JPH05126651A - Temperature inspecting sheet - Google Patents

Abstract

PURPOSE:To inspect and measure the temperature without limitation by the shape and material of a hot plate by peelably overlapping a color sheet having a heat transfer layer containing a sublimating dye and a coloring sheet having a coloring layer made of dye dyeing resin. CONSTITUTION:A color sheet 3 constituted of a sheet-like base 1 and a heat transfer layer 2 and a coloring sheet 6 constituted of a sheet-like base 4 and a coloring layer 5 are overlapped peelably between the surface of the heat transfer layer 2 and the surface of the coloring layer 5 to form a stratiform temperature inspecting sheet. The heat-resistant resin and paper such as polyphenylene sulfide in addition to plastic polyethylene terephtalate are used for the material of the base 1. The heat transfer layer 2 carries the dye via optional binder resin, and the sublimating disperse dye used for a heat transfer sheet can be used. A material having a good adhesive property to the base 4, not deposited on the sheet 3, and not impairing the internal moventent of the dye, e.g. polyester resin, is used for the coloring layer 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature inspection sheet for detecting temperature unevenness of a heating surface of a hot plate such as a roll laminator or a hot press.

[0002]

2. Description of the Related Art Conventionally, a thermocouple thermometer has been used as a means for inspecting such temperature unevenness of the surface temperature of a hot plate or the like. The thermocouple thermometer is made by joining two wires made of different kinds of metal materials, and uses thermoelectromotive force to measure heat and temperature. That is, it is the temperature difference that can be measured by the thermocouple thermometer, and the temperature can be measured by keeping the temperature of one contact constant.

[0003]

However, in the measurement by the thermocouple thermometer, only the temperature of the point portion on the surface of the hot plate can be measured, and it is impossible to grasp the temperature state of the entire hot plate surface in a complete form. It was impossible. Further, the thermocouple thermometer generally has a slow response and is liable to cause a measurement error unless the thermal contact with the object is sufficiently improved. further,
If there is a temperature gradient along the thermocouple wire of the thermocouple thermometer, a parasitic thermoelectromotive force due to the inhomogeneity of the thermocouple wire is generated, which is one of the causes of further error.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and is provided with a color sheet provided with a thermal transfer layer containing a sublimable dye and a coloring layer made of a dye-dyeable resin. The color-developing sheet is releasably superposed on the surface of the thermal transfer layer and the surface of the color-developing layer, which is a means for solving the above problems.

[0005]

When the color sheet side surface of the temperature inspection sheet according to the present invention is made to face the heat plate surface and heat is applied to the heat transfer layer of the color sheet, the sublimable dye forming the heat transfer layer is sublimated, and the color is developed. Color shifts to the layer. The high temperature portion of the hot plate is dark and the low temperature portion of the hot plate is light. Therefore, the temperature inspection sheet of the present invention can represent the temperature unevenness of the hot plate as color unevenness of the image receiving sheet. That is, it is possible to detect the temperature of the entire surface of the hot plate at the same time, and it is possible to perform measurement detection with extremely few measurement omissions and measurement errors.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a sectional view of the temperature inspection sheet of the present invention.

FIG. 1 shows an embodiment of a temperature inspection sheet according to the present invention. The temperature inspection sheet comprises a color sheet 3 and a coloring sheet 6. The color sheet 3 comprises a first sheet-shaped substrate 1 and a thermal transfer layer 2,
The coloring sheet 6 is composed of the second sheet-shaped substrate 4 and the coloring layer 5. The color sheet 3 and the color-developing sheet 6 formed in this manner are releasably superposed on the surface of the thermal transfer layer 2 and the surface of the color-developing layer 5 to form one layered temperature inspection sheet. To form.

[0008] Therefore, as the material of the first sheet-shaped substrate 1, polyethylene terephthalate, which is the most common plastic, can be mentioned. However, a highly heat-resistant resin such as polyphenylene sulfide, aramid, or polyimide, and paper are also used. Be done. The material of the first sheet-shaped base material 1 is preferably one having high mechanical strength such as tensile strength and heat resistance sufficient to withstand the temperature of an ordinary hot plate, and is generally plastic, paper or the like. Flexible thin sheets are used. The thickness of the first sheet-shaped substrate 1 is usually 1 to 60 μm, preferably about 2 to 20 μm.

Further, the first sheet-shaped substrate 1 as described above
The thermal transfer layer 2 formed on is a layer in which a dye is carried by an arbitrary binder resin. As the dye to be used, any of the sublimable disperse dyes used in conventionally known heat transfer sheets can be effectively used in the present invention.
It is desirable to have a molecular weight of about 50 to 400. Furthermore, this dye is selected in consideration of thermal sublimation temperature, hue, weather resistance, stability in binder resin, and the like, and specific examples include the following. As a red dye, M
S Red G, Macrolex Red Violet
t R, Ceres Red 78, Samaron R
ed 11BSL, SK Rubin SEGL and the like,
Further, examples of yellow dyes include Horn Brilliant Yellow S-6GL, PTY-52, and Macrolex Yellow S-6G, and examples of blue dyes include Kayaset Blue 714, Waxolin Blue AP-FW, and Holon. Brilliant Blue SR, MS Blue 100, Daito Blue No. 1 etc. are mentioned. However, for the purposes of the present invention, a monocolor image is sufficient for the required image and the above dye is used in a single color. Further, a plurality of dyes having different hues having different thermal sublimation temperatures may be mixed and used, and in this case, the temperature unevenness can be detected not only by the shade of the color but also by the difference in the hue.

The dye is usually present in the thermal transfer layer in an amount of about 5 to 90% by weight, preferably about 10 to 70% by weight, depending on the sublimation temperature of the dye and the covering power in the developed state. It is a thing. Further, as the binder resin for supporting the sublimable disperse dye as described above, a resin having high heat resistance, which does not hinder the migration of the dye when heated, is selected. Be done. (1) Cellulose-based resin Ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxycellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, etc. (2) Vinyl resin Polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, polyvinyl pyrrolidone, polyester, polyacrylamide and the like. As described above, the thermal transfer layer 2 of the color sheet 3 of the present invention is basically formed of the above-mentioned materials, but may also contain various conventionally known additives as required.

The thermal transfer layer 2 is preferably prepared by adding the above-mentioned dye, binder resin and other optional components to a suitable solvent to dissolve or disperse each component to prepare a coating for forming the thermal transfer layer. It is formed by coating and drying on the first sheet-shaped substrate 1.

Further, the thermal transfer layer 2 in the color sheet 3
The color-developing layer 5 formed on the side surface is a layer that receives the dye transferred from the color sheet 3 due to heat, can sufficiently hold the color developer, and can adhere to the second sheet-shaped substrate 4. It is preferable that it has good properties, and that it does not fuse with the color sheet 3 upon heating and does not hinder the transfer of the dye transferred from the color sheet 3 to the inside. Specifically, polyester resin, modified EVA resin, acrylic resin, maleic anhydride resin, urethane resin, polyvinyl alcohol resin, vinyl acetate resin, EVA resin, styrene resin, stellene copolymer resin (For example, butadiene-styrene copolymer resin, acrylonitrile-styrene copolymer resin, acrylonitrile-butadiene-styrene copolymer resin, chlorinated polyethylene-acrylonitrile-styrene copolymer resin, methyl methacrylate-butadiene-styrene copolymer Resin, methyl methacrylate-styrene copolymer resin, etc.), rubber resin, silicone resin, cellulose resin, natural rosin resin,
Amino resin, nylon resin, polycarbonate resin, ethene-vinyl acetate-vinyl chloride copolymer resin,
Polymethylpentene resin, ionomer resin, acetal resin, phenol resin, epoxy resin, melamine resin, alkyd resin, etc. can be used. Further, among the above binders, a resin having a low glass transition temperature is preferable from the viewpoint of color developability, and examples of such a resin include polyester resins, modified EVA resins, acrylic resins, maleic anhydride resins, urethane resins. Resin and the like can be mentioned.

That is, the coloring layer 5 is not particularly limited as long as it is dyed well with a sublimable disperse dye and does not cause fusion, blocking, or sticking with the color sheet 3 during thermal transfer. Further, as the resin component constituting the color forming layer 5, a cross-linking type is preferable among them, and a composition of a dye-dyeing resin and a cross-linking agent is preferable.

Specific examples of the dye-dyeing resin include polyester resin, polyacrylic ester resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, vinyl toluene acrylate resin, polyurethane resin, polyamide resin, urea resin, Examples thereof include polycaprolactone resin, styrene-maleic anhydride resin, polyvinyl chloride resin and polyacrylonitrile resin. These resins can be used alone or in a mixture or a copolymer.

Specific examples of the cross-linking agent include a reaction-curable silicone oil in the case of a thermosetting type, for example, one obtained by curing an amino-modified silicone oil and an epoxy-modified silicone oil, and a photocurable type. In the case, a photocurable silicone oil or a polyfunctional monomer or a polyfunctional oligomer having a (meth) acryloyloxy group may be mentioned, and more preferably, a polyfunctional monomer or a polyfunctional oligomer having a (meth) acryloyloxy group. Is. These are preferable in terms of productivity because ultraviolet rays, which are easy to handle, can be used as active energy rays and can be cured in a very short time.

Specific examples of such monomers or oligomers include polyether (meth) acrylates synthesized from 1,2,6-hexanetriol / propylene oxide / acrylic acid, trimethylolpropane / propylene oxide / acrylic acid; Adipic acid / 1,6
A polyester (meth) acrylate synthesized from hexanediol / acrylic acid, succinic acid / trimethylolethane / acrylic acid, etc .;

Triethylene glycol diacrylate,
Hexapropylene glycol diacrylate, neopentyl glycol diacrylate, 1,4-butanediol dimethacrylate, 2-ethylhexyl acrylate, tetrahydrofurfuryl acrylate, 2-hydroxyethyl methacrylate, ethyl carbitol acrylate, trimethylolpropane triacrylate, pentaerythritol. (Meth) such as tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, 2,2-bis (4-acryloyloxydiethoxyphenyl) propane, 2,2-bis (4-acryloyloxypropoxyphenyl) propane Acrylate or polyol (meth) acrylate;

Diglycidyl etherified bisphenol A
/ Epoxy (meth) acrylates such as allyl acid, diglycidyl etherified polybisphenol A / acrylic acid, triglycidyl etherified glycerin / acrylic acid:
γ-butyrolactone / N-methylethanolamine / bis (4-isocyanatocyclohexyl) methane / 2-hydroxyethyl acrylate, γ-butyrolactone / N
-Amidourethane (meth) acrylate such as methylethanolamine / 2,6-tolylene diisocyanate / tetraethylene glycol / 2-hydroxyethyl acrylate;

Urethane acrylates such as 2,6-tolylene diisocyanate diacrylate, isophorone diisocyanate diacrylate and hexamethylene diisocyanate diacrylate; spiro acetal acrylates synthesized from diallylidene pentaerythritol / 2-hydroxyethyl acrylate; epoxidized butadiene Examples include acrylated polybutadiene synthesized from / 2-hydroxyethyl acrylate, and these monomers and oligomers are formed alone or in a mixed system of two or more kinds.

Among the above-mentioned monomers and oligomers, the following general formula (1),

[0021]

[Chemical 1]

[In the formula, n is an integer of 1 to 4, and at least three X are represented by the general formula: CH ₂ ═CH—COO—R ₁ —
(In the formula, R ₁ represents a single bond, an alkylene group having 1 to 8 carbon atoms or a polyoxyalkylene group having an alkylene group having 1 to 8 carbon atoms.),
The remainder is an alkyl group having 1 to 8 carbon atoms, a hydroxyl group, an amino group, a formula: — (OR ₂ ) _m —H (wherein R ₂ is a carbon atom of 1
~ 8 represents an alkylene group, and _m is a positive integer. )
A group represented by the formula: — (OR ₂ ) _m —OH (wherein R ₂ and _m have the same meanings as described above), or a group represented by the formula: — (OCOR ₂ ) _m —H (wherein R ₂ and _m have the same meaning as defined above.). ] A compound represented by, for example, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tripentaerythritol pentaacrylate, tripentaerythritol hexaacrylate, tripentaerythritol heptaacrylate, the following general formula ( 2),

[0023]

[Chemical 2]

(Wherein n is a positive integer from 1 to 10 and X'is optionally -OH or -OCOCH = CH ₂ ), polybisphenol A type polyacrylate, for example, diglycidyl ether. Bisphenol A diacrylate, Epicoat # 1001 (n = 3, Shell Co.) diacrylate, or the like, or the following general formula (3):

[0025]

[Chemical 3]

(Wherein X ₁ , X ₂ , ..., X _n are the same or different alkylene groups having 6 or less carbon atoms or the structure in which one hydrogen atom thereof is substituted with a hydroxyl group, and n is An integer of 0 to 5), for example, 2,2
-Bis (4-acryloyloxydiethoxyphenyl)
Propane, 2,2-bis (4-acryloyloxydipropoxyphenyl) propane, and the like are particularly preferable cross-linking agents when they use ultraviolet rays as active energy rays, because they have very good quick-drying properties in air.

The above-mentioned monomers and oligomers are used, and a photopolymerization initiator is necessary for causing a crosslinking reaction by ultraviolet rays. These cross-linking agents are used to improve the releasability of the color forming layer 5. If necessary, a releasant may be added to the dyeing resin and the cross-linking agent to further improve the releasability. Is also good. Specific examples of the release agent include solid wax, fluorine-based, silicon-based, and phosphoric acid ester-based surfactants. If necessary, inorganic fine particles such as silica and talc, organic fine particles such as polyethylene and polypropylene, an antistatic agent, an ultraviolet absorber, and a light stabilizer may be added to the color forming layer 5.

As the method for forming the color-forming layer 5, it is possible to dissolve or disperse the above resin composition in a solvent and to easily form it by using a general coating agent coating method or a gravure printing method. it can. Such a coloring layer 5
The thickness is not particularly limited, but is preferably about 1 to 20 μm, for example.

Further, since the color forming layer 5 is heated while being in contact with the thermal transfer layer 2, the above-mentioned interface is formed on the interface between the color forming layer 5 and the thermal transfer layer 2 so that the color forming layer 5 and the thermal transfer layer 2 are not fused by heat. It is preferable to impart releasability as described above. The part that imparts releasability may be the surface of the thermal transfer layer 2, the surface of the color forming layer 5, or both. When the release property is given to the side of the coloring layer 5,
Examples thereof include a method of mixing or dissolving a release agent in the entire coloring layer 5, a method of forming the coloring layer 5 using a resin having releasability, and the like. As the thermal release agent, in addition to the above,
For example, silicone oils, cured silicone oils, silicone compounds such as silicone resins and silicone modified resins, fluorine compounds, long-chain alkyl compounds, waxes, phosphate ester surfactants and the like are used. These thermal release agents can be distributed throughout the color forming layer 5 by mixing or dissolving them in the resin for forming the color forming layer 5 and then applying them. Further, as the thermal release agent, one having a large specific gravity is used so as to be sunk toward the side closer to the second sheet-shaped base material 4 when the coloring layer 5 is formed, or the affinity between the thermal release agent and the second sheet-shaped base material 4 is increased. And the affinity between the thermal release agent and the resin for forming the color forming layer 5 is utilized to move the thermal release agent to a position closer to the second sheet-shaped substrate 4 or the like. A layer of a thermal mold release agent can be provided on the side that becomes the surface of the color forming layer 5.

Therefore, in order to provide the color forming layer 5 on the second sheet-shaped substrate 4, the color forming layer 5 forming resin, preferably the color forming layer 5 forming resin and a thermal release agent are kneaded together with a solvent or a diluent. Then, the composition for forming the color-developing layer 5 may be provided on the second sheet-shaped substrate 4 by an appropriate printing method or coating method. If necessary, a release agent, an antioxidant, an ultraviolet absorber or the like may be added to the composition for the color forming layer 5 in an arbitrary amount. Further, the second sheet-shaped substrate 4 used here may be any material to which the color forming layer 5 can be adhered, and for example, general paper, plastic sheet or the like is used.

Further, in the temperature inspection sheet, the surface of the coloring layer 5 after transfer and the thermal transfer layer 2 containing the sublimable disperse dye.
In addition to the thermal release agent used for preventing fusion between the color transfer sheet 3 and the thermal transfer layer 2, the peelability between the color forming layer 5 and the thermal transfer layer 2 is also important. If the peeling is extremely easy, there is a problem that the thermal transfer layer 2 is peeled from the color forming layer 5 before the transfer, and if the peeling is extremely difficult, the thermal transfer layer 2 and the color forming layer 5 are difficult to peel during the transfer. And may not be peeled off partially or entirely. Such peelability is not only affected by the magnitude of the adhesive strength between the thermal transfer layer 2 and the color forming layer 5, but rather, the thermal transfer layer 2 and the first sheet-shaped substrate 1 or the color forming layer 5 is rather affected.
And the balance of the adhesive force between the second sheet-shaped substrate 4 is affected. Therefore, in order to secure appropriate releasability between the thermal transfer layer 2 and the color forming layer 5, a method of providing the release layer 7 between the thermal transfer layer 2 and the color forming layer 5 or a method of providing the thermal transfer layer 2 itself with releasability. Can be mentioned. As the method for providing the release layer by the method of 1), for example, a method of applying a release material such as an acrylic resin, a silicone resin, a fluorine resin to form the release layer 7 or a method similar to the above-mentioned color forming layer 5 is used. Preferably, it may be formed as a layer having a thickness of about 10 ⁻⁵ to ⁵ μm.
The other method is performed by mixing a thermal release agent in the color forming layer 5 and the thermal transfer layer 2. The methods of and can be used alone or in combination. Further, the color sheet 3 and the color-developing sheet 6 which are formed in such a state that the respective adhesive strengths of the thermal transfer layer 2 and the first sheet-shaped base material 1, and the color-developing layer 5 and the second sheet-shaped base material 4 are well balanced are separately provided. It is also possible to prepare the above and use them as a temperature inspection sheet by simply stacking them without integrating them.

Therefore, the temperature inspection sheet according to the present invention is
When the surface of the temperature inspection sheet on the color sheet 3 side is opposed to the surface of a hot plate such as a hot press and heat is applied to the thermal transfer layer 2 of the color sheet 3, the sublimable dye in the thermal transfer layer 2 sublimes, This is transferred to the color forming layer 5 to cause color development. The high temperature portion of the hot plate is dark and the low temperature portion of the hot plate is light. Therefore, according to the temperature inspection sheet of the present invention, the temperature unevenness on the surface of the hot plate can be represented as the color unevenness of the coloring sheet 6. That is, a color image having continuous gradation like a photograph can be directly obtained in a short time from the heat signal from the heating plate. Further, the surface temperature of the hot plate can be inspected according to the desired position and the desired shape without being restricted by the shape and material of the hot plate to be measured.

Therefore, conventionally, the temperature unevenness on the hot plate surface is inspected by the point measurement by the thermocouple thermometer, and the temperature condition on the hot plate surface cannot be grasped as a whole due to measurement omission or measurement error. However, the temperature inspection sheet according to the present invention makes it possible to grasp the temperature condition of the entire surface of the hot plate, and it is possible to significantly reduce measurement omissions and measurement errors.

[0034]

According to the temperature inspection sheet of the present invention,
The temperature unevenness on the surface of a hot plate such as a roll laminator or hot press can be represented as the color unevenness of the coloring layer. Further, it is possible to perform the temperature inspection measurement of the hot plate surface according to a desired position and a desired shape without being restricted by the shape and material of the hot plate to be measured. Therefore, the heat signal from the hot plate can be directly obtained as a color image having continuous gradation like a photograph, and the state of the hot plate surface temperature can be grasped as a whole. Furthermore, measurement omissions and measurement errors can be significantly reduced, which can contribute to product production efficiency and product quality improvement.

[Brief description of drawings]

FIG. 1 is a sectional view of a temperature inspection sheet according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st sheet-shaped base material 2 Thermal transfer layer 3 Color sheet 4 2nd sheet-shaped base material 5 Color development layer 6 Color development sheet 7 Release layer

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kazuhiko Sukufu 20-1 Miyukicho, Otake City, Hiroshima Prefecture Mitsubishi Rayon Co., Ltd. Central Research Laboratory

Claims (1)

[Claims] 1. A color sheet provided with a thermal transfer layer containing a sublimable dye and a color sheet provided with a color forming layer made of a dye-dyeable resin can be peeled off from each other on the surface of the thermal transfer layer and the surface of the color forming layer. A temperature inspection sheet, which is characterized by being overlaid.