JPS60208241A - Intermediate film for safety glass - 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 11) Industrial Application Field 1 relates to an interlayer film for laminated glass widely used in various transportation vehicles such as automobiles and aircraft, and windows of buildings.

(2) Prior art In order to manufacture laminated glass, generally a method is used in which two sheets of laminated glass are plasticized with polyvinylgtyral and then subjected to main compression bonding in an autoclave. Conventionally, medium rfI
In order to improve the deaeration property in the preliminary ejection process and to prevent the sticking of the medium 11 [1M], the J film is coated with, for example, KrIH as shown in Mochisu Old Publication No. 57-150532, Both sides were provided with unevenness of various shapes (L<f1), but the interlayer film t-t i! had excellent degassing and anti-blocking properties. The current situation is that it is not being used.

(3) Purpose of the Invention It is an object of the invention to provide an interlayer film for laminated glass that has improved blocking properties and excessive adhesion to glass, etc., and has excellent degassing properties during the pressure bonding process.

(4) Structure of the Invention The gist of the present invention is that finer unevenness is formed on the surface of a large number of coarse unevenness provided on at least one side #/c, and the coarse unevenness is within the range of about 20071 to 800μ. Intermediate It! for laminated glass characterized by having a constant pitch at! JK exists.

Examples of materials used for the interlayer film of the present invention include polyvinyl butyral, polyurethane, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-vinyl alcohol copolymer, ethylene-methyl methacrylate copolymer, etc. In particular, plasticized polyvinyl butyral is difficult to use.

The shape of the coarse irregularities in the misfire 91 is not particularly limited, and may be a truncated triangular pyramid, a square pyramid, a truncated cone, a triangular pyramid, a square pyramid, or a circular shape.

It is preferable that these be provided continuously, but they may be provided in one continuous manner.

However, in the case of grooves, if the direction of degassing during preliminary crimping is set perpendicular to the grooves, the empty 91N flow path will be closed, so care must be taken to make the direction of degassing parallel to the grooves.

In FIG. 1, which simulates an example of the surface roughness curve of the interlayer film of the present invention, 1 is a coarse concave portion, 2Vi is a coarse convex portion,
There are three fine irregularities provided on each of these, and the interlayer film surface has double irregularities as a whole.

The coarse irregularities have a constant pitch (for example, represented as W in FIG. 1).

This is because if the pitch of the coarse irregularities is irregular, the air flow passages formed in the assembly may be affected by the air flow path formed in the assembly when the interlayer film is sandwiched between the glass plates and the assembly is degassed in the preliminary crimping process. This is because air tends to be insufficiently removed, making it difficult to manufacture laminated glass from which air bubbles have been completely removed. If this pitch is too large, it becomes difficult to improve the interlayer film's tensile resistance, so the pitch is set to about 200 to 800, +1, preferably 300 to 600/I. Although variations in the pitch of many interlayer films that can actually be manufactured are unavoidable, tF can be tolerated if the variations in the same interlayer film are within ±20% of the set pitch.

Although the surface roughness of the large irregularities mentioned above is not particularly limited, it is generally 20 to 80, preferably 30 to 60/I in 10 point average roughness measured in accordance with %15OR468. In other words, in Fig. 1, if we consider the area divided by the standard length, we can calculate the average height of the five peaks from the highest peak 21 to the fifth highest peak 25, and the deepest valley 11.
The difference from the average height of the five valleys from 15 to the fifth deepest valley 15 is defined as the 10-point average roughness H.

Therefore, in FIG. 1, if HVi is the height of the peak or valley measured from the base line A, Hi (an integer of pt Vil -10) is calculated by the following equation.

Note that the reference length LVi is not particularly limited, but is usually set to 8%.

The surface roughness of the fine irregularities formed on the coarse irregularities is generally 1 to 15p, preferably 3 to 10p. However, an appropriate value within the above range is generally selected depending on the material, physical properties, degree of roughness, etc. of the film, and the blocking resistance of the interlayer film is improved by reducing the contact area between the films. urge When the average height of the coarse irregularities is relatively small, it is preferable to make the surface roughness of the fine irregularities relatively small.

These fine irregularities impart excellent blocking resistance to the interlayer film, and as a result, the glass and the interlayer film do not unfavorably adhere to each other during preliminary pressure bonding, preventing air from being trapped. The interlayer film has excellent degassing properties.1. Examples of methods for manufacturing the interlayer film having the double uneven shape of the present invention include embossing roll U1, calender roll method, 74 type extrusion method, etc. Can be mentioned.

The interlayer film of the present invention may contain/adhere to various additives such as a Vi ultraviolet absorber, an anti-oxidation pickpocket, a colorant, and an adhesion regulator, and the thickness of the interlayer film may be 0.1 ~2
A range of 0% is suitable for various uses.

By sandwiching the thermoplastic M4 resin film, whose surface is coated with metal or metal compound and has been given functional properties such as heat insulation and conductivity, with the middle part of the wood, we can create a functional structure. It is also possible to obtain interrogation.

In order to manufacture laminated glass using unexploded 1-width (υ membrane), it is usually made of an inorganic glass plate and an inorganic glass plate, or an inorganic glass plate and a translucent hard resin such as polycarbonate fat absorbent or acrylic resin. An interlayer film is inserted between the organic glass plate, and the layer is placed in a rubber bag and degassed under reduced pressure. Put it in an autoclave 8
Transparent laminated glass is obtained by checking the actual pressure under high temperature and pressure.

(6) Effects of the invention Middle circumference M of the present invention! Since the large number of coarse irregularities provided on at least one side have a constant pitch of approximately 200 fi to 800/l, the assembly is The air inside can be sufficiently degassed, so the present invention is intermediate! 2! This makes it possible to obtain laminated glass without bubbles that can be observed with the naked eye.

Since the medium film of the present invention has fine irregularities formed on the surface of the coarse irregularities, blocking properties and excessive adhesion to glass plates are small, improving the workability of laminated vitrification and making it easier to use during storage. The number of sheets stacked increases.

Furthermore, since the surface of the interlayer film #'i of the present invention is formed with the dQ-double uneven shape, the convex portions are easily crushed during preliminary press-bonding, so that the line speed of the preliminary press-bond process can be increased.

(6) In the following Examples, the blocking property of the interlayer film and the foaming property of laminated glass by heating were measured using the following method.

(i) Cut the blocking interlayer film into 1100m x 25 pieces, stack 2 sheets, put 2 to 9 layers on top of it, leave it at room temperature for 24 hours,
In the tensile test, 180° peeling was performed at a speed of 200°.
The blocking property of the sample was shown by the average value of the peeling force obtained at that time (3 for 8 cycles).

A value of 7 means that the higher the value, the greater the adhesive force between the films, and therefore the worse the workability during laminated glass production.

■ The foamable interlayer film was sandwiched between two inorganic glass films, and the resulting assembly was passed through a heating oven to raise the surface temperature of the heated laminate to 70°C, 80°C, and 90°C. After adjustment, the material was degassed by the ironing method using nip rolls, and preliminary crimping was performed.

Then, the laminate was placed in a pressurizer at a pressure of 13 Kmffl.
After pressurizing and heating at a temperature of 130° C., the pressure was gradually returned to 50° C. to produce a laminated glass. Ten sheets of laminated glass were heated in a gear oven at 120° C. for 2 hours, and the number of sheets of laminated glass with bubbles generated was counted.

Example 1 An embossing roll was used to create double irregularities on both surfaces of a plasticized polyvinyl gucciol medium IN film containing a xoOWfi part of polyvinyl gucciral and a 40-ply part of triethylene glycol-di-2-ethyl guccilate. Formed.

The shape of the coarse irregularities is a continuous triangular pyramid shape, the 10-point average J-sake is 60, II, the pitch is #-t400/l,
The surface roughness of fine irregularities was 10 tones.

The blocking properties of this film at room temperature and the foaming properties of the obtained laminated glass were as shown in Table 1.

Examples 2 and 3 In the same manner as in Example 1, intermediate films having double unevenness formed on the surface were obtained. The shape of the unevenness and each physical property (Fi) are shown in Table 1.

Comparative Examples 1 and 2 In the same manner as in Example 1, an embossing roll was used to obtain interlayer films having irregularities formed on the surface.

However, as shown in Table 1, the shape of the unevenness was free of minute unevenness. The blocking properties of this film and the foaming properties of laminated glass are the best! ! It was as follows.

Table 1 *- represents 70°C, B: 80°C, and C1j: 90°C.

[Brief explanation of the drawing]

FIG. 1 is a diagram schematically showing an example of a surface roughness curve of an uninvented intermediate model. Explanation of symbols 1. Coarse concave portion, 2.. Coarse convex portion, 3.. Fine unevenness, W... Pitch 11 figure

Claims (1)

[Claims] L There are no fine irregularities formed on the surface of the large number of coarse irregularities provided on at least one side, and the coarse irregularities are approximately 20,071 to 800 mm. Intermediate a for laminated glass characterized by having a constant pitch within the range of II! llI.