JPH0671826A - Glazing material for vehicle - Google Patents

Abstract

PURPOSE:To improve resistance to shock without spoiling transparency and rigidity by a method wherein a laminated structure, constituted of a layer consisting of the copolymer of glutarimide and methyl methacrylate and a layer consisting of transparent polymer having resistance to shock, is provided with a hardened film on the surface thereof. CONSTITUTION:A glazing material for vehicle is obtained by a method wherein a laminated structure, constituted of the copolymer of gultarimide shown by a formula (in the formula, R1, R2, R3 show substitutable or non-substitutable alkyl group or aryl group having hydrogen molecule or carbon number of 10-20 respectively) and methyl methacrylate or methacrylate resin and a layer consisting of transparent polymer having resistance to shock, is provided with a surface hardened film on the surface thereof directly or through a primer layer. Polymer, selected from a group consisting of polycarbonate, polyacrylate, polyester and silicone, is employed as the transparent polymer provided with resistance to shock.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle glazing material having a multilayer structure.

[0002]

Glass has been used as a glazing material in the vehicle industry for many years.

[0003]

Recently, in the vehicle industry, there has been an urgent need to improve fuel efficiency due to global environmental problems. As one countermeasure, reduction of vehicle weight has been studied. However, conventional glass materials are used as glazing materials. It is possible to reduce the weight by using resin.

The copolymer of glutarimide and methyl methacrylate, and methacrylic resin have a great feature in transparency similar to glass, and are relatively excellent in weather resistance, scratch resistance and rigidity among thermoplastic resins, It is a promising alternative to glass. However, these resins are brittle resins, have poor impact resistance, and, if broken, have fragments that have sharp edges, which may be harmful to passengers, and it is difficult to use them as a substitute for glass. As a method of improving the impact resistance of these resins, a method of adding and modifying a rubber component is generally known. Although it is possible to improve the impact resistance by increasing the addition amount of the rubber component by such a method, the elastic modulus tends to decrease. It is desired that the glazing material has as high rigidity (elastic modulus) as possible in terms of deflection due to wind pressure during traveling, and improvement of impact resistance due to the rubber component remains a problem in the case of the glazing material.

Resins such as polycarbonate, polyarylate, polyester, polyurethane, polyvinyl butyral, polyolefin and polyamide are resins having impact resistance and transparency superior to those of glutarimide / methyl methacrylate copolymers and metacle resins. But
Since the elastic modulus is low, the rigidity is insufficient to use it alone as a glazing material. In addition, the copolymer of glutarimide and methyl methacrylate and methacrylic resin are relatively excellent in weather resistance and scratch resistance among thermoplastic resins, but they are inferior to glass, and therefore, for glazing materials whose visibility is important. Conventionally, it has been difficult to use.

[0006]

In view of the above-mentioned problems, the inventors of the present invention have made extensive studies to use a resin as a vehicle glazing material, and as a result, have found that a specific glutarimide-methyl methacrylate copolymer and impact resistance are used. It has been found that the problems can be solved by combining transparent polymers having the above, and the present invention has been accomplished.

Accordingly, the present invention provides the following general formula:

[Chemical 2] (In the formula, R ₁ , R ₂ and R ₃ are each a hydrogen atom or a carbon number 1
To 20 substituted or unsubstituted alkyl or aryl groups. ) Is a copolymer of glutarimide and methyl methacrylate, or a layer made of a methacrylic resin and a layer made of a transparent polymer having impact resistance, directly on the surface of a laminated structure or through a primer layer. The transparent polymer having a surface-hardened film and having impact resistance is characterized by being a polymer selected from the group consisting of polycarbonate, polyarylate, polyester, polyurethane, polyvinyl butyral, polyolefin, polyamide and silicone. The present invention relates to a laminated structure.

The copolymer of glutarimide and methyl methacrylate used in the present invention is produced by imidizing a methacrylic resin, and has excellent optical properties, scratch resistance, and weather resistance inherent to the methacrylic resin. The heat resistance is improved without deteriorating. Further, the copolymer has a high elastic modulus, excellent rigidity, and a relatively small coefficient of linear expansion, and is therefore suitable as a vehicle glazing material. A method for producing a copolymer of glutarimide and methyl methacrylate is described in, for example, Japanese Patent Publication No. 42362/1990. The manufacturing method described here includes a reaction step of causing a condensation reaction between polymer chains of a methacrylic resin by reacting a methacrylic resin with an amine under specific conditions, and an imidized methacrylic acid produced in the reaction step. It consists of separating and removing volatile substances from the reaction product containing the resin.

Methacrylic resin is defined in JIS K 6717 as containing 80% or more of polymethylmethacrylate, but the methacrylic resin used in the present invention is not limited to 80% or more of the main component. Known modified acrylic resins such as heat resistant methacrylic resin and impact resistant methacrylic resin can also be used.

In the constitution of the laminated structure of the present invention, a layer made of a copolymer of glutarimide and methyl methacrylate or a methacrylic resin is an A layer, and a layer made of a transparent resin having impact resistance is a B layer. If the structure includes one or more layers A and B, A / B, A / B / A, B / A / B,
The number and order of layers such as A / B / A / B can be freely set. The resins selected for the A layer and the B layer are not limited to one type, but may be configured as A / B / B '/ B / A, for example. To improve the impact resistance, it is effective to position a B layer having excellent impact resistance such as A / B / A between the A layers and increase the number of laminated layers.

Although the lamination thickness ratio is arbitrary, the ratio of the total thickness of the A layer and the total thickness of the B layer in the laminated structure is A: B = 100:
When it is 1 to 5: 1, the impact resistance is sufficiently improved. Increasing the thickness ratio of the B layer has a great effect on the impact resistance, but the rigidity may be lowered.

For example, when a copolymer of glutarimide and methyl methacrylate is selected for the layer A and a resin having a heat resistance close to that of the polycarbonate is selected for the layer B, the lamination method is disclosed in Japanese Patent Application Laid-Open No. Hei.
The coextrusion method proposed in Japanese Patent No. 19142 is possible. Also, a method of laminating a methacrylic resin and a polycarbonate film in a mold using an injection molding machine, or a method of laminating a methacrylic resin sheet with a urethane adhesive, or a method of co-loading glutarimide and methylmethacrylate Various laminating methods such as a method of laminating the united product and polyvinyl butyral with a hot press can be adopted.

Since the surface of the laminated structure of the present invention is inferior in abrasion resistance, a hard coat treatment is carried out to form a surface-hardened film on the surface. The surface hardened film is a surface hardened inorganic film,
Ox (x≤2) film, SiyNz (y≤3, z≤4) film and amorphous carbon film are preferable, and these are formed by plasma CVD method.

The plasma CVD method is a method in which a raw material gas is introduced into a plasma state having a high energy density to decompose it, and a target material is coated on the surface of a substance to be coated with a chemical reaction. Any of the above can be used, and for example, a parallel plate electrode type, a capacitive coupling type or an inductive coupling type can be used. The device pressure is
A range of 10 ^-2 to 1 Torr is preferred, but 2 x 10 ^-1 Torr
The degree is particularly preferable. Further, the power supply frequency can be widely used from the audio wave to the microwave range.

When a SiOx (x≤2) film is formed as a surface-hardened film, silane gas or an organic silicone compound is preferably used as a silicon raw material. When a silane gas is used, N ₂ O gas is used as an oxygen raw material. When an organic silicone compound is used, it is preferable to use N ₂ O gas or O ₂ and O ₃ gas in combination as the oxygen raw material.

The organosilicon compound used in the present invention is preferably arbitrarily selected from those in which a group containing carbon is bonded to silicon. Suitable organic silicone compounds are tetraethoxysilane, tetramethyldisiloxane, dimethoxydimethylsilane, methyltrimethoxysilane, tetramethoxysilane, ethyltrimethoxysilane, diethoxydimethylsilane, methyltriethoxysilane, octamethylcyclotetrasilane, etc. Used for. One of these organic silicone compounds may be used alone, or two or more thereof may be used in combination. If the organosilicon compound used is a liquid at room temperature, the entire container containing the organosilicon compound is heated and vaporized, and the vapor is controlled at a predetermined flow rate and introduced into the device together with a constant Ar gas (direct vaporization). Introduction method) or using a certain amount of Ar gas as a carrier gas and bubbling in a temperature-controllable container containing an organosilicon compound and introducing it together with the organosilicon compound vapor into the device (bubbling with carrier gas). Introduction method) Either method is suitable.

As a surface-hardened film, SiyNz (y ≦ 3, z ≦
4) When forming a film, silane gas is preferably used as a silicon raw material and N ₂ or NH ₃ gas is suitably used as a nitrogen raw material. When forming an amorphous carbon film as the surface-hardened film, a hydrocarbon gas is preferably used as the carbon raw material. When the concentration of hydrocarbon gas is high, it is possible to introduce H ₂ gas at the same time and dilute it.

The above-mentioned surface-hardened film may be directly formed on the surface of the laminated structure, but a primer layer may be present in the middle for the purpose of improving the adhesion of the surface-hardened film. As such a primer layer, one having good adhesion between the laminated structure and the surface-cured film is preferable, for example, an acrylic type (for example, PH-9 manufactured by Toshiba Silicone Co., Ltd.).
1, solid content; thermoplastic acrylic polymer, solvent: ethyl cellosolve, cellosolve acetate), urethane type, polyester type, etc. can be used.

The method for producing the surface-hardened film is exemplified below. The manufactured laminated structure of the present invention is first degreased with isopropyl alcohol, and then rinsed with pure water and dried by nitrogen blowing to be washed.
After the completion of cleaning, the substrate is set in the plasma CVD apparatus, the apparatus is evacuated, and the substrate temperature is raised to 100 ° C. and kept for 5 minutes for degassing the substrate at a vacuum degree of 2 × 10 ^-5 Torr. After that, the temperature is returned to room temperature, and evacuation is continued until the degree of vacuum reaches 2 × 10 ^-6 Torr.

When the degree of vacuum reaches 2 × 10 ^-6 Torr, preparation for forming a surface-hardened film is subsequently started. A raw material gas for forming a surface-hardened film is introduced into the apparatus, and when the gas flow rate is stable, electric power is applied to generate plasma to form a surface-hardened film. The thickness of the surface-hardened film is preferably 1 μm or more, and particularly preferably in the range of 1 to 8 μm.

When a primer layer is provided between the laminated structure and the surface-hardened film, after the cleaning of the substrate is completed, a flow coating method,
It is applied by any one of a spray method, a dipping method and a spin coating method. Either method is preferable, and the film thickness is preferably 1 μm or more. After application, it is left standing for an arbitrary time and air-dried to form. After that, the laminated structure is inserted into the plasma CVD apparatus in the same manner as described above to form a surface-hardened film. The abrasion resistance of the surface-cured film thus obtained was measured by a haze meter to measure the change in haze (clouding) value ΔH% at 1000 rotations according to the Taber abrasion test method. The smaller the change in haze value, the higher the abrasion resistance. Is judged to be good.

[0022]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. Examples 1 to 3 Samples Nos. 1, 2 and 3 of 5 mm thick laminated structure of Examples 1, 2 and 3 consisting of the following A layer 1 and B layer 2 shown in FIGS. , Impact resistance, rigidity, transparency and abrasion resistance were tested.・ Material A layer: Copolymer of glutarimide and methyl methacrylate (PMI resin manufactured by Mitsubishi Rayon) B layer: Polycarbonate (both thickness 0.2 mm) (GE
LEXAN) -Lamination method Extrusion molding by co-extrusion-Surface treatment method The produced laminated structure was first degreased with isopropyl alcohol, and then rinsed with pure water and dried with nitrogen blow to wash. After cleaning, this substrate is plasma C
After setting in the VD device, the device is evacuated and the degree of vacuum is 2
The substrate temperature was raised to 100 ° C. for 5 minutes for degassing the substrate at × 10 ^-5 Torr. Then, the temperature was returned to room temperature, and evacuation was continued until the degree of vacuum reached 2 × 10 ⁻⁶ Torr. Vacuum degree is 2 × 10
When it became ^-6 Torr, preparations for the formation of the surface hardened film were subsequently started. A raw material gas for forming a surface-hardened film was introduced into the apparatus, and when the gas flow rate was stable, electric power was applied to generate plasma to form a surface-hardened film. The thickness of the surface-hardened film was 5 μm. -Impact resistance test The impact strength was measured using a Dynestadt impact tester. A hammer was set to a full scale of 20 Kgf-cm with a test piece width of 10 mm and a distance between the impact blade and the sample holder of 8.75 mm.
The results are shown in Table 1. -Rigidity The elastic modulus was measured by a 3-point bending test.
The results are shown in Table 2. -Transparency The total light transmittance was measured by the standard light source C. The results are shown in Table 3. -Abrasion resistance A change in haze (clouding) value ΔH% at 1000 rotations was measured by a Taber abrasion test. The results are shown in Table 4.

Comparative Example 1 A coating agent having a siloxane bond, which has been conventionally used as a surface-cured layer of plastic in a structure composed of a glutarimide-methylmethacrylate copolymer single substance 1 having a thickness of 5 mm shown in FIG. Silicone-based coating agent mainly composed of a co-partial hydrolyzate of CH ₃ Si (OCH ₃ ) ₃ and tetraalkoxy silicon or a mixture of each partial hydrolyzate, “Sumiuni” (Sumitomo Chemical Co., Ltd.,
(Trade name) was applied by a dipping method, allowed to stand for 20 minutes to air dry, and then held at 100 ° C. for 60 minutes to form a silicone-based coating layer of 8 μm. Table 4 shows the change in haze value ΔH% at 1000 rotations by the Taber abrasion test.

Similar results were obtained using "Tosgard" (trade name, manufactured by Toshiba Silicone Co., Ltd.) as a coating agent mainly composed of a mixture of methylsilsesquisiloxane and colloidal silica.

Next, impact resistance, rigidity and transparency were tested under the same conditions as in Examples 1 to 3, and the results obtained are shown in Table 1, Table 2 and Table 3, respectively. Further, a wear resistance test was conducted under the same conditions as in Examples 1 to 3, and the results obtained are shown in Table 4.

Example 4 A laminated structure having a thickness of 6 mm consisting of the following methacrylic resin layer 3 of layer A and polycarbonate film 2 of layer B shown in FIG. 3 was prepared and tested for impact resistance.・ Material A layer: Methacrylic resin (Acrypet VH made by Mitsubishi Rayon) B layer: Polycarbonate film (0.2 mm thickness) (made by Mitsubishi Rayon) ・ Lamination method Injection molding, in-mold molding ・ Surface treatment method Same as Example 1 ・ Resistance Impact test Drop ball type impact test. A 100 × 100 mm test piece was fixed on the entire circumference with an 80 × 80 mm frame, and a 286.5 g steel ball was allowed to fall freely in the center of the test piece, and the cracking of the test piece was observed.
Also, the length of cracks generated per test piece was measured.

As a result, a crack was generated in the A layer but not in the B layer, and since the A layer and the B layer were in close contact with each other, the broken pieces of the A layer were not scattered. It was Moreover, the measurement result of the crack length is shown in FIG.

COMPARATIVE EXAMPLE 2 A test was carried out under the same conditions as in Example 4 for a structure composed of a simple substance 3 made of methacrylic resin having a thickness of 6 mm shown in FIG. As a result, when the steel ball was dropped from a height of 120 cm or more, fragments were scattered. Figure 5 shows the results of crack length measurement.
Shown in. The reason why the crack height reached 120 cm or more and the crack length did not change significantly was that the crack reached the edge of the test piece. The surface treatment method is the same as in Comparative Example 1.

The rigidity and the transparency were evaluated in the same manner as in Examples 1 to 3, and the impact resistance was evaluated in the Dynestadt impact tester similar to Examples 1 to 3 in addition to the falling ball test. The obtained results are shown in Tables 1-3.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

[0033]

[Table 4]

Example 5 Using a laminated structure having a thickness of 6 mm shown in FIG. 6, a test was conducted for impact resistance. -Material A layer: Copolymer of glutarimide and methyl methacrylate (PMI resin made by Mitsubishi Rayon) B layer: Polyvinyl butyral. Thickness after lamination 0.4mm ・ Lamination method Laminate a polyvinyl butyral film (layer B) with a thickness of 0.8mm between two PMI molded plates (layer A) obtained by injection molding and heat at 150 ° C with a press molding machine. Under pressure, they were laminated by pressure. -Impact resistance test Drop ball impact test. A 100 × 100 mm test piece was fixed on the entire circumference with a 80 × 80 mm frame, and a 286.5 g steel ball was allowed to fall freely in the center of the test piece, and the length of a crack generated per test piece was measured. The measurement result is shown in FIG. A crack was generated in the A layer, but no crack was generated in the B layer, and since the A layer and the B layer are in close contact with each other,
No scattering of fragments of the layer A in which cracking occurred was found.

Example 6 Using a laminated structure having a thickness of 6 mm shown in FIG. 7, a test was conducted for impact resistance. -Material A layer: Copolymer of glutarimide and methyl methacrylate (PMI resin made by Mitsubishi Rayon) B layer: Polyurethane adhesive. 0.3mm thickness (manufactured by Nippon Polyurethane Industry) -Lamination method Between two PMI molded plates (layer A) obtained by injection molding, polyester polyol Nipolan 1004 (Nippon Polyurethane Industry) and polyisocyanate Coronate HX (Nippon Polyurethane Industry) 8: 2 weight ratio mixture solution was injected, and the mixture solution was cured in an atmosphere of 80 ° C. to be laminated. -Impact resistance test Drop ball impact test. A 100 × 100 mm test piece was fixed on the entire circumference with a 80 × 80 mm frame, and a 286.5 g steel ball was allowed to fall freely in the center of the test piece, and the length of a crack generated per test piece was measured. The measurement result is shown in FIG. A crack was generated in the A layer, but no crack was generated in the B layer, and since the A layer and the B layer are in close contact with each other,
No scattering of fragments of the layer A in which cracking occurred was found.

Comparative Example 3 A 6 mm thick copolymer of glutarimide and methyl methacrylate (PMI resin manufactured by Mitsubishi Rayon) was tested under the same conditions as in Example 5. The measurement result is shown in FIG.
When steel balls were dropped from a height of 120 cm or more, scattering of debris was observed.

[0037]

EFFECTS OF THE INVENTION According to the present invention, the surface of a laminated structure composed of an A layer made of a copolymer of glutarimide and methyl methacrylate or a methacrylic resin and a B layer made of a transparent polymer having impact resistance. By applying a hard coat treatment to the above and providing a surface-hardened film, it was possible to improve the impact resistance without impairing the transparency and rigidity which are excellent characteristics of the layer A. Further, when the hard code treatment is performed, the wear resistance of the surface of the laminated structure of the present invention can be remarkably improved by using the inorganic film as the surface hardened film.

[Brief description of drawings]

FIG. 1A is a cross-sectional view of a laminated structure of Example 1,
(b) is a sectional view of the laminated structure of Example 2, and (c) is a sectional view of the laminated structure of Example 3.

2 is a sectional view of a structure of Comparative Example 1. FIG.

FIG. 3 is a cross-sectional view of a laminated structure of Example 4.

4 is a sectional view of a structure of Comparative Example 2. FIG.

FIG. 5 is a graph showing the results of a falling ball test performed on the laminated structure of Example 4 and the structure of Comparative Example 2.

FIG. 6 is a side sectional view of a laminated structure used in Example 5.

FIG. 7 is a side sectional view of a laminated structure used in Example 6.

FIG. 8 shows the results of a falling ball impact test used in Examples 5 and 6 and Comparative Example 3.

[Explanation of symbols]

1 A layer (or simple substance) made of a copolymer of glutarimide and methyl methacrylate 2 B layer made of polycarbonate 3 A layer (or simple substance) made of methacrylic resin 4 B layer made of polyvinyl butyral 5 Made of polyurethane adhesive Layer B

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuhiro Hirota 3816 Noborito, Tama-ku, Kawasaki-shi, Kanagawa Mitsubishi Rayon Co., Ltd. Tokyo Research Laboratory

Claims (1)

[Claims] 1. The following general formula: (In the formula, R ₁ , R ₂ and R ₃ are each a hydrogen atom or a carbon number 1
To 20 substituted or unsubstituted alkyl or aryl groups. ) Is a copolymer of glutarimide and methyl methacrylate, or a layer made of methacrylic resin and a layer made of a transparent polymer having impact resistance, directly or through a primer layer on the surface of the laminated structure. Characterized in that the transparent polymer having impact resistance is a polymer selected from the group consisting of polycarbonate, polyarylate, polyester, polyurethane, polyvinyl butyral, polyolefin, polyamide and silicone. Vehicle glazing material.