JPH04175248A - Production of interlayer for laminated glass having colored band - Google Patents

Abstract

PURPOSE:To linearly and uniformly apply a coating line by applying a volatile solvent of polyvinyl butyral(PVB) to a side of a surface of a plasticized PVB sheet for receiving an image layer of a transfer paper, placing an image layer on the coated surface and hot-pressing the laminate. CONSTITUTION:A plasticized polyvinyl butyral(PVB) sheet 1 is horizontally passed between a coating roll 2 and a sheet-transfer roll 3 from a side to the other side. The coating roll 2 is placed in a state inclining its axis relative to perpendicular direction and the transfer roll 3 has horizontal axis and is placed opposite to the coating roll 2. A volatile solvent of PVB supplied to a coating liquid transfer roll 8 is applied to a side of the surface of the sheet 1 at 10-20 deg.C and, immediately after the coating process, the coated surface is laminated with an image layer of a transfer paper 9 produced by forming an ink image layer containing a dye and/or a pigment as coloring agents on a base sheet using PVB as a binder. The laminate is passed through press rolls 7, 7 at <=40 deg.C and pressed under a pressure of 2-6kg/cm<2>. The base sheet of the transfer paper 9 is peeled off and the PVB sheet is heated at <=130 deg.C to evaporate and remove the solvent of PVB.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method for producing an interlayer film for laminated glass having a uniform coated appearance and a colored image. For more details,
Laminated glass that has a sloped interval between the coating roll for coating the interlayer film and the transport roll, allowing the coating liquid to be applied uniformly and in a straight line with no uneven coating, resulting in a good appearance as a product. The present invention relates to a method for producing an interlayer film for use.

[Prior Art and Problems to be Solved by the Invention] Sheets made of so-called plasticized PVB, which is made by blending polyvinyl butyral (hereinafter referred to as PVB) with a plasticizer to give it flexibility, have poor adhesion to glass plates. Because of its good quality, toughness, and excellent transparency, laminated glass using it as an interlayer is often used in automobile windshields and building window glasses. If a transparent light-shielding colored band is applied to part or the entire surface of the laminated glass used for such purposes, the anti-glare effect will be improved for car windshields, and for show window glasses, etc. Various methods of manufacturing laminated glass having colored bands have been studied and proposed in the past because it is expected to have an effect of preventing fading of exhibits. Conventional techniques for producing laminated glass with a colored band are broadly divided into methods of applying a colored band to the glass and methods of applying a colored band to an interlayer film. The former method of vitrification has the drawbacks that the quality of the colored band is poor, that special equipment such as a kiln is required, and that it is not suitable for mass production. As a method to avoid the above-mentioned drawbacks, a method of applying a colored band to the interlayer film has been studied, and a method of applying a colored band to a plasticized PVB sheet by a transfer method has been proposed. For example, in Japanese Patent Publication No. 5G-38152 and No. 56-45777, a transfer paper with a printed image layer provided on a transfer base sheet is overlaid on a plasticized PVB sheet, and the printed image layer is plasticized by heating and pressing. A method for transferring to a chemically modified PVB sheet is described. However, since this method employs a heating and pressurizing method, the process is complicated, there is a problem that the performance of the interlayer film deteriorates due to heating, and the cost is also relatively high, so it is not a satisfactory method. Moreover, in Japanese Patent Application No. 63-281976, plasticized PVB
In order to prevent the embossed shape of the fine irregularities on the sheet surface from being destroyed, a method is described in which a volatile polyvinyl butyral-soluble solvent is applied to the surface of a plasticized PVB sheet and transferred at a low temperature. However, even in this method, when applying the volatile PVB-soluble solvent, there were problems such as spreading of the coating solution and disorder of the coating line. The present invention has been made in view of the above-mentioned problems in the conventional technology. Therefore, the object of the present invention is to form the application line linearly.
To provide a method for producing an interlayer film for laminated glass, in which a coating solution can be uniformly and neatly applied without coating unevenness, and the product has a good appearance.

[Means and effects for solving the problem] The present inventors have conducted extensive research in order to develop a method for manufacturing an interlayer film for laminated glass having a colored band by a transfer method, which solves the problems of the above-mentioned conventional technology. As a result, if the distance between the coating roll and the conveying roll for coating the interlayer film with the PVB-soluble solvent is sloped, the coating line can be straightened and the coating can be applied uniformly and neatly without any unevenness. They discovered that it is possible to improve the appearance of a product, and have completed the present invention. The present invention uses PVB as a binder on a base sheet,
An interlayer film for laminated glass having a colored band on one side in the width direction by transferring the image layer on the surface of a plasticized PVB sheet of a transfer paper on which an image layer is formed with an ink containing dyes and/or fines as a coloring agent. A method for producing a method comprising: a) applying a coating liquid made of a volatile PVB-soluble solvent to one side of the surface of a plasticized PVB sheet to which an image layer of a transfer paper is to be transferred at a temperature of 10 to 20°C; 1 step, b) Immediately after applying the solvent, the image layer of the transfer paper is superimposed on the surface coated with the coating solution and the second step is pressurized at a temperature of 40° C. or less. C) Then, the base sheet of the transfer paper is peeled off. , said PVB
and a third step of volatilizing and removing the soluble solvent, and in the first step, the plasticized PVB sheet is arranged so that the axis thereof is tilted vertically from one side to the other side. The coating liquid supplied by the coating liquid conveying roll is passed horizontally between a pair of rolls consisting of an applied coating roll and a sheet conveyance roll disposed horizontally below and opposite the coating roll. It is characterized in that a coating liquid is applied to one side of the surface of the plasticized PVB sheet by a held coating roll. The present invention will be described in detail below. FIG. 1 is a schematic diagram of an apparatus for carrying out the invention, FIG.
The figure and FIG. 3 are a front view and a perspective view showing the relationship between the application roll and the sheet conveyance roll in FIG. 1. In the figure, 1 is a plasticized PVB sheet, 2 is an application roll, and 3 is a sheet conveyance roll. The application roll 2 is the second
As shown in the figure and FIG. 3, the gravure cylinder 8 has a gravure plate formed on one side, and its axis is directed from the gravure cylinder side to the other side with respect to the sheet conveyance roll 3. They are vertically inclined and arranged to face each other so as to be gradually spaced apart from each other. A coating liquid conveying roll 5 supports and conveys the volatile PVB-soluble solvent stored in the coating liquid pan 6, and supplies it to the surface of the coating roll 2. In the first step of the invention, the plasticized PVB sheet 1 is passed horizontally between an applicator roll 2 and a sheet transport roll 3, thereby dissolving the volatile PVB supplied onto the gravure cylinder 8 of the applicator roll. A solvent is applied to one side of the surface of the plasticized PVB sheet. During printing, the application roll 2 is provided facing the sheet conveyance roll 3 with its axis tilted vertically as described above, so that the application liquid does not protrude to the outside of the gravure cylinder. The application line becomes straight and the appearance can be improved. In the present invention, when applying a solvent to the entire surface of the coating roll from the coating liquid conveying roll, excess coating liquid is removed from areas other than the gravure body of the coating roll 2 to prevent the coating liquid from spreading. For this purpose, the scraping blade 4 can be provided so as to come into contact with the area where the gravure plate is not formed. Further, it is preferable that the applicator roll is arranged such that the inclination of its axis can be adjusted, and the inclination adjustment angle α is tan
If the value of α is too large, the conveyance of the plasticized PVB sheet will become unstable, and if it is too small, the conveyance of the plasticized PVB sheet will become impossible and cause problems.
Xl0-5~I Xl0-', preferably tanα=
7.5 Set it to about Xl0-5. The coating temperature in the first step needs to be in the range of 10 to 20°C. If the coating temperature is below 10°C, the plasticized PVB sheet will become hard and the surface cannot be uniformly wetted, and if it exceeds 20°C, the plasticized PVB sheet will wrap around the coating roll, impeding the flow of the sheet. Furthermore, the amount of the coating liquid to be applied can be appropriately set by adjusting the interval between the application roll and the sheet conveyance roll, depending on the thickness of the plasticized PVB sheet. In the second step, after applying the solvent to the plasticized PVB sheet in the first step, the colored image layer of the transfer paper 9 is immediately superimposed on the solvent-coated surface, and the sheet is heated at 40°C in a pressure transfer section.
Pressure transfer is performed by passing through a pair of pressure rolls 7.7 under the following temperature conditions. At this time, if the temperature at the time of transfer is higher than 40°C, the embossed shape of fine irregularities formed on the surface of the plasticized PVB sheet will be destroyed, so it is necessary to keep the temperature at 40°C or lower. A preferred temperature range is 10-30°C, more preferably 15-35°C. Pressure conditions during transfer are not particularly limited, but are appropriately selected from a range that allows the transfer paper and the plasticized PVB sheet to be brought into close contact and does not destroy the embossed shape on the surface of the plasticized PVB sheet under the above transfer temperature conditions. do it. Suitable pressure conditions during transfer are in the range of 2 to 6 kg/cm2, more preferably in the range of 3 to 5 kg/Cl112. In the third step, the PVB-soluble solvent applied before the transfer is removed by volatilization from the plasticized PVB sheet after the transfer. If the PVB-soluble solvent is not sufficiently volatilized and removed, the plasticized PVB sheet will become sticky and difficult to handle. Foaming may occur between the laminated glass and the membrane, and intervening air may not be sufficiently removed, making it impossible to obtain a satisfactory laminated glass. In order to sufficiently volatilize and remove the above-mentioned solvent, there is no need to use a special method, and ordinary drying means may be used. For example, it may be evaporated in a dryer set at 130°C or lower, preferably 100°C or lower. Drying temperature is 100
If the temperature exceeds 130°C, there is a risk that the plasticized PVB sheet will shrink or warp, and if the temperature exceeds 130°C, this tendency will become noticeable, so it is preferable to set the temperature within the above range. Next, each material used in the present invention will be explained. The plasticized PVB sheet used in the present invention is not particularly limited as long as it is generally used as an interlayer film for laminated glass. Such an interlayer film has a degree of butyralization of 60 to 75 mol% and an average degree of polymerization of 800 to 3.
000 PVB, 20 to 50 parts by weight of plasticizers such as diethyl phthalate, tricresyl phosphate, di-n-hexyl adipate, triethylene glycol di(2-ethyl butyrate) are blended. Made from plasticized PVB as a raw material and produced by a conventional film forming method such as an embossing method or a calendar roll method.
Examples include those having a thickness of about 200 to 1000 μm. Such an interlayer film is embossed with fine irregularities of 20 to 30 μm on average in order to facilitate the removal of air during pressure bonding with glass. The volatile PVB-dissolving solvent used in the present invention is capable of dissolving PVB at a temperature that does not alter or deform the plasticized PVB sheet, e.g.
It is not particularly limited as long as it can be volatilized and removed at a temperature of 0.000°C or less, preferably 100°C or less. As the volatile PVE-soluble solvent, a single soluble solvent or a mixed solvent of a plurality of soluble solvents can be used.
A mixed solvent containing a solvent with low solubility can also be used. Examples of soluble solvents include methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol,
Butyl alcohol, isobutyl alcohol, 5ee-butyl alcohol, tert-butyl alcohol, pentyl alcohol, IeN-pentyl alcohol, amyl alcohol, isoamyl alcohol, 5ec-amyl alcohol, tert-amyl alcohol, diethyl carbinol, hexyl alcohol, methyl amyl alcohol Alcohols such as , ethyl butyl alcohol, cyclohexanol, methylcyclohexanol, trimethylcyclohexanol, benzyl alcohol, methylphenyl alcohol; methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl butyl ketone, ethyl butyl ketone, 2-methyl-4- Pentanone, 2-ethyl-4-pentanone, 2-pentanone, 3-pentanone,
Examples include ketones such as cyclohexanone, methylcyclohexanone, acetone, acetophenone, and acetylacetone; ethers such as isopropyl ether, ethyl butyl ether, butyl ether, amyl ether, dioxane, dimethyldioxane, trioxane, tetrahydrofuran, and tetrahydropyran. In addition, examples of solvents with low solubility include hexane, isohexane, methylpentane, heptane, isohbutane, octane, isooctapenonane, decane, cyclopentane,
Hydrocarbons such as methylcyclopentane, cyclohexane, methylcyclohexane, benzene, toluene, xylene, amylbenzene, cyamylbenzene, amyltoluene, diphenylethane, ethylbenzene, diethylbenzene, triethylbenzene, cumene; methyl acetate, ethyl acetate, propyl acetate , isopropyl acetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, and other esters. The volatile PVB-soluble solvent used in the present invention is preferably a combination of the above-mentioned soluble solvent and a low-solubility solvent, or a combination of soluble solvents. Examples of combinations include methyl ethyl ketone/toluene, methyl ethyl ketone/ethylbenzene, cyclohexanone/cumene, silanohexanol/3-pentanone, +e+t-
Pentyl alcohol/2-methyl-4-pentanone, ethyl alcohol/decane, butyl ether/acetone, etc. can be mentioned, and the mixed composition of these combinations is - For boat fishing, the above combination has a weight ratio of 1: 1
The ratio is preferably 1:1 to 10, preferably 1:1 to 5. As the transfer paper used in the present invention, a conventionally known transfer paper in which a colored image layer is formed on a base sheet using ink using PVB as a binder can be used. Various sheet or film materials can be used as the base sheet of such transfer paper, as long as the colored image layer has good printability and is not compatible with PVB, such as various processed papers, It is possible to use sheets or films made of resin such as polyethylene, polypropylene, polyester, etc., metal foils such as aluminum, or laminates obtained by laminating these materials in a conventional manner. The colored image layer of this transfer paper is not particularly limited as long as it is formed of an ink containing PVB as a binder and a dye and/or pigment as a coloring agent. The colored image layer of the transfer paper is PV
If it is formed with an ink containing B as a binder, the transfer adhesion of this colored image layer to the surface of the plasticized PVB sheet will be extremely good. PV as a binder for this ink
As B, the same kind of material as that used in the above-mentioned plasticized PVB sheet can be suitably used. In addition, this PVB is added in an amount of 100 to 500 parts by weight per 100 parts by weight of the colorant.
The proportion is preferably 200 to 400 parts by weight. If the proportion of PVB is less than 200 parts by weight, the adhesion between the colored image layer and the glass plate will be insufficient;
If the amount is less than 0.00 parts by weight, this tendency becomes noticeable. Further, if the amount is more than 400 parts by weight, the viscosity of the ink is so high that it becomes difficult to form an image on transfer paper, and if it is more than 500 parts by weight, this tendency becomes noticeable. The dye and/or pigment used as the colorant of the ink may be any commonly used dye and/or pigment. For example, the dye may be appropriately selected from azo dyes, anthraquinone dyes, phthalocyanine dyes, etc., and the pigments may include inorganic pigments such as carbon black and titanium white, nitro pigments, and nitroso pigments. The pigment may be appropriately selected from organic pigments such as , azo pigments, and phthalocyanine pigments. These dyes and pigments may be a mixture of multiple types. The image of the colored image layer formed on the base sheet of the transfer paper is not particularly limited. For example, there are band-shaped images with uniform density over the entire area, band-shaped images with a density gradient from one side edge toward the other side edge, and the like.

[Examples] The present invention will be further explained below with reference to Examples and Comparative Examples. In addition, in the following examples and comparative examples, plasticized PVB
The coating appearance of the sheet was evaluated according to the following method. Example 1 The plasticized PVB sheet used and the solvent used as the coating solution are shown below. Plasticized PVB sheet, degree of butyralization 65 mol%,
For laminated glass with a width of 1200 mm, a length of 2000 mm, and a thickness of 760 μm manufactured from plasticized PVB in which 35 parts by weight of di-n-hexyl adipate is blended with 100 parts by weight of PVB with an average degree of polymerization of 2100. Intermediate film. Coating solvent: Methyl ethyl ketone plasticized PVB sheet is heated to 15°C using a sheet conveyor roll.
The sample was transported to a solvent coating section in an atmosphere of 1, and coated using a gravure coating method at a coating liquid roll speed of 5 m/min. At that time, the coating roll used had a diameter of 125 mm, a gravure body portion on which a gravure plate was formed and a length of 600 mm, and a total length of 1600 mm. Then, the interval between the coating roll/sheet conveyance roll on the coating liquid coated side (gravure plate side) was adjusted to 600 μm, and on the other hand, the interval between the coating roll/sheet conveyance roll on the side not coated with the coating liquid (the front side of the gravure plate) was adjusted to 720 μm. It was adjusted. In addition, a liquid scraping blade was attached and brought into contact with the entire area of the coating roll on the front side of the gravure plate. The interval between the coating roll/coating liquid transport roll was set to 200 μm. Coating was performed in this state, and the appearance of the coating immediately after coating was evaluated. Immediately after applying the solvent, a colored image layer on the transfer paper is overlaid on the solvent-coated surface, passed through nip rolls at a temperature of 23°C and a pressure of 3°8 kg/cm2, the base sheet of the transfer paper is peeled off, and the plasticized PVB A colored image was transferred to the surface of the sheet. The plasticized PVB sheet to which the colored image was transferred was dried in a hot air dryer at 80° C. for 1 minute to volatilize the applied solvent, thereby obtaining a plasticized PVB sheet having a colored band on one side. The results are shown in Table 1. In addition, in the above and following examples, the evaluation of the applied appearance of the plasticized PVB sheet was performed according to the following method. Whether the coating liquid is evenly and uniformly applied to the surface of the plasticized PVB sheet is visually evaluated, and the coating line is ranked 1 to 5 in advance as shown in Figure 4.
Evaluations were made based on standard samples divided into five levels, and pass/fail judgments were made by integrating these two evaluations. As for the appearance of the coating line, if it was grade 4 or higher, it was considered to be acceptable. Examples 2 and 3 In Example 1, the procedure was the same as in Example 1, except that the interval between the coating roll/sheet transport roll was 700 μm (Example 2) and 750 μm (Example 3) on the front side of the gravure plate, respectively. It was applied and evaluated. The results are shown in Table 1. Examples 4 and 5 In Example 1, the distance between the coating roll/sheet conveyance roll on the front side of the gravure plate, the distance between the coating roll/coating liquid conveyance roll, and the coating roll speed (in the case of Example 5)
Coating and evaluation were carried out in the same manner as in Example 1, except that , respectively, were changed as shown in Table 1. Table 1 shows the results.
Shown below. Comparative Examples 1 to 3 In Example 1, the applicator roll was not inclined, the interval between the applicator roll/sheet conveyance roll was kept constant, and a liquid scraping blade was provided or not.
It was applied and evaluated in the same manner as above. The results are shown in Table 1. Margin below

【Effect of the invention】

According to the present invention, when forming a colored band on an interlayer film made of a plasticized PVB sheet, the volatile PVB solvent can be applied uniformly along the application line and without any unevenness, and therefore the product It is possible to produce an interlayer film for laminated glass having a colored band with a good appearance.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an apparatus for carrying out the present invention;
FIG. 2 is a front view of the solvent application section, FIG. 3 is a perspective view of the solvent application section, and FIG. 4 is an appearance evaluation diagram of the application line. 1...Plasticized PVB sheet, 2...Applying roll, 3
... Sheet conveyance roll, 4 ... Liquid scraping blade, 5
... Coating liquid conveyance roll, 6... Coating liquid pan, 7...
- Pressure roll, 8... gravure cylinder, 9... transfer paper. Applicant Nippon Monsando Co., Ltd.

Claims (2)

[Claims] (1) Transferring the image layer onto the surface of a plasticized polyvinyl butyral sheet of a transfer paper on which an image layer is formed on a base sheet with an ink containing polyvinyl butyral as a binder and dye and/or pigment as a coloring agent, A method for producing an interlayer film for laminated glass having a colored band on one side in the width direction, the method comprising: a) dissolving volatile polyvinyl butyral on one side of the surface of a plasticized polyvinyl butyral sheet to which an image layer of a transfer paper is transferred; 10 to 2 coating liquids made of solvent
1st step of coating under 0°C conditions; b) Immediately after applying the solvent, a 2nd step of superimposing the image layer of the transfer paper on the surface coated with the coating solution and applying pressure at a temperature of 40°C or lower; c) Next, the base sheet of the transfer paper is peeled off, and the polyvinyl butyral soluble solvent is volatilized and removed. a coating roll arranged so that its axis is inclined vertically to the side;
The application roll is passed horizontally between a pair of rolls consisting of a sheet transport roll disposed horizontally below and opposite the application roll, and holds the coating liquid supplied by the coating liquid transport roll. A method for producing an interlayer film for laminated glass having a colored band, which comprises applying a coating liquid to one side of the surface of a plasticized polyvinyl butyral sheet. (2) The interlayer film for laminated glass having a colored band according to claim (1), wherein in the first step, a coating roll provided with a scraping blade for restricting the spread of the coating solution is used. Production method.