WO2000053686A1 - Retroreflective inks - Google Patents
Retroreflective inks Download PDFInfo
- Publication number
- WO2000053686A1 WO2000053686A1 PCT/GB2000/000509 GB0000509W WO0053686A1 WO 2000053686 A1 WO2000053686 A1 WO 2000053686A1 GB 0000509 W GB0000509 W GB 0000509W WO 0053686 A1 WO0053686 A1 WO 0053686A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- plastisol
- ink
- microbeads
- ink according
- beads
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/12—Reflex reflectors
- G02B5/126—Reflex reflectors including curved refracting surface
- G02B5/128—Reflex reflectors including curved refracting surface transparent spheres being embedded in matrix
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D11/00—Inks
- C09D11/02—Printing inks
Definitions
- This invention relates to retroreflective inks, methods for making retroreflective inks and methods for printing with retroreflective inks.
- Retroreflective inks which comprise retroreflective materials, usually hemispherically silvered microbeads, in suspension in a liquid medium.
- the liquid medium usually comprises a binder in a solvent or water.
- the solvent or water evaporates, leaving the beads partly exposed, a necessary condition for retroreflection. Because there is minimal volatile component in a plastisol ink, there is little or no change in the thickness of the printed layer on curing, and the thickness of the polymer deposited is commensurate with the bead diameter.
- Retroreflective microbeads added to conventional plastisol inks tend to remain covered by the polymer after printing and curing, and no significant retroreflectivity is achieved.
- the present invention provides retroreflective plastisol inks.
- the invention provides a retroreflective ink comprising a plastisol containing microbeads treated with a substance that causes them to float in a layer of the plastisol whereby the beads on printing rise to the surface of the printed plastisol layer where they are exposed for retroreflectivity.
- the substance may comprise a fluorosilane.
- the beads may be treated with an aminosilane.
- Retroreflective inks may be made using unmetallised microbeads. Where silvered beads, e.g. beads hemispherically coated with aluminium, are used, the beads may be pretreated prior to metallisation with a metal adhesion enhancer, such, for example, as stannous chloride.
- a metal adhesion enhancer such, for example, as stannous chloride.
- a blocked isocyanate may be added in the plastisol formulation, such, for example, as Trixene BI 7770.
- the plastisol may comprise polyvinyl chloride (PVC).
- PVC polyvinyl chloride
- the ink may contain a thickening agent.
- the ink may contain a surfactant.
- the ink may comprise 30-50% w/w of microbeads and may also contain a pigment, possibly up to 5% w/w of pigment, which may comprise a metallic pigment.
- the invention also comprises a method for making a retroreflective ink comprising a plastisol, comprising
- the substance may comprise a fluorosilane.
- deionised water (6 parts by weight) is added to isopropyl alcohol (114 parts by weight) and the pH adjusted to 5.0 ⁇ 0.5 with acetic acid, fluorosilane (1.1 parts by weight) added and the solution stirred to hydrolyse the silane, and the resulting solution used to treat the microbeads.
- the microbeads may be treated with an aminosilane, which may be added (1 part by weight) to the fluorosilane solution after the fluorosilane is hydrolysed and the solution stirred again before being used to treat the microbeads.
- 60 parts by weight of the solution may be added to 1000 parts by weight of microbeads so as to wet them thoroughly, the solvent then being evaporated off, after which the microbeads may be heated, cooled and sieved.
- Metallised microbeads may be pretreated with stannous chloride before metallisation.
- the treated microbeads may be mixed with a plastisol formulation comprising a base plastisol, a thickening agent, a surfactant and a blocked isocyanate.
- the invention also comprises a method for printing comprising applying an ink as above disclosed to a substrate and curing the print. Where the ink contains a blocked isocyanate, the print is cured at above the unblocking temperature thereof.
- Fluorosilane FC 405 manufactured by 3M Corporation and aminosilane Z-6020 manufactured by Dow Corning are suitable for use in the inks.
- Trixene BI 7770 Blocked isocyanates other than the Trixene BI 7770 may be used, for example Trixene BI 7960 (unblocking temperature 120°C) and Trixene BI 7960 (90 °C), but the Trixene BI 7770 has an unblocking temperature of 160° C above which the print must be heated in any event, e.g for two minutes, to ensure adequate fusion of the plastisol.
- the beads themselves are desirably 40-60 micron beads in order to pass through conventional printing screens. For optimum reflectivity, the refractive index of the glass should be close to 1.9.
- the fluorosilane reaction appears to occur mainly on the uncoated glass surface, causing a greater proportion of the beads than would be expected on random orientation to face in the required direction for retroreflective, namely uncoated side facing outwards.
- Deionised water (6g) is added to isopropyl alcohol (114g) and the pH adjusted to 5.0 ⁇ 0.5 with acetic acid.
- Fluorosilane FC 405 (l.lg) is added and the solution stirred for 5-15 minutes to hydrolyse the silane.
- the aminosilane Z-6020 (l.Og) is added and the solution stirred for a further 30 minutes.
- Coloured prints can be obtained by including plastisol compatible pigments; loss of reflectivity is minimal with pigment levels below about 5% w/w. Metallic pigments can be used to produce attractive visual effects.
Landscapes
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Wood Science & Technology (AREA)
- Organic Chemistry (AREA)
- Inks, Pencil-Leads, Or Crayons (AREA)
Abstract
There is disclosed a retroreflective ink comprising a plastisol containing microbeads treated with a substance that causes them to float in a layer of the plastisol whereby the beads on printing rise to the surface of the printed plastisol layer where they are exposed for retroreflectivity.
Description
RETROREFLECTIVE INKS
This invention relates to retroreflective inks, methods for making retroreflective inks and methods for printing with retroreflective inks.
Retroreflective inks are known which comprise retroreflective materials, usually hemispherically silvered microbeads, in suspension in a liquid medium. The liquid medium usually comprises a binder in a solvent or water. On printing, the solvent or water evaporates, leaving the beads partly exposed, a necessary condition for retroreflection. Because there is minimal volatile component in a plastisol ink, there is little or no change in the thickness of the printed layer on curing, and the thickness of the polymer deposited is commensurate with the bead diameter. Retroreflective microbeads added to conventional plastisol inks tend to remain covered by the polymer after printing and curing, and no significant retroreflectivity is achieved.
The present invention provides retroreflective plastisol inks.
The invention provides a retroreflective ink comprising a plastisol containing microbeads treated with a substance that causes them to float in a layer of the plastisol whereby the beads on printing rise to the surface of the printed plastisol layer where they are exposed for retroreflectivity.
The substance may comprise a fluorosilane.
The beads may be treated with an aminosilane.
Retroreflective inks may be made using unmetallised microbeads. Where silvered beads, e.g. beads hemispherically coated with aluminium, are used, the beads
may be pretreated prior to metallisation with a metal adhesion enhancer, such, for example, as stannous chloride.
A blocked isocyanate may be added in the plastisol formulation, such, for example, as Trixene BI 7770.
The plastisol may comprise polyvinyl chloride (PVC). The ink may contain a thickening agent. The ink may contain a surfactant.
The ink may comprise 30-50% w/w of microbeads and may also contain a pigment, possibly up to 5% w/w of pigment, which may comprise a metallic pigment.
The invention also comprises a method for making a retroreflective ink comprising a plastisol, comprising
treating microbeads with a substance that causes them to float in a layer of the plastisol
• incorporating the so treated microbeads in the plastisol
The substance may comprise a fluorosilane.
In a particular method, deionised water (6 parts by weight) is added to isopropyl alcohol (114 parts by weight) and the pH adjusted to 5.0 ± 0.5 with acetic acid, fluorosilane (1.1 parts by weight) added and the solution stirred to hydrolyse the silane, and the resulting solution used to treat the microbeads.
The microbeads may be treated with an aminosilane, which may be added (1 part by weight) to the fluorosilane solution after the fluorosilane is hydrolysed and the solution stirred again before being used to treat the microbeads.
60 parts by weight of the solution may be added to 1000 parts by weight of microbeads so as to wet them thoroughly, the solvent then being evaporated off, after which the microbeads may be heated, cooled and sieved.
Metallised microbeads may be pretreated with stannous chloride before metallisation.
The treated microbeads may be mixed with a plastisol formulation comprising a base plastisol, a thickening agent, a surfactant and a blocked isocyanate.
The invention also comprises a method for printing comprising applying an ink as above disclosed to a substrate and curing the print. Where the ink contains a blocked isocyanate, the print is cured at above the unblocking temperature thereof.
Fluorosilane FC 405 manufactured by 3M Corporation and aminosilane Z-6020 manufactured by Dow Corning are suitable for use in the inks.
Blocked isocyanates other than the Trixene BI 7770 may be used, for example Trixene BI 7960 (unblocking temperature 120°C) and Trixene BI 7960 (90 °C), but the Trixene BI 7770 has an unblocking temperature of 160° C above which the print must be heated in any event, e.g for two minutes, to ensure adequate fusion of the plastisol.
The beads themselves are desirably 40-60 micron beads in order to pass through conventional printing screens. For optimum reflectivity, the refractive index of the glass should be close to 1.9.
The fluorosilane reaction appears to occur mainly on the uncoated glass surface, causing a greater proportion of the beads than would be expected on random orientation to face in the required direction for retroreflective, namely uncoated side facing outwards.
Without the aminosilane treatment, the fluorosilane treated beads are only poorly held in the PVC matrix and are easily lost on washing. The aminosilane treatment, together with the presence of the blocked isocyanate in the plastisol composition, gives satisfactory washfastness, however.
Silane treatment solution preparation
Deionised water (6g) is added to isopropyl alcohol (114g) and the pH adjusted to 5.0 ± 0.5 with acetic acid. Fluorosilane FC 405 (l.lg) is added and the solution stirred for 5-15 minutes to hydrolyse the silane. The aminosilane Z-6020 (l.Og) is added and the solution stirred for a further 30 minutes.
Bead Treatment
To 1 kg of metallised beads (pretreated with stannous chloride before metallising to improve adhesion of the 0.03 micron thick aluminium layer) is added 60g of the isopropyl alcohol solution ensuring that the beads are completely wetted. The solvent is evaporated off, and the beads heated for 1 hour at 120°C. The treated beads are finally cooled and sieved.
Base plastisol formulation
PVC powder 600g
Plasticiser 450g
Cd/Zn Stabiliser 12g
Plastisol ink formulation
% w/w
Base plastisol 53.24
Thickening agent 0.16
Surfactant 0.60
Blocked isocyanate 6.00
Fluorosilane/amino-silyated metallised beads 40.00
Coloured prints can be obtained by including plastisol compatible pigments; loss of reflectivity is minimal with pigment levels below about 5% w/w. Metallic pigments can be used to produce attractive visual effects.
Claims
1. A retroreflective ink comprising a plastisol containing microbeads treated with a substance that causes them to float in a layer of the plastisol whereby the beads on printing rise to the surface of the printed plastisol layer where they are exposed for retroreflectivity.
2. An ink according to claim 1, in which the substance comprises a fluorosilane.
3. An ink according to claim 2, in which the beads are treated with an amino silane.
4. An ink according to any one of claims 1 to 3, in which the beads are hemispherically metallised.
5. An ink according to claim 4, in which the beads are hemispherically coated with aluminium.
6. An ink according to claim 4 or claim 5, in which the beads have been pretreated prior to metallisation with a metal adhesion enhancer.
7. An ink according to claim 6, in which the metal adhesion enhancer comprises stannous chloride.
8. An ink according to any one of claims 1 to 7, in which a blocked isocyanate is included in the plastisol formulation.
9. An ink according to claim 8, in which the blocked isocyanate comprises Trixene BI 7770.
10. An ink according to any one of claims 1 to 9, in which the plastisol comprises PVC.
11. An ink according to any one of claims 1 to 10, containing a thickening agent.
12. An ink according to any one of claims 1 to 11, comprising a surfactant.
13. An ink according to any one of claims 1 to 12, containing 30-50% w/w of microbeads.
14. An ink according to any one of claims 1 to 14, containing a pigment.
15. An ink according to claim 14, containing up to 5% w/w of pigment.
16. An ink according to claim 14 or claim 15, containing metallic pigment.
17. An method for making a retroflective ink comprising a plastisol comprising
treating microbeads with a substance that causes them to float in a layer of the plastisol
incorporating the so treated microbeads in the plastisol
18. A method according to claim 17, in which the substance comprises a fluorosilane.
19. A method according to claim 18, in which de-ionised water (6 parts by weight) is added to isopropyl alcohol (114 parts by weight) and the pH adjusted to 5.0 ± 0.5 with acetic acid, fluorosilane (1.1 parts by weight) added and the solution stirred to hydrolyse the silane and the resulting solution used to treat the microbeads.
20. A method according to any one of claims 17 to 19, in which the microbeads are treated with an aminosilane.
21. A method according to claim 19, in which the aminosilane is added (1 part by weight) to the solution after the fluorosilane is hydrolysed and the solution stirred again.
22. A method according to claim 19 or claim 21, in which 60 parts by weight of the solution are added to 1000 parts by weight of microbeads so as to wet them thoroughly and the solvent evaporated off.
23. A method according to claim 22, in which the microbeads are heated after the solvent has evaporated, cooled and sieved.
24. A method according to any one of claims 17 to 23 , in which the microbeads are metallised, pretreated before metallisation with stannous chloride.
25. A method according to any one of claims 17 to 24, in which the beads are mixed into a plastisol formulation comprising a base plastisol, a thickening agent, a surfactant and a blocked isocyanate.
26. A method for printing comprising applying an ink according to any one of claims 1 to 16 or made by a method according to any one of claims 17 to 25 to a substrate and curing the print.
27. A method for printing according to claim 26, in which the ink contains a blocked isocyanate having an unblocking temperature and curing the print at above the unblocking temperature thereof.
28. A print made with an ink according to any one of claims 1 to 16 or an ink made by a method according to any one of claims 17 to 25 or a print made by a method according to claim 26 or claim 27.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AU25588/00A AU2558800A (en) | 1999-03-05 | 2000-02-16 | Retroreflective inks |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9904972.8 | 1999-03-05 | ||
| GB9904972A GB2347428A (en) | 1999-03-05 | 1999-03-05 | Retroreflective inks |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2000053686A1 true WO2000053686A1 (en) | 2000-09-14 |
Family
ID=10848943
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/GB2000/000509 WO2000053686A1 (en) | 1999-03-05 | 2000-02-16 | Retroreflective inks |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU2558800A (en) |
| GB (1) | GB2347428A (en) |
| WO (1) | WO2000053686A1 (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2214915A (en) * | 1988-02-19 | 1989-09-13 | Glaverbel | Marking comprising glass beads in a matrix, kit for same, and processes of treating the beads and of forming the marking |
| GB2241179A (en) * | 1990-02-21 | 1991-08-28 | Glaverbel | Coated glass microbeads and pigment for synthetic polymeric material |
| US5837347A (en) * | 1995-09-15 | 1998-11-17 | Minnesota Mining And Manufacturing Company | Retroreflective transfer sheet and applique |
-
1999
- 1999-03-05 GB GB9904972A patent/GB2347428A/en not_active Withdrawn
-
2000
- 2000-02-16 WO PCT/GB2000/000509 patent/WO2000053686A1/en active Application Filing
- 2000-02-16 AU AU25588/00A patent/AU2558800A/en not_active Abandoned
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2214915A (en) * | 1988-02-19 | 1989-09-13 | Glaverbel | Marking comprising glass beads in a matrix, kit for same, and processes of treating the beads and of forming the marking |
| GB2241179A (en) * | 1990-02-21 | 1991-08-28 | Glaverbel | Coated glass microbeads and pigment for synthetic polymeric material |
| US5837347A (en) * | 1995-09-15 | 1998-11-17 | Minnesota Mining And Manufacturing Company | Retroreflective transfer sheet and applique |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9904972D0 (en) | 1999-04-28 |
| AU2558800A (en) | 2000-09-28 |
| GB2347428A (en) | 2000-09-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2129983C (en) | Launderable retroreflective applique with improved retention of retroreflective elements | |
| US6319613B1 (en) | Coating solution for forming a film for cutting off solar radiation and the film formed therefrom | |
| US9116301B2 (en) | Durable light-polarizing articles and method of making the same | |
| JP3300400B2 (en) | Washable retroreflective applique with colorant | |
| JP3811741B2 (en) | Water-dispersible coating with silica particle surface coated with metal oxide | |
| KR100382824B1 (en) | Method for transferring transparent conductive film | |
| US4173490A (en) | Coating composition | |
| JPH06265830A (en) | Colored plastic lens | |
| US4779957A (en) | Colored liquid crystal electro-optical device having a buffer layer and method for manufacturing the same | |
| EP1144524B1 (en) | Retroreflective inks | |
| WO1998030923A1 (en) | Optical element, a display device provided with said optical element, and a method of manufacturing the optical element | |
| KR100384730B1 (en) | Coating fluid for forming hard coating and substrates covered with hard coating | |
| KR100725137B1 (en) | Aqueous black enamel composition for glass substrates, glass sheets and laminated glazing coated with the composition | |
| US11911997B2 (en) | Method for obtaining a laminated curved glazing | |
| JP2972827B2 (en) | UV absorbing transparent body | |
| CN1285859A (en) | Water-based paint including glass particulate | |
| KR20010089990A (en) | Providing Organic Paint On a Glass Sheet | |
| EP1013726A1 (en) | High solids water-based ceramic paint | |
| KR19990087487A (en) | Water-based paints for glass sheets | |
| WO2000053686A1 (en) | Retroreflective inks | |
| CA2190195A1 (en) | Method of forming a protective layer on a copper-free reflective metal layer | |
| US12054421B2 (en) | Method for producing a curved laminated glazing | |
| JP3871373B2 (en) | How to make display | |
| KR20030044981A (en) | Substrate having hard coating membrane | |
| JP4104353B2 (en) | Paint composition |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AL AM AT AU AZ BA BB BG BR BY CA CH CN CR CU CZ DE DK DM EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW |
|
| AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): GH GM KE LS MW SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG |
|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
| DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
| WWE | Wipo information: entry into national phase |
Ref document number: 09914908 Country of ref document: US |
|
| REG | Reference to national code |
Ref country code: DE Ref legal event code: 8642 |
|
| 122 | Ep: pct application non-entry in european phase |