JP2002346633A - Method for laser marking - Google Patents

Method for laser marking

Info

Publication number
JP2002346633A
JP2002346633A JP2001161146A JP2001161146A JP2002346633A JP 2002346633 A JP2002346633 A JP 2002346633A JP 2001161146 A JP2001161146 A JP 2001161146A JP 2001161146 A JP2001161146 A JP 2001161146A JP 2002346633 A JP2002346633 A JP 2002346633A
Authority
JP
Japan
Prior art keywords
surface
metal material
coating film
laser
marking
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2001161146A
Other languages
Japanese (ja)
Inventor
Else Albright Charley
Takao Hiyamizu
Ryuzo Yamada
エルス オルブライト チャーリー
孝夫 冷水
龍三 山田
Original Assignee
Daido Steel Co Ltd
大同特殊鋼株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Daido Steel Co Ltd, 大同特殊鋼株式会社 filed Critical Daido Steel Co Ltd
Priority to JP2001161146A priority Critical patent/JP2002346633A/en
Publication of JP2002346633A publication Critical patent/JP2002346633A/en
Application status is Pending legal-status Critical

Links

Abstract

(57) [Problem] To improve the visibility and durability of an identification symbol when marking the identification symbol on a metal material surface using a laser marking method. SOLUTION: The laser marking method according to the present invention includes a coating forming step of forming a coating 12 on the surface of a metal material 10, and irradiating the surface of the coating 12 with a laser along a predetermined pattern. The coating 12
And a marking step of forming a concave portion 14 on the surface of the metal material 10 at the same time. In this case, the pattern to be marked is preferably a dot pattern that displays information by a combination of dots. The depth of the recess 14 is preferably 100 μm or more and 1000 μm or less. Further, the coating film 12 includes a surface treatment agent for forming fine irregularities on the surface of the metal material 10 and a metal material 10
Paint containing a pigment having a brightness difference with the surface of the metal material 10
It is preferable to form by applying to the surface of.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser marking method, and more particularly, to a laser marking method suitable as a method for forming an identification symbol on the surface of a metal material such as a hot billet, a hot coil, a steel plate for ships, and the like. About.

[0002]

2. Description of the Related Art In the manufacturing process of metal materials such as plate materials, pipe materials, and bar materials, and metal parts such as automobile parts and marine steel plates, a serial number, a lot number, a manufacturing history, a kind, a product name, 2. Description of the Related Art Marking is performed with an identification symbol such as a manufacturing date and a company name. In particular, in a manufacturing process in which a small number of products of various types flow, such as a manufacturing process of a steel plate for a ship, marking of the identification symbol on the product is important.

As a method of marking such a metal material, for example, an embossing method of engraving the surface of the metal material using a metal type, a stamping method of transferring an imprint on the surface of the metal material using a stamp plate, a metal method There are known an ink jet method in which ink is sprayed on a material surface, and a laser marking method in which a metal material surface is irradiated with laser light to cause decomposition, melting, evaporation, carbonization, oxidation, discoloration, foaming, and the like in an irradiated portion.

[0004] Among these, the laser marking method,
Since the object can be marked in a non-contact state, the material of the object can be selected, and automation is relatively easy, so it can be particularly distinguished on the surface of high-temperature metal materials such as hot billets and hot coils. It is used as a marking method for forming symbols.

In order to directly mark an identification symbol on the surface of a metal material using a laser marking method, it is necessary to focus a laser beam on a minute spot diameter to increase the power density. Also, in order to allow the identification symbol formed on the surface of the metal material to be easily read visually or by a recognition device, it is necessary to form a concave portion having a predetermined width and depth on the surface of the metal material.

However, there is a problem that it takes a long time to form a recess having a predetermined width and depth on the surface of a metal material by using a laser marking method. Further, even if such a concave portion is formed on the surface of the metal material, there is a problem that the visibility is poor because the marking portion is similar to the color of the background. In particular, when marking is performed on the surface of a high-temperature metal material, visibility is significantly reduced due to a dark oxide film formed on the surface.

To solve this problem, various methods have been conventionally proposed. For example, JP-A-63-176
No. 184 discloses that a steel material surface is coated with a heat-resistant paint containing titanium oxide and an inorganic phosphoric acid aqueous solution to form a film, and then the steel material surface is irradiated with a laser beam, and only the portion of the film irradiated with the laser beam is irradiated. There is disclosed a method of laser marking a steel material surface for evaporating and removing the steel.

For example, JP-A-6-297166 discloses a paint spray for spraying a paint on a work surface of a metal material and a laser beam irradiation on the work surface of the metal material to which the paint is applied. A laser marking device having a laser head for removing only paint is disclosed.

[0009] For example, Japanese Patent Application Laid-Open No. 59-73190 discloses that a predetermined portion of a member to be marked is coated with a different color for each piece of marking information, and then the coated portion is irradiated with a laser beam to be marked. A marking method for marking predetermined information by engraving a thin surface of a member is disclosed.

Further, Japanese Patent Application Laid-Open No. 56-19794 discloses that a surface of a member to which a powder coating is adhered is irradiated with a laser beam so that the irradiated portion of the powder coating is fused to the surface of the member. A marking method using a laser beam is disclosed.

[0011]

A method of forming a coating film on the surface of a metal material and removing or fusing only the coating film on the portion irradiated with the laser, or a method of engraving the surface of the metal material thinly has a low power density. Even laser light can be used for marking. Therefore, the marking can be performed more efficiently than the method of marking directly on the surface of the metal material. Further, there is an advantage that the difference in luminance between the marking portion and its surroundings is increased by the coating film, and the visibility is improved.

However, the coating film formed on the surface of the metal material has poor durability and is easily peeled off by external force.
Therefore, in the conventional method, the visibility immediately after the marking is excellent, but the coating film is peeled off several months after the marking is performed, the visibility is significantly reduced, or the marking information is lost. There's a problem.

The problem to be solved by the present invention is to improve the visibility and durability of a marked identification symbol when marking the identification symbol on the surface of a metal material using a laser marking method.

[0014]

In order to solve the above-mentioned problems, a laser marking method according to the present invention comprises a coating film forming step of forming a coating film on a surface of a metal material, and a coating film forming process in which the coating film is formed along a predetermined pattern. Irradiating the surface of the laser, at the same time to remove the coating film at the portion irradiated with the laser,
A marking step of forming a concave portion on the surface of the metal material.

[0015] The laser marking method according to the present invention comprises:
After the coating film is formed on the surface of the metal material, the coating film is removed along a predetermined pattern by laser irradiation, so that an identification symbol having excellent visibility can be formed. Further, since the concave portion having a predetermined depth is formed on the surface of the metal material at the same time when the coating film is removed, the marked identification symbol does not disappear even if the coating film is peeled.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a process chart of a laser marking method according to one embodiment of the present invention. 1, the laser marking method according to the present embodiment includes a descaling step, a coating film forming step, and a marking step.

First, the descaling step will be described. As shown in FIG. 1A, when an oxide film 10a is formed on the surface of a metal material 10, the oxide film 1
If the identification code is directly marked from above 0a, the oxide film 10a may peel off after the marking, and the identification code may disappear. Therefore, in such a case, it is preferable to remove (descaling) the oxide film 10a formed on the surface of the metal material 10 before performing the marking.

Specifically, descaling is performed when the metal material 10 is a hot material heated to 200 ° C. to 1000 ° C. or a cold material having an oxide film 10a which is easily peeled. Done if done. In particular, the metal material 10
Is an iron-based material, and its temperature is 700 ° C to 100 ° C.
When the temperature is 0 ° C., a black oxide film 10 a is formed on the surface of the metal material 10, so that descaling is preferably performed. On the other hand, when marking is performed on the metal material 10 (cold material) at room temperature where no oxide film is formed on the surface, the descaling step is unnecessary.

It is not necessary to perform the descaling on the entire surface of the metal material 10, and it is sufficient to perform the descaling only on at least the portion where the identification symbol is marked. The descaling method is not particularly limited, and various methods can be used. Specifically, a method of shaving off the oxide film 10a at the marking portion using a wire brush, or as shown in FIG.
A preferable example is a method of injecting high-pressure water from 0 to peel off the oxide film 10a.

When descaling is performed using the injection nozzle 20, the pressure of the high-pressure water is such that the oxide film 10a can be efficiently removed and the metal material 10 is deformed.
It is preferable to select an optimal value within a range that does not cause damage or the like. For example, when the metal material 10 is an iron-based material heated to 200 ° C. to 1000 ° C., specifically, the pressure of the high-pressure water is preferably 30 MPa or more and 500 MPa or less.

Next, the coating film forming step will be described. The coating film forming step is a step of forming a coating film 12 on the surface of the metal material 10. The method for forming the coating film 12 is not particularly limited, and various methods can be used. As a method of forming the coating film 12, specifically, as shown in FIG.
A suitable example is an air atomizing method applied to the surface of No. 0.

Further, in order to improve the visibility and durability of the identification symbol, the coating film 12 has a good adhesion to the metal material 10 and has a brightness difference from the surface of the metal material 10. Are preferred. For that purpose, a paint containing a surface treatment agent for forming fine irregularities on the surface of the metal material and a pigment having a luminance difference from the surface of the metal material 10 are used as a paint for forming the coating film 12. Is preferred.

The surface treating agent is used to form fine irregularities on the surface by chemically reacting with the metal material 10 to increase the adhesion of the pigment. Therefore, an optimum material may be selected as the material of the surface treatment agent according to the material of the metal material 10. For example, when the metal material 10 is an iron-based material, it is desirable to use a phosphate such as first aluminum phosphate as the surface treatment agent.

The pigment is used to increase the luminance difference between the coating film 12 and the surface of the metal material 10 and to improve the visibility of the marked identification symbol. Therefore, an optimal pigment material may be selected in accordance with the material of the metal material 10, the temperature, and the like.

For example, when the metal material 10 is an iron-based material and the metal material 10 is heated to a high temperature, a black oxide film 10a is formed on the surface. Therefore, in such a case, as a pigment, S containing silica as a main component is used.
It is desirable to use an i-based pigment, a Ti-based pigment containing titanium oxide as a main component, or the like. In particular, since the Si-based pigment is white, when a paint containing the same is applied to the metal material 10, a white coating film 12 having a large difference in luminance with respect to the oxide film 10a can be formed.

Further, the thickness of the coating film 12 formed on the surface of the metal material 10 is preferably from 10 μm to 200 μm. When the thickness of the coating film 12 is less than 10 μm, the paint is thin and visibility is insufficient, which is not preferable. on the other hand,
If the thickness of the coating film 12 exceeds 200 μm, the coating film 12 is easily peeled, which is not preferable. The thickness of the coating film 12 is
More preferably, it is 50 μm or more and 100 μm or less.

The paint may contain various additives for maintaining the properties of the paint, such as a dispersant and an anti-settling agent, in addition to the surface treating agent and the pigment. The paint is
As the dispersion medium, water may be used, or an organic solvent may be used. However, when the metal material 10 is a hot material heated to 200 ° C. or higher, it is preferable to use a paint using water as a dispersion medium.

The contents of the surface treatment agent and the pigment in the paint are determined by the material and temperature of the metal material 10 to which the paint is applied, the surface treatment agent and the pigment so as to obtain predetermined adhesion, brightness and durability. The optimum content may be selected according to the pigment material and the like.

Next, the marking step will be described.
In the marking step, as shown in FIG. 1D, a coating film 1 is formed along a predetermined pattern using a laser irradiation device 40.
2 is irradiated with a laser, the coating film 12 is removed from the portion irradiated with the laser, and at the same time, the metal material 10 is removed.
Are formed on the surface of the substrate.

The identification symbols representing the information on the metal material 10 are recesses 14 formed along a predetermined pattern.
It is constituted by ... The identification symbol formed by the concave portions 14, 14,... May be any of letters, symbols, numbers, or geometric patterns, or may be a combination thereof.

The recesses 14, 14,... Formed on the surface of the metal material 10 may be continuous lines, or
It may be a dot. That is, the identification symbol may be constituted by a continuous line pattern displaying information by a combination of continuous lines, or may be constituted by a dot pattern displaying information by a combination of dots. good. In particular, an identification symbol composed of a dot pattern has an advantage that a pattern can be formed in a shorter time than an identification symbol composed of a continuous line pattern.

The depth of the recesses 14 constituting the identification symbol is preferably 100 μm or more and 1000 μm or less. If the depth of the concave portions 14, 14,... Is less than 100 μm, it is difficult to determine the identification symbol when the coating film 12 is peeled off, which is not preferable. On the other hand, the depth of the recesses 14, 14,.
If the thickness exceeds 00 μm, the marking efficiency is lowered and the marking requires a long time, which is not preferable.

The width (diameter in the case of a dot pattern) of the recesses 14, 14,... Is 500 μm or more and 1500 μm.
The following is preferred. If the width of the recesses 14, 14,... Is less than 500 μm, the visibility of the formed identification symbol is undesirably reduced. On the other hand, the width of the recesses 14, 14,.
If the thickness exceeds 0 μm, the marking efficiency is reduced and the marking requires a long time, which is not preferable.

The recesses 14, 14,...
Is formed by scanning the surface of the metal material 10 with laser light emitted from the laser irradiation device 40. In this case, the recesses 14, 14,... May be formed using a single laser irradiation device 40, or may be formed using two or more laser irradiation devices 40.
.. Are formed in the metal material 1.
The surface may be any one of the front surface, the back surface, the side surface, and the end surface, and is not particularly limited.

The laser irradiating device 40 used for marking can remove the coating film 12 at the portion irradiated with the laser, and at the same time, can form the concave portions 14 having the above-described shape on the surface of the metal material 10. What is necessary is just to be able to irradiate a laser having a power density, and the structure is not particularly limited.

The laser irradiated from the laser irradiation device 40 may be a continuous wave laser or a pulsed laser. However, in order to efficiently form the recesses 14, 14,... Having a predetermined depth, it is preferable to use a pulsed laser.

Further, the position of the metal material 10 may be detected before performing the descaling, applying the paint, or irradiating the laser. If the position of the metal material 10 is detected before the concave portions 14, 14,... Are formed, the concave portions 14, 14,.
There is an advantage that an identification symbol can be marked.

Next, the operation of the laser marking method according to the present invention will be described. Metal material 10 if necessary
After performing the descaling of the surface of, after applying a paint containing a surface treatment agent and a pigment, the surface of the metal material 10
A coating film 12 having a predetermined luminance is formed. Next, after the position of the metal material 10 is detected as necessary, the surface of the coating film 12 is irradiated with a laser along a predetermined pattern. Are formed on the surface of the metal material 10 having a predetermined depth.

The laser marking method according to the present invention comprises:
After forming the coating film 12 having a predetermined brightness on the surface of the metal material 10, a laser is irradiated along a predetermined pattern, so that a metal having a low surface brightness such as an iron-based material heated to a high temperature is used. Even when marking is performed on the material 10, an identification symbol having excellent visibility can be formed.

Further, both the coating film 12 and the surface layer of the metal material 10 are removed by laser irradiation, and the metal material 1 is removed.
.. Having a predetermined depth are formed on the surface of the coating film 0.
The marked identification symbol does not disappear.

When the recesses 14, 14,... Are dots, that is, when the identification symbol to be marked is a dot pattern for displaying information by a combination of dots, the identification symbol constituted by a continuous line pattern is used. The marking time can be reduced and the load on the laser irradiation device 40 can be reduced as compared with the case of marking.

When a paint containing a surface treating agent and a pigment is used as a coating material for forming the coating film 12, the coating material 12 has a high adhesion to the metal material 10 and has a high adhesive strength.
A coating film 12 having a difference in luminance with respect to the surface of is obtained. Therefore, an identification symbol having excellent durability and visibility can be marked on the surface of the metal material 10. Further, in the case where the metal material 10 is a hot material, if the surface of the metal material 10 is descaled before the coating film 12 is formed, it is possible to avoid the disappearance of the identification symbol caused by the falling off of the oxide film 10a. Can be.

[0043]

(Example 1) As the metal material 10, 1000
Steel material heated to ℃ (Austenitic stainless steel)
Was used to mark the identification symbol. First, the oxide film 10a on the surface of the steel material was removed using the injection nozzle 20, and then a coating material was applied to the surface of the steel material using the two-fluid nozzle 30 to form the coating film 12 having a thickness of 80 μm. As the paint, an aqueous paint containing first aluminum phosphate and a Si-based pigment was used.

Next, a laser irradiation device 4 with an output of 400 W
Using 0, the surface of the coating film 12 was irradiated with a pulsed laser to mark an identification symbol consisting of a dot pattern. In the case of this example, the diameter of the dot formed on the surface of the metal material 10 was about 600 μm, and the depth of the dot was about 600 μm.

Comparative Example 1 The procedure was the same as in Example 1, except that no paint was applied to the surface of the metal material 10.
An identification symbol composed of a dot pattern was formed on the surface of the metal material 10.

FIG. 2A shows a photograph of the identification symbol marked by the method of Comparative Example 1. Also, in FIG.
2 shows a photograph of an identification symbol marked by the method of Example 1. In the case of Comparative Example 1, as shown in FIG. 2A, it can be seen that the visibility of the identification symbol is poor because the dot and the skin color of the steel material are similar. On the other hand, in the case of the first embodiment, as shown in FIG. 2B, after the white coating film 12 is formed on the surface of the metal material 10, marking of the identification symbol is performed. It turns out that it is excellent.

FIG. 2 (c) shows a photograph of the surface of the steel material in which the identification code is marked using the method of Example 1 and the coating film 12 is forcibly peeled off using a wire brush. From FIG. 2C, it can be seen that the visibility of the identification symbol is lowered by peeling off the coating film 12, but the marked identification symbol is not lost.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the gist of the present invention. is there.

[0049]

According to the laser marking method of the present invention, after a coating film is formed on a surface of a metal material, the coating film is removed along a predetermined pattern by laser irradiation, and at the same time, a predetermined Is formed, so that it is possible to form an identification symbol having excellent visibility and durability.

When the pattern formed by laser irradiation is a dot pattern, there is an effect that marking can be performed efficiently. Also,
By using a paint containing a surface treatment agent for forming fine irregularities on the surface of the metal material and a pigment having a luminance difference from the surface of the metal material, as a paint for forming the coating film, There is an effect that durability and visibility are improved.

Further, in the case where the metal material is a hot material, if the oxide film formed on the surface of the metal material is removed before forming the coating film, the disappearance of the identification symbol due to the drop of the oxide film is eliminated. There is an effect that it can be avoided.

[Brief description of the drawings]

FIG. 1 is a process chart showing a laser marking method according to an embodiment of the present invention.

FIG. 2 (a) is a drawing substitute photograph of an identification symbol (Comparative Example 1) directly marked on a steel material surface, FIG. 2 (b)
Is a drawing substitute photograph of the identification symbol (Example 1) marked from above the coating film formed on the steel material surface, FIG. 2 (c).
Is a drawing substitute photograph of the surface of the steel material from which the coating film was peeled after marking the identification symbol from above the coating film.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Metal material 10a Oxide film 12 Coating film 14 Depression

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. 7 Identification symbol FI Theme coat ゛ (Reference) B41M 5/26 B23K 103: 16 // B23K 103: 16 B41M 5/26 S (72) Inventor Charlie Els Albright 10580 Riverside Drive, Powell, Ohio, United States, 43065 F-term (reference) 2H111 HA14 HA22 HA32 4D075 BB02X BB20Z BB23Y BB45Z BB48Z BB92Z BB93Y CA13 CA33 CA47 CB04 CB33 DA03 DA06 DA10 DA15 DA20 DB01 DC08 DB11 EC01 EC01

Claims (7)

[Claims]
1. A coating film forming step of forming a coating film on a surface of a metal material, and irradiating a laser to the surface of the coating film according to a predetermined pattern, and removing the coating film at a portion irradiated with the laser. And a marking step of forming a concave portion on the surface of the metal material at the same time.
2. The laser marking method according to claim 1, wherein the pattern is a dot pattern for displaying information by a combination of dots.
3. The laser marking method according to claim 1, wherein the recess has a depth of 100 μm or more and 1000 μm or less.
4. The method according to claim 1, wherein the coating film forming step comprises applying a paint containing at least a surface treatment agent for forming fine irregularities on the surface of the metal material and a pigment having a luminance difference with respect to the surface of the metal material. 4. The laser marking method according to claim 1, wherein the method is applied to a surface of a material.
5. The coating film forming step includes forming a coating film having a thickness of 10 to 200 μm on the surface of the metal material.
The laser marking method according to claim 4, wherein the coating is applied.
6. The metal material has a temperature of 200 to 1
The laser marking method according to any one of claims 1 to 5, wherein the temperature is 000 ° C.
7. The laser marking method according to claim 6, further comprising a descaling step of removing an oxide film formed on a surface of the metal material before the coating film forming step.
JP2001161146A 2001-05-29 2001-05-29 Method for laser marking Pending JP2002346633A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2001161146A JP2002346633A (en) 2001-05-29 2001-05-29 Method for laser marking

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2001161146A JP2002346633A (en) 2001-05-29 2001-05-29 Method for laser marking

Publications (1)

Publication Number Publication Date
JP2002346633A true JP2002346633A (en) 2002-12-03

Family

ID=19004466

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2001161146A Pending JP2002346633A (en) 2001-05-29 2001-05-29 Method for laser marking

Country Status (1)

Country Link
JP (1) JP2002346633A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006065490A (en) * 2004-08-25 2006-03-09 Jfe Steel Kk Quality control method and quality control system for tailored blank
JP2012139698A (en) * 2010-12-28 2012-07-26 Jfe Steel Corp Laser marking method
JP2012139701A (en) * 2010-12-28 2012-07-26 Jfe Steel Corp Laser marking method
JP2013066925A (en) * 2011-09-26 2013-04-18 Jfe Steel Corp Laser marking method
US8508097B2 (en) * 2006-05-25 2013-08-13 Mitsubishi Electric Corporation Stator of electric rotating machine
JP2017030315A (en) * 2015-08-06 2017-02-09 日東工業株式会社 Grid-scaled coated steal panel and manufacturing method for the same

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006065490A (en) * 2004-08-25 2006-03-09 Jfe Steel Kk Quality control method and quality control system for tailored blank
US8508097B2 (en) * 2006-05-25 2013-08-13 Mitsubishi Electric Corporation Stator of electric rotating machine
JP2012139698A (en) * 2010-12-28 2012-07-26 Jfe Steel Corp Laser marking method
JP2012139701A (en) * 2010-12-28 2012-07-26 Jfe Steel Corp Laser marking method
JP2013066925A (en) * 2011-09-26 2013-04-18 Jfe Steel Corp Laser marking method
JP2017030315A (en) * 2015-08-06 2017-02-09 日東工業株式会社 Grid-scaled coated steal panel and manufacturing method for the same

Similar Documents

Publication Publication Date Title
CA2850174C (en) Can ends having machine readable information
US10118729B2 (en) Decorated beverage can tabs
US20130143013A1 (en) Method and apparatus for reliably laser marking articles
EP1853427B1 (en) Printing plastic containers with digital images
CN1229763C (en) Sign forming method
EP0688678B1 (en) One-sheet laser label
US5238778A (en) Method of forming printing plates by heat transfer
US6691618B2 (en) Chemical imaging of a lithographic printing plate
EP1050604B1 (en) Method for removing an aluminide coating from a substrate
TWI326639B (en) Coloured laser marking
US6168100B1 (en) Method for producing embossed metallic flakelets
US4994639A (en) Methods of manufacture and surface treatment using laser radiation
US5552574A (en) Method for the marking of a connector of a chip card with a laser beam
AU2005222743B2 (en) Process and apparatus for providing identity marks on security documents
EP0054840A2 (en) Method and apparatus for providing an identifying indicium to a diamond
JP6117558B2 (en) Ink for inkjet printing, printing cylindrical container, and method for producing the same
ES2181653T5 (en) Procedure for the manufacture of a multi-paper printed circuit card and composite sheet for use thereof.
KR101584691B1 (en) Method and system for manufacturing intaglio printing plates for the production of security papers
Leone et al. AISI 304 stainless steel marking by a Q-switched diode pumped Nd: YAG laser
US20080011852A1 (en) Laser-based method and system for processing targeted surface material and article produced thereby
US6169266B1 (en) Etching of multi-layered coated surfaces to add graphic and text elements to an article
EP0443639A1 (en) Improvements in laser marking of plastic articles
EP2322353B1 (en) Method for applying a permanent process mark to a product, particularly glass
CA1321625C (en) Process and apparatus for micro-pattern forming on roll surface, metal sheets for pressworking prepared by the roll, and the method of preparing same
US20040013969A1 (en) Colored inscription and marking of plastics and surface coatings