Method for the production of a polycarbonate laminate

Abstract

The invention relates to the use of a preparation comprising A) 0.1 to 20 wt % of a binding agent with a polycarbonate derivative based on a geminally disubstituted dihydroxydiphenyl cycloalkane, B) 30 to 99.9 wt % of an organic solvent or of a mixture of solvents, C) 0 to 10 wt %, referred to dry mass, of a dye or of a mixture of dyes, D) 0 to 10 wt % of a functional material or of a mixture of functional materials, E) 0 to 30 wt % of additive and/or auxiliary substances, or of a mixture of such substances, the relative amounts of the components A) to E) always totaling 100 wt %, as an ink jet printing dye.

Claims

1. A method for making a structure with at least a first polymer layer and a second polymer layer, each made from a polycarbonate polymer containing repeating units derived from bisphenol A, wherein on the first polymer layer an ink jet printing layer is arranged, comprising the following steps: a) ink jet printing a preparation, the preparation comprising (1) a binding agent comprising 0.1 to 20 wt % of the polycarbonate polymer with a polycarbonate derivative based on a geminally disubstituted dihydroxydiphenyl cycloalkane, wherein the polycarbonate derivative is based on 4,4-(3,3,5-trimethylcyclohexane-1,1-diyl)diphenol and has a softening temperature of 185 C. or less, and wherein the polycarbonate polymer in the ink jet printing preparation is different from the polycarbonate polymer in the first and second polymer layer; (2) 30 to 99.9 wt % of a solvent or of a mixture of solvents, (3) 0 to 10 wt %, referred to dry mass, of a dye or of a mixture of dyes, (4) 0 to 10 wt % of a functional material or of a mixture of functional materials, and (5) 0 to 30 wt % of additive and/or auxiliary substances, or of a mixture of such substances, wherein the relative amounts of the components (1) to (5) always totals 100 wt %, as an ink jet printing dye directly on at least one partial region of the first polymer layer, b) optionally, drying the ink jet printing layer, c) after step a) or step b), placing the second polymer layer on the first polymer layer, covering the ink jet printing layer, and laminating the first polymer layer and the second polymer layer with each other under pressure, at a temperature of 150 C. to 180 C. 9 for a defined time.

2. The method according claim 1, wherein each of the first polycarbonate layer and the second polycarbonate layer have a glass temperature Tg of more than 145 C.

3. The method according to claim 1, wherein the thickness of each of the first polycarbonate layer and of the second polycarbonate layer is up to 1,000 m.

4. The method according to claim 1, wherein the thickness, measured in directions orthogonal to a main face of a polycarbonate layer, of the ink jet printing layer is in the range from 0.01 to 10 m.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following, the invention is described in more detail with reference to nonlimiting embodiments. There are:

(2) FIG. 1: a representation of a test print area, and

(3) FIG. 2: details of a portrait of a person made by a method according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

Example 1: Making Polycarbonate Derivatives to be Used According to the Invention

Example 1.1: Making a First Polycarbonate Derivative

(4) 205.7 g (0.90 mole) bisphenol A (2,2-bis-(4-hydroxyphenyl)-propane, 30.7 g (0.10 mole) 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexane, 336.6 g (6 mole) KOH and 2,700 g water are dissolved in an inert gas atmosphere under stirring. Then a solution of 1.88 g phenol in 2,500 ml methylene chloride is added. Into the well stirred solution, 198 g (2 mole) phosgene are introduced at pH 13 to 14 and 21 to 25 C. Then 1 ml ethylpiperidine is added and stirred for another 45 min. The bisphenolate-free aqueous phase is separated, after acidification with phosphoric acid, the organic phase is washed neutrally with water and freed from solvent.

(5) The polycarbonate derivative had a relative solution viscosity of 1.255. The glass temperature was determined to be 157 C. (DSC).

Example 1.2: Making a Second Polycarbonate Derivative

(6) In an analogous manner to Example 1, a mixture of 181.4 g (0.79 mole) bisphenol A and 63.7 g (0.21 mole) 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexane was reacted to the polycarbonate derivative.

(7) The polycarbonate derivative has a relative solution viscosity of 1.263. The glass temperature was determined to be 167 C. (DSC).

Example 1.3: Making a Third Polycarbonate Derivative

(8) In an analogous manner to Example 1, a mixture of 149.0 g (0.65 mole) bisphenol A (2,2-bis-(4-hydroxyphenyl)-propane and 107.9 g (0.35 mole) 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexane was reacted to the polycarbonate derivative.

(9) The polycarbonate derivative had a relative solution viscosity of 1.263. The glass temperature was determined to be 183 C. (DSC).

Example 1.4: Making a Fourth Polycarbonate Derivative

(10) In an analogous manner to Example 1, a mixture of 91.6 g (0.40 mole) bisphenol A and 185.9 g (0.60 mole) 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexane was reacted to the polycarbonate derivative.

(11) The polycarbonate derivative had a relative solution viscosity of 1.251. The glass temperature was determined to be 204 C. (DSC).

Example 1.5: Making a Fifth Polycarbonate Derivative

(12) As in Example 1, a mixture of 44.2 g (0.19 mole) bisphenol A and 250.4 g (0.81 mole) 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexane was reacted to the polycarbonate.

(13) The polycarbonate derivative had a relative solution viscosity of 1.248. The glass temperature was determined to be 216 C. (DSC).

Example 2: Making a Liquid Preparation being Suitable for Making an Ink Jet Printing Dye

(14) A liquid preparation was made from 17.5 weight parts of the polycarbonate derivative from Example 1.3 and 82.5 weight parts of a solvent mixture according to Table I.

(15) TABLE-US-00001 TABLE I Mesitylene 2.4 1-methoxy-2-propanolacetate 34.95 1,2,4-trimethylbenzene 10.75 Ethyl-3-ethoxypropionate 33.35 Cumol 0.105 Solvent naphtha 18.45

(16) A colorless, highly viscous solution with a solution viscosity of 800 mPa.Math.s at ambient temperature was obtained.

Example 3: Making a First Ink Jet Printing Dye Used According to the Invention

(17) In a 50 mL wide-neck thread glass, 4 g polycarbonate solution of Example 2 and 30 g of the mixture of solvents of Example 2 were homogenized with a magnetic stirrer. A colorless, low-viscous solution with a solution viscosity of 1.67 mPa.Math.s at ambient temperature was obtained.

(18) The surface tension of this basic ink was determined with an OEG Surftens measuring system according to the pendant drop method to be 21.41.9 mN/m.

(19) An addition of a pigment or of a dye was not made, since this ink only served for use in the test print of Example 6.

Example 4: Making a Second Ink Jet Printing Dye Used According to the Invention

(20) In an analogous manner to Example 3, 10 g polycarbonate solution of Example 2 and 32.5 g mixture of solvents of Example 2 were homogenized with a magnetic stirrer (4% PC solution). A colorless, low-viscous solution with a solution viscosity of 5.02 mPa.Math.s at 20 C. was obtained. Here, too, no addition of a pigment or dye was made, since this ink only served for use in the test print of Example 7.

Example 5: Making a Third Ink Jet Printing Dye Used According to the Invention

(21) A polycarbonate solution according to Example 4 was prepared and additionally reacted with approx. 2% pigment Black 28. An ink results, by means of which black & white images can be printed on polycarbonate films, and reference is made to Example 8.

Example 6: Drop Size when Printing with an Ink According to Example 3

(22) The solution of Example 3 was transferred by filtration into a printer cartridge and printed with an ink jet printer FUJIFILM-Dimatix DMP 2800 under variation of various printing parameters. The used printer is a so-called drop-on-demand system, wherein the drop generation is made by a piezoelectric printing head. The DMP 2800 has a stroboscopic image recording system, by means of which the drop formation and the drop path can be investigated. The prints were dried at 100 C. for 30 min. Depending on the base, different drop sizes can be achieved, as is shown in Table 1.

(23) TABLE-US-00002 TABLE 1 Polycarbonate Velin Substrate Glass (smooth) paper individual ~74 m ~85 m ~100 m drops

(24) As expected, on sucking bases, the drops will be absorbed more than on non-sucking bases such as glass or plastic.

Example 7: Determination of the Layer Thickness of an Ink Jet Printing Layer

(25) An ink according to Example 4 was printed on glass substrates. The so-called drop distance (pitch, see also FIG. 1) varied from 10 to 45 The prints were again dried at 100 C. for 30 min. Then layer thickness measurements were made (Arithmetic Step Height=ASH) with a profilometer (Dektak 6M; 12.5 m Stylus), and the results are listed in Table 2.

(26) TABLE-US-00003 TABLE 2 Pitch ASH [nm] 10 m 685 30 m 100 45 m 27

(27) By the drop distance alone, the layer thickness can be adjusted in a wide range.

Example 8: Making an Image and Verifying the Optical Quality after the Lamination

(28) Using the ink of Example 5, a portrait of a person was printed on Makrofol 4-4. The thus produced portrait was laminated together with transparent Makrofol 6-2-films at temperatures >180 C., pressures >5 bar and times >10 min to form a structure of approx. 800 m thickness. Light-microscopic investigations before and after the lamination were made, in order to evaluate the edge definition of individual pixels. The results are shown in FIG. 2. There are shown on top in FIG. 2 colored printing images (top) and thereunder the same printing images, however after conversion into black & white. On the left side, there is shown a detailed representation of the ink jet printing layer made according to the invention before the lamination. On the right side, the same detailed representation is shown after the lamination. It can be seen that the pixel patterns are maintained also after the lamination in nearly the same resolution. The horizontal lines result from the overlapping sections of the individual ink jet nozzles of the printing head and have therefore nothing to do with the ink according to the invention.

(29) Apart from that, an optical investigation of the structure did not show any recognizable phase limit. The structure is a monolithic block excellently resisting to delamination.