JP2002264548A - Baking sheet for Al and its baking sheet - Google Patents

Abstract

(57) [Summary] [Problem] It is possible to easily attach information to a flexible aluminum product such as a rolled foil by giving information on the spot at the site or the like. Development of a baked sheet for Al that can withstand. A sheet to be baked on an aluminum product (4) to be subjected to a heat treatment, wherein an ink-receiving layer (1) using an inorganic powder and a silicon-containing binder is provided on an underside of a printing sheet on which an ink-receiving layer (1) is located. (2) wherein the silicon-containing binder is trimethylsiloxysilicic acid or R ₃
It is made of a polymer of M units represented by SiO- and Q units represented by Si (O-) _4, and ink information can be provided to the ink receiving layer by a thermal transfer method. Is temporarily attached to an aluminum product via the adhesive layer, and a printing sheet formed by applying the thermal transfer ink information (3) to the ink receiving layer of the sheet and the ink receiving layer of the sheet.
A fired sheet obtained by firing at the above temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a baked sheet for Al which is capable of forming a baked sheet having excellent reflectance and is suitable for forming management labels and the like of aluminum products.

[0002]

2. Description of the Related Art Heretofore, as a management label in a manufacturing process of an aluminum product, a label obtained by applying a heat-resistant paint to a metal plate or performing laser etching has been known. However, in the case of labels mainly made of metal plates, it is necessary to take measures such as riveting when attaching to products such as aluminum slabs. There were difficult problems.

[0003]

SUMMARY OF THE INVENTION The present invention makes it possible to easily attach information to a flexible aluminum product such as a rolled foil by giving information on the spot at the site or the like. The objective is to develop a baked sheet for Al that can withstand the heat.

[0004]

The present invention relates to a sheet to be baked on an aluminum product to be subjected to a heat treatment, wherein an ink receiving layer formed by keeping a mixture using at least an inorganic powder and a silicon-containing binder in a sheet form has a surface. Has a pressure-sensitive adhesive layer on the back surface of the printing sheet, and the silicon-containing binder is trimethylsiloxysilicic acid or a general formula: R ₃
It is composed of a polymer of a monofunctional M unit represented by SiO- (where R is a compound group) and a tetrafunctional Q unit represented by Si (O-) ₄ . A baking sheet for Al, wherein the ink receiving layer can be provided with ink information by a thermal transfer method, and printing by providing thermal transfer ink information to the ink receiving layer of the baking sheet for Al. The present invention provides a fired sheet characterized in that the sheet is temporarily attached to an aluminum product via the adhesive layer, fired at a temperature of 200 ° C. or more, and baked.

[0005]

According to the printing sheet for Al according to the present invention, ink information is applied to the ink receiving layer by a thermal transfer method so that various and flexible printing sheets can be formed on the spot or the like. Can be satisfactorily adhered to a curved surface portion of an aluminum product through the adhesive layer, and can be baked as a baked sheet in which the imparted information is well preserved under heat treatment, thereby being excellent in workability in mounting. Also, the formed fired sheet is
The silica generated by the change of the silicon-containing binder by sintering is sintered to strongly bind and hold the inorganic powder, and is excellent in chemical resistance, heat resistance, weather resistance, reflectance, etc. It can be used as a management label or the like that can withstand the annealing conditions described above.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A baked sheet for Al according to the present invention comprises:
A sheet that is baked on an aluminum product that is subjected to heat treatment, and has an ink receiving layer formed by preserving a mixture using at least an inorganic powder and a silicon-containing binder in the form of a sheet. A silicon-containing binder, wherein the silicon-containing binder is trimethylsiloxysilicic acid or a monofunctional M unit represented by the general formula: R ₃ SiO— (where R is a compound group); O
-) with comprising a polymer of tetrafunctional Q units represented by _4, the ink-receiving layer of the one in which ink information can be given by a thermal transfer method. An example is shown in FIG.
1 is a printing sheet (ink receiving layer) and 2 is an adhesive layer. In the example shown in FIG.
Is applied to form a print sheet, which is temporarily attached to the aluminum product 4 via the adhesive layer 2. Such a printed sheet is in a state in which organic components such as an adhesive layer are lost by baking, and is baked on an aluminum product as a baked sheet.

The printing sheet may be any sheet as long as the ink receiving layer is located on at least one surface in sheet form. Therefore, the printing sheet can be formed in an appropriate form. Incidentally, examples thereof include a form composed of the ink receiving layer itself as in the example of FIG. 1, and a form in which the ink receiving layer 11 is reinforced by the reinforcing base material 12 as in the example of FIG. The reinforcing form is appropriately selected from a method of providing an ink receiving layer on a reinforcing substrate as shown in FIG. 2, a method of impregnating the reinforcing substrate with an ink receiving layer forming material, and a method of interposing a reinforcing substrate in the ink receiving layer. It may be formed by any suitable method. As a reinforcing base material, a resin coating layer, film, fiber,
An appropriate material such as a perforated substrate such as cloth or nonwoven fabric can be used.

The reinforcing substrate may be formed of a material which disappears during heat treatment such as a polymer made of polyester, polyimide, fluororesin or polyamide, or does not disappear by heat treatment such as glass, ceramic or metal. It may be formed of a material. A preferred reinforcing substrate is a low-decomposition type polymer such as ethyl cellulose which is excellent in tensile strength and comprises a coating layer or a film. The thickness of the reinforcing base material can be determined as appropriate.
-100 μm, preferably 3-50 μm, particularly preferably 5-25 μm.

The inorganic powder used for forming the ink receiving layer is as follows:
Improvement of heat resistance (usually about 600 ° C. or less, preferably about 80 ° C.
0 ° C. or less) to form the ground color of the fired sheet. Therefore, any suitable inorganic powder such as metal powder or ceramic powder can be used. Particle size of inorganic powder is 50μm
Hereinafter, the thickness is generally 0.05 to 20 μm, but is not limited thereto. Adhering the inorganic powder to a flake base such as mica and blending it as a flake powder is effective in improving the reflectance or hiding power (hiding the ground color of aluminum products).

[0010] Examples of commonly used inorganic powders include:
White substances such as silica, titania, alumina, zinc white, zirconia, calcium oxide, mica, potassium titanate, and aluminum borate are exemplified. Further, metal compounds such as carbonates, nitrates and sulfates which are oxidized at a firing temperature or lower to become such oxidized white ceramics may 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.

As the silicon-containing binder, trimethylsiloxysilicic acid or a monofunctional M unit represented by the general formula: R ₃ SiO— and a tetrafunctional Q unit represented by Si (O—) ₄ For example, an appropriate resin known as a tackifier of a silicone-based pressure-sensitive adhesive, which is composed of a polymer (MQ resin) having the above formula, may be used. In the general formula, for example, R is 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 vinyloxy group. It may be a compound group having an appropriate structural unit such as a hydrolyzable group. The silicon-containing binder that can be preferably used has excellent shape retention.

For forming the ink receiving layer or the printing sheet, for example, one or more of inorganic powder and a silicon-containing binder are mixed by a ball mill or the like using an organic solvent or the like as necessary, and the mixed solution is appropriately mixed. It can be carried out by a method such as spreading on a supporting material such as a reinforcing base material or a separator and drying as needed. In this case, the ratio of the inorganic powder and the silicon-containing binder used can be appropriately determined according to the handleability and strength of the printing sheet, the strength of the fired sheet, the hiding power, and the like. From the viewpoint of compatibility between the degree of coloring such as white color after sintering and the strength, 1 to 1000 parts by weight, preferably 20 to 200 parts by weight, particularly 40 to 120 parts by weight of inorganic powder is used per 100 parts by weight of the silicon-containing binder. Is preferred.

As the above-mentioned necessary organic solvent, an appropriate one can be used. Generally, toluene, xylene, butyl carbitol, ethyl acetate, butyl cellosolve acetate, methyl ethyl ketone, methyl isobutyl ketone and the like are used. The mixed liquid is not particularly limited, but is preferably prepared so that the solid content concentration is 5 to 85% by weight from the viewpoint of expandability and the like. At the time of its preparation, an appropriate additive such as a dispersant, a plasticizer, a combustion aid and the like can be blended as needed.

The method of developing the mixed liquid is optional, but a method excellent in layer thickness controllability such as a doctor blade method or a gravure roll coater method is preferable. 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 printing sheet or ink-receiving layer to be formed can be determined as appropriate, but is generally 5 μm to 5 mm, preferably 10 μm to 1 mm, particularly preferably 20 to 200 μm.

In forming the above-described ink receiving layer,
For the purpose of improving flexibility, shape retention, chemical resistance and ink fixability, for example, silicone rubber, cellulose polymer, hydrocarbon polymer, vinyl or styrene polymer, acetal polymer, butyral polymer, acrylic A series polymer, a polyester polymer, a urethane polymer, a cellulose polymer, and various organic compounds such as waxes and waxes can be blended as required. Such a compounding agent may be used alone or in combination of two or more.

It is particularly preferable to use a silicone rubber in combination for improving flexibility and chemical resistance. Any suitable silicone rubber can be used without any particular limitation. 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 have excellent shape retention and flexibility.

The amount of the silicone rubber used is from 1 to 1000 parts by weight, preferably from 5 to 500 parts by weight, especially from 10 to 100 parts by weight of the silicon-containing binder, from the viewpoint of improving the chemical resistance.
~ 200 parts by weight are preferred. When silicone rubber is used in combination, the use ratio of the inorganic powder described above is based on the total amount of the silicon-containing binder and the silicone rubber, from the viewpoint of handleability and strength of the printing sheet, strength of the fired sheet, hiding power, and the like. preferable.

On the other hand, it is particularly preferable to use a cellulosic polymer such as ethyl cellulose in combination from the viewpoints of the fixing property of the ink by the thermal transfer method, the improvement of the strength of the printing sheet, and the baking property by baking. The amount of the organic compound such as the above-mentioned cellulosic polymer other than the silicone rubber used is
Per 100 parts by weight of a silicon-containing binder, and in the case of a silicone rubber combined use, per 100 parts by weight thereof
1 to 1000 parts by weight, preferably 20 to 200 parts by weight, especially 4
The amount is generally, but not limited to, 0 to 150 parts by weight.

The printing sheet may be formed in a porous form for the purpose of smoothly volatilizing the decomposition gas by heating. By the way, if a temporary adhesive layer is provided, the sheet may swell due to the decomposition gas generated by the heating, and this can be prevented by using a porous printing sheet. The formation of the porous printing sheet is performed by an appropriate method such as a method of forming a large number of fine holes in the printing sheet by a punching method or the like, a method of using a perforated base material such as a woven fabric or a nonwoven fabric as a reinforcing base material, or the like. be able to.

The baked sheet for Al is temporarily adhered to an aluminum product to be subjected to a heat treatment, is formed into a baked sheet under the heat treatment, and is baked and fixed. 2 are provided. The adhesive layer is provided on the printing sheet 1 such that the ink receiving layer is exposed on the surface. For forming the adhesive layer, an appropriate adhesive substance such as a rubber-based, acrylic-based, silicone-based, or vinylalkyl ether-based adhesive can be used. The attachment of the adhesive layer
A method of applying an adhesive substance to a predetermined surface of a printing sheet by an appropriate coating method such as a doctor blade method or a gravure roll coater method, or a method of applying an adhesive layer provided on a separator according to the above method to a printing sheet. It can be performed by an appropriate method such as a method of transferring to a surface.

The pressure-sensitive adhesive layer may be provided in an interspersed state by an appropriate coating method such as a rotary screen method for the purpose of smoothly volatilizing the decomposition gas during the heat treatment. The thickness of the adhesive layer can be determined according to the purpose of use of the aluminum product and the like. Generally 1 to 500 μm, especially 3
厚 100 μm, especially 5-50 μm. The adhesive layer provided is preferably covered with a separator 21 or the like as shown in FIG. 2 to prevent contamination and the like until the adhesive layer is temporarily attached to an aluminum product. The temporary attachment of the baked sheet for aluminum to the aluminum product can be carried out manually or by an automatic bonding method using a robot or the like.

When temporarily attached to an aluminum product to be subjected to a heat treatment, the baked sheet for Al is a printed sheet.
The formation can be performed by giving the thermal transfer ink information 3 to the ink receiving layer of the printing sheet 1 as in the example of FIG. The print sheet has engraving information consisting of holes or irregularities in addition to the thermal transfer ink information, morphological information obtained by punching the sheet into an appropriate form, or a handwriting method, a coating method using a pattern mask, a pattern formed on a transfer paper. Appropriate information elements such as other ink information based on various printing methods such as a transfer method may be combined.

As the ink, an appropriate ink using a coloring agent such as a pigment, particularly, a heat-resistant coloring agent such as an inorganic material can be used, and a glass frit or the like is used for the purpose of improving fixing power by heat treatment. May be contained. The thermal transfer ink information can be provided by using a thermal transfer printer and an ink sheet, so that arbitrary ink information can be provided on an occasional basis, with high accuracy, and efficiently. In addition, the printing sheet provided with the thermal transfer ink information is temporarily attached to the aluminum product through the adhesive layer and baked, so that the provided information such as the thermal transfer ink information is satisfactorily preserved on the aluminum product as a fired sheet. Can be burned.

The ink sheet can be obtained, for example, by adding a binder to the ink and holding the ink on a supporting substrate made of a film, cloth or the like. Therefore, thermal transfer ink information can be formed using a known ink or its ink sheet by a thermal transfer method or the like. A preferable ink sheet from the viewpoint of heat resistance and the like is a metal oxide type colorant composed of an oxide of an appropriate metal such as iron, nickel, chromium, cobalt, or copper, and a wax or resin for holding the colorant. An ink containing an appropriate organic binder as a component is used.

The thermal transfer ink information to be applied to the ink receiving layer is arbitrary, and for example, 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 fired sheet and the ink information after the heat treatment.

The heat treatment of the print sheet temporarily attached to the aluminum product can be performed under appropriate heating conditions according to the heat resistance of the aluminum product. Generally 1200 ° C
Hereinafter, the heating temperature is set to 200 to 700 ° C, particularly 350 to 600 ° C. The organic component such as the adhesive layer disappears by the heat treatment, and the silicon-containing binder or the like forming the ink receiving layer hardens while being fused with the information of the thermal transfer ink, is formed into a fired sheet, and is baked and fixed to the aluminum product.

Accordingly, the baked sheet for Al or its printed sheet can be used for various purposes such as painting on various aluminum products such as slabs and rolled foils, and providing identification marks composed of coloring or color-specific information and bar codes. In particular, it can be preferably used as a management label in an annealing step or the like. The aluminum product may have any form such as a flat form or a curved form such as a container.

[0029]

Example 1 100 parts of MQ resin (parts by weight, hereinafter the same), 17 parts of silicone rubber having a weight average molecular weight of about 300,000 (all manufactured by Shin-Etsu Chemical Co., Ltd.), 60 parts of potassium titanate, and 60 parts of ethyl cellulose were used. The dispersion was homogeneously mixed with toluene, and the resulting dispersion was applied on a polyester film having a thickness of 75 μm by a doctor blade method and dried to form an ink receiving layer having a thickness of 60 μm, thereby obtaining a printing sheet.

On the other hand, a toluene solution containing 100 parts of polybutyl acrylate having a weight average molecular weight of about 1,000,000 was applied by a doctor blade method on a 70 μm thick glassine paper separator treated with a silicone-based release agent and dried. Then, an adhesive layer having a thickness of 20 μm was formed, which was adhered to the surface of the ink receiving layer, and the polyester film was peeled off to obtain a baked sheet for Al.

Next, thermal transfer ink information consisting of a bar code is applied to the ink receiving layer of the printing sheet for Al using an ink ribbon holding a wax-based ink containing a metal oxide type black pigment and a thermal transfer printer. A printed sheet was obtained.

Example 2 A baked sheet for Al and a printed sheet were obtained in the same manner as in Example 1 except that aluminum borate was used in place of potassium titanate.

Comparative Example 1 A baked sheet for Al and a printed sheet were obtained in the same manner as in Example 1 except that silica powder (Aerosil) was used instead of the MQ resin.

Comparative Example 2 A baked sheet for Al and a printed sheet were obtained in the same manner as in Example 1 except that silicone rubber was used instead of the MQ resin.

Evaluation test The separator was peeled off from the printed sheet obtained in each of the examples and comparative examples, and was temporarily attached to an aluminum slab via the adhesive layer.
Annealed at 530 ° C. for 12 hours to form a fired sheet having ink information composed of a black barcode on a white background, and evaluated the sintering strength by a picking test using a cellophane-based adhesive tape, The reflectance was evaluated using a bar code verifier. In the examples, the organic components in the ethyl cellulose and the adhesive layer of the printing sheet were burned off by the heat treatment. In the fired sheet, the MQ resin and / or the silicone rubber were changed into silica and remained as a cured product.

The above results are shown in the following table. Example 1 Example 2 Comparative Example 1 Comparative Example 2 Sintering strength No change No change Fracture Fracture Reflectance (%) 80 50 80 80

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a baked sheet for Al.

FIG. 2 is a cross-sectional view of another example of a baked sheet for Al.

[Explanation of symbols]

 1: Printing sheet 11: Ink receiving layer 12: Reinforcing substrate 2: Adhesive layer 3: Thermal transfer ink information 4: Aluminum product

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Makoto Kai 1-2-1, Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation F-term (reference) 2H111 CA03 CA04 CA12 CA30 CA31 CA42 4F100 AA01A AA20A AA34 AJ06 AK25 AK52 AN02 AR00C AT00B BA03 DG10 EC04A GB90 JB01 JD14A JJ03 JK06 JL01 JL05 JL09 JL13C JN06

Claims (2)

[Claims] 1. An aluminum product subjected to a heat treatment
The sheet to be baked, inorganic powder and silicon-containing binder
Do not keep at least the mixture using
Ink-receiving layer on the back side of the printing sheet
It has an adhesive layer, and the silicon-containing binder is
Methylsiloxysilicic acid or the general formula: R ₃SiO- (just
R is a compound group. Monofunctional M unit represented by
And Si (O-)₄And a tetrafunctional Q unit represented by
And heat transfer to the ink receiving layer.
That it is possible to add ink information
Characterized baking sheet for Al. 2. A printing sheet obtained by providing thermal transfer ink information to the ink receiving layer of the printing sheet for Al according to claim 1 is temporarily attached to an aluminum product via the adhesive layer.
A fired sheet fired at a temperature of 0 ° C. or higher.