JPS63134288A - Thermal transfer recording material - Google Patents

Abstract

PURPOSE:To reproduce a dot configuration of a heating element with fidelity by composing a thermally melting type coloring transfer layer of two colorless thermally melting layers containing a reactive plasticizer and one coloring transfer layer containing a catalytic crosslinking accelerator and sandwiched between said two layers as a substrate. CONSTITUTION:When printing is effected by using this thermal transfer recording medium, receiving the heat of a heating element heated with a desired dot configuration from the rear surface of a substrate, first and third layers, which are thermally melting layers, are melted with desired dot configurations. At this time, since a catalytic crosslinking accelerator mixed in advance in the second layer, namely, a coloring transfer layer acts on a reactive plasticizer mixed in the first and third layers, the reactive plasticizer reacts repectively in the interfaces between the first and second layers and between the second and third layers to increase crosslinking viscosity. The dot configurations transferred to an image receiving paper due to above-described phenomenon reproduce the dot configuration of the heating element that are actually heated with fidelity.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is a method in which a heat-melting colored transfer layer of a specific hue is divided into areas on a single layer of a support such as a sheet-like substrate or a ribbon-like substrate. Alternatively, the present invention relates to a thermal transfer recording material comprising a line type or serial type support on which heat-melting colored transfer layers of the same hue are continuously formed.

[Conventional technology and its problems] In recent years, thermal transfer recording methods using thermal heads have become noiseless, can print in color, and are relatively inexpensive devices.
It is rapidly becoming popular due to its advantages such as being compact and easy to maintain. However, this printing method has a fatal drawback in that the reproducibility of fine dots is poor. That is, by heating from the back surface of the base film, the heat-melting colored transfer layer provided on the base film is partially melted and fixed onto the image receiving paper. However, since the dots that make up the pattern go through a process of being melted once, the dots have a shape that is significantly different from the theoretical dot shape of the heating element. Therefore, it has been desired to develop a heat-sensitive support with excellent reproducibility of fine dots.

This invention was made in view of these points, and is a thermal transfer recording material that makes it possible to faithfully reproduce the dot shape of a heating element, which was difficult to do with conventional supports used in thermal transfer recording systems. It provides:

[Means for solving the problem] A heat-melting colored transfer layer having a 3 m structure in which a heat-melting layer 2 colored transfer layer and a heat-melting layer are laminated in sequence on a support, and each of the heat-melting This thermal transfer recording material is characterized in that a reactive plasticizer is added to the layer, and a crosslinking accelerator for the reactive plasticizer is added to the colored transfer layer.

That is, the thermal transfer recording material of the present invention is preferably configured as follows, for example. A heat-melted layer containing a reactive plasticizer is provided on the support to a thickness of 0.2 to 1.2 μm. A colored transfer layer containing a catalytic crosslinking promoter that promotes crosslinking of the reactive plasticizer during heating is placed on this heat-melted layer.
The layers are laminated to a thickness of 2 to 0.5 μm. Furthermore, a layer having the same structure as the first layer containing a reactive plasticizer is laminated on the colored transfer layer to a thickness of 1 to 2.5 μm.

Here, the catalyst crosslinking promoter used in the present invention is as follows:
Methyl ethyl ketone peroxide, cyclohexanone peroxide, 3.3.5-trimethylcyclohexanone peroxide, acetylacetone peroxide, 1.1
-bis(t-butylperoxy)3.3.5-trimethylcyclohexanone, 1.1-bis(t-butylperoxy)cyclohexane2.2-bis(t-butylperoxy)octane, cumene hydroperoxide, Dicumyl peroxide, decanoyl peroxide, lauroyl peroxide, 3.5.5-trimethylhexanoyl peroxide, benzoyl peroxide, t-butyl peroxide (2-ethylhexanoate), t-butyl peroxide 3 .5゜5-trimethylhexanoate, t-
Organic peroxides such as butyl peroxybenzoate can be used. The amount of the crosslinking accelerator to be added to the colored ink is desirably 2 to 201%. As the reactive plasticizer added to the heat-melted layers of the first and third layers, monomers such as trimethylolpropane trimethacrylate and tetraethylene glycol dimethacrylate, or low-molecular-weight polyesters can be used. The additive layer preferably has a content of 5 to 15%. 11th! ! , 311th
The heat-melting layer constituting the heat-melting layer is made of a heat-melting substance such as wax or polyamide, and a binder resin consisting of IIM, and the same materials as those commonly used can be used. The colored transfer layer constituting the 21st layer is composed of a pigment and a binder resin.

[Function] When printing is performed using the thermal transfer recording material according to the present invention, the 111th heat-melting layer and the third layer receive heat from the heating element that generates heat from the back surface of the support in a desired dot shape. The heated melt layer melts into a desired dot shape. At this time, the catalytic crosslinking promoter mixed in advance into the 21st colored transfer layer acts on the reactive plasticizer mixed into the 111th and 311th layers, thereby causing the 1st layer and the 211th! The reaction crosslinking viscosity of the reactive plasticizer increases at the interface of 1 and the interface between the second layer and the third layer. The shape of the dots transferred to the image receiving paper through this development faithfully reproduces the shape of the dots of the heating element that actually generates heat.

[Example code] Examples of the present invention will be described below.

A material consisting of the following composition 1 was printed on a polyester film with a thickness of 5.7 μm by gravure printing to a dry thickness of 1 μm.
Coat it so that it looks like this. A material having the following composition 2 is coated thereon so that the dry thickness is 0.5 μm. Finally, a material of Composition 1 was coated to a dry thickness of 2 μm to obtain a thermal transfer recording material of Example.

Composition 1 Candeka wax 80 heavy ffi parts ethylene/vinyl acetate copolymer nitrocellulose 5 trimethylolpropane trimethacrylate IPA
75 Triol 75 Composition 2 Ethylene/vinyl acetate copolymer 25 Part by weight Carbon black 10 Nitrocellulose 2 Methyl ethyl ketone peroxide triol 100 Methyl isobutyl ketone 50 [Comparative example] A material consisting of the following composition 3 was applied to a polyester film with a thickness of 5.7 μm. A heat-sensitive transfer recording material of a comparative example was obtained by coating with a hot melt coater so that the thickness was 3.5 μm.

Composition 3 Candela wax 80 Parts by weight Ethylene/vinyl acetate copolymer 20 Nitrocellulose 5 Carbon black 25 Using the thermal transfer recording materials of Examples and Comparative Examples, a checkered pattern with one layer of 8 m on a side as shown in FIG. 1 was prepared. 1 to 0.61
It was transferred onto smooth paper with Bekk smoothness of 2006 using an energy of J/dot.

Dot shapes formed by each transfer 2a, 2b
When examined, it was found that in the example, the protruding portion 3a was small, as shown in FIG. 2 (A>), but in the comparative example, the dot shape 2b was small and the protruding portion 3b was large. Incidentally, when we investigated the ratio of the protruding portions 3a and 3b to the area (SR) in the case of the ideal dot shape 4 shown in FIG. However, it was confirmed that the comparative example had a large value of Ha-Δ8B/SR=1.93.

[Effect of the invention 1] As explained above, according to the heat-sensitive transfer recording material according to the present invention, the heat-melting colored transfer layer is formed as a support by two layers: the uncolored heat-melting layer containing a reactive plasticizer and the heat-melting colored transfer layer. 111 of the colored transfer layer containing sandwiched catalytic crosslinking accelerator! 311 consisting of! Because of this structure, during heating and melting, only the heat generating portion undergoes a crosslinking reaction, thereby easily reproducing dots that are very faithful to the shape of the dots of the heat generating element.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a checkered pattern, and FIG. 2 is an explanatory diagram showing the relationship between dot shapes and protruding parts. 1... Checkered pattern, 2a... Dot shape according to the example, 2b... Dot shape according to the comparative example, 3
a...Protruding part in the case of the example, 3b...
・Protruding portion in case of comparative example, 4... Ideal dot shape Applicant's agent Patent attorney Takehiko Suzue Height 1mm @ Figure 1 Obstructed dot shape 4K
4 leftover A lawn dot shape 1 (A)
(B) (C) Figure 2

Claims (1)

[Claims] It has a heat-melt colored transfer layer with a three-layer structure in which a heat-melt layer, a colored transfer layer, and a heat-melt layer are sequentially laminated on a support, and a reactive plasticizer is added to each heat-melt layer. A thermal transfer recording material characterized in that a crosslinking accelerator for the reactive plasticizer is added to the colored transfer layer.