KR100454084B1 - Cleaning and protecting composition for cleaning pre sensitized plate for offset printing - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning and protecting agent for cleaning ink applied during printing of a PS plate (hereinafter referred to as 'PS plate') used in an offset printing machine and protecting the PS plate for a short time. The present invention provides a method for preparing a cleaning and protecting agent for the plate containing a polishing powder, an aliphatic hydrocarbon having 12 to 18 carbon atoms, a hydrophilic polymer and a nonionic surfactant.

Description

Cleaning and protecting composition for cleaning pre sensitized plate for offset printing}

The present invention is to quickly remove the ink on the non-fire line in the printing PS plate used for offset printing, to further improve the quality of printing by coating the hydrophilic polymer on the non-fire line, and to dilute the cleaning and protective agent according to the invention before and after printing The present invention relates to a printing plate cleaner and a protective agent for printing, which can be applied for a short time by the hydrophilic polymer to preserve the plate.

Pre-Sensitized Plate used in the printing machine is a term used as a generic term for a printing plate in which a photosensitive material is applied to a support in advance, and generally refers to a PS plate for offset flat plate printing. PS is a type of film that radiates light. It is divided into two types, negative and positive. In the case of negative type, plate making of negative plate is made by sticking film to light and hardening the part which receives light, and the part which does not receive light is melted in photosensitive layer developer and removed. In the case of the positive type, when the film is intimately contacted with light, the photosensitive layer of the lighted part is decomposed and dissolved in the developer, and the non-lighted part is left in the line of fire. The printed PS plate is made of a drawing line having a high affinity for ink and a non-drawing line having a low affinity for ink. The ink is smoothly attached to the drawing section having high ink affinity by supplying water and ink to the plate surface. The non-flammable non-flammable portion forms a thin layer of water by using a damp solution (condensate) to suppress ink from being buried. In this way, printing is performed by using the property of water and ink (fat) repelling each other. In this way, the ink deposited on the caustic part is transferred to the blanket, and is then printed on the printed object therefrom. When printing is not performed for a long time or the water solution is not sufficiently water-retained, ink may be deposited on the non-fired portion of the plate, or a share of the paper may be attached to the plate.The ink buried therein is transferred to the blanket so that the quality of printing can be improved. Will drop. Organic solvents for removing the ink of the non-wire portion include aromatic BTI-based materials such as benzene and toluene and aliphatic hydrocarbon solvents. In addition, alcohols and ester derivatives can remove the ink. Although it is a carcinogen, it is restricted in industrial use because it is an environmental pollutant.Also, aliphatic hydrocarbons are environmentally friendly and relatively safe to humans, but they have poor ink cleaning ability, so they tend to use a long time or use a large amount of alcohol and The solvent of the ester derivative also dissolves part of the lipophilic resin in the caustic part, thereby reducing print quality.

The present invention does not use any non-X solvents, which are carcinogenic toxic solvents, by adding wax coating to fine abrasives to supplement the dissolving power of aliphatic hydrocarbons and to quickly remove foreign substances due to the share of paper. It is an object of the present invention to provide a PS plate cleaning and protective agent which can be used to selectively remove only printing ink without dissolving a lipophilic resin having high affinity for ink of the wire part.

The present invention not only quickly removes the remaining ink on the non-fire line and the wire line during printing, but also quickly removes a portion of the fine plate by foreign matter such as paper stock, so that the ink is evenly applied to the fire line during printing. In addition, by applying a hydrophilic polymer to the non-radiation portion to prevent ink from contacting the non-radiation portion, it is an object of the present invention to provide a Ps plate cleaning and protective agent that can improve the clarity of printed matter and print quality.

In addition, the present invention does not use a toxic solvent, and an object of the present invention is to provide a Ps plate cleaning and protecting agent to protect the burner portion, to quickly remove the foreign matter and printing ink of the non-burner portion and to protect the non-burner portion with a hydrophilic polymer.

The present invention is a technology for quickly removing the ink and foreign matter of the non-fired line during printing of printed Ps plate without using organic solvents of benzene and toluene, and using aliphatic hydrocarbons having 12 to 18 carbon atoms and coated abrasives as organic solvents. It has excellent cleaning power without the use of X-based organic solvents, and contains a hydrophilic polymer that protects the non-flammable portion of the PS plate and provides an environmentally friendly cleaning and protection agent for the plate. In general, the use of an abrasive may cause the polishing board to be polished thinly, which may damage the wire part of the plate itself. Therefore, the polishing agent does not directly polish the plate, and the coating agent is a material that can easily dissolve the varnish liquid of the ink. The coating increases the weak cleaning power of aliphatic hydrocarbon as an organic solvent and increases the cleaning power with environmentally friendly materials.

The abrasive used in the present invention is a petroleum resin having a carbon number of 9 using a burnet having an average particle diameter of 1.0 to 100 μm of zeolite (fluorite), fluorite, kaolin (kaolin), ceresite, diatomaceous earth, silica gel, talc and mica. Natural wax and resin are coated to form a coating polishing agent that is compatible with lipophilic materials, and is made by emulsifying aliphatic hydrocarbons and hydrophilic polymer aqueous solutions as surfactants as organic solvents. As a coating method of the coating polishing agent used in the present invention, rosin-based resins and petroleum-based resins are dissolved in ethyl ether or an organic solvent which can be easily dissolved at room temperature, and then, diatomaceous earth or other abrasive is added and stirred for 1 to 2 hours. Can be removed to create a coated abrasive. In another method, a paraffin wax, a rosin-based resin, silica gel is added, a solvent such as ethyl acetate is added, the temperature is raised to 70 to 80 ° C., stirring is carried out for 30 minutes, and the solvent is removed under reduced pressure to form a coating polishing agent. In the above case, a method of manufacturing the coating abrasive itself is used, and when preparing the cleaning agent, a solvent containing the coating polishing agent can be made by using the aliphatic hydrocarbon directly used as the organic solvent as the raw material for making the cleaning agent. Natural or petroleum-based waxes and resins are added to aliphatic hydrocarbons and heated to a suitable temperature where the resins can be placed. Since resins and waxes have many solubilities that are insoluble in common aliphatic hydrocarbons, the resins and waxes are crystallized or solidified while gradually lowering the temperature to coat the abrasive. The aqueous solution containing the organic solvent layer and the water-soluble polymer thus prepared can be emulsified using a surfactant to complete the product.

The surfactant in the present invention is a polyionic ethylene alkylphenyl ether, polypropylene glycol alkyl phenyl ether, polyoxyethylene alkyl ether, polypropylene glycol alkyl ether, sorbitan fatty acid ether derivative and polyoxyethylene sorbitan fatty acid as nonionic surfactant. Ester derivatives and the like can be used.

The organic solvent in the present invention may be used each or in combination of paraffin oil, natural oil and aliphatic hydrocarbon having 12 to 18 carbon atoms.

As the hydrophilic polymer in the present invention, siemci (carboxymethyl cellulose), polyvinyl alcohol, gum arabic and the like can be used.

The PS plate cleaning and protecting agent according to the present invention may use materials such as sorbitan, propanediol, butanediol and glycerin for flexible operation in use.

PS plate cleaning and protective agent according to the present invention to prevent the contamination of the non-sensitized portion by the ink by quickly removing the ink on the non-sensitized portion during the offset printing with the composition of each or a combination of the above and applying a hydrophilic polymer to the non-sensitized portion As a cleaning and protecting agent, it is composed of an organic material which quickly removes the ink, a moist material and an aqueous hydrophilic polymer solution and a surfactant for increasing the hydrophilicity of the non-active portion. Hereinafter, preferred embodiments and comparative examples of the present invention will be described. The following examples are intended to illustrate the invention and should not be understood as limiting the scope of the invention.

Example

The plate cleaning and protecting agent according to the present invention will be described in the following examples, which are not intended to limit the present invention.

1. As a general manufacturing method, an abrasive, an organic solvent, and a wax are placed in a reaction vessel, and the temperature is maintained at 70 to 80 ° C., followed by stirring to allow the abrasive to be sufficiently coated, followed by lowering the temperature to 10 to 60 ° C., and preparing the water-soluble polymer solution. After adding and surfactant and stirring well, other additives were administered to complete the product.

2. As another manufacturing method, the abrasive, organic solvent and wax were added and maintained at 70 to 80 ° C., followed by stirring with a surfactant, followed by administration of water-soluble polymers and other additives and lowering the temperature to complete the product.

3. As another manufacturing method, the coating polishing agent, the organic solvent, the surfactant and the water-soluble polymer solution were all added, the temperature was stirred at 70 to 80 ℃ for 1 to 10 hours and then cooled to complete the product.

Example 1

20 g of petroleum resin having 9 carbon atoms was dissolved in 1000 g of ethyl ether, and 100 g of sericite (average particle size of 20 µm or less) was added thereto, stirred for 30 minutes, and then distilled off ethyl ether to make powder. .

Example 2

To prepare the coating powder solution, add aliphatic hydrocarbon 500g, ceresin wax 4g, rosin 2g and kaolin 8g, raise the temperature to 70 ℃ and stir for 1 hour, then slowly lower the temperature to room temperature and stir to complete the coating powder solution. It was.

Example 3

[0030] The PNS plate cleaning and protecting agent according to the present invention was prepared using the aliphatic hydrocarbon solvent, the coated kaolin powder, the gum arabic and the polyethylene nonylphenol as the main ingredients as shown in Table 1 below.

Example 4

Aliphatic hydrocarbons and vegetable oils were used as a method of preparing the coating powder, but the coating powder was prepared in a blending ratio as shown in Table 2 below.

TABLE 2

As described above, the PSP cleaning and protecting agent according to the present invention can be converted into an environmentally friendly working environment as a cleaning and protecting agent that replaces an aromatic organic solvent compound such as benzene or toluene. It is possible to improve the quality during printing by smoothly removing the ink attached to the slabs of non-fire line, and it is possible to protect the plate by applying it before printing because it can protect the plate for a short time

Claims (3)

3.5 to 35.5 weight% of aliphatic hydrocarbons having 12 to 18 carbon atoms, 3.1 to 32.5 weight% of the coating polishing agent, polyoxyethylene nonylphenyl ether (5EO), polyoxyethylene nonylphenyl ether (10EO), polyoxyethylene nonylphenyl ether (15EO) , 10 to 15% by weight of at least one surfactant selected from the group consisting of polyoxyethylene nonylphenyl ether (20EO), polyoxyethylene nonylphenyl ether (25EO), or a mixture of two or more thereof, gum arabic or Siem as a water-soluble polymer 2 to 15% by weight and remaining water, including the water, wherein the coating and polishing agent is made by coating an abrasive powder such as kaolin or sericite with petroleum resin or wax having 9 carbon atoms, including other hydrophilic polymers, and the like. PS plate cleaning and protective agent composition for offset printing, characterized in that consisting of. delete delete