KR101039374B1 - Heat resistanst coatings and manufacturing method of it - Google Patents

Abstract

The present invention is a heat-resistant coating agent for bar code printing films having excellent heat resistance and slip printability to be applied to a PET film used as a base material in the manufacture of a bar code print film to suppress sticking and head chipping phenomenon and a method of manufacturing the same. It is about.

The heat-resistant coating agent for bar code printing films of the present invention is characterized in that the number of Si-O chains of polydiaminosiloxane intermediate obtained by anionic polymerization of polydiaminosiloxane and cyclic siloxane is 32 to 248.

Heat-resistant coating agent for bar code printing film, polydiaminosiloxane, cyclic siloxane, acrylic, thermal transfer printer, ink ribbon

Description

Heat-resistant coating agent for barcode printing film and its manufacturing method {Heat resistanst coatings and manufacturing method of it}

The present invention relates to a heat-resistant coating agent for bar code printing films having excellent heat resistance, slip properties, and printability to be applied to a PET film used as a substrate in manufacturing a bar code printing film to suppress sticking and chipping phenomena, and a manufacturing method thereof. will be.

The barcode printing film used in the barcode printer is made of a molten thermal transfer sheet having a thin PET film as a base sheet and a dye layer composed of a melt type dye and a binder on the surface of the base sheet, and a pigment and wax instead of the dye layer. BACKGROUND OF THE INVENTION A thermal melting type thermal transfer sheet provided with an ink layer is known.

In this thermal transfer sheet, the back surface is heated by the thermal head of the print to transfer the dye or ink layer of the dye layer to the transfer target and form an image. When the thermal transfer sheet is imaged by the thermal head, when a thermoplastic film such as a polyester film is used as the base film, the base film is partially deformed by the heat of the thermal head, and contaminants adhere to the thermal head or the substrate film. Sticking phenomenon occurs that wrinkles are generated.

The sticking phenomenon causes a poor conveyance of the barcode printing film, making it difficult to form an image. As a method of solving this sticking problem, heat-resistant coating materials capable of forming a heat-resistant layer for protecting a base film are currently proposed.

Conventionally, polymer coating materials containing acrylic acid esters or methacrylic acid esters of higher alcohols, and coating materials obtained by crosslinking and curing a thermoplastic resin containing hydroxyl groups with polyisocyanate (JP-A-5-39796, H6-6-33006). ). However, the above method has a problem in that it is difficult to obtain the lubricity necessary for printing a barcode for a long time in printing, and a long time aging treatment process is required for crosslinking.

In order to solve this problem, a method using a polydimethylsiloxane graft or block copolymerization has emerged. Typically, a coating material containing a polydimethylsiloxane graft copolymer and a polydimethylsiloxane copolymer coating material are used. There is an example in which heat resistance and lubricity are improved than before (Japanese Patent Laid-Open Nos. 2-274596 and 10-297123).

Recently, polydimethylsiloxane-based graft polymerization using polydimethylsiloxane graft polymers or polyolefin siloxane-containing polydimethylsiloxanes is used as a coating material. In order to reinforce the strength, a method of using a material having an alkyl group having 12 or more carbon atoms is also disclosed (Patent No. 2006-126504).

An object of the present invention is to provide excellent heat resistance, abrasion resistance, scratch resistance, lubricity, and surface migration property to PET film used as a substrate of barcode printing film, and thus a low heat-resistant protective layer having low occurrence of sticking and head chipping by thermal head. It is to provide a heat-resistant coating for barcode printing film and a method for manufacturing the same that can form a.

The heat-resistant coating agent for barcode printing films of this invention is characterized by the number of Si-O chains of polydiaminosiloxane intermediate which carried out anionic polymerization of polydiaminosiloxane and cyclic siloxane from 32-248.

In addition, the method of manufacturing a heat-resistant coating agent for a barcode printing film of the present invention, preparing a polydiaminosiloxane intermediate of anionic polymerization of polydiaminosiloxane and cyclic siloxane; Preparing a silicone-epoxy-acrylic intermediate by inducing an acrylic epoxy functional group at one end of glycidyl methacrylate at both ends of the polydiaminosiloxane intermediate; Methyl methacrylate (MMA), methacrylic acid (MAA) cross-linking agent 2-hydroethylmethacrylate (2-HEMA) free radical copolymerization to the silicon-epoxy-acrylic intermediate comprises the step of connecting the acrylic chain to prepare a coating agent.

The heat-resistant coating agent for bar code printing film prepared by the present invention has increased the number of Si-O bonds (32-248) per siloxane unit chain, thereby improving heat resistance than conventional silicone resins, amino groups at both ends Since the acrylic functional group can be introduced through the epoxy reaction. When the acrylic functional group is introduced, it is possible to polymerize the acrylic monomer through free radical reaction and synthesize a silicone-acrylic copolymer having both silicone and acrylic properties.

In addition, polydiaminosiloxanes having amino substituents at both ends have characteristics such as high thermal stability, oxidative stability, weather resistance, and dynamic flexibility, and the acrylic resin grafted thereto has high weatherability, excellent surface transition, toughness, and the like. Has advantages

In addition, when random copolymerization is used, high workability is exhibited. In the case of graft polymerization, a step of introducing a substituent capable of substituting acryl at one end is required. In general block copolymerization, a reaction is induced. Because it is very hard. However, in the case of random copolymerization, in the main chain of the silicone-epoxy-acrylic copolymer, the acryl chain occupies much more than the silicone occupied chain. Therefore, in the case of random copolymerization, since silicone chains and acrylic chains are not regularly arranged, there is a disadvantage in that the physical properties of silicon are hardly expressed. Therefore, in this product, while increasing the Si-O chain of silicon to 32 ~ 248 to compensate for the disadvantage that the physical properties of the silicon is lowered.

Hereinafter, the heat-resistant coating agent for barcode printing film of the present invention and a manufacturing method thereof will be described in detail.

The heat-resistant coating agent for barcode printing films according to the present invention is a coating agent containing polydiamino siloxane and is used by anionic polymerization of cyclic siloxane. In the anionic polymerization of polydiaminosiloxane and cyclic siloxane, the Si-O chain is pulverized through KOH and then polydiaminosiloxane and cyclic siloxane are polymerized.

Cyclic siloxane is preferably 3 to 5 Si-O chain so that ring opening can be stably caused by an anionic polymerization initiator. In particular, when the polydiaminosiloxane intermediate is maintained at 32 to 248 Si-O chains, the physical properties of silicon can be expressed constantly. As a reaction mechanism, the Si-O chain is pulverized and undergoes recombination, and the cyclic siloxane is only involved in the size of the molecular weight along the length of the chain of the product.

For example, A is polydiamino siloxane, A 'is Si-O pulverization, siloxane having hydroxyl or amine groups at one end, B is cyclic siloxane, and B' is cyclic siloxane which is linear due to Si-O pulverization. In this case, A → A 'is decomposed into A', B → B 'is decomposed, and A'-B'-A', A'-B'-B'-A 'and A'- The molecular weight increases while having the form of B'-B'-B'-A 'and A'-B'-B'-B'-B'-A' .... At this time, the cyclic siloxane not only reacts with the polydiamino siloxane by the blending ratio, but also continuously reacts according to the charged amount.

On the other hand, the method for producing a heat-resistant coating agent for bar code printing film is an anionic polymerization of polydiaminosiloxane and cyclic siloxane to produce a polydiaminosiloxane intermediate, and introducing an acrylic group into the sock end of the polydiaminosiloxane intermediate, silicon-epoxy -Preparing an acrylic intermediate, and connecting the acrylic chain to the silicone-epoxy-acrylic intermediate to prepare a coating agent.

The step of preparing the polydiaminosiloxane intermediate is produced by anionic polymerization of cyclic siloxane with polydiaminosiloxane having amino groups at both ends. In the anionic polymerization of the polydiaminosiloxane and the cyclic siloxane, the content ratio of the polydiaminosiloxane is preferably 13 parts by weight to 20 parts by weight based on 100 parts by weight of the cyclic siloxane.

In the anionic polymerization of the polydiaminosiloxane and the cyclic siloxane, the Si-O chain is pulverized through KOH, and then the polydiaminosiloxane and the welcome siloxane are polymerized. The cyclic siloxane is preferably 3 to 5 Si-O chain so that ring opening can be stably caused by KOH. In particular, when the polydiaminosiloxane intermediate is maintained at 32 to 248 Si-O chains, the physical properties of silicon can be expressed constantly. As a reaction mechanism, the Si-O chain is pulverized and undergoes recombination, and the cyclic siloxane is only involved in the size of the molecular weight along the length of the chain of the product.

The raw material usage ratio of the polydiaminosiloxane intermediate manufacturing step is used as 13 to 20 parts by weight of polydiaminosiloxane and 0.001 to 1 part by weight of KOH based on 100 parts by weight of the cyclic siloxane. At this time, if the content of the polydiaminosiloxane is too small, the length of the chain is greatly increased, and the difficulty of use is followed. If the content is too high, the length of the chain is short and the physical properties of the siloxane cannot be properly expressed. In addition, too small KOH does not cause an initiation reaction to increase the unreacted reaction. Too much KOH causes the initiation to occur in various aspects, thereby increasing the reaction time in connecting the chains of the polydiaminosiloxane, and also increasing the production of unreacted materials.

On the other hand, the step of preparing a silicon-epoxy-acrylic intermediate is produced by the epoxide reaction of an acrylate monomer having an epoxy group at both ends of the polydiaminosiloxane intermediate. At this time, the raw material use ratio for the production of the silicon-epoxy-acrylic intermediate, 50 to 250 parts by weight of methyl ethyl ketone, 50 to 250 parts by weight of toluene, glycidyl methacrylate based on 100 parts by weight of polydiaminosiloxane intermediate It is preferable that it is 1-30 weight part and 1-30 weight part of 2-hydroxyethyl methacrylates. The reaction content ratio is calculated based on the equivalence ratio, and in the case of methyl ethyl ketone and toluene can be increased or decreased by the desired solid content.

value = 1 : 1Calculation of equivalence ratio NH ₂ value:

value = 1: 1

The silicon-epoxy-acrylic intermediate is added with polydiaminosiloxane intermediate, methyl ethyl ketone, toluene, glycidyl methacrylate, and a azole catalyst and reacted with siloxane amino intermediates at 60 to 90 ° C. It is reacted with the epoxide-reacted silicone-epoxy-acrylic intermediate at the sock end.

In this reaction, glycidyl methacrylate is selected and used as an acryl-functional monomer in consideration of reaction yield, reaction conditions, manufacturing cost, and the like.

On the other hand, the step of preparing a coating agent (silicon-epoxy-acrylic copolymer), using the azo initiator, the silicon-epoxy-acrylic intermediate and methyl methacrylate (MMA), methacrylic acid (MAA), 2- as a crosslinking monomer Hydroethyl methacrylate (2-HEMA) is added and produced by free radical copolymerization reaction at 60 ~ 90 ℃. At this time, the azo initiator is azobisisobutyronitrile, the raw material ratio of the coating agent is 50 to 300 parts by weight of methyl ethyl ketone, 50 to 300 parts by weight of toluene, methyl methacryl based on 100 parts by weight of the silicon-epoxy-acrylic intermediate It is 50-300 weight part of rates, 1-30 weight part of methacrylic acid, 1-30 weight part of 2-hydroethyl methacrylates, and 0.1-5 weight part of azobisisobutyronitrile. In addition, the free radical copolymerization step is preferably random copolymerization.

In the heat-resistant heat-resistant coating agent containing the ion-polymerized polydiaminosiloxane, the weight ratio of the polydiaminosiloxane is preferably used in an amount of 10% by weight to 50% by weight. As the silicon content is increased, the heat resistance and slip resistance of the product is improved, but it is difficult to control the reaction and the characteristics of acryl are poor, and thus the film property of the heat-resistant coating agent for barcode printing film is lowered. In addition, if the silicon content is too low, it exhibits a poor heat resistance and slip resistance.

The high heat resistance suppresses sticking phenomenon and the phenomenon that the film is melted and attached to the thermal head, and the slip property improves the wear resistance of the film itself, thereby suppressing the chipping phenomenon on the thermal head.

If the content of methyl methacrylate is too small, the acrylic properties are poor, the coating film is not well formed, if too much, the physical properties of the silicone fall, the slip properties are poor, and the heat resistance is also poor. In addition, in the case of methacrylic acid has good reactivity, the acrylate helps to generate radicals in the free radical reaction, thereby affecting the reaction time shortening.

On the other hand, due to the nature of the acrylic reaction, the physical properties of the final product may be slightly lowered depending on the state of the reaction base material or the reaction method. In this case, a resin or an additive may be used to supplement the physical properties. Mainly used resins include melamine resins, PMMA resins, acetal resins, and additives include nitrocellulose and silane additives. Resin or an additive can be used 1 type or in mixture of many types.

As described above, the heat-resistant coating liquid prepared by using the polydiaminosiloxane which has been elongated while extending the chain of silicon has enhanced silicone properties, thereby improving heat resistance and slip resistance than conventional heat-resistant coating liquids.

In addition, the conventional method of controlling head chipping, which is a problem of low strength due to the inclusion of silicon, by controlling the strength of the coating solution by introducing a long-chain alkyl group, rather than using a long-chain silicon, the head chipping occurs with higher elasticity. Can be controlled.

Example 1

1) Preparation of Polydiaminosiloxane Intermediates

Into a 500 ml four-necked round bottom flask equipped with a stirrer, a thermometer, a condenser, and a nitrogen introduction tube, 200 g of cyclic dimethyl siloxane, 40 g of polydiaminosiloxane and 0.05 g of potassium hydroxide were added and polymerized at 140 ° C. for 6 hours. Thereafter, 0.05 g of acetic acid was added thereto, and the siloxane unreacted material was removed under vacuum.

2) Preparation of Silicone-Epoxy-Acrylic Intermediates

Into a 500 ml four-necked round bottom flask equipped with a stirrer, a thermometer, a condenser, and a nitrogen introduction tube, 100 g of polydiaminosiloxane intermediate, 150 g of methyl ethyl ketone, 150 g of toluene, 15 g of glycidyl methacrylate, and an appropriate amount of a tazol catalyst were added. The temperature was raised to ℃ and reacted for 2 hours.

3) Preparation of heat resistant coating agent (silicone-epoxy-acrylic copolymer)

Into a 500 ml four-necked round bottom flask equipped with a stirrer, a thermometer, and a condenser, 100 g of methyl ethyl ketone and 100 g of toluene were added and heated to 70 ° C. 50 g of silicone-epoxy-acrylic intermediate, 100 g of methyl methacrylate, 15 g of methacrylic acid, 10 g of 2-hydroxyethyl methacrylate, and 1 g of azobisisobutyronitrile were added dropwise and reacted for 2 hours. Thereafter, 0.5 g of azobisisobutyronitrile was further added to remove residual unreacted material.

Example 2

In preparing the heat-resistant protective coating of Example 1, methylmethacrylate was added to 80 g to prepare a siloxane-epoxy-acryl copolymer as a heat-resistant protective coating.

≪ Example 3 >

When preparing a heat-resistant protective coating of Example 1 to change the methyl methacrylate to 60g to prepare a siloxane-epoxy-acryl copolymer as a heat-resistant protective coating.

Example 4

In preparing the heat-resistant coating of Example 1, methylmethacrylate was added to 150 g to prepare a siloxane-epoxy-acrylic copolymer as a heat-resistant coating.

≪ Example 5 >

In preparing the heat-resistant protective coating of Example 1, only polydiaminosiloxane was changed to 15 g to prepare a polydiaminosiloxane intermediate, and then a siloxane-epoxy-acryl copolymer was prepared as a heat-resistant protective coating.

Example 6

In preparing the heat-resistant protective coating of Example 1, only polydiaminosiloxane was changed to 30 g to prepare a polydiaminosiloxane intermediate, and then a siloxane-epoxy-acryl copolymer was prepared as a heat-resistant protective coating.

Example 7

When preparing a heat-resistant protective coating of Example 1 to change only polydiaminosiloxane to 50g to prepare a polydiaminosiloxane intermediate, a siloxane-epoxy-acrylic copolymer was prepared as a heat-resistant protective coating.

Experiment and Experiment Result

The bar code printing film to which the heat-resistant protective coating solution prepared as described above is applied in a label printer (140XiIIIP manufactured by Zebra), the printing energy of which is typical, the printing speed of 4 inches / second, and the label (label width 110mm) , The length of 55mm) and the same barcode test pattern is shown in Table 1, the results of the head chipping after the printing of 20000 sheets and the sticking phenomenon of the substrate film after printing at the maximum temperature of the barcode printer.

TABLE 1

Chipping Percentage occurrence Stick King Example 1 ○ ○ ○ Example 2 ○ ○ ○ Example 3 ○ △ ○ Example 4 ○ × ○ Example 5 × ○ × Example 6 △ ○ △ Example 7 ○ △ ○ << chipping >> ○: No fusion, △: Formation of fusion, X: Generation of large amount of fusion
<< degree of occurrence >> ○: There is no percentage, △: There is percentage, ×: The percentage is accumulated
`` Stick King '' ○: no wrinkles on film, △: wrinkles on film, ×: large wrinkles on film

As shown in [Table 1], the test results of the recording medium coated with the heat-resistant protective coating according to the above embodiment vary in physical properties depending on the content change of the polydiaminosiloxane and the content change of the silicone-epoxy-acrylic intermediate. If the polydiaminosiloxane content is above a certain range, the head chipping phenomenon increases, and below a certain range, the head chipping or sticking phenomenon occurs. In addition, when the content of the silicon-epoxy-acrylic intermediate is increased, the same result as when the content of polydiaminosiloxane is changed is because the silicon-epoxy-acrylic intermediate itself is made of polydiaminosiloxane and cyclic siloxane as base. Because it becomes.

Claims (6)

A heat-resistant coating agent for bar code printing films, wherein the number of Si-O chains of the polydiaminosiloxane intermediate obtained by anionic polymerization of polydiaminosiloxane and cyclic siloxane is 32 to 248. The method according to claim 1, A heat-resistant coating agent for bar code printing films, wherein a glycidyl methacrylate is introduced at both ends of an anionic polymerized polydiaminosiloxane intermediate to produce an silicone-epoxy-acrylic intermediate by epoxide reaction. The method according to claim 2, Methyl methacrylate (MMA), methacrylic acid (MAA), and 2-hydroxyethyl methacrylate (2-HEMA) are silicone-epoxy-acrylic intermediates connected to an acrylic chain by free radical copolymerization. Heat resistant coatings for bar code printing films. Anionic polymerization of the polydiaminosiloxane and the cyclic siloxane to prepare an intermediate of the polydiaminosiloxane; Preparing an silicone-epoxy-acrylic intermediate by epoxide reacting an acrylate monomer having an epoxy group at both ends of the polydiaminosiloxane intermediate; Methyl radical acrylate (MMA), methacrylic acid (MAA), 2-hydroethyl methacrylate (2-HEMA) to the silicone-epoxy-acrylic intermediate to free radical copolymerization to connect an acrylic chain to prepare a coating agent Method for producing a heat-resistant coating for barcode printing film comprising a. The method according to claim 4, The silicone-epoxy-acrylic intermediate is 50 to 250 parts by weight of methyl ethyl ketone, 50 to 250 parts by weight of toluene, 1 to 30 parts by weight of glycidyl methacrylate, 2-hydroxy based on 100 parts by weight of the polydiaminosiloxane intermediate. 1 to 30 parts by weight of oxyethyl methacrylate, the method for producing a heat-resistant coating for bar code printing films. The method according to claim 4, The coating agent (silicone-epoxy-acryl copolymer) is 50 to 300 parts by weight of methyl ethyl ketone, 50 to 300 parts by weight of toluene, 50 to 300 parts by weight of methyl methacrylate, and meta based on 100 parts by weight of the silicone-epoxy-acrylic intermediate. 1-30 weight part of acrylic acid, 1-30 weight part of 2-hydroethyl methacrylates, and 0.1-5 weight part of azobisisobutyronitrile, The manufacturing method of the heat-resistant coating agent for barcode printing films characterized by the above-mentioned.