Phosphate ester compositions for flame-retardant flexible PVC with high thermal stability

Abstract

The present invention relates to a compound represented by the general formula (I) (RO) m (PhO) 3-m The present invention relates to mixtures comprising at least two substances of formula P=O, where m=1, 2, or 3, R corresponds to the residue (A), and Ph corresponds to a phenyl group. The mixtures exhibit a unique combination of high thermal stability, high flame retardancy, and plasticizing effect, so that they are recommended for use as flame retardants in PVC compounds, as hydraulic fluids, as lubricant additives, or as additives for paints, adhesives, sealants, or coatings. JPEG2026507972000011.jpg18170

Description

[Background technology]

[0001] Phosphate esters can be used in a variety of technical applications, for example as plasticizers (see WO 02 / 04999), as flame retardants (see WO 02 / 04999), in lubricants (see WO 02 / 04999), or in hydraulic fluids (see WO 02 / 04999).

[0002] The flame retardant effect of phosphate esters has been demonstrated in various plastics, for example in PVC (see Patent Document 5), in polyolefins (see Patent Document 6), in cellulose esters (see Patent Document 7), in polyurethanes (see Patent Document 2), or in styrene polymers (see Patent Document 8), or in polycarbonate / acrylonitrile-butadiene-styrene (PC / ABS, see Patent Document 9).

[0003] The prior art describes various types of phosphoric acid esters and their use as flame retardants, for example, aryl esters of phosphoric acid, which are composed of phenol, cresol, tert-butylated phenol, isopropylated phenol, or mixtures thereof.

[0004] In addition to triaryl esters of phosphoric acid, mixed alkylaryl esters of phosphoric acid are also known to those skilled in the art. Patent Document 10 discloses that a mixture of diaryl alkyl phosphates and (monoalkylated) triaryl phosphates results in particularly thermally stable PVC compounds. This property is desirable in all applications of flexible PVC, since the production of such materials is carried out at high temperatures. Therefore, PVC molding compounds with high thermal stability are characterized by easier processability and better recyclability. However, the use of two different flame retardant formulations, as in Patent Document 10, exposes significant additional synthetic complexity.

[0005] Similarly, in U.S. Patent No. 5,629,239, a mixture of cyclic aryl phosphates and halogen-containing compounds is used to produce temperature-stable, flame-retardant PVC materials. However, the use of halogen-containing flame retardants is often problematic from a regulatory standpoint.

[0006] The triaryl phosphate ester compositions described in the prior art generally exhibit high flame retardancy in PVC. However, the flexible PVC materials produced therewith have low thermal stability. A further drawback of many triaryl phosphate ester compositions from the prior art is their triphenyl phosphate content. Their hazardous nature has led to a demand for even lower content of these substances for civilian use.

[0007] Complex formulations containing plasticizers, flame retardants, stabilizers, and possibly further additives for producing flexible PVC with improved thermal stability are also known to those skilled in the art. For example, Patent Document 12 describes the production of flame-retardant flexible PVC, using a mixture of trioctyl trimellitate (plasticizer), antimony trioxide (flame retardant), calcium-zinc stabilizer, and calcium carbonate (filler). However, the large number of additives required adds considerable technical complexity. In addition, antimony trioxide adversely affects the transparency of the PVC compound, which is undesirable in some demanding applications. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] German Patent No. 1 768 076 [Patent Document 2] U.S. Patent No. 8,129,457 B2 [Patent Document 3] U.S. Patent No. 10,414,964B2 [Patent Document 4] U.S. Patent No. 6,703,355 B2 [Patent Document 5] British Patent No. 2 302 543A [Patent Document 6] U.S. Patent No. 11,008,440B2 [Patent Document 7] U.S. Patent No. 9,000,148B2 [Patent Document 8] U.S. Patent No. 8,026,303 B2 [Patent Document 9] International Publication No. 2014171122A1 Brochure [Patent Document 10] U.S. Patent No. 5,087,521 [Patent Document 11] European Patent No. 0401366A4 [Patent Document 12] International Publication No. 2022 / 121330A1 Brochure

[0009] The object of the present invention was therefore to provide a flame retardant preparation which, in addition to a sufficient flame retardant effect, also has a plasticizing effect in plastics, in particular in PVC molding compounds, and in addition has high temperature stability. Preferably, this flame retardant should be in liquid form at room temperature and be producible by a simpler process and with a low triphenyl phosphate content. Summary of the Invention [Means for solving the problem]

[0010] The object of the present invention is to provide a compound represented by the general formula (I) (RO) m (PhO) 3-m P=O (I) wherein m=1, 2, or 3; and R is a group [ka] is equivalent to Ph corresponds to the phenyl group] This is achieved by a mixture comprising at least two substances:

[0011] In a preferred embodiment of the present invention, R in formula (I) is a group [ka] is equivalent to

[0012] In a further preferred embodiment of the present invention, the mixture herein comprises: (RO)3P=O, (RO)2(PhO)P=O, (RO)(PhO)2P=O, and (PhO)3P=O (triphenyl phosphate, "TPP"), and optionally secondary components such as guaiacol, phenol, catalyst components, or by-products.

[0013] The mixture according to the invention preferably contains at least 50% by weight, particularly preferably at least 70% by weight, very particularly preferably at least 80% by weight, most preferably at least 90% by weight of a compound of the general formula (I) (RO) m (PhO) 3-m P=O (I) wherein R, Ph, and m have the definitions given above. Contains substances such as:

[0014] In a preferred embodiment, the mixture according to the invention comprises: (i) 5% to 90% by weight of (RO)2(PhO)P=O, and (ii) 5 wt% to 90 wt% of (RO)(PhO)P=O wherein R and Ph have the definitions given above. Includes:

[0015] Further preferred embodiments include: (RO)3P=O: 0wt%~30wt% (RO)2(PhO)P=O: 5% to 90% by weight (RO)(PhO)2P=O: 5% to 90% by weight (PhO)3P=O (“TPP”): 0% to 30% by weight [in each case based on the total weight of compounds of formula (I) with m=0, 1, 2, or 3, preferably based on the total weight of the mixture, and R and Ph have the definitions given above] It is a mixture containing

[0016] The mixture according to the invention preferably contains less than 10% by weight, particularly preferably less than 5% by weight, even more preferably less than 1% by weight, very particularly preferably less than 0.5% by weight, most preferably not more than 0.2% by weight of triphenyl phosphate.

[0017] The mixtures according to the invention are preferably present as liquids at 23° C., since this facilitates or even enables their use as flame retardants or in lubricants or hydraulic fluids. The mixtures according to the invention preferably have a dynamic viscosity of 20 to 5000 mPa·s, particularly preferably 50 to 2000 mPa·s (in each case at 23° C.).

[0018] Preferably, the mixture according to the invention has an acid number of less than 5 mg KOH / g, preferably less than 1 mg KOH / g, particularly preferably less than 0.3 mg KOH / g, very particularly preferably less than 0.1 mg KOH / g.

[0019] Surprisingly, it has been found that PVC molding compounds containing the mixtures of the present invention have high temperature stability and high flame retardancy. Surprisingly, the mixtures of the present invention can be easily prepared by a novel process. A preferred embodiment of the process allows the mixtures to be prepared in such a way that they contain no or only very little triphenyl phosphate.

[0020] The present invention further provides a process for preparing the mixture of the present invention, comprising the steps of: a) providing a mixture comprising phosphorus oxychloride and guaiacol; b) reacting at least a portion of the mixture from a) at a temperature between 80°C and 300°C while removing hydrogen chloride; c) adding phenol to the mixture obtained from b) and further reacting it at 100°C to 300°C while releasing hydrogen chloride.

[0021] In an alternative embodiment, at least a portion of the phosphorus oxychloride is metered in only in step b). It is also possible to meter in at least a portion of the guaiacol only in step b).

[0022] In the reaction in step b) and / or c), a catalyst may be added. Examples of suitable catalysts are: NaCl, KCl, LiCl, MgCl, MgO, CaCl, AlCl, FeCl, ZnCl, TiCl, SbCl. The addition may be carried out during step a), b) or c), or between steps a) and b) or b) and c).

[0023] The reaction in step b) is carried out usually at a temperature in the range of 80 to 300°C, preferably in the range of 80 to 250°C, and particularly preferably in the range of 80 to 200°C.

[0024] Optionally, between step b) and step c), distillative removal of the (unreacted) reactants from step a) and / or the by-products formed can be carried out. The distillation can be carried out as a batch process or as a continuous process. The distillation temperature is preferably in the range of 80°C to 250°C. It is particularly preferred to carry out the distillation at the reaction temperature of step b) or at a temperature between 80°C and the reaction temperature of step b). The distillation is carried out at a pressure in the range of 0.01 mbar to 1013 mbar, preferably in the range of 0.01 mbar to 100 mbar, very particularly preferably in the range of 0.01 mbar to 50 mbar.

[0025] The reaction in step c) is usually carried out at a temperature in the range of 100 to 300°C, preferably in the range of 100 to 250°C, and particularly preferably in the range of 120 to 250°C.

[0026] In an alternative embodiment, at least a portion of the phenol is metered in only during the reaction in step c). It is also possible to meter in at least a portion of the reaction mixture obtained from step b) (either directly or after distillative removal of the reactants from step a) and / or by-products formed in step b) during the reaction in step c).

[0027] Optionally, distillative removal of (unreacted) reactants and / or by-products formed in step b) and / or step c) can be carried out after step c). The distillation can be carried out as a batch process or as a continuous process. The distillation temperature is preferably in the range of 80°C to 250°C. The distillation is carried out at a pressure in the range of 0.01 mbar to 1013 mbar, preferably in the range of 0.01 mbar to 100 mbar, very particularly preferably in the range of 0.01 mbar to 50 mbar.

[0028] According to application, the mixture of the present invention can also contain other auxiliaries.The examples of suitable auxiliaries are plasticizer, plasticizing polymer, polymer modifier, stabilizer (for example, heat stabilizer, light stabilizer, antioxidant), co-stabilizer (for example, acid scavenger, free radical scavenger), internal and external lubricant, viscosity adjuster, filler, color pigment, dye, flame retardant, flame retardant synergist, foaming agent, and further functional additives, such as antistatic agent, nucleating agent, UV protection agent or insecticide (see, for example, RD Maier, M.Schiller, Handbuch Kunststoff-Additive [Plastics Additives Handbook], 4th edition, Munich, Carl Hanser Verlag, 2016, p.513ff).

[0029] The mixture according to the invention is suitable as a flame retardant. Therefore, the invention further provides the use of the mixture according to the invention as a flame retardant.

[0030] The mixtures according to the invention can be used as flame retardants in all applications known to those skilled in the art. Preferably, the mixtures according to the invention are used as flame retardants for: - synthetic polymers such as polyolefins, polyvinyl chloride, polycarbonate, styrene-based (co)polymers, polyamides, polyesters, polyurethanes, elastomers such as NBR, CR, SBR or EPDM, and thermosetting resins such as epoxy resins, unsaturated polyester resins, and phenol formaldehyde resins. - materials of plant origin, such as wood, wood-plastic composites, paper and paperboard, and - Materials of animal origin, such as leather.

[0031] Particularly preferred is the use of the mixtures according to the invention as flame retardants for compositions containing polyvinyl chloride (PVC), such as PVC moulding compounds, i.e. PVC in the form of granules, powder, paste or plastisol.

[0032] Therefore, the present invention also provides compositions comprising the mixture of the present invention and polyvinyl chloride (PVC), preferably in the form of granules, powder, paste, or plastisol. These PVC molding compounds of the present invention are preferably flexible PVC. The PVC molding compounds of the present invention can be produced by mixing and compounding PVC with the mixture of the present invention and, optionally, further auxiliaries, such as stabilizers, in a known manner (see, for example, G. Becker, D. Braun, Kunststoff-Handbuch, Polyvinylchloride [Plastics Handbook, Polyvinyl Chloride], Vol. 2 / 2, Munich, Vienna, Carl Hanser Verlog, 1986, p. 829ff.), or by dispersing it to form a ready-to-use plastisol or organosol.

[0033] The PVC molding compound of the present invention contains preferably 5 to 150 parts by weight, particularly preferably 30 to 70 parts by weight, of the phosphate ester of formula (I) based on 100 parts by weight of PVC. In a preferred embodiment, the PVC molding compound of the present invention contains 5 to 150 parts by weight, particularly preferably 30 to 70 parts by weight, of the phosphate ester of formula (I) based on 100 parts by weight of PVC.

[0034] The PVC molding compounds of the present invention can be used in coatings, films, cables, pipelines, hoses, seals, conveyor belts, roofing membranes, adhesive tape films, tarpaulins, awnings, and tents.

[0035] The present invention further provides the use of the mixtures according to the invention in or for producing hydraulic fluids. The mixtures according to the invention are preferably used in fire-retardant hydraulic fluids.

[0036] The present invention further provides the use of the mixtures according to the invention as lubricant additives.The mixtures according to the invention are preferably used in fire-retardant lubricants.

[0037] The present invention further provides the use of the mixtures according to the invention as additives for paints, adhesives, sealants and coatings.

[0038] The present invention further provides the use of the mixture of the present invention as a heat transfer medium or in a preparation used as a heat transfer medium. Preferably, the mixture of the present invention is used as a heat transfer medium or in a heat transfer medium preparation for immersion cooling of electrical components. In addition to the mixture of the present invention, the heat transfer medium preparation further contains, for example, trialkyl phosphate, triaryl phosphate, mineral oil, polyalphaolefin, ester, antioxidant, metal deactivator, flow additive, corrosion inhibitor, antifoam agent, demulsifier, and / or pour point depressant. [Example]

[0039] Synthesis Example Synthesis Example 1 Phosphorus oxychloride (200 parts by weight), guaiacol (162 parts by weight), and magnesium chloride (0.1 parts by weight) were initially charged into a reactor equipped with a stirrer, internal thermometer, nitrogen inlet, and reflux condenser. The reaction mixture was heated with stirring to 100°C and maintained at this temperature until little or no gas evolution was observed. The pressure in the apparatus was gradually reduced from atmospheric pressure to 10 mbar and maintained under these conditions for 1 hour. After adding phenol (308 parts by weight), the reaction mixture was gradually increased to a final temperature of 140°C and maintained at this temperature until the conversion reaction was complete. Excess phenol was removed at a final temperature of 140°C and a pressure of 10 mbar. The reaction product mixture was isolated as a viscous liquid (180 mPa·s at 23°C). Its acid value was less than 0.1 mg KOH / g. The reaction product mixture contained the following: 0.4 wt% (guaiacylO)3P=O, 8.6 wt% (guaiacylO)2(PhO)P=O, 86.5 wt% (guaiacylO)(PhO)2P=O, and 4.5 wt% (PhO)3P=O ("TPP").

[0040] Synthesis Example 2 Phosphorus oxychloride (200 parts by weight), guaiacol (243 parts by weight), and magnesium chloride (0.1 parts by weight) were initially charged to a reactor equipped with a stirrer, internal thermometer, nitrogen inlet, and reflux condenser. The reaction mixture was gradually heated with stirring to 100°C and maintained at this temperature until little or no gas evolution was observed. After adding phenol (307 parts by weight), the reaction mixture temperature was gradually increased to a final temperature of 120°C and maintained at this temperature until the conversion reaction was complete. Excess phenol was removed at a final temperature of 160°C and a pressure of 10 mbar. The reaction product mixture was isolated as a viscous liquid (430 mPa·s at 23°C). Its acid value was less than 0.1 mg KOH / g. The reaction product mixture contained the following: 2.9 wt% (guaiacylO)3P=O, 45.8 wt% (guaiacylO)2(PhO)P=O, 47.8 wt% (guaiacylO)(PhO)2P=O, and 3.5 wt% (PhO)3P=O ("TPP").

[0041] Synthesis Example 3 Phosphorus oxychloride (200 parts by weight), guaiacol (324 parts by weight), and magnesium chloride (0.1 parts by weight) were initially charged to a reactor equipped with a stirrer, internal thermometer, nitrogen inlet, and reflux condenser. The reaction mixture was gradually heated with stirring to 120°C and maintained at this temperature until little or no gas evolution was observed. After adding phenol (185 parts by weight), the reaction mixture temperature was gradually increased to a final temperature of 140°C and maintained at this temperature until the conversion reaction was complete. Excess phenol was removed at a final temperature of 160°C and a pressure of 10 mbar. The reaction product mixture was isolated as a viscous liquid (1810 mPa·s at 23°C). Its acid value was 0.4 mg KOH / g. The reaction product mixture contained the following: 11.4 wt% (guaiacylO)3P=O, 81.5 wt% (guaiacylO)2(PhO)P=O, 6.9 wt% (guaiacylO)(PhO)2P=O, and 0.2 wt% (PhO)3P=O ("TPP").

[0042] Table 1 shows the amounts used in Synthesis Examples S1 to S3.

[0043] [Table 1]

[0044] Determination of the composition of phosphate ester compositions GC-FID quantitative analysis was performed using an Agilent 7890A GC system equipped with a CB-Sil 5 CB quartz capillary (length: 30 m, diameter: 0.32 mm, film thickness: 3.00 μm). The carrier gas used was hydrogen. The sample (dissolved in acetone) was injected in split mode (86:1) at a temperature of 300 °C. The following temperature program was set: starting temperature 60 °C, heating rate 10 °C / min to a temperature of 150 °C, then heating rate 25 °C / min to a temperature of 280 °C, holding time: 10 min, then heating rate 25 °C / min to a final temperature of 320 °C / min, holding time: 10 min. Evaluation was performed by integrating the signal separated from the corresponding baseline and converting the peak area to a pre-calibrated content.

[0045] Measurement of Viscosity of Phosphate Ester Compositions The dynamic viscosity of the phosphate esters was measured according to DIN 53018 using an Anton Paar MCR102 shear rheometer at a given temperature over a period of 200 s -1 The measurement was carried out at a shear rate of .

[0046] Measurement of acid value of phosphate ester composition The acid value of the sample was determined according to DIN EN ISO 2114 (Method B, colorimetric titration with phenolphthalein). For this purpose, 10 g of sample was weighed, dissolved in 200 mL of acetone and 50 mL of water, and mixed with 2-3 drops of phenolphthalein solution (0.1% by weight in ethanol / water (v / v = 4 / 1)). Sodium hydroxide solution (0.1 mol / L) was titrated from a burette with stirring until a color change from colorless to pink occurred (a duration of at least 10 seconds). A blank value was determined in the same way without the sample.

[0047] Comparative samples of known phosphate ester compositions Table 2 lists known phosphate ester compositions used as comparative samples for producing flexible PVC. Triguaiacyl phosphate was prepared according to WO 2014171122 A1. Other comparative samples are commercially available products from Lanxess Deutschland GmbH.

[0048] [Table 2]

[0049] Flexible PVC manufacturing The flexible PVC molding compounds used for the tests were made on a laboratory roll mill. After adding a mixture of all the ingredients (see Table 3), it was rolled to form a sheet. Once the sheet was formed, the compound was compounded on the roll mill for an additional 10 minutes and finally removed as a rolled sheet. The rolling temperature was 165°C.

[0050] Test specimens for measuring LOI were prepared from the rolled sheets using a press. The press temperature was 170°C. The press time was 4 minutes at low pressure (10 bar) for preheating and 2 minutes at high pressure (over 100 bar). Test specimens with dimensions of 90 x 13 x 4 mm were cut from the 4 mm thick pressed sheets.

[0051] The test specimens (50 × 40 × 6 mm) for measuring the hardness of the compounds were pressed for a longer time at the same temperature due to their thickness of 6 mm: 7 minutes for preheating at low pressure and 3 minutes for compression molding at high pressure.

[0052] Specimens for temperature stability testing were cut from thin (less than 1 mm) rolled sheets, which were removed from the roll mill after a 10 minute rolling period.

[0053] [Table 3]

[0054] PVC test specimens were prepared according to this procedure (Table 4).

[0055] Flame retardancy and plasticization effect measurement The limiting oxygen index (LOI) was used to assess flame retardancy. LOI is a measure of the burning behavior of plastics and other materials. It is the minimum oxygen concentration in a nitrogen / oxygen mixture that can cause combustion of a test specimen under standardized conditions. Tests were carried out in accordance with ISO 4589-2. For practical purposes, a value of at least 30 should be achieved in the test.

[0056] The plasticizing effect of phosphate esters was determined using Shore A hardness measurements on flexible PVC compounds containing phosphate esters. The measurement principle is based on the penetration depth of a metal test piece inserted into a material sample with a force of 12.5 N for 15 seconds. The Shore A hardness was measured on test specimens with dimensions of 50 x 40 x 6 mm. The Shore A hardness measurements were carried out in accordance with DIN ISO 7619-1. A Shore A hardness of less than 95 is considered an indication of a plasticizing effect.

[0057] The measurement results are summarized in Table 4.

[0058] [Table 4]

[0059] These results show that both the comparative products (Examples V1 to V5) and the mixtures S1, S2 and S3 according to the invention (Examples E6 to E8) provide good flame retardancy. The plasticizing effect (Shore A hardness) is lower than 95 in the comparative examples V1 to V4 and the inventive examples E6 to E8. In contrast, triguaiacyl phosphate (Example V5) known from WO 2014171122 A1 does not show a sufficient plasticizing effect. This compound is therefore unsuitable as a plasticizing flame retardant and was not further investigated.

[0060] Thermal stability measurements Thermal stability was determined using the Congo Red method in accordance with DIN EN ISO 182-1 3. For this purpose, material samples were heated in test tubes in a temperature-controlled oil bath to 180 °C. Under this thermal stress, PVC gradually decomposes, releasing hydrochloric acid. This process is strongly influenced by its formulation components, which accelerate or retard the release of hydrochloric acid. The hydrochloric acid evolved during this test was detected using a paper strip immersed in Congo Red solution and placed 3 cm above the PVC sample in the test tube. The time required for the color change from red to blue to occur was measured. The results are summarized in Table 5.

[0061] [Table 5]

[0062] The results show that the mixtures S1, S2 and S3 according to the invention (examples E6 to E8) have a higher thermal stability than the comparative examples (examples V1 to V4).

Claims

1. General formula (I) (RO) ｍ (PhO) ３－ｍ P=O (I) wherein m=1, 2, or 3; and R is a group 【Chemistry 1】 is equivalent to Ph corresponds to a phenyl group. A mixture containing at least two substances.

2. R is a group 【Chemistry 2】 2. The mixture of claim 1, wherein

3. (i) 5% to 90% by weight of (RO) ２ (PhO)P=O, and (ii) 5% to 90% by weight of (RO)(PhO) ２ P=O wherein R and Ph have the definitions given above.

3. The mixture of claim 1 or 2, comprising:

4. 4. The mixture according to claim 1, which contains less than 10% by weight, preferably less than 5% by weight, particularly preferably less than 1% by weight, very particularly preferably less than 0.5% by weight, and most preferably not more than 0.2% by weight of triphenyl phosphate.

5. 5. The mixture according to claim 1, which is present as a liquid at 23°C and 1013 mbar, preferably having a dynamic viscosity of 20 to 5000 mPa s, particularly preferably 50 to 2000 mPa s (in each case at 23°C).

6. (a) at least: phosphorus oxychloride, and - Guaiacol providing a mixture comprising: (b) reacting at least a portion of the mixture from a) at a temperature between 80°C and 300°C while removing hydrogen chloride; (c) adding phenol to the mixture obtained from b) and further reacting at between 100°C and 300°C while removing hydrogen chloride; A method for preparing the mixture of any one of claims 1 to 5, comprising:

7. 7. The process of claim 6, wherein distillative removal of reactants and / or by-products from step a) is carried out between step b) and step c).

8. 8. The method according to claim 6 or 7, wherein distillative removal of reactants and / or by-products from steps b) and / or c) is carried out after step c).

9. Use of a mixture according to any one of claims 1 to 5 as a flame retardant, preferably as a flame retardant for synthetic polymers, materials of plant origin or materials of animal origin, particularly preferably as a flame retardant for polyvinyl chloride (PVC).

10. A molding compound comprising the mixture according to any one of claims 1 to 5 and polyvinyl chloride (PVC).

11. 11. A moulding compound according to claim 10, comprising 5 to 150 parts by weight, preferably 30 to 70 parts by weight, of the phosphoric acid ester of formula (I), based on 100 parts by weight of PVC.

12. 12. Use of the composition according to claim 10 or 11 for producing coatings, films, cables, pipelines, hoses, seals, conveyor belts, roofing membranes, adhesive tape films, tarpaulins, awnings and tents.

13. Use of a mixture according to any one of claims 1 to 5 as a hydraulic fluid.

14. Use of the mixture according to any one of claims 1 to 5 as a lubricant additive.

15. 6. Use of a mixture according to any one of claims 1 to 5 as an additive for paints, adhesives, sealants or coatings.

16. Use of a mixture according to any one of claims 1 to 5 as a heat transfer medium.

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