JP2000044295A - Interlayer for laminated glass and laminated glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an interlayer film for laminated glass which is excellent in blocking resistance during storage and handling workability when an interlayer film is sandwiched between glass plates, and is excellent in deaeration in a pre-compression bonding step. SOLUTION: In an interlayer film for laminated glass in which embosses made of fine irregularities are formed on both surfaces of a thermoplastic resin sheet, at least one surface has an emboss surface roughness of 0 <.
Rvk / Rz≤0.25, Mr2≥90%, Ra = 5.0-5.0
7.0 μm (Rz and Ra are DIN 4768 and 47
62, Rvk and Mr2 are DIN 4762
And the value obtained from the Abbott load curve defined in 4776). In particular, the intermediate film is made of a plasticized polyvinyl acetal resin, and has a creep elastic modulus of 40 ° C.
30 to 40 g / cm ² at 60 ° C. and 7 to 14 g / c
Those satisfying at least one of ² to 5 g / cm ² at m ² and 80 ° C. are preferable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interlayer film for laminated glass on which an emboss having fine irregularities is formed.

[0002]

2. Description of the Related Art Laminated glass obtained by sandwiching an interlayer made of a thermoplastic resin sheet such as plasticized polyvinyl butyral between glass plates and bonding them together is widely used for window glasses of automobiles, aircraft, buildings and the like. I have.

[0003] In this kind of laminated glass, usually, an interlayer film is sandwiched between glass plates and handled by passing through a nip roll (referred to as a handling deaeration method) or put in a rubber bag and suctioned under reduced pressure (a reduced pressure deaeration method). This is manufactured by pre-compression bonding while removing air remaining between the glass plate and the intermediate film, and then performing heating and pressing in an autoclave to perform main compression.

The interlayer of the laminated glass has adhesiveness,
In addition to good basic performance such as weather resistance, penetration resistance, transparency, etc., interlayer films do not block during storage, and handling workability when sandwiching interlayer films between glass plates is good. Further, in order to eliminate air entrapment, it is required that the deaeration in the pre-compression bonding step be good.

Japanese Patent Application Laid-Open No. 10-17338 discloses an interlayer film for laminated glass that meets such a demand, in an interlayer film for laminated glass in which embosses having fine irregularities are formed on both surfaces of a thermoplastic resin sheet. The surface roughness of at least one embossed surface is 0 <Rvk / Rz ≦ 0.2
5. An interlayer film for laminated glass satisfying Mr2 ≧ 90% has been proposed.

[0006] Here, Rz (μm) is DIN 4768.
And Rvk is DIN 47
Represents the reduced valley depth (μm) obtained from the Abbott load curves defined in 62 and 4776, and Mr 2 represents the material component (%) obtained from the Abbott load curves.

[0007]

According to the interlayer film for laminated glass proposed above, the blocking property during storage and the handling workability when the interlayer film is sandwiched between the glass sheets are excellent, and the glass sheet is preliminarily pressed in the pressing step. The air interposed between the intermediate film and the intermediate film is smoothly discharged, and can be sufficiently deaerated. Therefore, the adhesion between the glass plate and the interlayer is good,
A laminated glass with excellent transparency can be obtained.

However, the above performance is improved to a higher level, and particularly under severe conditions such as when manufacturing a laminated glass having a large area, a laminated glass having a large curvature, and increasing the productivity of the laminated glass. Even if there is, it is desirable to be able to respond sufficiently without any trouble.

An object of the present invention is to provide an interlayer film for laminated glass and a laminated glass which are excellent in blocking resistance during storage and handling workability when an interlayer is sandwiched between glass plates, and which are excellent in deaeration in a pre-compression bonding step. Is to provide.

[0010]

An object of the present invention is to provide an interlayer film for laminated glass in which embosses composed of fine irregularities are formed on both surfaces of a thermoplastic resin sheet, and the surface roughness of the emboss on at least one surface is 0 <. Rvk / Rz ≦ 0.25,
Satisfies Mr2 ≧ 90% and Ra = 5.0-7.0 μm
The invention can be achieved by an interlayer film for laminated glass characterized by satisfying the following (invention according to claim 1).

Here, Rz (μm) is DIN 4768
And Rvk is DIN 47
Represents the reduced valley depth (μm) obtained from the Abbott load curves defined in 62 and 4776, and Mr 2 represents the material component (%) obtained from the Abbott load curves. Ra (μ
m) represents the arithmetic average roughness specified in DIN 4762.

Another object of the present invention is to provide an intermediate film made of a plasticized polyvinyl acetal resin, which has a creep elasticity of 30 to 40 g / cm ² at 40 ° C. and 7 to 40 g / cm ² at 60 ° C.
14g / cm ^2, 80 ℃ of 2-5 g / cm ² in by the interlayer film for a laminated glass according to claim 1, characterized by satisfying any one or more can be achieved (claims 2).

Further, the above object can be achieved by a laminated glass characterized by using the interlayer film for laminated glass according to claim 1 or 2 (the invention according to claim 3).

As the thermoplastic resin sheet used in the present invention, a sheet used for a conventional interlayer film for laminated glass is used. Examples include a plasticized polyvinyl acetal resin sheet, a polyurethane-based resin sheet, an ethylene-vinyl acetate-based resin sheet, an ethylene-ethyl acrylate-based resin sheet, and a plasticized vinyl chloride-based resin sheet. These sheets have excellent basic performance required for laminated glass, such as adhesion, weather resistance, penetration resistance, and transparency.

Particularly, a plasticized polyvinyl acetal resin sheet represented by a plasticized polyvinyl butyral resin sheet is preferable. The thickness of these thermoplastic resin sheets is determined in consideration of the penetration resistance and the like required as a laminated glass, and is approximately the same as that of a conventional interlayer film, and is particularly preferably 0.2 to 2 mm.

[0016] At least one surface of the thermoplastic resin sheet is provided with 0 <Rvk / Rz ≦ 0.25, Mr2 ≧
An emboss having fine irregularities satisfying the conditions of 90% and Ra = 5.0 to 7.0 μm is formed. To form such an emboss, an embossing roll method, a profile extrusion method,
An extrusion lip embossing method using melt fracture is employed. In particular, the embossing roll method is suitable for quantitatively obtaining embosses having constant fine irregularities.

The embossed concavo-convex pattern is not particularly limited as long as it satisfies the above specific conditions. In general,
Various fine uneven patterns consisting of a large number of convex portions and a large number of concave portions corresponding to these convex portions are formed, and these concave and convex patterns may be regularly and regularly distributed, and may be irregularly and irregularly. It may be distributed. Further, the heights of the convex portions may be all the same height or different heights, and the depths of the concave portions with respect to the convex portions may be different depths even if they are all the same depth. You may.

The shapes of the projections and depressions are not particularly limited as long as they satisfy the specific conditions.
In general, pyramids such as triangular pyramids, quadrangular pyramids, and cones, truncated triangular pyramids,
It is composed of truncated pyramids such as truncated quadrangular pyramids and truncated cones, a number of convex portions formed of pseudo cones having a mountain-shaped or hemispherical head, and a number of concave portions corresponding to these convex portions. It is a concave and convex pattern,
In particular, a concavo-convex pattern formed of a large number of convex portions formed of cones, mountain-shaped or hemispherical pseudo cones, and a large number of concave portions corresponding to these convex portions is preferable.

The dimensions of these embossed concavo-convex patterns are not particularly limited as long as they satisfy the above specific conditions. Generally, the interval between the protruding portions is approximately 10 to 2
It is preferably in the range of 000 μm, especially in the range of 200 to 1000 μm. In addition, the height of the convex portion is generally 5 to 5
It is preferably in the range of 00 μm, especially in the range of 20 to 100 μm. In addition, the length of the base of the convex portion is approximately 30 to 9
Those having a range of 00 μm are preferred.

In the present invention, the Abbott load curve is obtained by measuring the surface roughness of the embossed sheet using a surface roughness meter, for example, as shown in FIG. 1 of the above-mentioned JP-A-10-17338. A load length ratio [(bearing ratio tp) is obtained from the roughness curve.
= Material component (material
ial ratio) Mr], and the above-mentioned JP-A-Hei.
As shown in FIG. 2 of Japanese Patent Application Publication No. 0-17338, the load length ratio is represented on the horizontal axis, and the cutting level is represented on the vertical axis. Distribution.

Here, the load length ratio is obtained by extracting the roughness curve from the roughness curve in the direction of the average line by an evaluation length (lm), and converting the roughness curve of the extracted portion to a cutting level (p) parallel to the peak line.
sum (load length) (b ₁ + b) of the cutting lengths obtained when cutting at the profile section level
₂ + b _i ... B _n ) to the evaluation length (lm) in percentage. The cutting level is set such that the peak line of the roughness curve has a cutting level of 0% and the bottom line of the roughness curve has a cutting level of 100% (DIN 4762 and 47).
76).

In the present invention, the Abbott load curve two-dimensionally represents the average shape of the emboss. For example, as shown in FIG. (Profile section
It is expressed as a material component (Mr) as a function of n line position and is divided into three regions (Rk, Rpk, Rvk). Here, Rk (μm) is the central region of roughness, and Rpk (μm)
m) represents a converted peak height (average height of a peak protruding from the central region), Rvk (μm) represents a converted valley depth (average depth of a valley portion falling from the central region), and Mr1 (% )
Represents a material component (ratio of a peak portion), and Mr2 (%) represents a material component (ratio of a portion excluding a valley portion) (DIN
4762 and 4776).

The ten-point average roughness Rz (μm) is DIN
The arithmetic average roughness Ra (μm) is D
It is defined in IN 4762. Further, these ten-point average roughness Rz and arithmetic average roughness Ra are defined by JIS B 0
601 and is widely known to those skilled in the art as a parameter of the surface roughness of the emboss, and therefore, the description thereof is omitted.

In order to measure the parameters of the surface roughness of the emboss (Rz, Ra, Rvk, Mr2, etc.), for example, Feinpuff Perthen Gm, Germany
bH surface roughness meter (trade name: Perthomete)
r S3P) and this Perthometer S3P
Specification surface shape analyzer (trade name: SAS-2010,
The measurement can be easily performed by using Meishin Koki Co., Ltd.).

In such an Abbott load curve, R
vk (converted valley depth, that is, the average depth of the valley portion falling from the center region) is an air passage in the pre-compression bonding step between the glass plate and the intermediate film, and air is released during degassing. There is a close relationship with ease. Further, Mr2 (the material component, that is, the ratio of the portion excluding the valley portion) is not only a resistance to the movement of air, but also has a close relationship with the crushability of the emboss at the time of the preliminary pressure bonding.

Then, as a result of various studies, it was found that the surface roughness of at least one side of the emboss was 0 <Rvk / Rz ≦ 0.25,
It has been found that if Mr2 ≧ 90% and Ra = 5.0-7.0 μm are satisfied, degassing during pre-compression bonding is excellent (the invention according to claim 1).

That is, when Rvk / Rz exceeds 0.25, the depth of the concave portion becomes very deep, and air is easily trapped in this portion during degassing, and Rvk / Rz becomes zero.
Is difficult to form in practice and is not preferred because it is locally degassed. In addition, Mr2 is 90%
Below, the width of the concave portion becomes very wide, a large amount of air tends to remain in this portion, and the convex portion is easily crushed before reaching the pre-crimping condition. Degassing becomes insufficient.

Ra is an index representing the center line roughness of the emboss, and is closely related to the crushability of the emboss during pre-compression bonding. When the Ra is less than 5.0 μm, the roughness of the emboss is reduced. Even under severe conditions, sufficient deaeration is performed by the handling deaeration method, but sufficient deaeration may not be performed by the reduced pressure deaeration method due to a preceding seal. Conversely, when Ra is less than 7.0 μm, the roughness of the emboss becomes large, and even under severe conditions, sufficient deaeration is performed by the reduced pressure deaeration method. It may not be performed sufficiently, and air may enter between the glass plate and the intermediate film at the time of air pressurization in the subsequent main pressure bonding step in the autoclave.

Further, in the present invention, the plasticized polyvinyl
Plasticized polyvinyl acetate represented by nilbutyral resin
When using an interlayer made of tar resin,
In addition to the specific value conditions, the creep modulus of this interlayer
30-40 g / cm at 40 ° C ^Two7 to 14 g / at 60 ° C.
cm^Two2 to 5 g / cm at 80 ° C^TwoAny one of
One that satisfies at least one is excellent in deaeration during pre-compression bonding
(The invention according to claim 2).

That is, when an intermediate film made of a plasticized polyvinyl acetal resin is used, the vacuum degassing method generally involves sandwiching the intermediate film between two transparent inorganic glass plates,
This laminate is put in a rubber bag, and the rubber bag is connected to an exhaust system, and the temperature is increased while reducing the pressure by applying a vacuum of about -400 to -750 mmHg (absolute pressure: 360 to 10 mmHg). A crimping method is adopted. In the handling deaeration method, generally, an interlayer is sandwiched between two transparent inorganic glass plates, and the laminate is passed through a nip roll, for example, at a pressure of about ^{2 to} 10 kg / cm ² and a temperature of about 50 to 80 ° C. A method of pre-press bonding while degassing under the conditions is adopted.

In this case, the ease with which air is released during deaeration in the pre-compression bonding step is closely related to the volume of the concave portion of the emboss. It has a close relationship with the volume of the part, and further has a close relationship with the thermal properties such as the creep modulus of the interlayer film at the preheating temperature (about 40 to 100 ° C.).

Therefore, as a result of various studies, the creep elastic modulus of the interlayer film at 40 ° C. is 30 to 40 g in both cases of degassing by the reduced pressure degassing method and degassing by the handling degassing method.
/ Cm ² , 7 to 14 g / cm ² at 60 ° C., 2 to 80 ° C.
Of 5 g / cm ² , those satisfying any one or more are preferable, and those satisfying all three creep elastic moduli have been found to be optimal in terms of deaeration during pre-compression bonding.

Here, the creep modulus of the interlayer film is determined by JI
It is measured according to S K 7115 (test method for tensile creep of plastic). However, the test piece was a No. 2 type test piece, and the test load was 154 g at 40 ° C. and 60 ° C.
Is 80 g in the case of, and 20 g in the case of 80 ° C.

The blocking between interlayer films depends on the number of interlayer films to be stacked during storage. Usually, the weight of the interlayer film may be from 500 to 1000 sheets. , The intermediate film is formed under the above-mentioned specific condition (0 <
Rvk / Rz≤0.25, Mr2≥90%, Ra = 5.0-5.0
7.0 μm), it was found that the blocking resistance was good and the handling operation during storage and when the interlayer was sandwiched between glass plates was easy.

In the intermediate film of the present invention, it is preferable that both surfaces have the above-mentioned specific surface roughness, but only one surface has the above-mentioned specific surface roughness and the other surface has the conventional surface roughness. May be formed with an embossment formed of fine irregularities. Thus, the interlayer film for laminated glass of the present invention is obtained.

In order to produce a laminated glass using the interlayer film of the present invention, pre-compression bonding and main compression bonding are performed in the same manner as in a conventional method for producing laminated glass. For example, when an intermediate film made of a plasticized polyvinyl butyral resin sheet is used, specifically, pre-compression bonding and main compression bonding are performed as follows.

That is, in the pre-compression bonding, an interlayer is sandwiched between two transparent inorganic glass plates, and the laminate is passed through a nip roll, for example, under the conditions of a pressure of about ^{2 to} 10 kg / cm ² and a temperature of about 50 to 80 ° C. Preliminary pressure bonding while handling and degassing (handling degassing method), or placing the above-mentioned laminate in a rubber bag, connecting the rubber bag to the exhaust system, and approx.
A method (vacuum degassing method) is adopted in which the temperature is increased while suction and pressure is reduced to 750 mmHg vacuum (absolute pressure: 360 to 10 mmHg) and pre-compression bonding is performed at about 50 to 100 ° C.

Next, the pre-pressed laminate is used in a conventional manner by using an autoclave or a press.
Temperature of about 120-150 ° C, about 10-15 kg / cm ²
This pressure is applied. Thus, the laminated glass of the present invention is manufactured.

As the glass plate, not only an inorganic glass plate but also an organic glass plate such as a polycarbonate plate and a polymethyl methacrylate plate can be used. The laminated structure of the laminated glass may be not only a three-layer structure of a glass plate / interlayer / glass plate, but also a multilayer structure such as a glass plate / interlayer / glass plate / interlayer / glass plate. it can.

[0040]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples and comparative examples of the present invention will be described below. (Examples 1 to 5 and Comparative Examples 1 to 5) An engraving mill (mother mill) for forming an emboss is pressed against the surface of a metal roll, and the metal roll and the engraving mill are rotated, whereby the concavo-convex pattern of the engraving mill is changed to a metal roll. After that, the engraving mill is shifted in the axial direction of the metal roll by the arrangement unit of the concavo-convex pattern in order, and by the same operation as above, the concavo-convex pattern of the engraving mill is transferred to the metal roll, and the mountain-shaped concavo-convex pattern is formed. An irregularly formed embossing roll was produced.

In this case, ten sets of embossing rolls having different irregularities (the embossing rolls 5 used in Examples 1 to 5) were used.
And embossing rolls used in Comparative Examples 1 to 5) were prepared and prepared.

On the other hand, 100 parts by weight of a polyvinyl butyral resin (average degree of polymerization: 1700, residual acetyl group: 1 mol%, butyralization degree: 65 mol%), 40 parts by weight of triethylene glycol-di-2-ethyl butyrate as a plasticizer And 0.2 parts by weight of magnesium acetate as an adhesive force adjuster, and melt-knead the mixture with an extruder and extrude it into a sheet from an extrusion die to form a plasticized polyvinyl butyral sheet having a thickness of 0.76 mm. did.

Using the embossing rolls and the plasticized polyvinyl butyral sheet of each of the above sets, 10 types of embossed irregularities formed irregularly on both surfaces of the plasticized polyvinyl butyral sheet and embosses formed of fine irregularities were formed ( (Five types of Examples and five types of Comparative Examples) were manufactured.

The embossed surface roughness parameters (Rz, Ra, Rvk, Mr2) and creep modulus of the laminated glass interlayer films obtained in each of the above Examples and Examples were measured by the following methods. . Further, a laminated glass was produced using these intermediate films, and a baking test was performed on these laminated glasses by the following method to evaluate the deaeration in the preliminary pressure bonding step. The results are summarized in Tables 1 and 2.

(1) Measurement of Emboss Surface Roughness Parameter Feinpuff Perthen GmbH, Germany
Surface roughness meter (trade name: Perthometer)
S3P) and DIN 4768 and DIN 476 using a surface shape analyzer (trade name: SAS-2010, manufactured by Meishin Koki Co., Ltd.) of this Perthometer S3P specification.
2 and DIN 4776, the Rz (μ
m), Ra (μm), Rvk (μm), and Mr2 (%) were measured. These values are automatically printed out in a chart.

(2) Measurement of Creep Modulus of Intermediate Film According to JIS K 7115, a No. 2 type test piece was used. The test load was 154 g at 40 ° C. and 8 at 60 ° C.
0 g and 20 g at 80 ° C.

(3) Bake test Pre-compression bonding was performed by the following method (handling deaeration method and reduced-pressure deaeration method), and then final compression bonding was performed to produce a laminated glass.

(A) Handling and deaeration method The interlayer film is made of two transparent float glass plates (length 30 cm ×
30 cm wide x 3 mm thick), cut off the protruding part, and in a heating oven, the laminated body thus obtained was heated at a temperature of 60 ° C.
Heating was performed to 70 ° C. and 80 ° C., and then pre-press bonding was performed by passing through a nip roll (air cylinder pressure 3.5 kg / cm ² , linear velocity 10 m / min).

(B) Vacuum degassing method The interlayer film is formed of two transparent float glass plates (length 30 cm ×
(Weight 30 cm × thickness 3 mm), cut off the protruding part, transfer the thus obtained laminate into a rubber bag, connect the rubber bag to a suction decompression system, and heat at the outside air heating temperature and at the same time −600 mmHg (Absolute pressure 160m
The pressure was maintained for 10 minutes under a reduced pressure of mHg), and the laminate was heated so that the temperature (preliminary pressure temperature) became 70 ° C., 80 ° C., and 100 ° C., respectively, and then returned to the atmospheric pressure to complete the preliminary pressure bonding.

The thus obtained laminate was kept in an autoclave at a temperature of 140 ° C. and a pressure of 13 kg / cm ² for 10 minutes, and then the temperature was lowered to 50 ° C. and returned to the atmospheric pressure to complete the final pressure bonding. Thus, a laminated glass was produced.

The laminated glass was heated in an oven at 145 ° C. for 2 hours assuming severe conditions, taken out of the oven and cooled for 3 hours, and the number of foams (bubbles) generated in the laminated glass was examined. The temper was evaluated. The number of test is 1
00 sheets. The smaller the number of foams, the better the deaeration.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

As described above, in the interlayer film for laminated glass in which the embossment composed of fine irregularities is formed on both sides of the thermoplastic resin sheet, the surface roughness of at least one side of the embossment is described in detail in the text. , 0 <Rvk / Rz ≦ 0.
25, by setting so as to satisfy Mr2 ≧ 90% and Ra = 5.0 to 7.0 μm, it is excellent in blocking property during storage and handling workability when an intermediate film is sandwiched between glass plates, and a pre-press bonding step. Thus, it is possible to obtain an interlayer film for a laminated glass and a laminated glass having excellent degassing properties in the present invention (the invention according to claims 1 and 3).

In the interlayer film for laminated glass as described above, particularly, the interlayer film is made of a plasticized polyvinyl acetal resin, and the creep elasticity of this interlayer film is 30 to 40 g / cm ² at 40 ° C. and 60 ° C. 7-14 g / cm ² ,
By setting so as to satisfy at least one of ² to 5 g / cm ² at 80 ° C., it is excellent in blocking property during storage and handling workability when an interlayer film is sandwiched between glass plates, and pre-press bonding. It is possible to obtain an interlayer film for laminated glass and a laminated glass which are more excellent in degassing properties in the process (the invention according to claims 2 and 3).

Therefore, when a laminated glass is manufactured using the interlayer film of the present invention, even when a laminated glass having a large area or a laminated glass having a large curvature is manufactured, or when the productivity of the laminated glass is increased, the laminated glass can be removed. Is performed sufficiently, the layer of the interlayer is satisfactorily smoothed along the surface of the glass plate, particularly excellent in transparency, and does not cause foaming even when used under severe conditions. A laminated glass of good quality can be produced with good workability, with good adhesion to the interlayer and excellent transparency.

Claims (3)

[Claims] 1. An intermediate film for laminated glass having an embossment having fine irregularities formed on both surfaces of a thermoplastic resin sheet, wherein at least one surface has an emboss surface roughness of 0 <.
Rvk / Rz ≦ 0.25, Mr2 ≧ 90%, and R
a = 5.0-7.0 μm. Here, Rz (μm) is DIN 4
768 represents the ten-point average roughness specified in 768, and Rvk is DIN
Represents the converted valley depth (μm) obtained from the Abbott load curves defined in 4762 and 4776, and Mr 2 represents the material component (%) obtained from the Abbott load curves. R
a (μm) represents the arithmetic average roughness specified in DIN 4762. 2. The intermediate film is made of a plasticized polyvinyl acetal resin, and has a creep modulus of 3 ° C. at 40 ° C.
0~40g / cm ^2, at 60 ℃ 7~14g / cm ^2, 8
^2. The interlayer film for laminated glass according to claim 1, wherein at least one of ² to 5 g / cm ² is satisfied at 0 ° C. 3. 3. A laminated glass comprising the interlayer film for laminated glass according to claim 1 or 2.