JP2000296555A - Embossing roll and production of intermediate film for embossed glass laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an embossing roll improving the mutual blocking resistance of a film at a time of keeping, handling workability at a time when glass plates and an intermediate film are superposed on upon another and degassing properties at a time of lamination processing and used in the production of the intermediate film for an embossed glass laminate generating no perspective strain and a method for producing the intermediate film for the embossed glass laminate. SOLUTION: An embossing roll is obtained by forming a large number of uneven embosses on the surface of a metal roll by a blast treatment method or a carving mill method and pressing a grinding wheel to the embossed surface of the metal roll in a nonrotatable fixed state and semi-polishing the metal roll while rotating the same. This embossing roll is used to apply embossing processing to the surface of the intermediate film for the glass laminate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an embossing roll,
In particular, the present invention relates to an embossing roll used for producing an interlayer film for laminated glass with embossing and a method for producing an interlayer film for laminated glass with embossing.

[0002]

2. Description of the Related Art An embossed thermoplastic resin sheet in which a large number of fine irregularities (embosses) are formed on the surface of a thermoplastic resin sheet is widely used for interlayer films for laminated glass and other uses.

[0003] For example, the surface of an interlayer film for laminated glass is used to improve the anti-blocking properties of the films during storage, the handling workability when laminating a glass plate and an interlayer, and the degassing property during laminating. In general, a large number of irregularities (embosses) are formed using an embossing roll.

The embossing roll used for forming the emboss is generally formed by a method of blasting the surface of the metal roll, a method of etching the surface of the metal roll, a method of engraving the surface of the metal roll, and an engraving on the surface of the metal roll. It is manufactured by a method of sequentially transferring irregularities of a mill (mother mill).

In this case, many excessive peaks (projections having irregular heights) are formed on the embossed surface of the embossing roll.
Occurs, and when there are many such excessive peaks, they are transferred to the surface of the intermediate film as many depressions.

[0006] If the surface of the interlayer film for laminated glass has many depressions as described above, it becomes difficult for air to flow, which causes a problem in deaeration during laminating. In particular, when deaeration is performed by a handling roll method rather than by a vacuum bag method, air escape is poor, and foaming and sealing failure due to air accumulation in the obtained laminated glass occur.

Japanese Patent Publication No. 54-21209 discloses that a surface of a metal roll is blasted by spraying a blasting agent such as aluminum oxide and then blasted using glass beads or a conventional wrapping material is used. By polishing the embossed surface layer using
A method for obtaining an embossing roll is disclosed.

[0008]

In the above conventional method, when the embossed surface layer is polished by blasting using glass beads, it is necessary to make the particle size of the glass beads relatively large. If the particle size is increased, undulation occurs on the embossed surface to be formed and is transferred to the surface of the intermediate film.Therefore, a minute difference in thickness occurs due to the undulation of the embossment. In the laminated glass obtained in this way, a see-through distortion occurs in which the image is distorted.

On the other hand, when the embossed surface layer is polished by using a grinding wheel as a conventional lapping material, the polishing is performed while rotating the metal roll by pressing the surface of the emboss while rotating the grinding wheel. Is common.
In such a method in which the grinding wheel is rotated and polished, the frictional resistance is increased, so that a feed mark or chatter mark due to the grinding wheel appears and is transferred to the surface of the intermediate film. In the laminated glass thus obtained, minute disturbance occurs due to feed marks and chatter marks at the interface of the intermediate film, and perspective distortion occurs.

The present invention solves the above problems,
Its purpose is to improve the embossing roll, especially the blocking resistance between the films during storage, the handling workability when laminating the glass plate and the interlayer, and the deaeration during the laminating process. An object of the present invention is to provide an embossing roll and a method for producing an interlayer film for an embossed laminated glass, which are used for producing an interlayer film for an embossed laminated glass which does not occur.

[0011]

In order to achieve the above object, according to the first aspect of the present invention, after forming an emboss having a large number of irregularities on a surface of a metal roll by a blasting method or an engraving mill method, the embossing is performed. An embossing roll is provided in which a grinding wheel is pressed against a surface portion of the embossment without being rotated, and is semi-polished while rotating the metal roll.

According to a second aspect of the present invention, there is provided an embossing roll according to the first aspect, which is used for producing an interlayer film for an embossed laminated glass.

According to a third aspect of the present invention, there is provided a method for manufacturing an interlayer film for an embossed laminated glass, wherein the surface of the interlayer film for a laminated glass is embossed by using the embossing roll according to the first aspect. A method is provided.

In the present invention, a mirror-polished chilled iron roll or the like is preferably used as the metal roll. An emboss having many irregularities is formed on the surface of such a metal roll. As the method of forming the emboss,
A blast treatment method in which a blasting agent is sprayed on the surface of the metal roll, or an engraving mill method in which irregularities of an engraving mill (mother mill) are sequentially transferred to the surface of the metal roll are employed. The blasting method is preferred in that unevenness can be obtained.

In the blasting method, aluminum oxide (alumina) or a blasting agent that crushes hard spheres is mainly used as a blasting agent. However, when crushing the hard spheres, piercing or rusting may occur on the roll surface. Therefore, it is preferable to use aluminum oxide. The particle size of aluminum oxide is generally from JIS # 20
No. # 120, preferably # 30 to # 80 is used, and the discharge pressure is generally 4 to 15 kg / cm ² , and blasting is performed until a desired surface roughness is obtained.

Thereafter, the grinding wheel is pressed against the surface of the emboss without rotating, and is semi-polished while rotating the metal roll. Here, the semi-polishing means that only the surface portions of a large number of irregularities formed on the surface of the metal roll are uniformly ground and removed by polishing.

As the grinding wheel, generally, JIS standard No. 200 to No. 2000, preferably No. 400 to No.
No. 1000 aluminum oxide (alumina) or silicon carbide is preferably used. In addition, sandpaper is also included in a grinding wheel. The pressing force of the grinding wheel is generally 0.2 to
It is 10 kg / cm ² .

The degree of semi-polishing (semi-polishing rate) is generally determined by a load length ratio (tp p) specified in JIS B0601.
) Is convenient. That is, a part of the roughness curve of the embossed roll after semi-polishing is extracted by the reference length in the average line direction, and the ratio of the sum of the cutting lengths at the level parallel to the peak line of the roughness curve of the extracted part to the reference length. However, semi-polishing is performed so as to be 10 to 70%, preferably 30 to 50%.

After the semi-polishing, metal plating such as chromium, nickel, and zinc is applied by a conventional method along the roughness and shape of the emboss. Metal plating may be either electroplating or chemical plating, but in particular, chemical plating is
This is preferable in that a plated layer having a smooth and uniform thickness can be formed along the roughness and shape of the emboss. For chemical plating, for example, a plating bath (so-called KAN) composed of a metal salt (such as nickel sulfate or nickel chloride), a reducing agent (such as sodium phosphite) and a buffering agent (such as sodium acetate) is used.
An IGEN plating bath is preferably used.

The thickness of the metal plating is preferably thin in order to maintain the roughness and shape of the emboss, while it is preferably thick in terms of chemical resistance and rust prevention.
20 μm is preferred. The embossing roughness of the finally obtained embossing roll is determined by metal plating JIS B 060.
20 to 50 μm in ten-point average roughness (Rz) defined in 1.
It is preferred that

Thus, the embossing roll of the present invention is obtained. In order to manufacture an embossed thermoplastic resin sheet, particularly an interlayer film for laminated glass with laminated glass embossing, using the embossing roll of the present invention, a known method of embossing the surface of the interlayer film for laminated glass is employed. . For example, by pressing a thermoplastic resin sheet, particularly an interlayer film for laminated glass, on the surface of the embossing roll under heating, and transporting the sheet while peeling off the sheet from the embossing roll, a thermoplastic resin sheet, particularly laminated glass Embossing is applied to the surface of the intermediate film.

As the thermoplastic resin sheet, for example, various thermoplastic resin sheets such as a polyolefin sheet, a soft polyvinyl chloride sheet, a thermoplastic resin elastomer sheet, and an ABS resin sheet are used according to applications. As the interlayer film for laminated glass, for example, a known interlayer film for laminated glass made of a plasticized polyvinyl acetal resin, a polyurethane resin, an ethylene-vinyl acetate resin, an ethylene-ethyl acrylate resin, and a plasticized vinyl chloride resin. Used.

(Operation) As described above, after forming an emboss having a large number of irregularities on the surface of a metal roll by a blasting method or an engraving mill method, a semi-polishing is performed by pressing a grinding wheel on the surface of the emboss. Since the blasting process using glass beads having a relatively large particle size as in the conventional method is not performed, an excessive peak of the emboss (a protruding convex portion having an irregular height) can be uniformly formed without causing undulation on the embossed surface. Removed.

In this case, if the grinding wheel is pressed in a fixed state without rotating, and is semi-polished while rotating the metal roll, the grinding wheel (lapping material) is not rotated as in the conventional method. The size of the emboss is reduced, and the formation of a feed mark or chatter mark on the formed emboss by the grinding wheel is prevented.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples and comparative examples of the present invention are shown below. (Example 1) A mirror-polished metal roll (350 m in diameter)
A blasting agent made of # 36 aluminum oxide (alumina) was blasted at a discharge pressure of 5 kg / cm ² on the surface of a m chilled iron roll) to form an emboss having many irregularities.

Thereafter, semi-polishing was performed using a # 400 grinding wheel, followed by semi-polishing using a # 1000 grinding wheel. These semi-polishing processes apply # 400 and # 100 to the embossed surface of the metal roll.
In a state where the No. 0 cylindrical grinding wheel was fixed without rotating, the metal roll was pressed with a pressure of 5 kg / cm ² ,
This was performed while rotating at rpm.

Finally, the metal roll after the semi-polishing process is
Immerse in an ANIGEN plating bath to obtain a 14 μm thick [N
i (90% by weight) -P (10% by weight)]. Thus, two embossing rolls were produced.

Regarding the embossing roll, JIS B
10 point average roughness of emboss (Rz) based on 0601
When the arithmetic mean roughness (Ra) was measured, the ten-point mean roughness (Rz) was 40 μm, and the arithmetic mean roughness (Ra) was 5.
It was 1 μm. When the surface undulation (wave undulation) was measured, no wave undulation was observed.

In order to know the degree of semi-polishing, the above-mentioned semi-polishing rate (load length rate) tp was measured based on JIS B 0601.
Was 45%. When the surface condition of the embossing roll was observed, no feed mark or chatter mark of the grinding wheel was observed at all.

On the other hand, to 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 were added. The mixture was melt-kneaded with an extruder, extruded into a sheet from an extrusion die, and kept at 114 ° C. by temperature control. Subsequently, the sheet was passed between a pair of the upper and lower embossing rolls (embossing devices) adjusted to 130 ° C. to form an embossed laminated glass interlayer having an average thickness of 0.76 mm.

The obtained interlayer film for laminated glass with embossing was evaluated for its 60-degree specular gloss, the presence or absence of excessive dents, the slippage of the film, and the handleability of the film. The 60-degree specular gloss was 9.0%. There was no excessive depression, the sliding of the film was good, and the handleability of the film was good.

Further, in order to evaluate the degassing property, preliminary press-bonding is performed by the following method, and then main press-bonding is performed.
A laminated glass was produced.

The intermediate film is sandwiched between two transparent float glass plates (length 30 cm × width 30 cm × thickness 3 mm),
The protruding portion is cut out, and the thus obtained laminate is heated in a heating oven to a constant temperature (every 5 ° C.) in which the temperature of the laminate (preliminary compression temperature) is in the range of 50 to 90 ° C., and then the nip roll ( Air cylinder pressure 5kg
/ Cm ² , a linear velocity of 10 m / min) for pre-compression bonding.

The laminate thus obtained is held in an autoclave at a temperature of 135 ° C. and a pressure of 12 kg / cm ² for 20 minutes, and then the temperature is lowered to 50 ° C. and the pressure is returned to the atmospheric pressure to complete the final pressure bonding. Thus, nine types of laminated glass were produced.

The laminated glass was heated in an oven at 145 ° C. for 2 hours under 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 degassing was evaluated. The number of test pieces was set to 100, and the pre-pressing temperature range in which good deaeration (three or less foamed sheets in 100 pieces) was obtained was examined. As a result, at the pre-compression bonding temperature of 50 ° C., the seal was poor, and at 90 ° C., air accumulation due to the advance of the seal occurred, and the pre-compression temperature range was 55 to 85 ° C.

Further, with respect to these laminated glasses,
Perspective distortion Δα specified in JIS R 3212
When (minute) was measured, the see-through strain Δα was 2 or less, which was good. Table 1 summarizes the above results.

Example 2 A blast treatment was performed at a discharge pressure of 6 kg / cm ² using a blast agent made of # 56 aluminum oxide. Other than that, it carried out similarly to Example 1. Table 1 shows the results.

(Comparative Example 1) Semi-polishing was performed by rotating # 400 and # 1000 cylindrical grinding wheels.
Other than that, it carried out similarly to Example 1. Table 1 shows the results.

(Comparative Example 2) Instead of semi-polishing using a # 400 cylindrical grinding wheel, a blasting agent made of a steel ball having a diameter of 1.2 mm was used, and a discharge pressure of 1.5 kg / cm ² was used.
Blasted. Other than that, it carried out similarly to Example 1. Table 1 shows the results.

[0040]

[Table 1]

[0041]

As described above, in the embossing roll of the present invention, after forming an embossment having a large number of irregularities on the surface of a metal roll by a blasting method or an engraving mill method, a grinding wheel is rotated on the surface of the embossing roll. Pressing in a fixed state without making it, and semi-polishing while rotating the metal roll, without causing undulation on the embossed surface, the excessive peak of the emboss (protruding convex with irregular height) Portion) is uniformly removed, and the generation of feed marks and chatter marks caused by the grinding wheel is prevented.

Accordingly, when the embossing roll of the present invention is used to produce an interlayer film for an embossed laminated glass, particularly by embossing the surface of the interlayer film for a laminated glass, the blocking resistance of the films during storage is reduced. In addition, it is possible to improve the handling workability at the time of laminating the glass plate and the interlayer and the degassing property at the time of the laminating process, and to obtain an interlayer film for an embossed laminated glass which does not cause a perspective distortion.

Claims (3)

[Claims] After forming an embossment having a large number of irregularities on the surface of a metal roll by a blasting method or an engraving mill method, the surface of the emboss is pressed in a state in which a grinding wheel is fixed without rotating, and An embossing roll characterized by being semi-polished while rotating a metal roll. 2. The embossing roll according to claim 1, which is used for producing an interlayer film for an embossed laminated glass. 3. A method for producing an interlayer film for embossed laminated glass, comprising embossing the surface of the interlayer film for laminated glass using the embossing roll according to claim 1.