CN1105936A

CN1105936A - Light printing laser offset plate and its production method

Info

Publication number: CN1105936A
Application number: CN 94104931
Authority: CN
Inventors: 汪勤慰
Original assignee: JIEYIN FINE CHEMICAL TECHNOLOGY CORP BEIJING
Current assignee: JIEYIN FINE CHEMICAL TECHNOLOGY CORP BEIJING
Priority date: 1994-05-09
Filing date: 1994-05-09
Publication date: 1995-08-02

Abstract

The method for producing laser offset plate for light print includes such steps as coating cementing layer made of high-molecular binder such as polyethylene acetate emulsion on polyester substrate, and further coating hydrophilic layer made of hydrophilic macromolecular material (polyvinyl alcohol), cementing agent (poly ethylene acetate), metal and rare-earth oxide or its salts, surfactant (Tween), solvent (ethyl acetate) and dye, and features low shrink rate of plate, no need of developing and fixation, and high printing durability (more than 15000 pages).

Description

Light printing laser offset plate and its production method

The present invention relates to a kind of plate that is used for light typographic laser offset plate and preparation method thereof, particularly a kind of is the plate preparation method of substrate with the polyester with light printing laser offset plate.

Up to this point; no matter be used for the offset plate of light printing is that dry method or wet method nearly all are to adopt the paper substrate of zinc oxide; method for platemaking as the dry oxidation zinc paper substrate that CN1044542A announced; need carry out the statohm version on sheet material handles; promptly on sheet material, coat various conductive layers; the barrier layer; multiple coating such as photosensitive layer and protective layer; the coating process complexity; needed raw material is various; particularly owing to be the paper substrate that adopts zinc oxide, promptly its substrate is a paper, is out of shape so be easy to suction; shrinkage factor is big; the low shortcomings such as (promptly can only print less umber) of pressrun is developed simultaneously again; photographic fixing is handled, and the formality of not only making a plate is loaded down with trivial details; the length that expends time in the more important thing is that these treatment fluids cause environmental pollution.Though the polyester-type offset plates is adopted in Russian Patent such as SU000742859 report, also to develop, operation such as photographic fixing.

The object of the present invention is to provide a kind of with polyester sheet (the industrial polyester flake that is commonly called as) as substrate, and scribble the plate and preparation method thereof of the light printing laser offset plate of tack coat and hydrophilic layer, its advantage is that this plate is difficult for suction, dimensionally stable, the pressrun height, definition improves greatly, need not to develop, photographic fixing, coating are less, the novel light printing laser offset plate plate of the easy non-environmental-pollution again of preparation method.

Embodiment of the present invention are: (1) component aspect is the polyester sheet (industrial being commonly called as is polyester flake) of 0.07-0.175 millimeter with thickness, coat a tack coat earlier, this tack coat is one or both binding agents of forming that contain in the following component, high polymer binder or its mixture as polyvinyl acetate emulsion, vinyl acetate-ethylene copolymerization emulsions, vinylidene chloride, polyvinyl alcohol etc., the effect of binding agent is the cohesive force of reinforced polyester substrate and hydrophilic layer (below will mention), and the phenomenon that hydrophilic layer comes off takes place when preventing to print.

Coat hydrophilic layer then on this tack coat again, this hydrophilic layer is made up of following six class materials.

(I) high molecular weight hydrophilic polymer, as gelatin, Arabic gum, polyvinyl alcohol, hydroxy alkyl cellulose, one or both mixtures are formed in the organosilicon polymer;

(II) binding agent is made up of following mixtures a kind of or two kinds, as polyvinyl acetate emulsion, and vinyl acetate-ethylene copolymer emulsion, vinyl chloride-vinyl acetate copolymer emulsion, polyvinyl formal, cellulose acetate etc.;

(III) metal oxide and rare earth oxide and inorganic salts thereof are as titanium oxide, silica, zinc oxide, aluminium oxide, calcium carbonate, magnesium carbonate, magnesia, cerium oxide, lanthana etc.;

(IV) solvent: as ethyl acetate, butyl acetate, ethanol, acetone and water.

(V) surfactant and dispersant: as tween, aminomethyl phenyl organic silicone oil, Sodium Polyacrylate, calgon etc.;

(VI) dyestuff: as bromjophenol blue, methylene blue, rhodamine B etc.

The effect of high molecular weight hydrophilic polymer is because the function of its possess hydrophilic property and absorption ink powder in the hydrophilic layer, when plate-making, can be transferred to by the ink powder picture and text on Xerox or the laser printer toner cartridge on the version (substrate), after solid version, just make offset plate, picture and text total points on the offset plate has the oleophylic China ink, and blank total points possess hydrophilic property can print so the space of a whole page is directly loaded onto offset press.

What the effect of the binding agent in the hydrophilic layer was identical mainly is that the hydrophilic high mol material is firmly stuck on the polyester substrate, does not contain the generation obscission when making printing.

The effect of metal oxide in the hydrophilic layer and rare earth oxide and inorganic salts thereof is similar, plays the curing agent effect, and the cohesive force of binding agent is strengthened.

The dispersant in the hydrophilic layer and the effect of surfactant be, various materials can evenly be disperseed, and makes this offset plate quality even.

The main effect of dyestuff is:

The proportioning of six class materials following (weight fraction) in the above-mentioned hydrophilic layer:

Hydrophilic high mol class: 5-15

Binding agent: 10-30

Metal oxide and rare earth oxide and inorganic salts thereof: 30-100

Solvent: 80-120

Dispersant and surfactant: 2-10

Dyestuff: 0.001-0.01

(2) preparation method, be earlier the binding agent of tack coat or its mixture to be made solvent with ethyl acetate, being made into concentration is 5-50%, polyester substrate is soaked in this binder solution then, (generally the amount of being coated with is 10-100 gram binding agent/every square metre of substrate) after removing airing, to use Electrostatic Treatment, its voltage again be 1KV-1.5KV.Coat (immersion type) hydrophilic layer (generally the amount of being coated with is 100-400 gram hydrophilic layer material/square metre substrate) again, take out airing.

Certainly, the mode of coating also can adopt roll coating process except that soaking; Drying mode also can adopt hot air drier or infared dryer except that airing, baking temperature is controlled between 60-150 ℃.

Following preference elaborates to the present invention, but does not mean that limitation of the scope of the invention.

Example 1:

(1) preparation of tack coat material, it at a general stainless steel volume that has stirring 100 liters blender, add earlier 70 liters of aqueous solvent, stirring and adding 7 kilograms of polyvinyl acetate resins down for 45 ℃ in temperature, fully to form concentration be 10% tack coat material in dissolving.

(2) preparation of hydrophilic layer material: in 200 a liters general stainless steel blender that has stirring, add 40 kilograms of solvent ethyl acetates earlier, then add 10 kilograms of polyvinyl alcohol, 20 kilograms of vinyl acetate-ethylene copolymers, 40 kilograms of titanium oxide, 0.1 kilogram of cerium oxide, tween-18 are 6 kilograms, 0.005 kilogram of dyestuff bromjophenol blue fully mixes.

(3) be that 0.1 the polyester sheet back of weighing is soaked in taking-up in about 10 minutes in the solution of (1) with thickness under 45 ℃ of temperature, airing under air, check weighing measures to such an extent that the tack coat material of coating of every square millimeter of polyester sheet is 50 grams again, at voltage is to carry out Electrostatic Treatment under the 1KV, and then will locate in the solution that sheet is soaked in (2) about totally 10 minutes, taking-up was descended dry 1 hour in 70 ℃ of temperature in hot air drier, and the polyester sheet that records every square millimeter that weighs is again coated hydrophilic layer material 500 grams.

(4) the above-mentioned polyester sheet of coating tack coat and hydrophilic layer is carried out solid plate and printing by existing technology on general laser printer, the clarity of picture and text is than using electrofax paper to do the obviously much higher of substrate at present, and the pressrun height can reach 16,000, shrinkage factor is≤0.05%.

Example 2-example 6 only changes some batch ingredients in tack coat and the hydrophilic layer, and all the other conditions are identical with example 1, the results are shown in Table 1.

Table 1

Example	The tack coat component	The hydrophilic layer component	Be coated with back polyester sheet performance measurement
						Shrinkage factor %	Definition	Pressrun (printed sheet number)
			2	Vinyl acetate--vac emulsion	Gelatin, polyvinyl acetate, ethanol methyl organic silicone oil, methylene blue				0.04	High	16,000
3	The vinylidene chloride emulsion	Hydroxyethylcellulose, cellulose acetate, water, PAA, rhodamine B				0.04	High	15,500
			4	Polyvinyl acetate vinylidene chloride mixed liquor	CMC, polyvinyl formal, acetone, calgon, bromjophenol blue				0.03	High	16,000
5	Poly-vinyl alcohol solution	Organic silicone oil, vinyl chloride---vinyl acetate, butyl acetate, Sodium Polyacrylate, bromjophenol blue				0.005	High	15,800
			6	Acetate emulsion	I claps glue, vinyl acetate---ethylene copolymer, acetone, tween one, rhodamine B				0.04	High	16,000

The advantage of polyester adhesive forme of the present invention is as follows:

(1) picture and text definition height, pressrun height, shrinkage factor are less than 0.05%.

(2) preparation method is simple, adopts common apparatus.

(3) non-environmental-pollution.

Claims

1, a kind of sheet material that is used for light typographic laser offset plate is characterized in that:

(1) substrate is a polyester;

(2) scribble tack coat on the substrate, it is by polyvinyl acetate emulsion, vinyl acetate-ethylene copolymerization emulsions, and one or both mixtures in vinylidene chloride, the polyvinyl alcohol are formed;

(3) coat hydrophilic layer again on the tack coat of substrate, (I) high molecular weight hydrophilic polymer wherein is by gelatin, Arabic gum, and polyvinyl alcohol, hydroxy alkyl cellulose, one or both mixtures in the organosilicon polymer are formed.

(II) binding agent wherein is made up of following mixtures a kind of or two kinds, as polyvinyl acetate emulsion, and vinyl acetate-ethylene copolymer emulsion, vinyl chloride-vinyl acetate copolymer emulsion, polyvinyl formal, acetate fiber;

(III) metal oxide and rare earth oxide and inorganic salts thereof wherein, as titanium oxide, silica, zinc oxide, aluminium oxide, calcium carbonate, magnesium carbonate, magnesia, cerium oxide and lanthana;

(IV) solvent wherein: as ethyl acetate, butyl acetate, ethanol, acetone, water;

(V) surfactant and dispersant such as tween, aminomethyl phenyl organic silicone oil, Sodium Polyacrylate wherein, calgon;

(VI) dyestuff wherein is as bromjophenol blue, methylene blue, rhodamine B;

2, the preparation method of the light typographic laser offset printing sheet material of a kind of usefulness is characterized in that:

Step is as follows:

(I) is the 0.07-0.175 millimeter with the thickness of the polyester substrate of (1) in the claim 1;

(II) coats the binding agent of the tack coat of (2) in the claim 1 on polyester substrate, being made into concentration is 5-50%, and the amount of being coated with is that every square metre of substrate is a 10-100 gram binding agent, and the voltage that carries out Electrostatic Treatment behind the airing is 1KV-1.5KV;

(III) coats the hydrophilic layer material by (3) in the claim 1 again, and the amount of being coated with is every square metre of substrate 100-400 gram hydrophilic layer material, and baking temperature is 60-150 ℃.