Chromatic metallic base printed board and preparation method thereof
Technical field
The present invention relates to a kind of printed wiring board, specifically a kind of chromatic metallic base printed board and preparation method thereof.
Background technology
Printed wiring board develops into now, classifies by base material, can be divided into common line plate and metal base circuit board.In work
In industry production practices, the application to metal base circuit board, the most commonplace.But in specifically used, lead in Aero-Space etc.
In the application scenario in territory, components and parts requirements at the higher level are put forward at the aspect such as hotness, light sensation.Existing common metal base circuit board
Cannot meet device requirement in terms of temperature-sensitive, light sensitive effect.
Summary of the invention
An object of the present invention is just to provide a kind of chromatic metallic base printed board, deposits solving existing metal base circuit board
Temperature-sensitive, the poor problem of light sensitive effect.
The two of the purpose of the present invention are just to provide the manufacture method of a kind of chromatic metallic base printed board, to meet device in heat
Requirement in terms of quick, light sensitive effect.
An object of the present invention is achieved in that a kind of chromatic metallic base printed board, through anodic oxidation and surface
The surface of the metal basal board after coloring treatment is with the chemical composition coating of insulation, by the hottest on the surface of described metal basal board
Pressure viscosity connects insulating medium layer and copper foil layer constitutes metal-based copper-clad plate;Surface at the described copper foil layer of described metal-based copper-clad plate
After pad pasting, transfer line pattern and etching, taking off film, form chromatic metallic base printed board.
The surface coloring treatment of described metal basal board is to use CuSO4Carry out electrolytic coloring as electrolytic solution, or adopt
Carry out spray colouration by electrostatic spraying mode, or use organic dyestuff to carry out adsorption coloring.
Chromatic metallic base printed board of the present invention, in addition to remaining all functions of common metal base printed board, relatively common gold
Belong to substrate and add the different color in plate face.Owing to color has difference, they are different to the energy-sensitive of heat, light, meet aviation,
The use requirement in the special printing plate field such as military, simultaneously for the equipment appearance of complete machine, adds visual effect, attractive in appearance greatly
Side.
The two of the purpose of the present invention are achieved in that the manufacture method of a kind of chromatic metallic base printed board, including following
Step:
A, the metal basal board that thickness is 0.3~5mm is carried out anodic oxidation and surface coloring treatment, then by concentration
For in the concentrated sulfuric acid solution of 22g/l, 1~1.5A/dm2DC current intensity under, impregnate described metal basal board 10~
15min, after taking-up again in saturated potassium bichromate solution, at a temperature of 95~100 DEG C impregnate 5~20min, at described metal
The chemical composition coating of the Surface Creation insulation of substrate;
B, at the bonding glue-line of surface smear of described metal basal board, the most bonding insulating medium layer and copper foil layer, then through 180
~under conditions of 190 DEG C of temperature, 280~300PSI pressure, hot pressing is combined 150~160 minutes, becomes metal-based copper-clad plate;
C, by plate shearing machine, the Fructus Anisi Stellati of described metal-based copper-clad plate to be cut into production according to the jigsaw size of design required
PNL size;
D, with manual/auto laminator the surface of the copper foil layer of metal-based copper-clad plate paste last layer dry film, formed dry film
Layer, the pressure reel temperature during pad pasting is 110~120 DEG C, and pad pasting pressure is 3.5~5.0kg/cm2;At least 15 are stood after pad pasting
Minute;Then with the yellow film made in the surface para-position of described photopolymer layer, exposure, evacuation 650~750mmHg, exposure
Progression 7~9 grades;After standing at least 15 minutes again, carry out development treatment with developer solution;
E, be etched and take off after film processes again, will the line transitions that needs of design to the copper foil layer of described metal-based copper-clad plate
Surface;
F, to etching with take off the described metal-based copper-clad plate after film completes and carry out silk-screen solder mask operation in the usual way;
G, by design requirements at the plate face silk-screen character of described metal-based copper-clad plate, after toasting after silk-screen colour
Metal base printed board;Baking condition is: 140~150 DEG C, 60~70 minutes.
In step a, the anodized process to described metal basal board is:
1. deoil ungrease treatment: carry out wiping with absorbent cotton adhesional wetting solvent, after removing greasy dirt, then the cotton wiping with cleaning
Several times;Described solvent can be selected for trichloro ethylene, ethyl acetate, acetone or butanone;
2. alkali cleaning processes: cleans 15~25s with the sodium hydroxide solution of 3mol/L, then washes twice;
3. pickling processes: clean 1 minute with the salpeter solution of 2mol/L, then wash twice;
4. oxidation processes: with the concentrated sulphuric acid of 22g/L, 1~1.5A/dm2Direct current intensity under impregnate 10~15min, then
In saturated potassium bichromate solution, at 95~100 DEG C, impregnate 5~20min, then wash twice;
5. can be in the protection of Surface Creation layer of transparent, uniformity and the porous of described metal basal board after drying
Film, in order to the follow-up coloring to described metal basal board.
The surface coloring treatment of metal basal board of the present invention can have various ways.
Mode one: in step a, the surface colouring process to described metal basal board can use CuSO4As electrolytic solution
Carry out electrolytic coloring, will the good described metal basal board of anodic oxidation as negative electrode, at CuSO4The effect of electrolytic solution
Under, at the aubergine copper film of the electrolytically generated dense uniform in the surface of described metal basal board, under light irradiates, show as coppery.
Mode two: in step a, the surface colouring process to described metal basal board can use electrostatic spraying mode to carry out
Spray colouration, detailed process is:
1. defat: by described metal basal board at the H that mass concentration is 100~150g/L2SO2Middle immersion 3~5 minutes, enter
Row ungrease treatment;
2. alkali cleaning: the described metal basal board after defat is soaked in the sodium hydroxide solution that mass concentration is 45~85g/L
Steep 5~15 minutes, carry out alkali cleaning process;
3. light is gone out: the described metal basal board after alkali cleaning is immersed in the H that concentration is 200~250g/L2SO2It is 3 with concentration
~5 H of g/L2NO3Mixed solution in 3~5min, to neutralize the alkalinous metal salt of metallic substrate surfaces and to clean described gold
Belong to the surface of substrate;
4. anodic oxidation: the described metal basal board after surface is processed in the concentrated sulphuric acid that concentration is 22g/L, 1~
1.5A/dm2Direct current intensity under impregnate 10~15min, then in saturated potassium bichromate solution, at 95~100 DEG C impregnate 5~
20min, then washes twice, thus forms one layer of porous anodized film on the surface of described metal basal board;
5. half sealing of hole: the described metal basal board after anodized is immersed in hole sealing solution, described hole sealing solution
For NiF2•4H2O solution, wherein nickel ion content 0.8~1.5g/L, content of fluoride ion 0.4~0.6g/L, pH value: 6 ± 0.5, envelope
Hole speed 1um/min, sealing of hole time 1~3 minutes;
6. electrostatic spraying: carry out electrostatic spraying on the surface of the described metal basal board after sealing pores, at described metal
Forming uniform film on substrate, the film thickness of spraying is 15~30 μm;
7. drying and packaging: in drying room, the described metal basal board after electrostatic spraying is dried 2 minutes at constant temperature 180 DEG C,
It is cooled to 40~50 DEG C after taking-up, then detects, pack.
Mode three: in step a, the surface colouring process to described metal basal board can use organic dyestuff to adsorb
Coloring, detailed process is:
1. deoil ungrease treatment: carry out wiping with absorbent cotton adhesional wetting solvent, after removing greasy dirt, then the cotton wiping with cleaning
Several times;Described solvent can be selected for trichloro ethylene, ethyl acetate, acetone or butanone;
2. alkali cleaning processes: cleans 15~25s with the sodium hydroxide solution of 3mol/L, then washes twice;
3. pickling processes: clean 1 minute with the salpeter solution of 2mol/L, then wash twice;
4. oxidation processes: with the concentrated sulphuric acid of 200 ± 30g/L, temperature 20 ± 2 DEG C, at 1.4 ± 0.3A/dm2Direct current intensity
Lower dipping 10~20min, then in saturated potassium bichromate solution, at 95~100 DEG C, impregnate 5~20min, then wash two
Secondary;
5. can be in the protection of Surface Creation layer of transparent, uniformity and the porous of described metal basal board after drying
Film, in order to the follow-up coloring to described metal basal board;
6. the mechanism of the adsorption coloring of organic dyestuff: the normal pH value of organic dyestuff of shades of colour: 4~5.5, temperature 60
DEG C, immerse the time 5~15min, the anion of dyestuff enter into described metal basal board oxidation fenestra (aperture typically 120 ×
10-16M), in, adsorbed on aluminium cations by adsorption;
7. sealing of hole after coloring: use deionized water or distilled water, carries out sealing of hole, at least by boiling water to the aluminium base of coloring
20 minutes.
In the hot pressing of step b, for the described copper foil layer of 35 μ m-thick, the THICKNESS CONTROL of bonding glue-line 120 ±
10μm。
Development conditions in step d is: the concentration of sodium carbonate is 1.0%, and temperature is 30 ± 2 DEG C, the pressure 1.0 of development~
1.5kg/cm2。
In step e, the specific gravity control of etching solution 1.26~1.32, content of copper ion 110~170g/L, acid equivalent
1.0~2.0N, etch temperature 50 DEG C, speed controlling 1.5m/min;In taking off film section, NaOH concentration 2~3%, temperature 50~60
DEG C, developing powder 1.8~2.2m/min.
Chromatic metallic base printed board manufacture method of the present invention solves metal basal board at anodic oxidation and electrolytic coloring
Process difficulties during reason;By the concentration of electrolytic solution is controlled and electric current density, the control of electrolysis time, well
Solve that film layer is not colored, do not paint in local, of light color and have white point after easily taking off, colour, colour and grow dim or the problem such as dimness.
Owing to the object of different colours is different to the absorbability of light, such as red object reflection HONGGUANG, the light of other wave band is all
Can be absorbed, white object reflects whole light, and black object absorbs whole light.So, when Metal Substrate face is caught
After different colours, just can reach the effect of different reflections and absorbing light energy.It was verified that black heat absorption capacity is the strongest, red
Color takes second place, and white is the most weak.It is radiated at the metallic substrate surface of different colours by light, produces the type such as absorbing light, reflection light,
And along with Metal Substrate Surface absorption light energy number and the variations in temperature that produces is different, recycling photoelectric sensor principle is by light
A kind of bang-bang control assembly of conduct after a kind of signal of telecommunication can be changed into.
Accompanying drawing explanation
Fig. 1 is the structural representation of chromatic metallic base printed board of the present invention.
Detailed description of the invention
Embodiment 1
As it is shown in figure 1, the thickness of metal basal board 1 is 0.3~5mm, first metal basal board 1 is carried out anodized and table
Face colouring processes, the chemical composition coating 2 that the Surface Creation at metal basal board 1 insulate, viscous on the surface of metal basal board 1 successively hot pressing
After connecing insulating medium layer 3 and copper foil layer 4, i.e. constitute metal-based copper-clad plate.Metal-based copper-clad plate copper foil layer 4 surface through patch
Film, transfer line pattern and etching, take off the operation such as film after, i.e. form chromatic metallic base printed board of the present invention.
The surface coloring treatment of metal basal board 1 can use CuSO4Carry out electrolytic coloring as electrolytic solution, or use
Electrostatic spraying mode carries out spray colouration, or uses organic dyestuff to carry out adsorption coloring.
Embodiment 2
The manufacture method of chromatic metallic base printed board of the present invention comprises the following steps:
1, the metal basal board that thickness is 0.3~5mm is carried out anodic oxidation and surface coloring treatment, then by concentration
For in the concentrated sulfuric acid solution of 22g/l, 1~1.5A/dm2DC current intensity under, impregnate described metal basal board 10~
15min, after taking-up again in saturated potassium bichromate solution, at a temperature of 95~100 DEG C impregnate 5~20min, at described metal
The chemical composition coating of the Surface Creation insulation of substrate.Anodic oxidation and surface coloring treatment to metal basal board, mainly passes through
The surface of metal basal board is carried out chemistry and electrochemical treatments, is allowed to that there is certain roughness, and on its surface without becoming certain
The chemical composition coating of the high-insulativity of thickness, makes this resin film layer have high resistance, the performance such as breakdown voltage resistant.
First, to the anodized process of metal basal board it is:
1. deoil ungrease treatment: carry out wiping with absorbent cotton adhesional wetting solvent, after removing greasy dirt, then the cotton wiping with cleaning
Several times;Described solvent can be selected for trichloro ethylene, ethyl acetate, acetone or butanone;
2. alkali cleaning processes: cleans 15~25s with the sodium hydroxide solution of 3mol/L, then washes twice;
3. pickling processes: clean 1 minute with the salpeter solution of 2mol/L, then wash twice;
4. oxidation processes: with the concentrated sulphuric acid of 22g/L, 1~1.5A/dm2Direct current intensity under impregnate 10~15min, then
In saturated potassium bichromate solution, at 95~100 DEG C, impregnate 5~20min, then wash twice;
5. can be in the protection of Surface Creation layer of transparent, uniformity and the porous of described metal basal board after drying
Film, in order to the follow-up coloring to described metal basal board.
Secondly, to the surface colouring process of described metal basal board it is: use CuSO4It is electrolysed as electrolytic solution
Coloring, will the good metal basal board of anodic oxidation as negative electrode, at CuSO4Under the effect of electrolytic solution, at metal basal board
The aubergine copper film of the electrolytically generated dense uniform in surface, under light irradiates, show as coppery.
It is to be initially formed sulphuric acid oxidation coating to the principle of the electrolytic coloring of metal basal board, then enters in coloring solution
Row electrolytic coloring (result bottom oxidation fenestra of the metal particle deposition in inorganic salt), the tone of electrolytic coloring depends on gold
Belong to the distinctive color of salt itself.
As a example by aluminium base, after aluminum carries out anodized in sulfuric acid solution, product surface generates one layer
Artificial oxidation's film, the surface of this layer of oxide-film is porous, claims porous layer.And the bottom of oxide-film contacts with aluminum substrate,
It is then fine and close oxide-film thin layer, also referred to as active layer or barrier layer.This aluminium with anode oxide film soak people certain
In the electrolysis of slaine, and as an electrode (negative electrode), and another extremely can be with simple metal plate or corrosion resistant plate etc. as sun
Level.When the two poles of the earth pass to alternating current simultaneously (typically under conditions of low-voltage and low current density), aluminum products the most automatically become
Becoming negative electrode, and face discharges hydrogen from it, the metal ion in metallic solution is formed about strong at aluminum products simultaneously
Ion concentration is poor, and is deep on active layer by porous layer, alternately bears violent reduction and aoxidizes slowly
Effect.Namely active layer attracts metal ion consumingly, and happen over and over again electric discharge with the negative electrostatic charge produced there and separate out
Metal or metal-oxide, and be deposited at the bottom 3~6um of oxide-film minute aperture, metal particle amount of precipitation is about 0.01g/
dm2.These microgranules generally in hair-like, spherical or granular, its a diameter of 10~15nm, a length of a few micrometers.In effect of light
These metal particle generation diffraction lower, just make oxide-film present shades of colour.
Using the good aluminium flake of anodic oxidation as negative electrode, lead net is anode, CuSO4It is electrolysed as electrolytic solution.
Major parameter is: CuSO4The concentration of electrolytic solution is: 20~25%;Electric current density: 10~20mA/cm2, during electrolysis
Between: 5~10min.
Anode: H2O-2e-→1/2 O2+2H+
Negative electrode: Cu2++2e-→Cu
The aluminium flake that anodic oxidation is good is attached to its surface as negative electrode, the Cu generating dense uniform during electrolysis, forms purple
Red copper film, thus show as coppery under the irradiation of light.
The surface of electrolytic coloring has the hardness identical with sulphuric acid oxidation coating and anti-wear performance, and film layer has especially
Good UV resistant irradiation performance, heat resistance is good, and has good corrosion resistance etc..
Electrolytic coloring principle: be initially formed sulphuric acid oxidation coating, then carries out electrolytic coloring (inorganic salt in coloring solution
In metal particle deposition oxidation fenestra bottom result), the tone of electrolytic coloring depends on the distinctive face of slaine itself
Color, sees table 1.
Table 1: the different tones that aluminium produces after electrolytic coloring after oxygen extremely sunization in different metal electrolytic solution.
2, hot-forming: the bonding glue-line of surface smear at metal basal board, the most bonding insulating medium layer and copper foil layer, then
Under conditions of 180~190 DEG C of temperature, 280~300PSI pressure, hot pressing is combined 150~160 minutes, becomes Metal Substrate and covers copper
Plate;In hot pressing, for the described copper foil layer of 35 μ m-thick, the THICKNESS CONTROL of bonding glue-line is preferable in 120 ± 10 μm.Glue-line is too
Bao Shi, infiltration aluminium sheet that adhesive can not be good and roughening of copper foil face, can cause punch through voltage and decline.And glue-line is blocked up, because of flowing
Property excessive and cause Copper Foil see rough and uneven in surface.It addition, for Copper Foil and aluminium sheet, its roughness is relatively big, is easily infiltrated, institute
Thick with glue-line not BITAI.For ensureing product quality and the operability of experiment, bondline thickness controls to be advisable in 120 ± 10 μm, gold
Belong to base copper-clad plate to be typically to be composited through High Temperature High Pressure with the metal basal board of 0.3~5 mm, insulating medium layer, Copper Foil.
Following process parameter to be controlled well during hot-forming:
1. according to the suitable contact pressure of different choice and the first pressing of resin system and dielectric;2. forming temperature 180
℃;3. briquetting pressure 300PSI: 4. molding time 150 minutes.
3, by plate shearing machine, the Fructus Anisi Stellati of metal-based copper-clad plate is cut into the PNL needed for production according to the jigsaw size of design
Size.
4, paste last layer dry film with manual/auto laminator on the surface of the copper foil layer of metal-based copper-clad plate, form dry film
Layer, the pressure reel temperature during pad pasting is 110~120 DEG C, and pad pasting pressure is 3.5~5.0kg/cm2.At least 15 are stood after pad pasting
Minute, then with the yellow film made in the surface para-position of described photopolymer layer, exposure, evacuation 650~750mmHg, exposure
Progression 7~9 grades;After standing at least 15 minutes again, carry out development treatment with developer solution.Development conditions is: the concentration of sodium carbonate
Being 1.0%, temperature is 30 ± 2 DEG C, the pressure 1.0~1.5kg/cm of development2。
5, after being etched again and take off film process, the line transitions copper foil layer to described metal-based copper-clad plate of needs will be designed
Surface.The acid CuCl in copper face region that will expose after fixing2Solution dissolves, and this process is etching.The proportion of etching solution
Control 1.26~1.32, content of copper ion 110~170g/L, acid equivalent 1.0~2.0N, etch temperature 50 DEG C, speed controlling
1.5m/min.By highly basic (generally NaOH) solution with exposed the wet film of light, dry film effect, the film on figure is taken off, surplus
Under have circuit and the copper face of figure, this process is taking off film.In taking off film section, the concentration of NaOH is 2~3%, and temperature is 50~60
DEG C, developing powder is 1.8~2.2m/min.
6, silk-screen solder mask operation is carried out in the usual way to etching and taking off the described metal-based copper-clad plate after film completes.
Silk-screen solder mask generally white or black.First pass through automatic screen printer imposite printing last layer solder mask;Stand 15
More than minute;Prebake conditions 72~75 DEG C again, 40~45 minutes, allow ink solidification;Then with the yellow film aligning made, exposure
Light, evacuation 650~750mmHg, exposure progression 11~13 grades;It is statically placed in more than 15 minutes the most again;By para-position, exposure OK plate
Development, the concentration of developer solution sodium carbonate is 1.0%, and temperature is 30 ± 2 DEG C, the pressure 1.0~2.5kg/cm of development2, the speed of development
Degree 2.5~3.5m/min.
7, by design requirements at the plate face silk-screen character of described metal-based copper-clad plate, after toasting after silk-screen colour
Metal base printed board.Baking condition is: 140~150 DEG C, 60~70 minutes.
8, external form processing, it is necessary first to hole, drilling pipe position, then computer boring, gong profile, V-CUT.Common metal baseline road
Plate need to use special bit, gong cutter and V-CUT cutter, it is simple to reduces the burr during boring and sharp processing and burr.Behaviour
Fold for general one piece one when making, and parameter arranges the most a lot relative to common FR-4 plate.
9, circuit, anti-welding, word, surface process etc. are with reference to requiring normal inspection;Pay special attention to overall dimensions and aperture inspection
Survey;Aperture and profile be not by by burr, burr;Do not press by any foreign impurity in plate face between circuit, hit during anti-Hi-pot test
Wear.
Embodiment 3
The manufacture method of the chromatic metallic base printed board of the present embodiment, substantially with embodiment 2, is the table to metal basal board
Face colouring processing procedure is to use electrostatic spraying mode to carry out spray colouration, and detailed process is:
1. defat: by described metal basal board at the H that mass concentration is 100~150g/L2SO2Middle immersion 3~5 minutes, enter
Row ungrease treatment.
2. alkali cleaning: the described metal basal board after defat is soaked in the sodium hydroxide solution that mass concentration is 45~85g/L
Steep 5~15 minutes, carry out alkali cleaning process.
3. light is gone out: the described metal basal board after alkali cleaning is immersed in the H that concentration is 200~250g/L2SO2It is 3 with concentration
~5 H of g/L2NO3Mixed solution in 3~5min, to neutralize the alkalinous metal salt of metallic substrate surfaces and to clean described gold
Belong to the surface of substrate.
4. anodic oxidation: the described metal basal board after surface is processed in the concentrated sulphuric acid that concentration is 22g/L, 1~
1.5A/dm2Direct current intensity under impregnate 10~15min, then in saturated potassium bichromate solution, at 95~100 DEG C impregnate 5~
20min, then washes twice, thus forms one layer of porous anodized film on the surface of described metal basal board;Anodic oxidation
Purpose be exactly mainly to form one layer of porous anodized film on the surface of aluminum base, for the sealing of hole of rear operation and electrostatic japanning
Material lays the first stone.
5. half sealing of hole: technological requirement is normal-temperature hole sealing (being also called cold seal hole), will be through the metal after anodized
Substrate immerses in hole sealing solution, and described hole sealing solution is NiF2•4H2O solution, wherein nickel ion content 0.8~1.5g/L, fluorine from
Sub-content 0.4~0.6g/L, pH value: 6 ± 0.5, sealing of hole speed 1um/min, sealing of hole time 1~3 minutes.
Sealing of hole principle is: in the micropore of the anode oxide film that nickel ion is deposited on metal basal board at normal temperatures.But to anode
Oxide-film can not all be closed, it is necessary to remains approximately half of fenestra, in order to the paint vehicle of adsorption electrostatic spraying.The control of half sealing of hole
System, is in the case of the concentration of hole sealing solution and deposition velocity are metastable, is mainly controlled by the time of deposition, one
As sealing of hole sedimentation time less than the degree of half sealing of hole within 3 minutes, can be ensured.
6. electrostatic spraying: carry out electrostatic spraying, on metallic substrates shape on the surface of the metal basal board after sealing pores
Uniformly film, the film thickness of spraying is 15~30um.Specifically metal basal board is put into the spray room automatically sprayed
In, the electrostatic generator in spraying equipment produces the adjustable DC high pressure of 20~90KV, exports electric current 10~20uA;Spraying equipment
Defeated paint amount control at 200ml/min, the resistivity of paint amount is typically at 45M Ω CM.During work, spray gun (i.e. nebulizer) connects negative
Pole, metal basal board connects positive pole ground connection, under the action of high voltage of high voltage power supply, with regard to shape between end and the metal basal board of spray gun
Becoming an electrostatic field, coating sprays after nozzle atomization, and the paint particles being atomized is by the spray dish of spray gun muzzle and spray cup
Edge time charged because of contact, when through gas ionization zone produced by corona discharge, its surface electricity will be increased again
Lotus density.These electronegative paint particles under electrostatic field, the apparent motion of the metal basal board of guide polarity, and quilt
It is deposited on the surface of metal basal board, forms uniform film.
7. drying and packaging: in drying room, the described metal basal board after electrostatic spraying is dried 2 minutes at constant temperature 180 DEG C,
With cold front heavy rain to 40~50 DEG C after taking-up, the quality of artificial range estimation detection product, certified products are packed, during blanking packaging
Must handle with care, be strictly on guard against and damage.
Embodiment 4
The manufacture method of the chromatic metallic base printed board of the present embodiment, substantially with embodiment 2, is the table to metal basal board
Face colouring processing procedure is to use organic dyestuff to carry out adsorption coloring, and detailed process is:
1. deoil ungrease treatment: carry out wiping with absorbent cotton adhesional wetting solvent, after removing greasy dirt, then the cotton wiping with cleaning
Several times.Described solvent can be selected for trichloro ethylene, ethyl acetate, acetone or butanone.
2. alkali cleaning processes: cleans 15~25s with the sodium hydroxide solution of 3mol/L, then washes twice.
3. pickling processes: clean 1 minute with the salpeter solution of 2mol/L, then wash twice.
4. oxidation processes: with the concentrated sulphuric acid of 200 ± 30g/L, temperature 20 ± 2 DEG C, at 1.4 ± 0.3A/dm2Direct current intensity
Lower dipping 10~20min, then in saturated potassium bichromate solution, at 95~100 DEG C, impregnate 5~20min, then wash two
Secondary.
8. after drying can at the protecting film of Surface Creation layer of transparent, uniformity and the porous of metal basal board, with
It is easy to the follow-up coloring to metal basal board.
9. the mechanism of the adsorption coloring of organic dyestuff: the normal pH value of the organic dyestuff of shades of colour is 4~5.5, temperature
60 DEG C, immersing the time 5~15min, the anion of dyestuff enters into the oxidation fenestra of metal basal board, and (aperture is typically 120 × 10-16M), in, adsorbed on metal cation by adsorption.
Sealing of hole after coloring: use deionized water or distilled water, carries out sealing of hole, at least by boiling water to the metal basal board of coloring
20 minutes.