KR19990071729A - Manufacturing method of color-marked object - Google Patents

Abstract

In a method of manufacturing a color-marked object that irradiates the surface of the object with laser light, the objects exhibit a maximum in their light absorption spectra at different wavelengths, at least at the locations where the marking is used, and their light under the influence of laser light. Consisting of a plastic composition containing at least three light-absorbing components that lose the absorbing capacity, wherein at least one light-absorbing component completely or partially loses its light-absorbing capacity and the laser light of said wavelength and intensity The marking is applied in the form of matrix dots by irradiating the surface of the object at the position of the matrix dots.

Description

Manufacturing method of color-marked object

The present invention relates to a method for producing a color-marked object by irradiating a laser light on the surface of the object.

The above method is known from WO94 / 12352. The patent application describes a method in which the surface of an object is irradiated under arbitrary selection conditions in which color-marking is obtained.

A disadvantage of the known method is that the color obtained is not chosen freely but by chance. Moreover, the marking can only obtain a limited number of colors.

It is an object of the present invention to provide a manufacturing method which does not have the above disadvantages.

Surprisingly, at least at the location where marking is used, the object is composed of a plastic composition containing at least three light-absorbing components that exhibit a maximum in the light absorption spectra at different wavelengths and lose the light-absorbing capacity under the influence of laser light, The marking was applied in the form of matrix dots by irradiating the surface of the object at the position of the matrix dots with the laser light of the wavelength and intensity and the period during which at least one light-absorbing component completely or partially lost its light-absorbing capacity. All.

In this way, markings are obtained in which the color is freely determined, the markings comprising different colors, and markings in different colors can be obtained on the surface of the same plastic composition. Moreover, the marking can be obtained at the surface of the same plastic composition in many different colors.

The matrix dots absorbed by the color-absorbing component have a color of light before the component completely or partially loses its light-absorbing capacity.

Light-absorbing components are understood as components having a chromatic color, such as dyes or pigments. It is understood that the light-absorbing component does not include white or black components such as titanium dioxide, chalk, barium sulfide, carbon black or iron sulfide.

It is essential that the light-absorbing components have little or no loss of their light-absorbing capacity at ordinary days. For this reason, the light-absorbing component has a color stability of at least 5, preferably at least 7 and in particular at least 7 on a wool scale (according to DIN 54003).

Examples of suitable light-absorbing constituents are magenta pigments in Irgalit Rubine 4 BP, cyan pigments in Irgalth Blue LGLD, or Chromopthal Yellow 6G. 6G) and Chromopthal Yellow 3G, two yellow pigments. Incidentally, most light-absorbing components lose their light-absorbing capacity in whole or in part when laser light is irradiated.

The manufacturing method of the present invention allows matrix dots to be applied on the surface in a simple manner.

Irradiation with laser light of a particular wavelength will reduce the light-absorption capacity of the light-absorbing component already selected, and the surface of the irradiated site will reflect colors that are no longer absorbed by that component. The brightness of the reflected color can be improved by increasing the intensity of the laser light or by extending the duration of the irradiation.

Marking of the preferred color is formed using many matrix dots on the surface.

It is also possible to use matrix dots of different colors side by side on the surface. For the observer, the color of the surface at the location of the matrix dots is a mixed color because the colors of the matrix dots are noticeable as if they were mixed. The method of color mixing in which the mixed colors are placed side by side is called the partitioning method. The mixed color is measured by the surface area ratio of the matrix dots and the luminance ratio of the color. As such, many mixed colors can be formed.

In this document, it is essential that the distance between the center band centers between dots is so small that individual matrix dots cannot be distinguished by the eye. Newspaper pictures are also colored in this manner.

As is known for color printing, very good results were obtained by using matrix dots of at least three different colors on the surface. This is achieved by irradiating the surface with laser light of at least three different wavelengths, one of the at least three light-absorbing components totally or partially losing their light-absorbing capacity at each wavelength. In this way, the use of at least three colors allows many different colors formed by mixing the colors in the appropriate amounts.

Mixed colors can be obtained in various forms. For example, varying the luminance of the color of the matrix dots for each; For example, a mixed color is obtained by irradiating a matrix dot of a specific color longer than other matrix dots. Optionally, the total area ratio of the other colors can be varied for each by forming one matrix dot that is larger than the other or by forming matrix dots of one color more than the other color. The matrix dots are round or square, but may also be triangular or linear, for example, to increase the overall reflection of the surface or to fill the surface well.

The color is characterized by first measuring the tristimulus value of the color according to ASTM standard E 308 and calculating therefrom a chromatic coordination that measures the position of the color within the CIE D65 color diagram (10 ° observer) as described in the above standard. Make up. As such, the color diagram is a graphical representation of all colors in the visible region.

The dispersive mixing technique allows colors formed in a color diagram that lies in area between points representing at least three different colors of matrix points in the color diagram. The dot forms a vertex of the area.

The process of the present invention, in which many other colors obtained are acceptable, involves the use of matrix dots, which are partially or completely overlaid. The color mixing technique is described as subtractive blending.

Preferably the color of the surface is measured by subtractive mixing of at least three different colored matrix points. The range of colors developed from the subtractive mixture is larger than in the case of distributive mixing in that it forms a color that lies outside of the area between the points representing at least three different colors of the matrix points in the color diagram.

In principle, the plastic composition comprises a thermosetting resin or thermoplastic resin or elastomer. It is particularly suitable for plastic compositions such as those mentioned in WO94 / 12352 to contain in plastics.

Preferably, the area between the points representing at least three different colors of the matrix points in the color diagram is chosen such that the light-absorbing component covers at least 10% of the area of the diagram.

Preferably the area covers at least 30%, preferably at least 75% of the diagram.

The wavelength of the laser light irradiated with the surface on the selected light-absorption component to dissipate its light-absorption capacity is easily measured by experiment.

Preferably, the wavelength of the laser light irradiating the surface is the maximum in the absorption spectrum of the light-absorbing component to lose its light-absorbing capacity. In this way good color brightness and very good selectivity are obtained.

Preferably, the manufacturing method of the present invention is carried out using one or more masks. The mask is not transmitted at the position irradiated to the surface or at the position not irradiated to the surface. Continuous irradiation with different masks and laser lights of different wavelengths on the surface allows for matrix dots of different colors to be applied to the surface quickly and easily.

The advantage is that the size of the matrix dots is measured by a mask, not by the diameter of the laser beam, and the surface can be irradiated with a large-diameter laser beam. As a result, the survey becomes shorter in time.

Preferably, the manufacturing method of the present invention is carried out with a variable mask.

Preferably, a mask made by an LCD screen is used.

In particular, it uses a PDLCD (Polymer Dispersed Liquid Crystal Display) mask, which does not absorb the non-transmissive laser beam but disperses the mask so that the mask does not warm up.

The advantage of the mask is that the desired mask can be computer-generated on the LCD screen or PDLCD screen and the surface can be irradiated through the mask. Subsequently, the second mask is corrected on the screen at the same position. This avoids possible positioning problems. Another advantage is that various masks can be replaced very quickly.

The manufacturing method of the present invention is carried out with a laser apparatus which simultaneously irradiates the surface of an object using at least three masks located adjacent to each other, in which the mask is projected onto the surface of an object on top of another one. Very good results were obtained by irradiating laser light of different wavelengths. The advantage is that the surface of the object is irradiated with a different mask in a single operation. In this method, there is an additional advantage that if the mask is variable, other markings can be used in succession very quickly. The same kind of assembly is known in video projection.

The method may also be practiced using a controlled laser beam of variable intensity. This offers greater flexibility in terms of the brightness of the color and the shape of the irradiated object.

Furthermore, a laser device having a suitable wavelength is preferable because a single laser device can be used to irradiate the surface with laser light of different wavelengths.

Preferably, the laser can emit light of different wavelengths comparable to the maximum of the absorption spectra of other light-absorbing components. And all possible colors can be formed with a single laser device.

Particularly preferred is the use of a laser device in which at least three laser beams of different wavelengths can be unified in a single fiber and can vary the intensity of each beam independently of the other beams. The advantage is that the surface of the object can be easily irradiated using one combined laser beam capable of emitting all colors. The above results have very high flexibility with respect to the type of marking used and the number of colors that can be selected.

Example 1

Acrylonitrile-butadiene-styrene copolymer (ABS) supplied by DSM in the Netherlands 1897 parts by weight of Ronfalin SFA-34, titanium dioxide pigment supplied by thiofine in the Netherlands as thiofine R41 (Tiofine) R41) 100 parts by weight and 1 part by weight of Irgalit Rubine 4BP with each magenta, cyan and yellow pigment supplied by Mesr Shiva Gay, Netherlands, Irgalit Blue LGLD A dry mixture is prepared from 1 part by weight) and 1 part by weight of Chromopthal yellow 6G.

The dry mixture is melted in a ZSK30 double-screw extruder supplied from Warner & Flyderer, Germany, kneaded at 260 ° C. and granulated. The particles were injection molded to produce plaques measured at 3.2 * 120 * 120mm in an Arburg Allrounder 320-90-750 injection molding machine at a temperature of 240 ° C. The colored pigment in the plaque absorbs visible light. The plaques are pale gray.

Marking is applied continuously on the surface by laser assembly. Laser assembly of variable wavelength is used (TMW laser assembly). The laser assembly includes an EEO-355 seeding laser and can be used as a pump laser for the GCR-230 / 50 Nd: YAG laser. The laser assembly also includes a MOPO 710 optical variable oscillator (OPO), which obtains single light from the last mentioned laser via frequency doubling optics (FDO). The assembly is supplied by Speccra-Physics, USA.

The following laser assemblies are selected:

Pulse Width: 5ns

Q-switching frequency: 30 Hz

Dot diameter: 3mm

Writing speed: 10mm / s

Line spacing: 0.66mm

Focal Length: + 80mm

Natural colors are applied to the test pieces by the above laser assembly according to the method described below. Natural colors are "red mask", "green mask" and "blue mask" by Corel Corporation's "Corel-Photoprint 5.0 for Hewlett Packard" in USA (selection: split channel RGB) Decompose to The black / white mask is printed onto the transparent body using the "Spectra Star GTx" from Messier General Parametric Corporation of USA. Position intersections are provided around the periphery for the correct position.

Subsequently, a "blue mask" is fitted onto the plaque and irradiated with a laser having a wavelength of 450 nm. The mask is then removed and replaced with a "green mask" in the upper exact position obtained by the "blue mask". Laser light having a wavelength of 530 nm is irradiated to the “green mask”. Finally, the "red mask" is fitted and irradiates a laser light having a wavelength of 650 nm. As soon as the last survey is completed, an indelible natural color is obtained in the plastic, and the range of natural colors is compared with the original.

Example 2

Hydroxy functional resin supplied from DSM resin in the Netherlands, 65.0 parts by weight of Uracron 474 CY, 20.8 parts by weight of Tolonate HDT EV 412 from Hums, Germany, from Aldrich, Belgium 0.6 parts by weight of dibutylindlaurate supplied, 10.0 parts by weight of Kronos CL 220, 1.2 parts by weight of chromophthal yellow 3G as yellow pigment supplied by Ciba Gauge of the Netherlands, supplied by BASF of the Netherlands Lacquer is made of coarse red beaker with 1.2 parts by weight of Paliogen Red L 3910 HD and 1.2 parts by weight of Orasol Blue GN, a blue pigment supplied by Ciba Gauge in the Netherlands. Is manufactured in. The lacquer is applied on an aluminum sheet with a film thickness of 50 micrometers. The lacquer film is grey. Markings are made on the lacquer film as described in Example 1.

The laser assembly for this experiment is as follows:

Pulse Width: 5ns

Q-switching frequency: 30 Hz

Dot diameter: 3mm

Writing speed: 25mm / s

Line spacing: 0.66mm

Focal Length: + 40mm

Claims (11)

In the method of manufacturing a color-marked object for irradiating laser light on the surface of the object, At least at the location where marking is used, the objects consist of a plastic composition containing at least three light-absorbing components which exhibit a maximum in their light absorption spectra at different wavelengths and which lose their light-absorbing capacity under the influence of laser light, The marking in the form of matrix dots is achieved by irradiating the surface of the object at the position of the matrix dots with the laser light of the wavelength and intensity and the period during which the at least one light-absorbing component completely or partially loses its light-absorbing capacity. A method of making a color-marked object, characterized in that it is applied. The method of claim 1, And the color of said surface is formed by subtractive mixing of at least three different colors of matrix points. The method of claim 1, And the color of the surface is formed by distributing and mixing the color of the matrix dots. The method according to claim 1, 2 or 3, And wherein the light-absorbing component is selected such that the area between the dots representing at least three different colors of the matrix point in the color diagram covers at least 10% of the area of the diagram. The method according to any one of claims 1 to 4, And the wavelength of the laser light irradiating the surface is at the maximum indicated by the absorption spectra of the other light-absorbing components. The method according to any one of claims 1 to 5, A process according to the invention, wherein the process of the invention is carried out using one or more masks. The method according to any one of claims 1 to 6, The manufacturing method of the invention is carried out using a variable mask. The method of claim 6, And said mask is produced by an LCD screen. The method of claim 6, A manufacturing method characterized by using a variable PDLCD (Polymer Dispersed Liquid Crystal Display) mask. The method according to any one of claims 1 to 9, A laser device that simultaneously irradiates the surface of an object using at least three masks located adjacent to each other, irradiates the surface, and the mask is laser light of different wavelengths in such a way that the image of the mask is projected onto the surface of the object on another. Manufacturing method characterized in that irradiated with. A laser device, characterized in that the intensity of each beam can be varied independently of other beams, wherein at least three laser beams of different wavelengths are singulated in a single fiber.