances the thermosetting properties of polyurethane; therefore, the use of crosslinking agents increases the f of high molecular weight polyols.
2.1 or close to it can be used. In the present invention, a chain extender is usually essential, and when f of the high molecular weight polyol is 2.1 or close to it, a chain extender and a crosslinking agent are used together or a crosslinking agent is used in place of the chain extender. It is desirable that In the present invention, the concept of inter-branch point molecular weight is introduced to represent the properties intermediate between thermoplasticity and thermosetting of polyurethane. High molecular weight polyols include high molecular weight polyols having at least three hydroxyl groups. Therefore, it is considered that this high molecular weight polyol crosslinks the molecular chains of polyurethane.
Thermoplastic polyurethanes are linear polymers without branch points, and thermosetting polyurethanes are branched and/or network polymers with a large number of branch points. On the other hand, the polyurethane of the present invention differs from thermoplastic polyurethane in that it has branch points, and differs from ordinary thermosetting polyurethane in that it has fewer branch points. The molecular weight between branch points is the average molecular weight between two branch points, and the more branch points there are, the lower this molecular weight will be, and the stronger the properties of thermosetting polyurethane will be. The higher the molecular weight, the stronger the properties of thermoplastic polyurethane. The molecular weight between branch points of a thermoplastic polyurethane is considered to be essentially infinite, and the molecular weight between branch points of a known thermosetting polyurethane forming a bilayer layer is at most 2,700. This inter-branch point molecular weight is a value obtained by dividing the total reactive raw materials (weight) forming polyurethane per mole of high molecular weight polyol by the number of functional groups. For example, the average number of hydroxyl groups f
When obtained from only three components: a high molecular weight polyol, a chain extender and a diisocyanate compound,
The value obtained by dividing the total weight of these three components per mole of high molecular weight polyol by f becomes the inter-branch point molecular weight. In addition, when using a crosslinking agent,
The value is obtained by dividing the total weight of these four components by the value obtained by adding (number of moles of crosslinking agent per mole of polymer weight) x (average number of functional groups of crosslinking agent) to f. Furthermore, when a trifunctional or more functional polyisocyanate compound is used, the molecular weight between branch points also decreases. In this calculation, the catalyst and non-reactive raw materials (for example, colorants and stabilizers) are excluded from the calculation, and the calculation is essentially made using only the above three to four components. The molecular weight between branch points of the polyurethane in the present invention is preferably 2000 to 2000.
10,000, more preferably 3,000 to 10,000. Polyurethane with a molecular weight between branch points of less than 3,000 has strong thermosetting properties and an uncured polyurethane sheet is relatively easy to cure, so care must be taken when handling it, but if it is 3,000 or more, it is easy to handle. The above-mentioned Japanese Patent Application Laid-Open No. 49-34910 describes a bilayer glass using thermosetting polyurethane. It has been suggested that this thermosetting polyurethane can be made into a sheet and laminated with a glass sheet, etc., but since this thermosetting polyurethane sheet does not adhere directly to glass etc., it requires the intervention of an adhesive substance. (Page 6, top right column, line 13 to bottom left column, line 4). In the embodiments of the present invention, a thermosetting polyurethane liquid that has not been completely cured is casted onto a glass sheet or a polycarbonate sheet to form a laminated sheet. However, especially in the case of lamination with glass, it is thought that even with this method, the adhesive strength of thermosetting polyurethane is low and a fully satisfactory laminated sheet cannot be obtained. Further, according to the example, the molecular weight between the branch points of this thermosetting polyurethane is as high as 2700.
It does not have the partial thermoplasticity that is the object of the present invention. On the other hand, as mentioned above, JP-A-53-27671 discloses that the adhesive strength between thermosetting polyurethane and glass sheet is extremely insufficient. For this reason, a glass-polyurethane laminate sheet is constructed by interposing a thermoplastic polyurethane between the thermosetting polyurethane and the glass sheet, but this invention has the above-mentioned problems. Furthermore, according to the examples, the thermosetting polyurethane in this invention has an extremely high thermosetting property of 1000 or less, and does not have any partial thermoplasticity, which is the object of the invention. it is conceivable that. In contrast, the polyurethane sheet of the present invention not only has high adhesive strength with the glass sheet but also has high resistance to solvents. Of course, the tear resistance and self-healing properties described in the above-mentioned known examples do not deteriorate, and it is easy to handle, making it extremely suitable as a polyurethane for a bilayer layer in which one side is bonded to a glass sheet. It is believed that there is. Preferably, the polyurethane sheets of the present invention are essentially transparent. For example, even if it is semi-transparent to opaque due to surface irregularities, it may be a transparent laminated sheet as a result of being laminated with a glass sheet by heating and pressing. The polyurethane sheet of the present invention may also be a colored transparent sheet,
Moreover, the coloring may be partial. The polyurethane sheet can be colored by mixing a coloring agent into the raw material, or it can also be mixed with a coloring agent when it is formed into a sheet, or it can be colored after it is formed into a sheet. The polyurethane sheets of the present invention are more transparent than conventional thermoplastic polyurethanes. This is thought to be due to the use of high molecular weight polyols and cross-linking agents, and the more cross-linking to a certain extent, the more transparent the film becomes. Although the thickness of the polyurethane sheet of the present invention is not particularly limited, it is preferably about 0.1 to 5.0 mm in view of its intended use. Various types of mixtures of high molecular weight diols and trifunctional or higher functional high molecular weight polyols can be used in the present invention. Triols and tetraols are preferred as trifunctional or higher-functional high molecular weight polyols. When using a mixture of only high molecular weight diols and high molecular weight triols as this mixed polyol, the average number of functional groups (f) of the mixed polyol is always
It is less than 3.0 and cannot be more than 3. However, if a high molecular weight polyol having four or more functionalities is used instead of the high molecular weight triol or together with the high molecular weight triol, f of the mixed polyol may become 3 or more. The mixed polyol may be a mixed polyol of three or more components. For example, two or more kinds of high molecular weight diols can be used in combination as high molecular weight diols, and two or more kinds of high molecular weight diols can be used in combination as trifunctional or higher functional high molecular weight diols. In the former case, high molecular weight diols having different molecular weights may of course be used in combination, or different types of compounds (for example, polyester diol and polyether diol) may be used in combination. In the latter case, polyols having different numbers of functional groups may be used in combination. Preferred mixed polyols include at least one high molecular weight diol (f=2)
at least one species and a high molecular weight triol (f=3)
It is a mixed polyol containing seeds. Mixed polyols can of course be produced by mixing at least two pre-produced high molecular weight polyols, or by adding epoxide to a pre-mixed initiator mixture of two or more initiators, as in the case of polyether polyols. It is also possible to prepare a mixed polyol. The average molecular weight of this mixed polyol is 1000-5000. When the high molecular weight polyol is a mixture, it may contain one whose average molecular weight is outside this range. However, the high molecular weight polyol referred to herein does not include low molecular weight polyols such as chain extenders and crosslinking agents described later. Types of high molecular weight polyols include, for example, polyether polyols, polyester polyols, polycarbonate polyols, hydrocarbon polymers having two or more hydroxyl groups, and others, but preferred are polyether polyols and polyester polyols. They can be used alone or in combination. It is also possible to use polyether polyol or polyester polyol in combination with other polyols.
The most preferred high molecular weight polyol is a polyester polyol alone or a polyol mixture containing it as a main component. Examples of polyether polyols include those produced by adding a cyclic ether to a homopolymer of a cyclic ether and an initiator. The former mainly yields polyether diols such as poly(oxytetramethylene) glycol, while the latter yields polyether polyols having various numbers of hydroxyl groups depending on the number of active hydrogens in the initiator. The former are polymers of multi-membered cyclic ethers having three or more members, such as poly(oxypolymethylene) glycols such as poly(oxytetramethylene) glycol and poly(oxyhexamethylene) glycol, polyoxyethylene glycol, and oxypropylene glycol,
There are three-membered cyclic ether polymers such as polyoxybutylene glycol. Polyether polyols obtained by adding an epoxide (three-membered cyclic ether) to an initiator have various numbers of functional groups depending on the type of initiator. Polyhydric alcohols are particularly preferred as initiators. Examples of polyhydric alcohols include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, and 1,3-
Propanediol, 1,4-butanediol,
1,3-butanediol, 1,2-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-
Octanediol, 2-butene-1,4-diol, 2-butene-1,4-diol, 2,2-bis(4-hydroxy-cyclohexane)propane, glycerin, trimethylolpropane, trimethylolhexane, pentaerythritol, diglycerin, dextrose, sucrose,
These include diethanolamine, dipropanolamine, and triethanolamine. Initiators other than polyhydric alcohols include amines, polyhydric phenols, and others. These initiators can be used in combination, and initiators with a valence of 5 or more are particularly used in combination with initiators with a valence of 2 or 3. As the epoxide, ethylene oxide, propylene oxide, butylene oxide, epichlorohydrin, other alkylene oxides, as well as styrene oxide, glycidyl ether, glycidyl ester, etc. can be used. Preferred epoxides are alkylene oxides having 4 or less carbon atoms, and it is particularly preferred to use ethylene oxide, propylene oxide, and butylene oxide alone or in combination. When two or more types of epoxides are used together, polyether chains polymerized randomly or in blocks can be obtained. Furthermore, since ethylene oxide provides a primary hydroxyl group, it may be preferable to form an ethylene oxide residue at the end, and since the oxyethylene chain is hydrophilic, it may be preferable to have it present within the polyether chain. The polyester diol is a polyester polyol having a polyhydric alcohol residue and a polybasic acid residue, and is usually obtained from a dihydric alcohol and a dibasic acid or a derivative thereof. A polyester polyol having a functional group number of 3 or more can be obtained by partially using a polyhydric alcohol or a polybasic acid having a valence of 3 or more. Examples of the polyhydric alcohol include the polyhydric alcohols shown above as initiators, especially 2
alcohol is used. As a polybasic acid,
Examples include succinic acid, glutaric acid, adipic acid, sebacic acid, maleic acid, fumaric acid, and terephthalic acid. As derivatives, these anhydrides,
Esters, halides, etc. are used. As other polyester polyols, ring-opened polymers of cyclic esters such as ε-caprolactone can be used. The chain extender in the present invention is a low molecular weight compound having two active hydrogens, and the crosslinking agent is a low molecular weight compound having three or more active hydrogens. Active hydrogen is a hydrogen atom of a hydroxyl group or a hydrogen atom bonded to a nitrogen atom of an amino group, an imino group, or the like.
Particularly preferred chain extenders are dihydric alcohols,
The crosslinking agent is a trivalent or higher polyhydric alcohol. As the polyhydric alcohol that can be used as the chain extender or crosslinking agent, the polyhydric alcohols exemplified as the initiator are preferable. Particularly preferred chain extenders are ethylene glycol and 1,4-
butanediol, and the crosslinking agents are trimethylolpropane and glycerin. Chain extenders or crosslinking agents other than polyhydric alcohols include polyols with a lower molecular weight than the above-mentioned high molecular weight polyols such as low molecular weight polyether polyols and low molecular weight polyester polyols, aromatic diamines,
There are aliphatic diamines and other amines. The molecular weight of the chain extender and crosslinking agent is not particularly limited, but is preferably 300 or less, particularly preferably 200 or less. Various organic polyisocyanate compounds can be used as the polyisocyanate compound. Particularly preferred are diisocyanate compounds, such as aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, and heterocyclic diisocyanates. Preferred diisocyanate compounds are non-yellowing diisocyanate compounds, and aliphatic or alicyclic diisocyanates are particularly preferred. Other diisocyanate compounds can also be used, especially if yellowing is not a problem or if yellowing can be prevented using a stabilizer. Further, the diisocyanate compound may contain a small amount of impurities, or may be a modified isocyanate compound modified by various compounds or treatments. Specifically, for example, tetramethylene diisocyanate, hexamethylene diisocyanate,
Cyclohexylene diisocyanate, bis(4-
Isocyanate cyclohexyl)methane, 2,2
-bis(4-isocyanatecyclohexyl)propane, isophorone diisocyanate, tetrahydronaphthylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, diphenylmethane diisocyanate, xylene diisocyanate, naphthalene diisocyanate, and the like. Particularly preferred is an alicyclic diisocyanate such as bis(4-isocyanatecyclohexyl)methane (also known as hydrogenated MDI) obtained by hydrogenating an aromatic diisocyanate. The polyurethane in the present invention is at least three of the above.
It can be manufactured using various additives in addition to the two essential ingredients. Among the additives, the component usually considered essential is the catalyst. As the catalyst, various amines and organometallic compounds can be used alone or in combination. In addition, antioxidants, ultraviolet absorbers, various other stabilizers, colorants, plasticizers, fillers, or other additives may be used. The reaction ratio of the high molecular weight polyol, chain extender and/or crosslinking agent, and polyisocyanate compound is not particularly limited as long as a good polyurethane sheet can be obtained. However, the polyisocyanate compound usually contains 90 to 120
It is preferred to use equivalents, especially 95 to 110 equivalents.
This number of equivalents is commonly referred to as the isocyanate index. In addition, the proportion of the high molecular weight polyol to the total weight of the high molecular weight polyol and the chain extender and/or crosslinking agent is 75 to 95% by weight, especially 80 to 95% by weight.
92% by weight is preferred. The method for producing polyurethane using the raw materials is not particularly limited. For example, the raw materials can be reacted by a one-shot method, a prepolymer method, a quasi-prepolymer method, or the like. Also, sheeting is
A method of pouring a liquid product made by reacting raw materials into a mold to form a sheet, a method of kneading a prepolymer or quasi-prepolymer with the other raw material to form a sheet, and heating and pressurizing it. Methods of forming sheets by extrusion molding, roll forming, etc.
Alternatively, it can be formed into a sheet by any other suitable method. Casting is carried out on molds with non-stick surfaces. Moreover, it may be pressurized and molded at the same time. The polyurethane sheet thus obtained can be further pressed or heated with a mold or roll having a non-adhesive surface to form a thinner or smoother sheet. The non-adhesive surfaces of molds and rolls for processing polyurethane sheets are preferably made of fluorocarbon resin, polyolefin resin, or other non-adhesive synthetic resin. The polyurethane sheet of the present invention is preferably used for the purpose of producing a transparent laminate by laminating it with a glass sheet, a synthetic resin sheet, or the like. The synthetic resin sheet is preferably a transparent yet strong sheet such as a polycarbonate resin sheet or an acrylic resin sheet. The polyurethane sheet of the present invention can be directly adhered to a glass sheet or these synthetic resin sheets. Of course, depending on the case, an adhesive or an adhesive sheet may be interposed between the two.
Further, at least one of the adhesion surfaces of the two can be chemically or physically treated, such as by being treated with a primer, and then the adhesive can be bonded. In addition, this polyurethane sheet can be placed between two glass sheets as an interlayer film of laminated glass, and can also be placed between a glass sheet and a synthetic resin sheet or between two sheets.
It can also be made to exist between two synthetic resin sheets. Preferably, in order to meet the object of the present invention, the polyurethane sheet is a bilayer layer in which one side is exposed and the other side is a sheet of glass or synthetic resin. A particularly preferred application is when used as a bilayer layer in bilayer glass, one side of which is at least one glass sheet. The present invention also provides a bilayer glass in which the polyurethane sheet is used as a bilayer layer. That is, the present invention provides a polyurethane sheet layer obtained by reacting at least three components: a high molecular weight polyol with an average molecular weight of 1000 to 5000, a chain extender and/or crosslinking agent, and a polyisocyanate compound, and a glass sheet present on one side of the polyurethane sheet layer. A glass-polyurethane laminate comprising at least two layers. The polyurethane sheet layer of the laminate of the present invention is made of the above-mentioned polyurethane. The polyurethane sheet layer is the bilayer layer described above, and one side thereof is preferably exposed. The exposed surface of the polyurethane layer may be a surface subjected to various treatments or a surface to which a thin plastic film is attached. For example, a hard organic layer or an inorganic layer can be formed. However, these treatments are often undesirable because they usually cause the surface of the polyurethane sheet layer to lose its self-healing properties (the ability to automatically heal scratches, etc.), so it is important that the treatments are carried out as long as they do not cause this property to be lost. I like it. The other side of the polyurethane sheet layer is bonded to a glass sheet. An adhesive or the like may be interposed between the polyurethane sheet layer and the glass sheet layer as described above.
However, due to the purpose of the polyurethane, it is preferable that the two be directly contacted and bonded.
The glass sheet layer may be a single layer, or may be a layer consisting of multiple layers of glass like conventional laminated glass. For example, it may be a multilayer glass sheet made of glass-polyvinyl butyral-glass, or it may be composed of at least one relatively thick synthetic resin sheet and at least one glass sheet. . A more preferred laminated sheet of the present invention is composed of one glass sheet layer or a plurality of glass sheet layers having a polyvinyl butyral interlayer and a polyurethane sheet layer present on one side of the glass sheet layer. As the glass of the glass sheet layer in the laminate of the present invention, vehicle glass sheets, aircraft glass sheets, architectural glass sheets, and other glass sheets used for automobiles can be used. Particularly preferred are vehicle glass sheets used for automobile windshields. This glass sheet may be a toughened glass sheet.
Particularly preferred is a tempered glass sheet that is fully or partially strengthened by being rapidly cooled by air cooling. Also preferred are chemically strengthened glass sheets. For example, a glass sheet containing lithium ions is strengthened by ion-exchanging the lithium ions with sodium ions or potassium ions. These glass sheets are described in detail, for example, in the aforementioned Japanese Patent Application Laid-open No. 48-41423, item 6, lower right column, line 3 to page 8, upper left column, line 17. The glass-polyurethane laminate of the present invention can be produced by laminating the polyurethane sheet, particularly a polyurethane sheet that has not yet been completely cured, with a glass sheet, forming the polyurethane into a sheet on the glass sheet and integrating it, or other methods. manufactured by the method. For example, a glass-polyurethane laminate can be directly produced by casting liquid polyurethane onto a glass sheet and then heating and pressurizing it in a mold, without forming the polyurethane into a sheet. A more preferred manufacturing method is a method in which the uncured polyurethane sheet obtained once formed into a sheet is laminated with a glass sheet and then heated and pressed. The glass-polyurethane laminate of the present invention is suitable as a transparent body for vehicles, aircraft, or architecture. A particularly preferred application is for vehicles, and is particularly suitable as a windshield for automobiles. The glass-polyurethane laminate of the present invention is believed to be safer as an automobile windshield than conventional laminated glass. Example 1 411.8 g of polyester polyol (functional group number 2.8) with a hydroxyl value of 61 was heated at 110°C under a vacuum of 2 mmHg.
The mixture was heated for 2 hours for deaeration and dehydration. To this were added 239.6 g of 4,4''-methylene-bis(cyclohexyl isocyanate) and 0.042 g of dibutyltin dilaurate, and the mixture was reacted for 15 minutes at 80°C under a nitrogen stream. Next, 28.1 g of ethylene glycol was added to the reaction mixture.
g and 20.6 g of trimethylolpropane were added thereto, and the mixture was rapidly stirred and mixed. After an exotherm was observed with the start of the reaction and a substantially homogeneous mixture was obtained, the liquid reaction mixture was poured onto a glass plate covered with a release film, and a spacer (0.5 mm thick) was placed.
Furthermore, a release film and a glass plate were placed on top and pressed to obtain a thickness of approximately 0.5 mm. This material was cured by heating for 2 hours in a press at 110°C, and further cured for 8 hours in electricity at 110°C, to obtain a glass-like transparent film. This film was further allowed to stand at 25° C. for one week, and then tested as shown below. The rubbing test was conducted in the presence of mixed alcohol or carbon tetrachloride to test solvent resistance.

[Table] Example 2 The liquid reaction product of Example 1 was sandwiched between a fluororesin-coated plate and heated under electricity at 110°C for 1 hour to obtain a semi-cured film. Two 30cm pieces of this film
x 30cm glass plates, apply release treatment or use a release film on the side of one glass that will be in contact with the film, and if necessary, apply a release film on the side of the other glass that will be in contact with the film. Treat with a silane compound, etc. This silane compound may be used in advance to form a film. Using this non-adhesive glass laminate in an autoclave,
By adhering at 150° C. and 13 atm for 30 minutes and removing the glass, a bilayer, which is a two-layer laminate of glass-plastic film, was created. When this bilayer was subjected to a penetration resistance test with the plastic layer facing up based on the penetration resistance test specified in JIS R3312, the steel balls did not penetrate and the broken glass adhered to the film. No scattering was observed. Example 3 Instead of 4,4'-methylene-bis(cyclohexyl isocyanate), 231.2 g of isophorone diisocyanate was used and reacted with the polyol for 15 minutes in the same manner as in Example 1. Next, 36.5g of ethylene glycol, 20.6g of trimethylolpropane
was added and mixed with stirring to obtain a homogeneous liquid reaction mixture. This reaction mixture was cured and cured in the same manner as shown in Example 1 to obtain a transparent polyurethane film. The physical properties of this film were as follows.

[Table] Example 4 The liquid reaction mixture of Example 3 was heated and cured in the same manner as in Example 2 to obtain a semi-cured film. This film was combined with glass in the manner described in Example 2 to create a bilayer. When the obtained bilayer was subjected to a penetration resistance test, the steel balls did not penetrate, the broken glass was adhered to the film, and no scattering was observed. Example 5 As polyols, 226.5g of polyoxypropylene triol with a hydroxyl value of 56.3 and 226.5g of polycaprolactone diol with a hydroxyl value of 56.7
Example 1 was carried out in the same manner as in Example 1 except that a mixture of g was used. The physical properties of the obtained polyurethane film were as follows.

【table】

[Table] Example 6 The semi-cured film obtained in Example 5 was combined with glass to create a bilayer. When this film was subjected to the penetration resistance test shown in Example 2, the steel balls did not penetrate, the broken glass was adhered to the film, and no scattering was observed.

Claims (1)

[Claims] 1. Average molecular weight 1000 to 5000, average number of functional groups (f)
For producing a transparent laminate obtained by reacting at least three components: a mixture of a high molecular weight diol with 2.1≦f≦3.5 and a trifunctional or higher functional high molecular weight polyol, a chain extender and/or crosslinking agent, and a polyisocyanate compound Polyurethane sheet with a thickness of 0.1~5.0mm. 2. The sheet according to claim 1, wherein the polyurethane sheet has not yet been completely cured. 3 Average molecular weight 1000-5000, average number of functional groups (f)
A thickness of 0.1 to 5.0 mm obtained by reacting at least three components: a mixture of a high molecular weight diol with 2.1≦f≦3.5 and a trifunctional or higher functional high molecular weight polyol, a chain extender and/or crosslinking agent, and a polyisocyanate compound. A glass-polyurethane laminate comprising at least two layers: a polyurethane sheet layer and a glass sheet layer present on one side thereof. 4. The laminate according to claim 3, wherein the glass sheet layer is present on one side of the polyurethane sheet layer and the other side is exposed.