JPS5863445A - Manufacture of polyurethane laminate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyurethane laminate composed of polyurethane and a substrate, and particularly to a transparent polyurethane laminate composed of at least two sheets of transparent polyurethane and glass sheets. be.

A laminate of a glass sheet and a synthetic resin sheet is well known as safety glass. For example, a laminate having a five-layer structure of glass-bolyvinyl butylene glass is widely used as safety glass for automobiles. The synthetic resin layer laminated between such glass sheets is called an interlayer film, and various synthetic resins such as polyvinyl butyral, polyurethane, and others have been used or proposed. On the other hand, in a laminate made of glass and synthetic resin, one side is glass and the other side is synthetic resin, such as a laminate with an exposed synthetic resin layer, such as glass-synthetic resin or glass-synthetic resin-glass-synthetic resin. The constructed laminate is attracting attention for applications such as automobile safety glass. This laminate is believed to be even safer than traditional double-sided glass laminates. For example, if this laminate is used as a windshield for a car with the synthetic resin side facing the inside of the car, there will be fewer lacerations and cuts when a driver collides with the windshield, and even if the glass is broken. It is thought that this will reduce the chance of fragments of lath scattering inside the car. Such a laminate in which one side is glass and the other side is synthetic resin is referred to as "Zuzu-eraser glass", and a laminate in which both sides are glass using an interlayer film is hereinafter referred to as "laminated glass".

Regarding pie layer glass, for example, Japanese Patent Application Laid-Open No. 1986-
41425, JP 48-25714, JP 49-54910, and JP 55-27
There is a description in Publication No. 671. As can be seen from the known side, the exposed synthetic resin layer (hereinafter referred to as a pie 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 is obtained by reacting a high molecular weight diol, a chain extender, a crosslinking agent, and a diisocyanate compound.A single layer of pie layer needs to firmly adhere to glass.However, if a single layer of thermosetting polyurethane is used as a pie layer, There is a problem that it does not adhere strongly to glass.On the other hand, thermoplastic polyurethane adheres strongly to glass, but since one side of the silver layer used as the pie layer is exposed, the nature of that surface becomes a problem. Thermoplastic polyurethane has insufficient weather resistance and is easily attacked by solvents.

Regarding these problems, please refer to the above-mentioned Japanese Patent Application Laid-Open No. 55-27671.
It is explained in detail particularly on pages 6 to 7 of the publication.

In order to solve the above problems, the invention described in Japanese Patent Application Laid-Open No. 55-27671 consists of a pie layer consisting of two layers of polyurethane, the surface of which is made of thermosetting polyurethane, and the surface that is bonded to glass made of thermoplastic polyurethane. We are trying to solve the problem by doing this. Since both polyurethanes adhere strongly, this invention solves the problem of adhesion of the pie layer to glass and surface properties. However, it is not considered that all problems have been completely solved by this invention. For example, the present 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 the 15th line of the lower right column on page 10 of this bulletin to the 14th line of the upper right column on page 11, one sheet may be poured with the other liquid to integrate it, or one sheet may be mixed with a solvent. It requires a method such as dissolving it and applying it to the other surface.

The present inventor conducted various research studies in order to solve the problems of adhesion with glass and surface properties, and also to solve the problems in manufacturing or processing the above-mentioned polyurethane sheet. As a result, by using a specific cross-linking agent, polyurethane has thermoplastic properties until it is integrated with glass and becomes thermosetting polyurethane after it is laminated and integrated with glass. We have discovered a laminate. This temporarily thermoplastic polyurethane sheet or film is hereinafter referred to as a "preformed sheet". Note that a sheet and a film are distinguished by their thickness, but since the boundary between the two is not necessarily clear, in the present invention, a sheet having a thickness of 0.21111 or more is referred to as a sheet.

In the following explanation, we will mainly explain the sheet (this sheet may be used as a substitute for film in some cases).

The present invention relates to a method for producing a polyurethane laminate using this preformed sheet. Although this method is suitable for manufacturing pie layer glass as described above, it is not limited to that manufacturing method, and can be used for other transparent laminates or various laminates that are not limited to transparent ones. This method can also be applied to the production of.

The above-mentioned specific crosslinking agent is a hydroxyl group-containing compound having at least 5 functional groups, which has at least two types of hydroxyl groups with different reactivities and has two hydroxyl groups with high reactivity. The reactivity of hydroxyl groups with respect to isocyanate groups varies depending on the primary hydroxyl group, secondary hydroxyl group, and quintuary hydroxyl group, and decreases in this order. Therefore, as an example of the above-mentioned specific crosslinking agent, primary hydroxyl group 2
To describe the present invention as a pentahydric alcohol having one hydroxyl group and one 5th hydroxyl group, the preformed sheet is prepared by adding a diisocyanate, a high molecular weight diol, a chain extender (e.g., a dihydric alcohol), and a crosslinking agent, usually a catalyst. Obtained by reacting in the presence of In this reaction, it is possible to carry out the reaction under conditions in which the 5th class hydroxyl group of the crosslinking agent substantially does not react and the two primary hydroxyl groups react substantially entirely. The polyurethane obtained under these reaction conditions is a substantially uncross-biased polyurethane and has thermoplastic properties.

A preformed sheet obtained by forming this polyurethane into a sheet can be firmly adhered to a substrate such as a glass sheet. That is, by crushing the preformed sheet and the substrate and heating and pressurizing them, a laminate in which both are bonded and integrated into a logging body is obtained. Moreover, by setting the heating and pressurizing conditions during IFMm to such a condition that the unreacted 5th-class hydroxyl groups substantially react, the polyurethane is crosslinked and a polyurethane with excellent surface properties can be obtained.

The present invention relates to a method for producing a polyurethane laminate as described above, that is, a method for producing a polyurethane N-layer body in which a polyurethane sheet or film and a substrate are integrated as a body layer. Essential components include a molecular weight diol, a chain extender, and a crosslinking agent having at least five hydroxyl groups, one or more of which is a hydroxyl group with lower activity than either of the other two hydroxyl groups. A polyurethane sheet or film is produced using a polyurethane raw material with the following conditions: one or more of the low-activity hydroxyl groups of the cross-linking agent are not substantially reacted, and then one or more of the cross-linking agents are This is a method for producing a polyurethane laminate, which comprises laminating and integrating the polyurethane sheet or film and a substrate under conditions in which the less active hydroxyl groups of the polyurethane substantially react.

As mentioned above, the crosslinking agent has two highly active hydroxyl groups and one or more less active hydroxyl groups. The level of activity of hydroxyl groups is relative; if a highly active hydroxyl group is a primary hydroxyl group, a less active hydroxyl group is a 5th-class hydroxyl group or a secondary hydroxyl group.
group', and when the highly active hydroxyl group is a secondary hydroxyl group, the less active hydroxyl group is a 5th-class hydroxyl group.The activities of the two highly active hydroxyl groups may be different, but the The lower hydroxyl group needs to be lower than any of the highly active hydroxyl groups.For example, if the highly active hydroxyl groups are a primary hydroxyl group and a secondary hydroxyl group, the less active hydroxyl group is 5.
It must be a grade hydroxyl group. Further, when there are two or more hydroxyl groups with low activity, their activities may be different, but each of them must be lower than either of the two hydroxyl groups with high activity. In addition, differences in the activity of hydroxyl groups may occur in addition to differences in primary, secondary, and 5th-class activities.

For example, even if the secondary hydroxyl groups are the same, their activities may differ due to the position of the hydroxyl group, steric hindrance, or other reasons. The difference in the activity of the hydroxyl groups in the crosslinking agent may be such that it can be distinguished depending on conditions such as the two reaction conditions. However, under normal conditions, it is often difficult to distinguish between the two. Therefore, it is easier to adjust the conditions if the difference in activity between a highly active hydroxyl group and a less active hydroxyl group is as large as possible. In that sense, a preferred crosslinking agent is a crosslinking agent having two primary or secondary hydroxyl groups and one 5th class hydroxyl group,
Particularly preferred is a crosslinking agent consisting of a pentahydric alcohol having two primary hydroxyl groups and one 5th class hydroxyl group.

The crosslinking agent is a compound having at least 5 hydroxyl groups,
In particular, a relatively low molecular weight polyhydric alcohol is preferred. Examples of crosslinking agents other than polyhydric alcohols include polyhydric alcohols having a nitrogen atom such as amino alcohols, compounds in which part or all of the hydroxyl groups are phenolic hydroxyl groups, and relatively low molecular weight polyether polyols and polyester polyols. be. Examples of pentahydric alcohols that can be used as crosslinking agents in the present invention include glycerin, 1.5.5-)dihydroxy-
3-methylpentane, 1.2.6-hexandriol, 2.2-bis(hydroxymethyl)butanol-5,
Examples include 1,5,6-hexandriol. Among these, preferred are pentahydric alcohols having 10 or less carbon atoms and having two primary hydroxyl groups and one 5th class hydroxyl group, such as C+,
5.5-)dihydroxy-5-methylpentane and the like.

The purpose of using the specific crosslinking agents mentioned above is to ensure that the polyurethane in the preformed sheet has thermoplastic properties (i.e., a substantially linear polymer) and that the polyurethane in the laminate is thermoset ( In other words, it is a network polymer)
The goal is to satisfy two requirements. Polyurethane, which has thermoplastic properties, adheres strongly to the substrate.

Therefore, if the polyurethane of the preformed sheet has thermoplastic properties (i.e., is essentially a linear polymer), the crosslinking agent therein must be a chain extender, i.e., the divalent hydroxyl groups must have reacted. It seems necessary to have something. For this purpose, it is considered that the reaction of the less active hydroxyl groups must be suppressed during the production and storage of the preformed sheet. Therefore, it is necessary to adjust conditions for this purpose, such as temperature conditions.

For example, measures such as manufacturing preformed sheets at relatively low temperatures to suppress the reaction of less active hydroxyl groups, and storing the finished preformed sheets at a temperature at which less active hydroxyl groups do not cause reactions may be adopted. Recruitment is required. By adjusting conditions such as temperature, polyurethane with thermoplastic properties can be obtained without substantially reacting the less active hydroxyl groups, but this "without substantially reacting" requires theoretical perfection. It's not something you do. That is, even if some of the less active hydroxyl groups react, the thermoplastic properties are not immediately lost, and even if some of the more active hydroxyl groups do not react, a polyurethane with thermoplastic properties cannot be obtained. It's not a thing. This meaning in the present invention is that as long as the polyurethane has thermoplastic properties (that is, it has adhesive properties with the substrate), some of the hydroxyl groups with low activity may be reacted, and the polyurethane is a sheet-like molded product (preformed). All highly active hydroxyl groups do not need to be completely reacted as long as the sheet remains intact.

The conditions under which at least one low hydroxyl group of the crosslinking agent does not substantially react are the conditions that need to be adjusted in order not to lose the thermoplastic properties of the preformed sheet obtained as described above. means.

It requires, for example, that mild reaction conditions and storage atmospheres be employed in the production and storage of preformed sheets. These conditions include conditions such as temperature and time during reaction and storage, which often vary depending on the type of raw materials such as crosslinking agent and diisocyanate. This condition also depends on the type of raw materials such as catalysts.

For example, a highly active catalyst can inhibit bt even when a low-active hydroxyl group
The use of a catalyst of appropriate activity may be necessary; setting appropriate conditions is easily determined by examining the adhesion of experimental preformed sheets to the substrate.

When the preformed sheet and the substrate are laminated and integrated, unreacted hydroxyl groups of the crosslinking agent with low activity are reacted. Lamination and integration is usually performed by applying pressure and heating. Heating and pressurization may be carried out simultaneously or separately, but it is not preferable that only heating precedes the reaction of less active hydroxyl groups by the time pressurization is carried out.15 Usually, under pressure Heating is carried out, preferably both simultaneously or preceded by pressurization. When heating precedes pressurization, it is preferable that the period between them be as short as possible or that the temperature of the preceding heating be low.

The preformed sheet is manufactured from a raw material containing diisocyanate, high molecular weight diol, and chain extender as essential components in addition to the crosslinking agent. In addition to these essential components, a catalyst, a coloring agent, and other subcomponents can be used, and the catalyst is often an essential component. However, methods such as manufacturing a preformed sheet using a catalyst that is inactive at low temperatures and activating the catalyst by heating during lamination and integration with the substrate can also be used. It is not necessarily an essential ingredient.

As the diisocyanate, aromatic, aliphatic, alicyclic and other diisocyanates can be used. However, non-yellowing alicyclic or aliphatic diisocyanates are particularly preferred for producing transparent laminates.

The diisocyanate may also contain a small amount of triisocyanate or polyisocyanate with higher functionality. Further, the diisocyanate may be a so-called modified isocyanate that has been modified by proper treatment or a compound. Specific diisocyanates include, for example, methylene-bis(cyclohexyl isocyanate,
Examples include anate λ, inphorone diisocyanate, cyclohexylmethane diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, and tolylene diisocyanate.

In particular, alicyclic diisocyanates such as methylene-bis(cyclohexyl isocyanate) and inphorone diincyanate are preferred for producing pie layer glass.

Further, two or more of these diisocyanates can be used in combination; for example, a combination of methylene-bis(cyclohexyl isocyanate) and inphorone diisocyanate is effective for improving transparency.

Preferred high molecular weight diols include diols with molecular weights of about 800 to 6, such as polyester diols, polyether diols, and polycarbonate diols. As the polyester diol, those obtained by the reaction of dihydric alcohol and dibasic acid, and ring-opened polymers of cyclic esters are preferable.

For example, polyester polyols obtained by the reaction of ethylene glycol, propylene glycol, 1,4-butanediol, and other dihydric alcohols with adipic acid, heptatalic acid, maleic acid, and other dibasic acids, and ring-opening polymers of ε-caproladone. There is such a thing as merging. Polyether diols include polyether diols obtained by adding ethylene oxide, propylene oxide, and other alkylene oxides to dihydric alcohols and other initiators having two active hydrogens, and ring-opening polymers of cyclic ethers such as tetrahydrofuran. is preferred. In addition, polycarbonate diols and hydrocarbon polymers having hydroxyl groups at the ends are also used.

The chain extender is preferably a low molecular weight dihydric alcohol, such as ethylene glycol, 1,4-butanediol, propylene glycol, 1,2-butanediol,
Other dihydric alcohols having 6 or less carbon atoms are suitable.

Particularly preferred chain extenders are ethylene glycol and 1,4-
Butanediol.

The amount of these raw materials used is not particularly limited, but
The preferred ranges are as follows.

The polyol component (i.e., high molecular weight diol, chain extender, and crosslinking agent) is suitably a mixture of ~ parts by weight of the chain extender and ~ parts by weight of the crosslinking agent based on 100 parts by weight of the high molecular weight diol. A mixture of ~ parts by weight of the chain extender and ~ parts by weight of the crosslinking agent per 100 parts by weight is preferred. The amount of diisocyanate relative to the polyol component is preferably from 95 to 110, particularly preferably from 98 to 105, in terms of isocyanate index (number of incyanate groups per 100 water % groups).

Catalysts commonly used in the production of preformed sheets include tertiary amine catalysts and organometallic compound catalysts, which can be used alone or in combination. Examples of the catalyst include triethylenediamine, triethylamine, N-methylmorpholine, stannath octoate, dibutyltin dilaurate, and lead acetate.

The preformed sheet is obtained by reacting the above raw materials and forming the reaction mixture into a sheet by casting or the like. This preformed sheet can not only be immediately integrated with the substrate for logging, but also can be used after being stored. When storing ε, it is preferable to store it at a relatively low temperature as described above, and since it also contains matte-free isocyanate groups, it is preferable to store it in an atmosphere with little moisture.

Various substrates can be used as the substrate. A particularly preferred substrate is a glass sheet as described above, but the substrate is not limited thereto, and polycarbonate sheets, acrylic resin sheets, and other highly transparent synthetic resin sheets and films can also be used. Furthermore, if the purpose is not to produce a transparent glaze layer, non-transparent sheets or films of various yuzu synthetic resins can also be used as the substrate.

Further, the substrate may be a laminate composed of two or more blades. For example, taking a glass sheet as an example, it may be a laminated glass composed of a polyvinyl butyral interlayer and two glass sheets. The desired polyurethane laminate can be obtained by stacking these substrates and preformed sheets and heating them under pressure.

The polyurethane laminate in the present invention is composed of at least one polyurethane layer and at least one substrate layer.
7ru. Preferably, this polyurethane layer is a single layer, and that layer is preferably on the surface of the laminate (ie, not in between two substrate layers). The substrate layer may have a multilayer structure as described above. A preferred polyurethane laminate in the present invention is a two-layer structure consisting of one polyurethane layer and one glass layer, or a multilayer structure of five or more layers in which one side of at least two surfaces is polyurethane and the other side is glass. The body is made of pie layer glass.

In the above explanation, the case where the polyurethane in the preformed sheet or polyurethane laminate is a sheet (that is, approximately (1, 2 or more) thick) has been explained, but it is a film (approximately 0.2 layers thick, 1 layer or more). Even if the polyurethane laminate is less than 100%, it is possible to produce a similar polyurethane laminate using the same method.

However, the present invention is not limited to these examples.

Example 1 Polybutylene adipe) 100 having a hydroxyl value of 55
09 was stirred and degassed under vacuum at 110° C. for 2 hours to perform deaeration and dehydration.

In addition, 4,4'-methylene-bis(cyclohexyl isocyanate) 8279, dibutyltin dilaure)
0.19 was added, and the mixture was reacted for 15 minutes at 80°C under a nitrogen stream. Next, add ethylene glycol 143 to this reaction mixture.
g, 1,5.5-) dihydroxy-3-methylpentane 509 was added thereto, and the mixture was rapidly stirred and mixed. An exotherm was observed with the start of the reaction, and after the reaction mixture was thoroughly mixed and became substantially homogeneous, the liquid reaction mixture was cast onto a glass plate to a thickness of 0.611 Jl and poured with nitrogen. A preformed sheet was produced by reacting in an atmosphere at 100° C. for 5 hours. This preformed sheet showed a high yield of unreacted incyanate in an infrared spectrometer, and the elevated 7c1-
It also showed sufficient flowability at 180°C in a tester.

Next, this sheet is peeled off from the glass plate, and the surface of the peeled sheet that was exposed when producing the sheet is adhered to the glass treated with an adhesion promoter, if necessary, and the other side of the sheet is The surface is aligned with the glass with a fluororesin film bordering it. This non-adhesive glass laminate was heated for 50 minutes at a temperature of 150°C to 180°C and a pressure of 15 atm.
By removing the remaining glass and fluororesin film after treatment for 1 to 2 hours, a pie layer glass consisting of a glass-urethane sheet could be obtained. In the infrared spectrum of this urethane sheet, almost no absorption of isocyanate groups observed before the adhesive treatment was detected. In addition, this exposed urethane sheet is ANSI
Z-26K [setti bOH/MeOH=10
/1 (/V) CCt, kerosene or other solvent was crushed for 1 minute and the solvent was wiped off, but no change was observed.

Furthermore, a 2.26119* ball was dropped from a height of 4 m at 20°C on this laminate with a size of 5Qc+n x 5Qcm (the side where the urethane sheet receives the steel ball).
The steel ball was retained without penetrating, and almost no glass was observed to be scattered.

Example 2 In 111+H, instead of 4,4'-methylene-bis(cyclohexyl isocyanate), isophorone diisocyanate was used at 7989, and ethylene glycol was added at 172.
9.1.5.5-Trihydroxy-5-methylpentane was used in the same manner as in Example 1 except that 509 was used, and it passed the glass-urethane test.

Example 5 In Example 1, 1.5.5-)dihydroxy-6
- Proceed in the same manner as in Example except that 50 g of glycerol is used instead of methylpentane, 8559 of 4,4-methylene-bis(cyclohexyl isocyanate), and 1359 of ethylene glycol. I passed the exam.

Within the agent 1) Akira Agent Ryo Hagihara -

Claims (1)

[Claims] t. A method for producing a polyurethane laminate in which a polyurethane sheet or film and a substrate are laminated together, comprising a diisocyanate, a high molecular weight diol, a chain extender, and θ having at least five hydroxyl groups. In addition, a polyurethane raw material containing as an essential component a crosslinking agent in which one or more of the hydroxyl groups is a hydroxyl group with lower activity than either of the other two hydroxyl groups is used, and one or more of the crosslinking agents A sheet or film of polyurethane is produced under conditions in which the less active hydroxyl groups do not substantially react, and then the polyurethane is produced under conditions in which one or more less active hydroxyl groups of the crosslinking agent substantially react. A method for producing a polyurethane laminate, which comprises laminating and integrating a sheet or film and a substrate. 2. The method according to claim 1, wherein the crosslinking agent is a pentahydric alcohol having one tertiary hydroxyl group and two primary or secondary hydroxyl groups. 3. The method according to scope 1 of the patent application, characterized in that the polyurethane is transparent polyurethane. 4. The method of claim 1, wherein the substrate is a glass sheet. 5. The method according to claim 1, wherein the polyurethane glazed laminate is a laminate consisting of polyurethane on one side and glass on the other side.