JPH08150680A - Heat resistant printing base material and label - Google Patents

Abstract

PURPOSE: To obtain a heat resistant printing base material or a label which can give a pattern with high density by thermal transfer method and can issue a label as circumstances demand, has excellent heat resistance, abrasion resistance, and chemical resistance such as solvent resistance, and can give a thermal transfer pattern which endures heat treatment, solvent cleaning treatment, and treatment for wiping it. CONSTITUTION: A label consists of a heat resistant printing base material 1 having an inorganic powder layer with a surface roughness of 0.01-0.2μm based on Ra formed of an inorganic powder shaped into a sheet by using at least one kind out of an aromatic polyamide and a polyimide as a binder, and of an ink pattern 2 arranged on the inorganic powder layer of the heat resistant printing base material. Accordingly, when an ink receive layer which uses an ultraviolet setting resin or a heat fixing ink is used, a heat transfer pattern is excessively excellent in heat resistance and solvent resistance, so that it is not extinguished by solder flow, solvent cleaning, and treatment for wiping it, and pattern retaining property is excellent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is capable of providing a high density pattern by a thermal transfer method and is excellent in chemical resistance such as heat resistance, scratch resistance and solvent resistance, and is used for identifying a printed circuit board mounting process or the like. The present invention relates to a heat-resistant printing substrate capable of forming a label and the like, and the label thereof.

[0002]

2. Description of the Related Art Heretofore, there has been known an identification label formed by forming a pattern with a curable ink on a metal nameplate on which a pattern is engraved, a heat-resistant plastic sheet or a metal plate. However, as the production system changed to high-mix low-volume production, it was difficult to issue an identification label on occasion, and there was a problem that the high-mix low-volume production system could not be dealt with.

In view of the above, the group to which the present inventors belong proposes a heat-resistant printing substrate in which a layer in which an inorganic powder is retained by an aromatic polyamide is provided on one side of a heat-resistant substrate such as a polyimide film. (JP-A-3-175023). According to this, it is possible to easily apply a pattern of a variety of products in small quantities by easily applying a pattern through a commercially available resin-based ink ribbon and a thermal transfer printer and issuing an identification label at any time.

However, it has been found that the above specifications cannot cope with the miniaturization of the label size accompanying the downsizing of recent printed circuit boards and electronic parts. In other words, with the miniaturization of label size,
Higher density printing is required, and high-density printing was attempted on the heat-resistant printing base material of the above specifications, but thermal transfer errors such as ink spilling frequently occur, and there is a problem that a practical label cannot be formed. It has been found.

[0005]

DISCLOSURE OF THE INVENTION According to the present invention, a pattern can be applied at a high density by a thermal transfer method, a label can be issued on an occasional basis, and it is excellent in chemical resistance such as heat resistance, abrasion resistance and solvent resistance, and can be heated. The problem is to develop a heat-resistant printing substrate or label capable of imparting a thermal transfer pattern that can withstand treatment, solvent cleaning treatment, and wiping treatment.

[0006] In the above, a demand for a thermal transfer pattern having excellent chemical resistance such as heat resistance, scratch resistance, solvent resistance, etc., requires a label which can be used in a mounting process of a printed circuit board without providing a coating layer on the pattern. The purpose is to get.
That is, in the mounting process of the printed circuit board,
After the label is directly contacted with a solder bath such as a flow or reflow method at 300 ° C for 1 to 60 seconds, it is treated with a solvent such as trichloroethane or CFC-based or HCFC-based or alkaline cleaner-based CFC-based solvent or pure water. , Washed,
This is because it is necessary to prevent the ink that forms the pattern from being eluted or decomposed by the heating at that time, or to prevent the pattern function from disappearing and losing the label function in the subsequent processing, washing, and wiping steps. is there.

[0007]

According to the present invention, at least one kind of aromatic polyamide or polyimide is used as a binder to hold an inorganic powder in a sheet shape, and the surface roughness based on Ra is 0.01 to. The present invention provides a heat-resistant printing base material having an inorganic powder layer of 0.2 μm, and a label characterized by providing an ink pattern on the inorganic powder layer in the heat-resistant printing base material. .

[0008]

By using the inorganic powder layer having the above structure, a clear pattern can be provided at a high density without causing blurring even in a commercially available thermal transfer printer, and a label can be issued on occasion. In addition, by adding an ink receiving layer containing a cured or uncured UV-curable resin and using a heat-fixing ink, a thermal transfer pattern with excellent chemical resistance such as heat resistance, scratch resistance, and solvent resistance can be obtained. Can be formed.

[0009]

Exemplary heat-resistant printing substrate of the present invention is
An inorganic powder is formed into a sheet shape by using at least one kind of aromatic polyamide or polyimide as a binder, R
It has an inorganic powder layer having a surface roughness based on a of 0.01 to 0.2 μm. An example thereof is shown in FIG. Note that FIG. 1 shows an example of what is used as a label, in which 1 is a heat-resistant printing substrate made of the inorganic powder layer itself, and 2 is a pattern layer. In addition, 3 is an adhesive layer provided as needed, and 4 is an adherend.

The inorganic powder layer can be formed by using at least one kind of aromatic polyamide or polyimide as a binder to retain the shape of the inorganic powder in a sheet shape, and the inorganic powder layer in the present invention has a surface roughness of Ra. Based on 0.0
1 to 0.2 μm. With such a surface roughness, clear high-density printing by the thermal transfer method becomes possible.

The aromatic polyamide and polyimide to be used are not particularly limited, and those having appropriate thermoplasticity and curability may be used. Examples thereof include metaphenylene isophthalic acid type polyamide, paraphenylene terephthalic acid type polyamide, pyromellitic acid type polyimide, benzophenone tetracarboxylic acid type polyimide, 2,2-bis (3 ′, 4′-dicarboxyphenyl) hexafluoro. Examples thereof include propane-based polyimide, bismaleimide / diamine-based polyimide amine, nadic group- or acetylene group-containing polyimide, trimellitic acid-based polyamide imide, polyester imide, and the like, and those having excellent heat resistance are preferable. Two or more kinds of aromatic polyamide and polyimide may be used.

As the inorganic powder, an appropriate one may be used, and it can be appropriately determined according to the color and the like. By the way, white substances such as calcium carbonate, silica, titania, alumina, zinc white, zirconia, calcium oxide, mica, manganese oxide / alumina, chromium oxide / tin oxide, iron oxide, red substances such as cadmium sulfide / selenium sulfide, oxidation Cobalt, zirconia, vanadium oxide, chromium oxide
Blue substances such as divanadium pentoxide, black substances such as chromium oxide / cobalt oxide / iron oxide / manganese oxide and chromate, permanganate, zirconium / silicon / praseodymium, vanadium / tin, chromium / titanium / antimony Such as yellow, chrome oxide, cobalt chrome, alumina
Typical examples are green materials such as chromium, and pink materials such as aluminum / manganese and iron / silicon / zirconium. The particle size of the inorganic powder is 50 μm or less, especially 20 μm or less, especially 10 μm from the viewpoint of achieving the above-mentioned surface roughness.
The following are preferred.

The content of the inorganic powder in the inorganic powder layer is
From the point of achieving a surface roughness of 0.01 to 0.2 μm based on Ra, it is 10 to 120 g / m ² , especially 15 to 11
It is preferably 0 g / m ² , and particularly preferably ²⁰ to 100 g / m ² . The amount of the binder may be appropriately determined according to the shape-retaining property of the inorganic powder, and is generally 5% by weight or more, preferably 10-9.
It is set to 0% by weight, particularly 25 to 70% by weight. The inorganic powder layer may be mixed with a heat-resistant reinforcing base material such as fibrous material or other compound for obtaining the following composite form, within the range of maintaining the surface roughness.

In the present invention, the heat-resistant printing base material may be a sheet-like material having the inorganic powder layer positioned on the surface side, and thus can be formed in an appropriate form. For example, as shown in FIG. 1, the inorganic powder layer 1 itself is used, and as shown in FIG.
In the form of composite with 2, the inorganic powder layer 11 as illustrated in FIG.
Examples thereof include a form in which the ink receiving layer 13 is provided on the top and a form in which an adhesive layer is provided.

In the above-mentioned composite form, in addition to a method in which an inorganic powder layer is provided on a sheet-shaped heat-resistant reinforcing base material by a thermal lamination method or an extrusion coating method as shown in FIG. A method of impregnating or coating a solution or molten material for forming an inorganic powder layer, a method of interposing a sheet-shaped heat-resistant reinforcing base material in the inorganic powder layer, and a heat-resistant reinforcement of fibrous material in the inorganic powder layer. It may be appropriately formed by a method of mixing a base material.

Therefore, as the above-mentioned heat-resistant reinforcing base material, a suitable material such as a heat-resistant resin coating layer or film, heat-resistant fiber or heat-resistant cloth, heat-resistant paper or heat-resistant nonwoven fabric, metal foil, heat-resistant net or wire may be used. The physical properties of the heat resistant reinforcing base material may be appropriately determined according to the purpose of use.

Incidentally, examples of the heat-resistant resin include polyimide, polyetheretherketone, polyethersulfone, polyetherimide, polysulfone, polyphenylene sulfide, polyamideimide, polyesterimide, aromatic polyamide, polyparabanic acid, fluororesin, and epoxy resin. And so on. In addition, the heat resistant reinforcing base material used in combination may be subjected to necessary measures such as improvement in contrast with the applied pattern.

The thickness of the inorganic powder layer is 0.2-100 μm.
m, especially 1 to 80 μm is preferable. Its thickness is 0.2 μm
If it is less than 100 μm, the ink receiving power, ink retaining power or strength at the time of thermal transfer may be poor, and if it exceeds 100 μm, the pattern applied by melting due to heating tends to be flow-deformed.

The ink receiving layer provided on the inorganic powder layer, if necessary, is intended to improve the fixing property of the applied pattern. In the present invention, an ink receiving layer using a cured or uncured ultraviolet curable resin is preferable from the viewpoint of improving heat resistance, scratch resistance, solvent resistance, and other chemical resistance of the applied pattern. . By providing such an ink receiving layer, there is an advantage that the above-mentioned heat-resistant reinforcing base material having poor chemical resistance can be used.

For forming the ink receiving layer, one kind or two kinds are used.
It is possible to use one or more kinds of ultraviolet curable resins, and they can be formed as a layer of a cured state or an uncured body in an appropriate curing progress state. As the ultraviolet curable resin, those having excellent heat resistance, chemical resistance such as solvent resistance, and excellent abrasion resistance are preferably used, and examples thereof include a polyimide resin,
Epoxy resin, epoxy acrylic resin, urethane acrylic resin, polyester acrylic resin, acrylic ester resin, alkyd acrylic resin, silicone acrylic resin, polyene / polythiol type spirane resin, aminoalkyd resin, etc. To be

As the above-mentioned UV-curable resin, a commercially available product can sufficiently achieve the purpose. By the way, as the urethane acrylic resin, a reaction product of a polyester polyol and an isocyanate monomer or a prepolymer is reacted with a hydroxyl group-containing acrylate or methacrylate such as 2-hydroxyethyl (meth) acrylate or 2-hydroxypropyl (meth) acrylate. Examples thereof include those that have been made.

Examples of the polyester acrylic resin include reaction products of polyester polyol and the above-mentioned hydroxyl group-containing acrylate or methacrylate. Furthermore, examples of the acrylic ester resin include those represented by the following general formula.

[0023] (However, X ¹ , X ² , X ³ are hydrogen or a methyl group, R ¹ , R
² , R ³ is an alkylene group having 1 to 20 carbon atoms or an oxydialkyl group, and X ¹ , X ² , X ³ or R ¹ , R ² , R ³ may be the same or different. It may be. )

Any appropriate photopolymerization initiator may be used as the photopolymerization initiator to be added to the ultraviolet curable resin. Examples thereof include aromatic diazonium salts, aromatic halonium salts, aromatic onium salts, benzophenone compounds, benzophenone / amine compounds, acetophenone compounds, benzoin ether compounds, p-benzoylbenzyl chloride and the like. As the photopolymerization initiator, one kind or two or more kinds can be used depending on the kind of the ultraviolet curable resin used in combination, and the amount thereof is usually 0.1 to 20 parts by weight per 100 parts by weight of the ultraviolet curable resin. Parts, especially 0.2 to 15 parts by weight, particularly preferably 0.5 to 10 parts by weight.

The thickness of the ink receiving layer is 0.5 to 150 μm.
m, especially 1 to 100 μm, and particularly preferably 5 to 80 μm.
If the thickness is less than 0.5 μm, the ink receiving ability, ink retaining ability, or strength at the time of thermal transfer may be poor.
If it exceeds 50 μm, the pattern imparted by melting by heating tends to be flow-deformed.

The ink receiving layer may contain additives such as a heat resistant resin, an inorganic powder or a coloring agent.
The addition of the heat-resistant resin to the ink receiving layer is effective for improving the fixability of the pattern and the like, and the amount thereof is preferably the same as or less than that of the ultraviolet curable resin. Examples of the heat-resistant resin and inorganic powder to be used include those exemplified in the above inorganic powder layer.

The label of the present invention can be formed by applying an ink pattern to the inorganic powder layer on the heat-resistant printing substrate or the ink receiving layer thereon, and the ink for forming the pattern is appropriately selected. You may use the thing.
From the viewpoint of heat transfer pattern formation, which has excellent chemical resistance such as heat resistance, scratch resistance, and solvent resistance, the heat containing cured or uncured UV curable resin, heat-fusible binder, and colorant as components. Fixing agents are preferably used.

Conventional inks may be formed using a colorant and a hot melt binder. As the colorant, for example, an appropriate material such as an organic or inorganic pigment, carbon, or metal powder can be used. Examples of organic pigments include azo pigments, phthalocyanine pigments, triphenylmethane pigments, metal complex pigments, vat dye pigments, quinacridone pigments, isoindolinone pigments, and the like. Examples of the inorganic pigment include those exemplified as the inorganic powder in the above-mentioned inorganic powder layer.

Wax or polymer is generally used as the heat-meltable binder, and the kind thereof is not particularly limited. Examples of waxes that can be preferably used include paraffin wax, micro wax, paraffin wax such as polyethylene wax, beeswax,
Carnauba wax, natural waxes such as wood wax,
Higher alcohol waxes such as stearyl alcohol and palmityl alcohol, higher amide waxes such as stearamide, oleoamide and palmitoloamide, ester waxes such as Hoechst wax, butyl stearate, ethyl palmitate and myristyl stearate, stearic acid , Palmitic acid, behenic acid, myristic acid, capric acid, lauric acid, 1,20
-Examples include acid waxes composed of higher fatty acids such as eicosane diacid, and sorbitan derivatives. From the viewpoint of low-temperature fixability or short-time fixability, acid waxes are preferably used.

As the polymer for the heat-meltable binder, either a hydrophilic polymer or a hydrophobic polymer can be used, and a polymer having a softening point of 40 to 200 ° C. based on the ring and ball method is preferably used. The polymer is particularly preferably used in combination with wax. Examples of the hydrophilic polymer include gelatin, its derivatives, cellulose derivatives, natural products such as proteins such as casein and polysaccharides such as starch, and their derivatives, polyvinyl alcohol, polyvinylpyrrolidone, water-soluble polymers such as acrylamide polymers, Examples thereof include polymer latexes such as vinyl latex and urethane latex.

Examples of hydrophobic polymers that can be preferably used are polyvinyl butyral, polyvinyl formal,
Polyethylene, polypropylene, polyamide, ethyl cellulose, cellulose acetate, polystyrene, polyvinyl acetate, polyvinyl chloride, polyvinylidene chloride, vinyl chloride / vinyl acetate copolymer, ethylene / vinyl acetate copolymer, vinyl chloride / vinyl acetate / maleic acid terpolymer, ester Examples include rosin derivatives such as gum. In addition, various polymers may be used (US Pat. Nos. 3,062,674, 3,142,586,
No. 3143388, No. 3220844, No. 3
287289, No. 3411911, etc.).

Acrylic resins are preferably used in combination from the viewpoint of low-temperature fixability or short-time fixability. Examples of the acrylic resin include acid monomers such as acrylic acid and methacrylic acid, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, A single-component resin using an ester-based monomer such as isobutyl methacrylate, a multi-component resin (copolymer), or ethylene, styrene, or
Examples thereof include a copolymer system in which vinyl monomers such as vinyl acetate, vinyl chloride, butylene, isobutylene and butadiene are used in an amount of 20% by weight or less, preferably 15% by weight, particularly 10% by weight or less. The acrylic resin that can be preferably used in terms of the binder function and the like has a weight average molecular weight of 50,000 to 550,000, preferably 100,000 to 500,000, and particularly 200,000 to 400,000.

The use ratio of the colorant and the heat-fusible binder is
Although it is appropriately determined depending on the contrast with the heat-resistant printing base material and the thermal transfer pressure-bonding property, the heat-meltable binder 1 is generally used.
50-1000 parts by weight per 00 parts by weight, especially 80-8
00 parts by weight, especially 100 to 500 parts by weight of colorant are used.

The heat-fixing ink which can be preferably used for forming a heat transfer pattern having excellent chemical resistance such as heat resistance, abrasion resistance and solvent resistance is obtained by using the above-mentioned ink components, that is, the colorant and the heat-fusible binder. In addition, it can be obtained by using a cured or uncured ultraviolet curable resin in combination. Examples of the ultraviolet curable resin and the photopolymerization initiator include those exemplified in the above ink receiving layer, and the mixing ratio thereof can be in accordance with the above.

The ink or the heat fixing ink may contain a heat resistant resin. The addition of the heat-resistant resin to the ink is effective for improving the fixability of the pattern. Examples of the heat-resistant resin used include those exemplified in the above heat-resistant printing base material, and the compounding amount thereof is wax,
The amount is preferably equal to or less than that of the polymer or the ultraviolet curable resin.

The ink or the heat-fixing ink is prepared, for example, by heating and mixing one kind or two or more kinds of ink forming components in an appropriate mixing ratio such as a roll mill in an appropriate mixing ratio according to the purpose of use. It can be carried out by a method of forming a fluid such as a paste by a method of mixing with a suitable kneader such as a roll mill or a pot mill using a solvent if necessary.

An appropriate method can be adopted for mixing the ink-forming components, for example, a method of collectively mixing the ink-forming components or a method of appropriately dividing the ink-forming components into groups. The latter grouping method exhibits various advantages when forming an ink sheet such as a printing ribbon used for pattern formation by a thermal transfer method or the like.

The ink sheet is, for example, a coating method,
It can be formed by holding the ink or the heat fixing ink on a supporting base material such as a film or a cloth by an impregnation method or the like. In that case, an ink sheet of the heat fixing ink which can be preferably used for thermal transfer or the like is cured or A coating layer made of an uncured ultraviolet curable resin is arranged between an ink layer containing a heat-meltable binder and a colorant as components and a supporting substrate.

An example of the above-mentioned ink sheet in which the coat layer is arranged between the ink layer and the supporting substrate is shown in FIGS. 4 and 5. Reference numeral 21 is a coat layer, 22 is an ink layer, and 5 is a supporting base material. By using the ink sheet having such a structure, as shown in FIGS. 6 and 7, a layer made of a cured or uncured ultraviolet curable resin is formed on the ink layer 22 containing a heat-meltable binder and a colorant as components. The patterned layer 2 having as a coat layer 21 can be formed efficiently and stably at the same time.

The formation of the ink sheet having a structure having a coat layer between the ink layer and the supporting base material is carried out, for example, by providing the supporting base material with a coating layer made of a cured or uncured ultraviolet curable resin and then coating the coating layer. It can be carried out by a method of providing an ink layer on the layer via another intervening layer if necessary.

It has been described above that the heat-fixing ink may contain a heat-resistant resin, and thus the pattern formed may contain a heat-resistant resin. In that case, a coating is provided between the ink layer and the supporting substrate. In a layered ink sheet, such a heat-resistant resin may be blended in either or both of the coat layer and the ink layer. From the viewpoint of pattern fixability, it is advantageous that at least the coat layer contains a heat-resistant resin.

The thickness of the ink layer is generally 0.2 to 5 μm, preferably 0.4 to 4.5 μm, particularly 0.8 to 3.
5 μm is preferred. If the thickness is less than 0.2 μm, the hiding power may be poor, and if it exceeds 5 μm, the ink layer may be sheared and good thermal transfer may not be performed, and a good pattern may not be formed.

The thickness of the coat layer is 0.05 to 3 μm.
Is common, especially 0.08 to 2.5 μm, especially 0.
1-2 μm is preferable. If the thickness is less than 0.05 μm, the formed pattern may have poor heat resistance, chemical resistance such as solvent resistance, and scratch resistance, and if it exceeds 3 μm, it is sheared together with the ink layer and cannot be thermally transferred well. In some cases, a good pattern cannot be formed.

As the supporting base material in the ink sheet, a usual material such as a plastic film made of polyester, polyimide, fluororesin or the like, or a cloth made of fibers such as polyamide or polyester may be used. In order to improve the adhesion of the ink layer or coat layer, it is effective to undercoat the supporting substrate with wax or the like.

In FIGS. 4 and 5, 51 is an anti-sticking layer, and 52 in FIG. 5 is an easily peelable layer, which are provided as necessary. The anti-sticking layer is provided on the back surface (the side not having the ink layer) of the supporting substrate for the purpose of preventing the ink sheet from sticking during printing by a thermal transfer method or the like. The easy peeling layer is provided between the coat layer and the supporting base material, that is, the ink layer or the like in the supporting base material, for the purpose of facilitating peeling of the pattern forming component such as the ink layer from the supporting base material during printing by a thermal transfer method or the like. It is provided on the side surface. Further, in the present invention, an easy transfer layer may be provided on the surface on the ink layer side for the purpose of surely transferring and adhering the pattern forming component such as the ink layer to the adherend at the time of printing by the thermal transfer system or the like.

The anti-sticking layer, the easily peelable layer, and the easily transferable layer may be formed in a conventional manner by using known agents. Incidentally, examples of the anti-sticking layer forming agent include silicone resin, fluororesin, polyimide, epoxy resin, phenol resin, melamine resin, nitrocellulose, polyester, acrylic resin and the like. Examples of the agent for forming the easily peelable layer include wax, zinc stearate, chlorinated polyethylene, ethylene / vinyl acetate copolymer, polyester, polypropylene, polyisobutylene, polyvinyl alcohol, polyvinyl acetal, acrylic resin and the like. Examples of the easy-transfer layer forming agent include those exemplified as the components for forming the ink layer, and a composition having a high content of the heat-meltable binder is preferable.

In the present invention, the pattern to be applied to the inorganic powder layer of the heat resistant printing substrate or the ink receiving layer thereabove is arbitrary. An arbitrary pattern such as a print pattern, a picture pattern, or a bar code pattern may be provided. The pattern forming method is also arbitrary, and an appropriate forming method such as a coating method using a pattern forming mask and a forming method using a printer such as an XY plotter, a wire dot type, or an impact type can be adopted. A method which can be preferably applied is a thermal transfer method.

In particular, the pattern forming method using the thermal transfer printer and the ink sheet is preferable from the viewpoints of appropriate pattern forming efficiency and reasonable label issuing property. When an identification label is formed, it is preferable that good contrast or difference in color tone be formed between the heat-resistant printing substrate and the ink pattern. The label is
It is also possible to attach the heat-resistant printing substrate to an adherend and then form a pattern on the heat-resistant printing substrate.

From the viewpoints of chemical resistance such as heat resistance and solvent resistance, and scratch resistance, the preferred label of the present invention is a pattern provided by an ink receiving layer of a heat resistant printing substrate or / and a heat fixing ink. The ultraviolet curable resin in the above is cured by ultraviolet rays, and the curing treatment can be performed at an appropriate stage before being subjected to a process such as a solder flow or chemical cleaning.

Therefore, the curing treatment can be carried out in advance on the ink-receiving layer and / or the heat-fixing ink or coat layer before applying the pattern to the heat-resistant printing substrate, or the heat-resistant printing substrate. It can also be applied to the ink-receiving layer or / and the applied pattern after the pattern has been applied, and thus after the label has been formed. Further, even when the curing treatment is performed after the label is formed, it can be performed at an appropriate stage before and after attaching the label to the adherend.

In the case where the curing treatment is performed after the label is formed, the curing treatment of the ink receiving layer when the heat resistant printing substrate having the ink receiving layer is used may be the same as the curing treatment for the applied pattern. However, it may be performed before applying the pattern. An appropriate ultraviolet ray source can be used as the ultraviolet ray source for the curing treatment, and any general-purpose ultraviolet ray source such as a high pressure mercury lamp, a xenon lamp, a mercury vapor lamp or a carbon arc can be used.

As described above, the pattern, which is formed by after-curing the formed label or its applied pattern with ultraviolet rays as required, and which is covered with the top coat layer made of an ultraviolet curable resin, has a high heat resistance and a high resistance. It has excellent chemical resistance such as scratch resistance and solvent resistance, and when a heat-resistant printing substrate having an ink receiving layer is used, it is excellent due to its properties. Therefore, a pattern with a top coat layer can be formed simultaneously and on occasion with a commercially available thermal transfer printer or the like, and it is possible to avoid the need to separately laminate a coating tape layer on the ink pattern.

The heat-resistant printing substrate or label of the present invention comprises
If necessary, an adhesive layer for attaching to an adherend can be provided. The adhesive layer can be provided at an appropriate stage until the heat-resistant printing base material or label is attached to the adherend, and thus can be provided in advance before the heat-resistant printing base material is patterned to form a label. However, it can be provided after it is used as a label.

For forming the adhesive layer, an appropriate adhesive substance can be used, and generally, a rubber-based adhesive, an acrylic-based adhesive, a silicone-based adhesive, a vinyl alkyl ether-based adhesive, a polyvinyl alcohol-based adhesive. Organic materials such as polyvinylpyrrolidone-based adhesives, polyacrylamide-based adhesives, and cellulose-based adhesives are used.

The adhesive layer may be attached to the heat-resistant printing substrate or the label by an appropriate method such as a rolling method such as a calendar roll method or a sheet forming method such as a doctor blade method or a gravure roll coater method. May be carried out by an appropriate method such as a method of forming and transferring. The thickness of the attached adhesive layer can be determined according to the purpose of use, and is generally 1 to 500 μm, especially 2 to 300 μm, especially 3 to 100 μm.
It is assumed to be μm. It is preferable that the provided adhesive layer is covered with a separator or the like until the adhesive layer is temporarily attached to the adherend to prevent contamination and the like.

The heat-resistant printing substrate or label of the present invention comprises
For example, it is preferably used for various purposes such as giving identification marks such as barcodes to various articles such as ceramics, glass products, ceramic products, metal products, enamel products, resin products, and wood products, or providing other patterns. sell. In particular, it can be preferably used for product management of adherends that need to undergo a heating process, a cleaning process with a solvent, and a wiping process, such as a printed circuit board used in the mounting process. The adherend may be in any form, such as a flat form or a container form.

[0057]

According to the present invention, a clear pattern can be provided with high density without causing blurring even in a thermal transfer printer, and an arbitrary pattern can be provided on demand, and a necessary label is issued at any time. be able to. In the case of using an ink receiving layer or a heat-fixing ink that uses an ultraviolet curable resin, a heat transfer pattern having excellent chemical resistance such as heat resistance, scratch resistance, and solvent resistance can be formed. Does not disappear due to solder flow, solvent cleaning, or wiping,
Excellent in pattern preservation.

[0058]

【Example】

Example 1 50 parts of titania (parts by weight, the same applies hereinafter), 30 parts of calcium carbonate, 20 parts of talc, 30 parts of polymetaphenylene isophthalamide, and 10 parts of a thermoplastic polyimide having a softening point of 250 ° C. were N, N-dimethylacetamide 185. Knead with a roll mill uniformly in a roll mill to form a paste, which is cast on one side of a polyimide film with a thickness of 50 μm by the doctor blade method and dried to a thickness of 10 μm.
m, an inorganic powder layer having a surface roughness (Ra) of 0.05 μm is provided,
A 30 μm-thick acrylic adhesive layer containing a 2-ethylhexyl acrylate copolymer as a main component was attached to the other surface, which was covered and protected with a separator to obtain a heat-resistant printing substrate.

On the other hand, 40 parts of paraffin wax having about 20 carbon atoms, 40 parts of carnauba wax, 10 parts of ethylene / vinyl acetate copolymer and 10 parts of amide wax were uniformly mixed with 200 parts of toluene by a roll mill, and the mixture was homogenized. The dispersion is applied by a gravure coater to a back surface of a 6 μm-thick polyester film with a sticking prevention layer to a thickness of 0.5 μm, dried, and an ink layer with a thickness of 2 μm is provided on the ink sheet. Got The ink contains carbon 1
A mixture of 00 parts, 20 parts of paraffin wax, 20 parts of carnauba wax, 10 parts of ethylene / vinyl acetate copolymer, and 50 parts of tetrafluoroethylene resin was uniformly mixed with 200 parts of toluene by a roll mill.

Next, a bar code pattern is formed on the inorganic powder layer of the heat-resistant printing base material using the above-mentioned ink sheet through a commercially available thermal transfer bar code printer (Duraprinter SR, the same applies below). Got the label.

Example 2 100 parts of titania and 75 parts of polyetherimide were mixed with N, N.
-A 175 parts of dimethylacetamide was uniformly kneaded in a roll mill to form a paste, which was cast on a separator by a doctor blade method and dried to obtain a thickness of 75 μm and a surface roughness (Ra) of the printing side of 0.05 μm. A white polyetherimide film (inorganic powder layer) is provided on one side with a 5 μm thick ink receiving layer, and on the other side with a 20 μm thick acrylic adhesive layer containing a butyl acrylate copolymer as a main component. Then, it was covered and protected with a separator to obtain a heat resistant printing substrate. The ink receiving layer is
A liquid prepared by dissolving 100 parts of a bisphenol A type liquid epoxy resin and 3 parts of allyl diazonium salt in 100 parts of methyl ethyl ketone with a disper was cast by a doctor blade method and dried.

On the other hand, a solution prepared by dissolving 100 parts of bisphenol A type liquid epoxy resin and 3 parts of allyl diazonium salt in 100 parts of methyl ethyl ketone with a disperser was applied to a gravure coating machine to obtain a thickness with a sticking prevention layer and an easily peelable layer. A polyester film having a thickness of 6 μm is coated on the back surface with a thickness of 0.8 μm, dried, and then a thickness of 2 according to Example 1 is applied.
An ink layer having a thickness of μm was provided to obtain an ink sheet having a heat fixing ink layer.

Next, a bar code pattern is formed on the ink receiving layer of the heat resistant printing base material through the commercially available thermal transfer bar code printer using the above ink sheet, which is 350 mJ in an ultraviolet irradiation furnace. A label was obtained by treating with / cm ² .

Comparative Example 1 The printed surface has a surface roughness (Ra) of 0.5 μm and a thickness of 50 μm.
An adhesive layer was provided on the back surface of the white polyimide film of Example 1 according to Example 1, and a commercially available wax-based ink sheet was used to form a bar code pattern on the printed surface according to Example 1 to obtain a label.

Comparative Example 2 The printed surface has a surface roughness (Ra) of 0.3 μm and a thickness of 50 μm.
An adhesive layer was provided on the back surface of the white polyetherimide film of Example 1 according to Example 1, and a commercially available resin-based heat-fixing ink type ink sheet was used on the printed surface of Example 1.
A bar code pattern was formed according to the above to obtain a label.

Evaluation Test The appearance of the labels obtained in Examples and Comparative Examples when printed with various line widths was judged according to the following criteria. ○: A clear pattern with no blurring, etc. △: Blurredness is recognized in some places, but legible. ×: Inability to read due to blurring, etc.

The above results are shown in the following table.

In the label obtained in Example 2, the separator was peeled off and pressure-bonded to the glass / epoxy substrate via the adhesive layer, and acetone, toluene, trichloroethane, Freon-113, HCFC solvent, or Cleansul-750H ( Even when the pattern surface of the label is wiped with a non-woven fabric impregnated with a solvent consisting of the product name, manufactured by Kao Corporation,
The pattern showed a good residual state without any change. Also, when the glass / epoxy substrate for pressure bonding of the label was subjected to the soldering process at 260 ° C. for 5 seconds, the pattern showed a good residual state without any change.

Furthermore, the glass / epoxy substrate on which the label obtained in Example 2 was pressure-bonded was subjected to a soldering process in accordance with the above, and then the pattern surface of the label was wiped with a solvent-impregnated non-woven fabric to leave the pattern in a remaining state. As a result, the pattern did not change regardless of which solvent was used.
Therefore, it can be seen that the ink pattern and the inorganic powder layer are not eluted and decomposed by heating in the soldering process or treatment with a solvent, the applied pattern is well preserved, and the label function is maintained.

[Brief description of drawings]

1 is a cross-sectional view of an example label

FIG. 2 is a cross-sectional view of another heat-resistant printing substrate example.

FIG. 3 is a sectional view of still another heat-resistant printing substrate example.

FIG. 4 is a sectional view of an example of heat fixing ink.

FIG. 5 is a cross-sectional view of another heat fixing ink example.

FIG. 6 is a cross-sectional view of another label example.

FIG. 7 is a cross-sectional view of still another label example.

[Explanation of symbols]

1: Heat resistant printing base material (inorganic powder layer) 11: Inorganic powder layer 12: Heat resistant reinforcing base material 13: Ink receiving layer 2: Pattern layer 3: Adhesive layer 4: Adherend

Front page continuation (72) Inventor Okazaki Isao 1-2-2 Shimohozumi, Ibaraki City, Osaka Prefecture Nitto Denko Corporation (72) Inventor Satoshi Ito 1-2 1-2 Shimohozumi, Ibaraki City, Osaka Nitto Electric Works Co., Ltd. (72) Inventor Yasuo Kuramoto 1-2-2 Shimohozumi, Ibaraki City, Osaka Prefecture Nitto Electric Works Co., Ltd. (72) Makoto Honda 1-2-1 Shimohozumi, Ibaraki City, Osaka Prefecture Nitto Denko Within the corporation

Claims (6)

[Claims] 1. A surface roughness based on Ra of 0.01 to 0.2, which is obtained by using at least one kind of aromatic polyamide or polyimide as a binder to hold an inorganic powder in a sheet shape.
A heat-resistant printing substrate having an inorganic powder layer of μm. 2. The heat-resistant printing substrate according to claim 1, further comprising an ink receiving layer containing a cured or uncured ultraviolet curable resin as a component on the inorganic powder layer. 3. The heat resistant printing substrate according to claim 1, wherein the inorganic powder layer is combined with a flexible heat resistant reinforcing substrate. 4. The heat resistant printing substrate according to claim 1, which has an adhesive layer. 5. A label provided with an ink pattern on the inorganic powder layer or the ink receiving layer thereon in the heat-resistant printing substrate according to any one of claims 1 to 4. 6. A thermal transfer pattern of a heat-fixing ink, wherein the ink pattern has a coat layer containing a cured or uncured ultraviolet curable resin on an ink layer containing a heat-meltable binder and a colorant as components. The label according to claim 5, wherein: