Copper phthalocyanine

Last updated
Copper phthalocyanine
Copper phthalocyanine.svg
Names
IUPAC name
(29H,31H-phthalocyaninato(2−)-N29,N30,N31,N32)copper(II)
Other names
Copper(II) phthalocyanine
Monastral blue
Phthalocyanine blue
Phthalo blue
Thalo blue
Pigment Blue 15
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.005.169 OOjs UI icon edit-ltr-progressive.svg
PubChem CID
UNII
  • InChI=1S/C32H16N8.Cu/c1-2-10-18-17(9-1)25-33-26(18)38-28-21-13-5-6-14-22(21)30(35-28)40-32-24-16-8-7-15-23(24)31(36-32)39-29-20-12-4-3-11-19(20)27(34-29)37-25;/h1-16H;/q-2;+2
    Key: XCJYREBRNVKWGJ-UHFFFAOYSA-N
  • C1=CC=C2C(=C1)C3=NC4=NC(=NC5=C6C=CC=CC6=C([N-]5)N=C7C8=CC=CC=C8C(=N7)N=C2[N-]3)C9=CC=CC=C94.[Cu+2]
Properties
C32H16CuN8
Molar mass 576.082 g·mol−1
Appearancedark blue solid
Related compounds
Other cations
Lead(II) phthalocyanine
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Phthalo blue
 
Copper Phtalocyanine Blue.JPG
Phthalocyanine blue pigment powder
Gtk-dialog-info.svg    Color coordinates
Hex triplet #000F89
sRGB B (r, g, b)(0, 15, 137)
HSV (h, s, v)(233°, 100%, 54%)
CIELChuv (L, C, h)(16, 61, 265°)
Source The Mother of All HTML Colo(u)r Charts
ISCC–NBS descriptor Vivid blue
B: Normalized to [0–255] (byte)
H: Normalized to [0–100] (hundred)

Copper phthalocyanine (CuPc), also called phthalocyanine blue, phthalo blue and many other names, is a bright, crystalline, synthetic blue pigment from the group of dyes based on phthalocyanines. Its brilliant blue is frequently used in paints and dyes. It is highly valued for its superior properties such as light fastness, tinting strength, covering power and resistance to the effects of alkalis and acids. It has the appearance of a blue powder, insoluble in most solvents including water.

Contents

History

The discovery of metal phthalocyanines can be traced to the observation of intensely colored byproducts from reactions of phthalic acid (benzene-1,2-dicarboxylic acid) or its derivatives with sources of nitrogen and metals. CuPc (copper phthalocyanine) was first prepared in 1927 by the reaction of copper(I) cyanide and o-dibromobenzene, which mainly produces colorless phthalonitrile as well as an intensely blue by-product. A couple of years later, workers at Scottish Dyes observed the formation of traces of phthalocyanine dyes in the synthesis of phthalimide by the reaction of phthalic anhydride and ammonia in the presence of metallic iron. In 1937, DuPont started producing copper phthalocyanine blue in the USA under the trade name Monastral Blue after it had been previously launched in Great Britain (ICI) and Germany (I.G. Farbenindustrie) in 1935. [1]

Difficulty was experienced in forming stable dispersions with the first alpha forms, especially in mixtures with rutile titanium, where the blue pigment tended to flocculate. The beta form was more stable, as was the improved stabilized alpha form. Today, there are even more isomeric forms available.

Synonyms and trade names

The substance, IUPAC name (29H,31H-phthalocyaninato(2−)-N29,N30,N31,N32)copper(II), is known by many names [2] such as monastral blue, phthalo blue, helio blue, [3] thalo blue, Winsor blue, [4] phthalocyanine blue, C.I. Pigment Blue 15:2, [5] [6] copper phthalocyanine blue, [7] copper tetrabenzoporphyrazine, [8] Cu-phthaloblue, [9] P.B.15.2, [10] [11] [12] C.I. 74160, [13] [14] [15] and British Rail Blue. [16] Numerous other trade names and synonyms exist. [17] The abbreviation "CuPc" is also used. [18]

Manufacture

Two manufacturing processes have gained commercial importance for the production of copper phthalocyanine:

Both approaches can be carried out either without (baking process) or with a solvent (solvent process). Higher yields may be achieved with the solvent process (> 95%) than with the baking process (70 to 80%), so that the solvent process has initially simulated more interest. However, recents trends show a reverse tendency for the baking process mainly on the grounds of economical and ecological concerns (solvent-free, shorter lead time).

Phthalonitrile process

This approach involves heating phthalonitrile with a copper salt, usually copper(I)chloride at 200°C to 240°C. The gross reaction equation from phthalonitrile may be written as follows:

Phthalic anhydride/urea process

The gross reaction equation from phthalic anhydride and urea may be written as follows:

Applications

AFM image of Fe and Co phthalocyanines Phthalocyanine AFM.jpg
AFM image of Fe and Co phthalocyanines

Catalysis

Metal phthalocyanines have long been examined as catalysts for redox reactions. Areas of interest are the oxygen reduction reaction and the sweetening of gas streams by removal of hydrogen sulfide.[ citation needed ]

Colorant

Due to its stability, phthalo blue is also used in inks, coatings, and many plastics. The pigment is insoluble and has no tendency to migrate in the material. It is a standard pigment used in printing ink and the packaging industry. Industrial production was of the order of 10,000 tonnes per annum in the 1980s and 1990s in Japan alone. [17] The pigment is the highest volume pigment produced. [19]

All major artists' pigment manufacturers produce variants of copper phthalocyanine, designated color index PB15 (blue) and color indexes PG7 and PG36 (green).

A common component on the artist's palette, phthalo blue is a cool blue with a bias towards green. It has intense tinting strength and easily overpowers the mix when combined with other colors. It is a transparent staining color and can be applied using glazing techniques.

It is present in a wide variety of products, [20] such as color deposition hair conditioner, [21] gel ink pens, eye patches, parfum, shampoo, skin-care products, soap, sunscreen, tattoo ink, [22] toothpaste, [23] and even turf colorants. [24]

Research

CuPc has often been investigated in the context of molecular electronics. It is potentially suited for organic solar cells because of its high chemical stability and uniform growth. [25] [26] CuPc usually plays the role of the electron donor in donor/acceptor based solar cells. One of the most common donor/acceptor architectures is CuPc/C60 (buckminsterfullerene) which rapidly became a model system for the study of small organic molecules. [27] [28] Photon to electron conversion efficiency in such system reaches approximately 5%.

CuPc has also been investigated as a component of organic field-effect transistors. [29] Copper Phthalocyanine (CuPc) has been suggested for data storage in quantum computing, due to the length of time its electrons can remain in superposition. [30] CuPc can be easily processed into a thin film for use in device fabrication, which makes it an attractive qubit candidate. [31]

Approximately 25% of all artificial organic pigments are phthalocyanine derivatives. [32] Copper phthalocyanine dyes are produced by introducing solubilizing groups, such as one or more sulfonic acid functions. These dyes find extensive use in various areas of textile dyeing (Direct dyes for cotton), for spin dyeing and in the paper industry. Direct blue 86 is the sodium salt of CuPc-sulfonic acid, whereas direct blue 199 is the quaternary ammonium salt of the CuPc-sulfonic acid. The quaternary ammonium salts of these sulfonic acids are used as solvent dyes because of their solubility in organic solvents, such as Solvent Blue 38 and Solvent Blue 48. The dye derived from cobalt phthalocyanine and an amine is Phthalogen Dye IBN. 1,3-Diiminoisoindolene, the intermediate formed during phthalocyanine manufacture, used in combination with a copper salt affords the dye GK 161.

Copper phthalocyanine is also used as a source material for manufacture of Phthalocyanine Green G.

Other related and commercially available phthalocyanines blue pigments are:

Structure, reactivity and properties

Portion of crystal structure of CuPc, highlighting its slipped-stack packing motif. CUPOCY15.png
Portion of crystal structure of CuPc, highlighting its slipped-stack packing motif.

Copper phthalocyanine is a complex of copper(II) with the conjugate base of phthalocyanine, i.e. Cu2+Pc2−. The description is analogous to that for copper porphyrins, which are also formally derived by double deprotonation of porphyrins. CuPc belongs to the D4h point group. It is paramagnetic with one unpaired electron per molecule.

The substance is practically insoluble in water (< 0.1 g/100 ml at 20 °C (68 °F)), [34] but soluble in concentrated sulfuric acid. [17] Density of the solid is ~1.6 g/cm3. [17] The color is due to a π–π* electronic transition, with λmax ≈ 610 nm. [35]

Crystalline phases

CuPc crystallizes in various forms (polymorphs). Five different polymorphs have been identified: [36] [37] [38] [39] phases α, β, η, γ and χ. The two most common structures in CuPc are the β phase and the metastable α phase. Those phases can be distinguished by the overlap of their neighboring molecules. The α phase has a larger overlap and thus, a smaller Cu-Cu spacing (~3.8 Å) compared to the β phase (~4.8 Å). [40]

Toxicity and hazards

The compound is non-biodegradable, but not toxic to fish or plants. [17] No specific dangers have been associated with this compound. [41] Oral LD50 in mammals is estimated to be greater than 5 g per kg, with no ill effects found at that level of ingestion, [17] for chronic ingestion estimated dose of low concern was 0.2 mg/kg per day in rats. [17] No evidence indicates carcinogenic effects. [17] Sulfonated phthalocyanine has been found to cause neuroanatomical defects in developing chicken embryos when injected directly into incubating eggs. [42]

See also

Related Research Articles

<span class="mw-page-title-main">Dye</span> Soluble chemical substance or natural material which can impart color to other materials

A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution and may require a mordant to improve the fastness of the dye on the fiber.

<span class="mw-page-title-main">Pigment</span> Colored material

A pigment is a powder used to add color or change visual appearance. Pigments are completely or nearly insoluble and chemically unreactive in water or another medium; in contrast, dyes are colored substances which are soluble or go into solution at some stage in their use. Dyes are often organic compounds whereas pigments are often inorganic. Pigments of prehistoric and historic value include ochre, charcoal, and lapis lazuli.

<span class="mw-page-title-main">Naphthalene</span> Chemical compound

Naphthalene is an organic compound with formula C
10
H
8
. It is the simplest polycyclic aromatic hydrocarbon, and is a white crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 ppm by mass. As an aromatic hydrocarbon, naphthalene's structure consists of a fused pair of benzene rings. It is the main ingredient of traditional mothballs.

<span class="mw-page-title-main">Porphyrin</span> Heterocyclic organic compound with four modified pyrrole subunits

Porphyrins are a group of heterocyclic macrocycle organic compounds, composed of four modified pyrrole subunits interconnected at their α carbon atoms via methine bridges (=CH−). In vertebrates, an essential member of the porphyrin group is heme, which is a component of hemoproteins, whose functions include carrying oxygen in the bloodstream. In plants, an essential porphyrin derivative is chlorophyll, which is involved in light harvesting and electron transfer in photosynthesis.

A substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and techniques are used. In practice, however, it is very difficult to achieve perfect dryness; anhydrous compounds gradually absorb water from the atmosphere so they must be stored carefully.

<span class="mw-page-title-main">Precipitation (chemistry)</span> Chemical process leading to the settling of an insoluble solid from a solution

In an aqueous solution, precipitation is the process of transforming a dissolved substance into an insoluble solid from a supersaturated solution. The solid formed is called the precipitate. In case of an inorganic chemical reaction leading to precipitation, the chemical reagent causing the solid to form is called the precipitant.

<span class="mw-page-title-main">Phthalic anhydride</span> Chemical compound

Phthalic anhydride is the organic compound with the formula C6H4(CO)2O. It is the anhydride of phthalic acid. Phthalic anhydride is a principal commercial form of phthalic acid. It was the first anhydride of a dicarboxylic acid to be used commercially. This white solid is an important industrial chemical, especially for the large-scale production of plasticizers for plastics. In 2000, the worldwide production volume was estimated to be about 3 million tonnes per year.

<span class="mw-page-title-main">Anthraquinone</span> Yellow chemical compound: building block of many dyes

Anthraquinone, also called anthracenedione or dioxoanthracene, is an aromatic organic compound with formula C
14
H
8
O
2
. Isomers include various quinone derivatives. The term anthraquinone however refers to the isomer, 9,10-anthraquinone wherein the keto groups are located on the central ring. It is a building block of many dyes and is used in bleaching pulp for papermaking. It is a yellow, highly crystalline solid, poorly soluble in water but soluble in hot organic solvents. It is almost completely insoluble in ethanol near room temperature but 2.25 g will dissolve in 100 g of boiling ethanol. It is found in nature as the rare mineral hoelite.

<span class="mw-page-title-main">Phthalocyanine</span> Chemical compound

Phthalocyanine is a large, aromatic, macrocyclic, organic compound with the formula (C8H4N2)4H2 and is of theoretical or specialized interest in chemical dyes and photoelectricity.

<span class="mw-page-title-main">Quinacridone</span> Organic compound used as a pigment

Quinacridone is an organic compound used as a pigment. Numerous derivatives constitute the quinacridone pigment family, which finds extensive use in industrial colorant applications such as robust outdoor paints, inkjet printer ink, tattoo inks, artists' watercolor paints, and color laser printer toner. As pigments, the quinacridones are insoluble. The development of this family of pigments supplanted the alizarin dyes.

<span class="mw-page-title-main">Thermochromism</span> Property of substances to change colour due to a change in temperature

Thermochromism is the property of substances to change color due to a change in temperature. A mood ring is an excellent example of this phenomenon, but thermochromism also has more practical uses, such as baby bottles which change to a different color when cool enough to drink, or kettles which change color when water is at or near boiling point. Thermochromism is one of several types of chromism.

<span class="mw-page-title-main">Diazonium compound</span> Group of organonitrogen compounds

Diazonium compounds or diazonium salts are a group of organic compounds sharing a common functional group [R−N+≡N]X where R can be any organic group, such as an alkyl or an aryl, and X is an inorganic or organic anion, such as a halide.

<span class="mw-page-title-main">Benzidine</span> Chemical compound

Benzidine (trivial name), also called 1,1'-biphenyl-4,4'-diamine (systematic name), is an organic compound with the formula (C6H4NH2)2. It is an aromatic amine. It is a component of a test for cyanide. Related derivatives are used in the production of dyes. Benzidine has been linked to bladder and pancreatic cancer.

<span class="mw-page-title-main">Quinoline Yellow SS</span> Chemical compound

Quinoline Yellow SS is a bright yellow dye with green shade. It is insoluble in water, but soluble in nonpolar organic solvents. Quinoline yellow is representative of a large class of quinophthalone pigments. It is suggested that quinoline yellow exhibits excited-state intramolecular proton transfer (ESIPT) behavior and the behavior might be the cause of its decent photostability, by recent spectroscopic study.

<span class="mw-page-title-main">Phthalocyanine Green G</span> Chemical compound

Phthalocyanine green G, which has many commercial names, is a synthetic green pigment from the group of phthalocyanine dyes, a complex of copper(II) with chlorinated phthalocyanine. It is a soft green powder, which is insoluble in water. It is a bright, high intensity colour used in oil and acrylic based artist's paints, and in other applications.

<span class="mw-page-title-main">Triflic acid</span> Chemical compound

Triflic acid, the short name for trifluoromethanesulfonic acid, TFMS, TFSA, HOTf or TfOH, is a sulfonic acid with the chemical formula CF3SO3H. It is one of the strongest known acids. Triflic acid is mainly used in research as a catalyst for esterification. It is a hygroscopic, colorless, slightly viscous liquid and is soluble in polar solvents.

<span class="mw-page-title-main">Alcian blue stain</span> Chemical compound

Alcian blue is any member of a family of polyvalent basic dyes, of which the Alcian blue 8G has been historically the most common and the most reliable member. It is used to stain acidic polysaccharides such as glycosaminoglycans in cartilages and other body structures, some types of mucopolysaccharides, sialylated glycocalyx of cells etc. For many of these targets it is one of the most widely used cationic dyes for both light and electron microscopy. Use of alcian blue has historically been a popular staining method in histology especially for light microscopy in paraffin embedded sections and in semithin resin sections. The tissue parts that specifically stain by this dye become blue to bluish-green after staining and are called "Alcianophilic". Alcian blue staining can be combined with H&E staining, PAS staining and van Gieson staining methods. Alcian blue can be used to quantitate acidic glycans both in microspectrophotometric quantitation in solution or for staining glycoproteins in polyacrylamide gels or on western blots. Biochemists had used it to assay acid polysaccharides in urine since the 1960s for diagnosis of diseases like mucopolysaccharidosis but from 1970's, partly due to lack of availability of Alcian and partly due to length and tediousness of the procedure, alternative methods had to be developed e.g. Dimethyl methylene blue method.

<span class="mw-page-title-main">Phthalonitrile</span> Chemical compound

Phthalonitrile is an organic compound with the formula C6H4(CN)2, which is an off-white crystal solid at room temperature. It is a derivative of benzene, containing two adjacent nitrile groups. The compound has low solubility in water but is soluble in common organic solvents. The compound is used as a precursor to phthalocyanine and other pigments, fluorescent brighteners, and photographic sensitizers.

<span class="mw-page-title-main">1,4-Dihydroxyanthraquinone</span> Chemical compound

1,4-Dihydroxyanthraquinone, also called quinizarin or Solvent Orange 86, is an organic compound derived from anthroquinone. Quinizarin is an orange or red-brown crystalline powder. It is formally derived from anthraquinone by replacement of two hydrogen atoms by hydroxyl (OH) groups. It is one of ten dihydroxyanthraquinone isomers and occurs in small amounts in the root of the madder plant, Rubia tinctorum.

In coordination chemistry, a macrocyclic ligand is a macrocyclic ring having at least nine atoms and three or more donor sites that serve as ligands. Crown ethers and porphyrins are prominent examples. Macrocyclic ligands often exhibit high affinity for metal ions, the macrocyclic effect.

References

  1. Löbbert, Gerd (2000). "Phthalocyanines". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a20_213. ISBN   978-3527306732..
  2. "Substance Information". ECHA. Retrieved 2021-11-18.
  3. Toxic Substances Control Act Chemical Substance Inventory: volume 2
  4. Spectroscopic Properties of Inorganic and Organometallic Compounds: volume 40
  5. Chem Product Index by Friedrich W. Derz
  6. Coloring of Plastics: Fundamentals, r. Robert A. Charvat
  7. Paint and Coating Testing Manual, e. Joseph V. Koleske
  8. User guide and indices to the initial inventory, substance name index, US EPA
  9. Industrial Organic Pigments: Production, Crystal Structures, Properties, Applications by Klaus Hunger & Martin U. Schmidt
  10. The Porphyrin Handbook: Applications of Phthalocyanines, e. Karl Kadish, Kevin M. Smith & Roger Guilard
  11. Tattoo Inks: Analysis, Pigments, Legislation by Gerald Prior
  12. Pigment + Füllstoff: Tabellen by Olaf Lückert
  13. Material Safety Data Sheets Service 7:89, Information Handling Services
  14. Coloring of Food, Drugs, and Cosmetics by Gisbert Otterstätter
  15. Chemical Formulation: An Overview of Surfactant Based Chemical Preparations Used in Everyday Life by Anthony E. Hargreaves
  16. Waterloo Station: A History of London's busiest terminus by Robert Lordan
  17. 1 2 3 4 5 6 7 8 COPPER PHTHALOCYANINE, CAS No.: 147-14-8 Archived 2017-05-16 at the Wayback Machine inchem.org
  18. e.g. Structural and Transport Properties of Copper Phthalocyanine (CuPc) Thin Films Archived 2012-03-05 at the Wayback Machine www.egmrs.org
  19. Gregory, Peter (2000). "Industrial applications of phthalocyanines". Journal of Porphyrins and Phthalocyanines. 4 (4). worldscinet.com: 432–437. doi:10.1002/(SICI)1099-1409(200006/07)4:4<432::AID-JPP254>3.0.CO;2-N.
  20. "Ci 74160 (With Product List)".
  21. "Color Deposition Conditioner "Ultra Violet"".
  22. Miranda, Michelle D. (2016) Forensic Analysis of Tattoos and Tattoo Inks. Routledge. ISBN   9780367778439 p. 163: Muddy Water Blue
  23. "Dentalux Complex 7 Total Care Plus Zahncreme Inhaltsstoffe – Hautschutzengel".
  24. "Vertmax Turf pigment and paint". 17 February 2022.
  25. Szybowicz, M (October 2004). "High temperature study of FT-IR and Raman scattering spectra of vacuum deposited CuPc thin films". Journal of Molecular Structure. 704 (1–3): 107–113. Bibcode:2004JMoSt.704..107S. doi:10.1016/j.molstruc.2004.01.053.
  26. Bala, M; Wojdyla, M; Rebarz, M; Szybowic, M; Drozdowski, M; Grodzicki, A; Piszczek, P (2009). "Influence of central metal atom in MPc (M = Cu, Zn, Mg, Co) on Raman, FT-IR, absorbance, reflectance, and photoluminescence spectra". J. Optoelectron. Adv. M. 11 (3): 264–269.
  27. Jailaubekov, Askat E.; Willard, Adam P.; Tritsch, John R.; Chan, Wai-Lun; Sai, Na; Gearba, Raluca; Kaake, Loren G.; Williams, Kenrick J.; Leung, Kevin; Rossky, Peter J.; Zhu, X-Y. (2013). "Hot charge-transfer excitons set the time limit for charge separation at donor/acceptor interfaces in organic photovoltaics". Nature Materials. 12 (1): 66–73. Bibcode:2013NatMa..12...66J. doi:10.1038/nmat3500. PMID   23223125.
  28. Xin, Li (January 2013). "CuPc/C60 bulk heterojunction photovoltaic cells with evidence of phase segregation". Organic Electronics. 14: 250–254. doi:10.1016/j.orgel.2012.10.041.
  29. Chaidogiannos, G.; Petraki, F.; Glezos, N.; Kennou, S.; Nešpůrek, S. (2009). "Low voltage operating OFETs based on solution-processed metal phthalocyanines". Applied Physics A. 96 (3): 763. Bibcode:2009ApPhA..96..763C. doi:10.1007/s00339-009-5268-1. S2CID   98694166.
  30. New material for quantum computing discovered out of the blue. phys.org. October 27, 2013
  31. Quenqua, Douglas (November 4, 2013). "A Key to Quantum Computing, Close to Home". The New York Times .
  32. Gerd Löbbert "Phthalocyanines" in Ullmann's Encyclopedia of Industrial Chemistry, 2002, Wiley-VCH, Weinheim. doi : 10.1002/14356007.a20_213.
  33. Erk, Peter; Hengelsberg, Heidi; Haddow, Mairi F.; Van Gelder, Richard (2004). "The innovative momentum of crystal engineering". CrystEngComm. 6 (78): 474. doi:10.1039/b409282a.
  34. Copper phthalocyanine chemblink.com
  35. Rzepa, H. S. Monastral: the colour of blue. .imperial.ac.uk Archived 2012-09-08 at archive.today )
  36. James H., Sharp; Martin, Abkowitz (1973). "Dimeric Structure of a Copper Phthalocyanine Polymorph". J. Phys. Chem. 77 (11): 477–481. doi:10.1021/j100623a012.
  37. Jacques M., Assour (1965). "On the Polymorphic Modifications of Phthalocyanines". J. Phys. Chem. 69 (7): 2295–2299. doi:10.1021/j100891a026.
  38. Hassan, A. K.; Gould, R. D. (2006). "Structural Studies of Thermally Evaporated Thin Films of Copper Phthalocyanine". Physica Status Solidi A. 132 (1): 91–101. Bibcode:1992PSSAR.132...91H. doi:10.1002/pssa.2211320110.
  39. Hai, Wang; Soumaya, Mauthoor; Salahud, Din; Jules A., Gardener; Rio, Chang; Marc, Warner; Gabriel, Aeppli; David W., McComb; Mary P., Ryan; Wei, Wu; Andrew J., Fisher; Marshall, Stoneham; Sandrine, Heutz (June 7, 2010). "Ultralong Copper Phthalocyanine Nanowires with New Crystal Structure and Broad Optical Absorption". ACS Nano. 4 (7): 3921–3926. arXiv: 1012.2141 . doi:10.1021/nn100782w. PMID   20527798. S2CID   2209898.
  40. Amy C, Cruickshank; Christian J, Dotzler; Salahud, Din; Sandrine, Heutz; Michael F, Toney; Mary P, Ryan (2012). "The crystalline structure of copper phthalocyanine films on ZnO(1100)". Journal of the American Chemical Society. 134 (35): 14302–14305. doi:10.1021/ja305760b. PMID   22897507.
  41. Safety data sheet Archived 2012-02-28 at the Wayback Machine cornelius.co.uk
  42. Sandor, S; Prelipceanu, O; Checiu, I (1985). "Sulphonated phthalocyanine induced caudal malformative syndrome in the chick embryo". Morphol Embryol (Bucur). 31 (3): 173–81. PMID   2931590.