JP2002091313A - Printing sheet and printed sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printing sheet from which such a calcined sheet can be formed as can be adhered firmly to even the dew-condensed subject to be adhered, is hardly peeled off by washing with water, etc., and has excellent chemical resistance, heat resistance, weather resistance, hiding power or reflectance, etc., like a management label which is effectively usable from the time when a cathode ray tube is manufactured to the time when it is recycled, while satisfying the merits such as the property of adhering to a curved surface of the subject to be adhered by heating after information is imparted optionally, the property of optionally forming a great variety of printed sheets necessary for a production system of many kinds in a small scale at the site, etc., and the property of simply adhering to the subject to be adhered. SOLUTION: This printing sheet has a layer formed into a sheet shape on the front surface of a sheet base (1) made of a mixture of at least inorganic powder, a MQ resin and silicone rubber and a water-soluble adhesive layer (2) on the rear surface of the base (1). The printed sheet is obtained by imparting the ink information (3) to the surface of the front layer of a shape- retaining layer in the printing sheet by a thermal transfer printing method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing sheet having excellent concealing power or reflectance and good adhesion to a dew condensation surface and suitable for forming a management label and the like, and a thermal transfer type printing sheet using the same for excellent heat resistance. About.

[0002]

2. Description of the Related Art Conventionally, as a printing sheet which can be used as a management label in a cathode ray tube manufacturing process, an acrylic or rubber-based adhesive layer is provided on one surface of a sheet substrate in which inorganic powder is preserved with polyorganosiloxane. It has been known that ink information is added to the ink (Japanese Patent No. 265
No. 4735). However, there is a problem in that when the adhesive is adhered to the glass panel on which dew condensation occurs and is subjected to a water washing step, the management label falls off and the label function is not completed. Dew condensation in the cathode ray tube manufacturing process occurs on many occasions, for example, when manufacturing in a factory in a humid environment near the equator or when a panel cooled by outside air in winter or the like is brought into the factory.

In addition, in addition to the problem of dropping due to the above-mentioned dew condensation, the conventional management label also has a problem that it cannot be used in a recycling process for collecting reworkable parts that can be reused from an adherend such as a cathode ray tube. By the way, in the above-mentioned cathode ray tube, the rework parts are recovered through a salvage process of separating the panel and the funnel by immersion in hot nitric acid, in which case the ink information of the management label given to the cathode ray tube is lost and the management label is used. Cannot manage rework parts.

[0004]

SUMMARY OF THE INVENTION The present invention relates to a variety of printing sheets which can be fixed to an adherend under heat treatment by adding information to the surface of the printing sheet and required for a curved surface fixing property and a high-mix low-volume production system. While satisfying the advantages such as flexibility and easy fixation to the adherend, it can adhere well to the adherend that has formed dew and does not easily fall off by washing, etc., and can be effectively used from CRT production to salvage. An object of the present invention is to develop a printing sheet capable of forming a fired sheet having excellent chemical resistance, heat resistance, weather resistance, hiding power, reflectance, and the like, such as a management label.

[0005]

According to the present invention, there is provided a sheet base material having a layer formed by preserving a mixture of at least an inorganic powder, an MQ resin and a silicone rubber in a sheet form on a back surface thereof.
Printing sheet characterized by having a water-soluble adhesive layer,
And a printing sheet provided with ink information by a thermal transfer method on a surface of a shape retaining layer of the printing sheet.

[0006]

The printing sheet according to the present invention is flexible and can form a wide variety of printing sheets by giving ink information by an appropriate method such as a thermal transfer method. The sintering sheet can be easily adhered to a curved surface portion and the like, and hardly falls off by a washing process or the like, and can be easily fixed as a fired sheet in which the applied information is well preserved by a heating process. Further, the formed fired sheet is excellent in chemical resistance, heat resistance, weather resistance, hiding power, reflectance, and the like, and can be used, for example, as a management label that can be effectively used from CRT production to salvage.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION A printing sheet according to the present invention has a water-soluble adhesive on the back surface of a sheet substrate having a layer formed by preserving a mixture of at least inorganic powder, MQ resin and silicone rubber in the form of a sheet. The printing sheet has ink information by a thermal transfer method on the surface of the shape retaining layer. Examples of the printing sheet and the printing sheet are shown in FIGS. 1 is a sheet substrate,
2 is a water-soluble adhesive layer, 3 is ink information, 4 is an adherend, and 21 is a separator. Therefore, FIG. 1 shows an example of a printing sheet, and FIG. 2 shows another example of a printing sheet.

The sheet substrate in the printing sheet only needs to have a layer formed by preserving the above mixture in a sheet form, that is, a sheet-shaped preserving layer on the surface, and thus can be formed in an appropriate form. it can. Examples thereof include a sheet form composed of a shape retaining layer itself as shown in FIG. 1 and a sheet form formed by reinforcing a shape retaining layer 11 with a reinforcing base material 12 as shown in FIG.

The above-mentioned reinforcing mode includes a method of providing a shape-retaining layer on a reinforcing substrate as shown in FIG. 2, a method of impregnating the reinforcing material with a material for forming a shape-retaining layer, and a method of embedding a reinforcing material in a shape-retaining layer. It may be formed by an appropriate method such as a method of interposing. The reinforcing substrate may be formed of a material that disappears during heat treatment, such as a polymer made of polyester, polyimide, fluororesin, polyamide, or the like, or may be formed of a material that does not disappear by heat treatment, such as glass or ceramic or metal. It may be. Therefore, as the reinforcing base material, an appropriate material such as a resin coating layer, a film, a fiber, a cloth, a nonwoven fabric, a porous material such as a metal foil or a net, or a nonporous material can be used.

The inorganic powder used for forming the shape-retaining layer is used for improving heat resistance (usually about 500 ° C. or less, preferably about 800 ° C. or less) and for forming the ground color of the printed sheet.
Therefore, appropriate powder such as metal powder and ceramic powder can be used. One or more inorganic powders can be used, and the particle size is 50 μm or less, particularly 0.05 to 20 μm.
Is common but not limited to this. Adhering the inorganic powder to a flake base such as mica and blending it as a flake-shaped powder is effective in improving the hiding power or the reflectance.

Examples of commonly used inorganic powders include:
White substances such as silica, titania, alumina, zinc white, calcium oxide, mica, potassium titanate, and aluminum borate are exemplified. Further, metal compounds such as carbonates, nitrates, and sulfates that are oxidized at a temperature not higher than the temperature at which the printing sheet is subjected to heat treatment to become such an oxidized white ceramic can also be mentioned. Needless to say, needle-like crystals such as potassium titanate and aluminum borate can be preferably used in terms of whiteness, sintering strength and the like.

Red substances such as manganese oxide / alumina, chromium oxide / tin oxide, iron oxide, cadmium sulfide / selenium sulfide, blue substances such as cobalt oxide, zirconia / vanadium oxide, chromium oxide / divanadium pentoxide, and chromium oxide・ Cobalt oxide ・ Iron oxide ・ Manganese oxide and chromate,
Black substances such as permanganate, yellow substances such as zirconium / silicon / praseodymium, vanadium / tin, chromium / titanium / antimony, green substances such as chromium oxide, cobalt / chromium, alumina / chromium, aluminum / manganese / iron /
Pink colored substances such as silicon and zirconium are also examples of inorganic powders.

The MQ resin used as a binder for holding the inorganic powder in the form of a sheet includes a general formula: R ₃ S, which is known as a tackifier of a silicone adhesive.
a monofunctional M unit represented by iO- and Si (O-) ₄
An appropriate polymer consisting of a polymer with a tetrafunctional Q unit represented by In the general formula, R is, for example, an aliphatic hydrocarbon group such as a methyl group, an ethyl group or a propyl group, an aromatic hydrocarbon group such as a phenyl group, an organic group such as an olefin group such as a vinyl group, or a vidroxyl group. Having an appropriate structural unit such as a hydrolyzable group such as MQ resins that can be preferably used are those having excellent shape retention of inorganic powder.

Similarly to the above-mentioned MQ resin, the silicone rubber used as a binder for holding the inorganic powder in a sheet form is not particularly limited, and an appropriate rubber can be used. Various modified silicone rubbers such as phenol-modified products, melamine-modified products, epoxy-modified products, polyester-modified products, acryl-modified products and urethane-modified products can also be used. Silicone rubbers that can be preferably used are excellent in shape retention of inorganic powder and flexibility in imparting flexibility to the obtained sheet substrate.

The sheet substrate is formed, for example, by mixing inorganic powder and M
One or more of each of the Q resin and the silicone rubber are mixed by a ball mill or the like using an organic solvent or the like as necessary, and the mixed solution is used in an appropriate manner as necessary to form a support material such as a reinforcing base material or a separator. It can be carried out by, for example, a method in which the film is developed and dried. The use ratio of the MQ resin and the silicone rubber to the inorganic powder can be appropriately determined according to the handleability of the printing sheet, the strength of the printing sheet, the hiding power, and the like. Generally, the amount is 20 to 800 parts by weight, preferably 30 to 500 parts by weight, particularly 100 to 300 parts by weight, per 100 parts by weight of the inorganic powder based on the total amount of the MQ resin and the silicone rubber.

The ratio of the MQ resin and the silicone rubber to be used may be appropriately determined according to the sintering strength, chemical resistance and the like. Generally 1 to 10 per 100 parts by weight of MQ resin
00 parts by weight, in particular 3 to 500 parts by weight, in particular 5 to 200 parts by weight, of silicone rubber are used. Insufficient MQ resin results in poor sintering strength, and insufficient silicone rubber results in poor chemical resistance such as heat-resistant nitric acid. In order to withstand the salvage process of a CRT, especially its immersion treatment in hot nitric acid, 1 to 100 parts by weight of MQ resin
Particular preference is given to using from 0 to 200 parts by weight of silicone rubber.

As the above-mentioned necessary organic solvent, any suitable organic solvent can be used, and generally, toluene, xylene, butyl carbitol, ethyl acetate, butyl cellosolve acetate, methyl ethyl ketone, methyl isobutyl ketone and the like are used. The mixed solution has a solid content concentration of 5 to 85 from the viewpoint of, for example, but not limited to, developability.
It is preferable to prepare so that it may be% by weight. In the preparation, an appropriate additive such as a dispersant, a plasticizer, and a combustion aid can be added as needed.

The developing method is preferably a method excellent in layer thickness controllability such as a doctor blade method or a gravure roll coater method. It is preferable to perform a sufficient defoaming treatment by using an antifoaming agent together so that no air bubbles remain in the spread layer. The thickness of the sheet substrate to be formed or the thickness of the shape-retaining layer is appropriately determined, but is generally 5 μm to 5 mm, preferably 10 μm to 1 mm, particularly 20 μm.
２００200 μm.

The shape-retaining layer, the sheet substrate, and the printing sheet may be formed in a porous form, if necessary, for the purpose of smoothly evaporating the decomposition gas by heating. Incidentally, there is a case where the printed sheet swells due to the decomposition gas generated by heating the temporarily worn water-soluble pressure-sensitive adhesive layer, which can be prevented by using a porous sheet base material or the like. The formation of the porous sheet base material includes, for example, a method in which a number of fine holes are formed in the sheet base material 1 by a punching method, a woven or nonwoven fabric, a metal foil or a net in which a number of fine holes are formed in a reinforcing base material, or the like. Can be performed by an appropriate method such as a method using

For the purpose of improving ink fixability, the above-mentioned shape-retaining layer may be, for example, a hydrocarbon polymer, a vinyl or styrene polymer, an acetal polymer or a butyral polymer, an acrylic polymer or a polyester polymer, or a urethane. An organic compound such as a base polymer, a cellulose base polymer, a cellulose base polymer, and various waxes or waxes can be added as necessary.
From the viewpoint of improving the fixing property of the ink and the strength of the shape-retaining layer by the thermal transfer method, it is particularly preferable to incorporate a cellulose-based polymer such as ethyl cellulose. The amount of organic compound used is
The amount is generally 5 to 200 parts by weight, preferably 10 to 100 parts by weight, per 100 parts by weight of the total of the MQ resin and the silicone rubber, but is not limited thereto.

The printing sheet has a water-soluble adhesive layer 2 provided on the back surface of a sheet substrate 1 having a shape-retaining layer on the surface as shown in the figure. Therefore, when the shape-retaining layer is exposed on both the front and back surfaces of the sheet base as in the example of FIG. 1, a water-soluble adhesive layer can be provided on any one side thereof, but only one side of the sheet base 1 as in the example of FIG. When the shape-retaining layer 11 is exposed, it is necessary to provide a water-soluble adhesive layer on the side where the shape-retaining layer is not exposed.

The purpose of the adhesive layer is to temporarily adhere a printed sheet or the like to an adherend, and in this case, in the present invention, for example, the adherend having a dew condensation on its surface is exposed to moisture, such as an adherend. A water-soluble pressure-sensitive adhesive layer is provided so that even in the case of an adherend that does not easily develop an adhesive strength, a sufficient adhesive strength is developed and a temporarily adhered printed sheet or the like is hardly dropped off even when subjected to a washing process or the like. .
For the formation of the water-soluble adhesive layer, for example, a methoxyethyl acrylate polymer or a vinyl alcohol polymer,
Using an appropriate adhesive substance such as an adhesive made of a water-soluble polymer or a hydrophilic polymer such as a vinylpyrrolidone polymer, an acrylamide polymer, an acrylic acid copolymer, a vinyl methyl ether polymer, or a cellulose polymer. sell.

Among them, methoxyethyl acrylate polymers, especially methoxyethyl acrylate polymers obtained by copolymerizing methoxyethyl acrylate, 2-ethylhexyl acrylate, vinyl acetate and acrylic acid, are preferably used from the viewpoint of the stability of adhesive strength and the like. . For the adhesive, for example, an appropriate component such as a tackifier such as glycerin, polyethylene glycol, polyether polyol, polyoxyethylene phenol ether, or polyoxyethylene alkyl phenol ether, a cross-linking agent, or a filler may be added as necessary. it can.

The water-soluble pressure-sensitive adhesive layer is formed by applying a pressure-sensitive adhesive to a predetermined surface of a sheet substrate by an appropriate coating method such as a doctor blade method or a gravure roll coater method, or by providing a method on a separator according to the method. It can be performed by an appropriate method according to a method of forming an adhesive tape or the like, such as a method of transferring the water-soluble adhesive layer to a predetermined surface of a sheet substrate. Further, the water-soluble pressure-sensitive adhesive layer can be provided in a dotted state for the purpose of smoothly volatilizing a decomposition gas when a printing sheet or the like is subjected to a heat treatment. In that case, it is more preferable that the sheet base material has the above-mentioned porous form. The dot-like water-soluble adhesive layer can be formed by a coating method such as a rotary screen method.

The thickness of the water-soluble pressure-sensitive adhesive layer to be provided can be determined according to the adherend, the purpose of use, and the like.
m, especially 5 to 200 μm. Note that the water-soluble pressure-sensitive adhesive layer provided until the temporary adhesion to the adherend is FIG.
It is preferable to cover with a separator 21 or the like to prevent contamination and the like.

The printing sheet according to the present invention is temporarily attached to the adherend 4 via the water-soluble adhesive layer 2 as it is or as a printing sheet having information 3 added to the surface of the shape retaining layer 1 as shown in the example of FIG. The printing sheet or the heat-treated body of the printing sheet is fixed to the adherend under heat treatment. At the time of the heat treatment, a method may be employed in which an object to be fixed is attached to a printing sheet and heated to fix the object to the adherend via the heat-treated body.

The printing sheet is formed by an appropriate method such as a method of providing ink information or engraving information comprising holes or irregularities on the surface of the shape retaining layer of the printing sheet, or a method of punching the printing sheet into an appropriate form. Can be done with It is also possible to form a print sheet composed of a composite of the above-mentioned information elements and a composite sheet of information formed by other various methods. The ink information can be provided by an appropriate printing method such as a handwriting method, a coating method via a pattern mask, a transfer method of a pattern provided on transfer paper, or a forming method by a printer. In particular, a printing method using a printer, particularly a thermal transfer printer, is more preferable because arbitrary ink information can be provided on an occasion, accurately and efficiently.

As the ink for forming the ink information, an appropriate ink using a coloring agent such as a pigment, especially an inorganic heat-resistant coloring agent can be used. A glass frit may be contained for the purpose. An ink sheet such as a print ribbon to be applied to a thermal transfer printer or the like can be obtained, for example, by adding a binder such as a wax or a polymer to the ink and holding the ink on a supporting substrate made of a film or cloth. Therefore, a known ink or its ink sheet can be used by a thermal transfer method or the like.

The ink information to be applied is arbitrary, and appropriate ink information such as print information, a picture pattern, and a bar code pattern may be applied. When an identification label such as a management label is formed, it is preferable that a good contrast or a difference in color tone is formed between the printing sheet and the ink information after the heat treatment.
The step of giving the ink information or form to the shape retaining layer of the printing sheet may be before or after the printing sheet is temporarily attached to the adherend. When ink information is formed by a printer, it is customary to temporarily attach the ink information to an adherend as a print sheet to which ink information has been added in advance, and the print sheet according to the present invention is as shown in FIG. Ink information 3 is applied to the surface of the shape retaining layer (1) of the printing sheet 1 by a thermal transfer method.

For the temporary attachment of the printing sheet or the printing sheet to the adherend, an automatic bonding method using a robot or the like can be employed. The heating treatment of the printing sheet or the printing sheet temporarily attached to the adherend includes: The heating can be performed under appropriate heating conditions depending on the heat resistance of the adherend. In general, the heating temperature is 800 ° C. or less, particularly 200 to 650 ° C., particularly 250 to 550 ° C. The organic resin such as the water-soluble pressure-sensitive adhesive layer disappears by the heat treatment, and the MQ resin and the silicone rubber forming the printing sheet harden while being fused with the ink information, form a fired sheet, and adhere to the adherend.

The printing sheet or printing sheet according to the present invention can be applied to various articles such as ceramics, glass products, ceramic products, metal products, enameled products, etc., and can be distinguished from information such as coloring or color-coded information and bar codes. It can be preferably used for various purposes such as marking. Above all, because it has excellent chemical resistance, such as withstanding immersion in hot nitric acid and retaining its ink information well, from the production of cathode ray tubes to recycling it and collecting rework parts Can be preferably used for forming a management label.
The adherend may have an arbitrary form such as a flat form or a curved form such as a container.

[0032]

EXAMPLE 1 130 parts (parts by weight, hereinafter the same) of MQ resin, 30 parts of silicone rubber (all manufactured by Shin-Etsu Chemical Co., Ltd.), 80 parts of potassium titanate, and 60 parts of ethylcellulose were homogeneously mixed with toluene. The dispersion was applied on a polyester film having a thickness of 75 μm by a doctor blade method and dried to form a shape-retaining layer having a thickness of 55 μm, thereby obtaining a sheet substrate.

On the other hand, methoxyethyl acrylate 43
, A toluene solution containing 100 parts of a methoxyethyl acrylate-based polymer having a weight average molecular weight of 200,000 obtained by copolymerizing 44 parts of 2-ethylhexyl acrylate, 4 parts of vinyl acetate and 9 parts of acrylic acid was treated with a silicone-based release agent. It is coated on a 70 μm thick glassine paper separator by the doctor blade method and dried to a thickness of 15 μm.
A water-soluble pressure-sensitive adhesive layer having a thickness of μm was formed, which was adhered to the surface of the shape-retaining layer, and the polyester film was peeled off to obtain a printing sheet.

Next, ink information consisting of a bar code is applied to the shape retaining layer of the printing sheet by using a commercially available ink ribbon holding a wax-based ink containing a metal oxide-based black pigment and bismuth glass and a thermal transfer printer. Then, a printed sheet was obtained.

Example 2 A printing sheet and a printing sheet were obtained in the same manner as in Example 1 except that aluminum borate was used instead of potassium titanate.

Comparative Example 1 Example 1 was repeated except that the silicone rubber was replaced with MQ resin.
A printing sheet and a printing sheet were obtained in accordance with

Comparative Example 2 Example 1 except that the MQ resin was replaced with silicone rubber.
A printing sheet and a printing sheet were obtained in accordance with

Comparative Example 3 A printing sheet and a printing sheet were obtained in the same manner as in Example 1 except that the water-soluble pressure-sensitive adhesive layer was replaced with a pressure-sensitive adhesive layer made of polybutyl acrylate having a weight average molecular weight of 1,000,000.

Comparative Example 4 A printing sheet and a printing sheet were obtained in the same manner as in Example 1 except that the water-soluble adhesive layer was replaced with an adhesive layer made of polylauryl acrylate having a weight average molecular weight of 1,000,000.

Evaluation Test The separator was peeled off from the printed sheets obtained in Examples and Comparative Examples, and the separator was temporarily attached to a glass plate via the (water-soluble) adhesive layer, and was immersed in water for 5 minutes. The glass plate was heated at 470 ° C. for 30 minutes (in air) and fired to obtain a glass plate having a fired sheet having black barcode ink information fixed on a white background. In addition, the organic components in the ethyl cellulose, the water-soluble adhesive layer, and the like of the printing sheet were burned off by the heat treatment. In the fired sheet, MQ resin and / or silicone rubber remained as a cured product.

Sintering Strength The surface of the fired sheet was rubbed with a cotton cloth to examine the fixing power of the ink information and the fixing power to the glass plate, and evaluated according to the following criteria. Good: When the ink information maintains the same readability as before the test without the falling off of the fired sheet. Poor: When the fired sheet is missing and the ink information becomes illegible.

Reflectance The reflectance of the fired sheet on a white background was measured at a wavelength of 400 to 80.
The light of 0 nm was examined.

Chemical resistance The fired sheet was placed in a 15% nitric acid solution at 80.degree.
After immersion for 5 minutes, it was taken out and evaluated by the same method as in the above-mentioned sintering strength test.

The results are shown in the following table. Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Immersion in water Maintain adhesion Maintain adhesion Maintain adhesion Maintain adhesion Drop off Drop off Sintering strength Good Good Good Bad --- Reflectance (%) 80 50 80 80-- Good chemical resistance Good Good Bad * 1 Bad * 2--* 1: Loss of ink information due to lack of fired sheet surface * 2: Blurred ink information

In the above, the printed sheets of Comparative Examples 3 and 4 were not subjected to immersion in water, and were therefore subjected to a baking treatment while avoiding the problem of falling off. The same results as in Example 1 were obtained for the properties.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a printed sheet.

FIG. 2 is a cross-sectional view of an example of a printing sheet.

[Explanation of symbols]

 1: Sheet substrate (shape retaining layer) 11: Shape retaining layer 12: Reinforcing substrate 2: Water-soluble adhesive layer 3: Ink information layer 4: Adherend

Claims (4)

[Claims] 1. A water-soluble adhesive layer is provided on the back surface of a sheet substrate having a layer formed by preserving a mixture of at least inorganic powder, MQ resin and silicone rubber in a sheet form on the back surface. Printing sheet. 2. The printing sheet according to claim 1, wherein the inorganic powder is a needle-like crystal. 3. The printing sheet according to claim 1, wherein the mixture for forming the shape-retaining layer is used in combination with a cellulosic polymer. 4. A printing sheet according to claim 1, wherein the surface of the shape-retaining layer of the printing sheet according to claim 1 is provided with ink information by a thermal transfer method.