DD227971A1 - SOLVENT-REDUCED CELLULOSENITRATE ALKYDE RESINS - Google Patents

Abstract

Low-solvent cellulose nitrate-alkyd resin paints based on a binder mixture of conventional cellulose nitrates and special novel alkyd resins which contain condensed hydroxyl- or carboxyl-functionalized oligomers of the α-methylstyrene. The application for industrial painting as well as in the field of craftsmen or do-it-yourselfers can be carried out as a clearcoat, primer, pre-coat and topcoat.

Description

Title of the invention

Solvent-reduced cellulose nitrate alkyd resin paints

Field of application of the invention

The invention relates to cellulose nitrate alkyd resin Anstriehstoffe which are characterized by lower solvent contents at processing viscosity.

Characteristic of the known technical solutions

The known cellulose nitrate alkyd resin paints contain substantially short oil alkyd resins, gellulose nitrates, plasticizers, pigments and organic solvents. The properties of the paint are determined by the types of the individual components and their proportions with each other. In order to set a customary for the spray-viscosity viscosity considerable amounts of organic solvents are required, which escape after application to the atmosphere and thus pose a burden on the environment _e When using medium or longer oil alkyd resins, which generally show a more favorable dilution behavior, is the possible Solvent saving nevertheless low, since an increased amount of cellulose nitrate must be used to bring the worse, mainly due to the plasticizing effect of these alkyd resins, properties of the coatings to a comparable level. To adjust the processing viscosity of these paints again an increased amount of solvent is necessary. (See Comparative Examples)

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Object of the invention

The object of the invention is to reduce the amount of solvent required for adjusting the processing viscosity of the cellulose nitrate-alkyd resin paints without impairing the properties of the paint film.

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Explanation of the essence of the invention

The object of the invention is to provide cellulose nitrate alkyd resin paints which have good properties of the coatings with low solvent requirement for processing.

This object is achieved in that the binder is a combination consisting of 30 to -50 parts by mass of cellulose nitrate and 70 to 20 parts by mass of at least one alkyd resin containing 20 to 50% by mass of a hydroxyl- or carboxyl-functionalized oligomer of the oC- The resulting paints may also contain minor amounts of soft or hard resins. "

Paints based on this binder show markedly reduced solvent consumption in adjusting the processing viscosity compared with known cellulose nitrate-alkyd resin paints without adversely affecting important properties such as drying, pendulum hardness, mechanical properties and gloss. The paints according to the invention even enable an increased hardness and an improved gloss of the coatings over the conventional paints based on cellulose nitrate-alkyd resin combinations.

Virtually all cellulose nitrates are suitable for the preparation of the binder combination. However, cellulose nitrates with an effective K value of 48 to 65 prove to be particularly favorable. They show good compatibility with the particular alkyd resins of the combination, are sufficiently fast in drying and in hardness formation and do not adversely affect gloss formation.

The alkyd resins suitable for the preparation of the binder combination are prepared by known methods. They contain in addition to the usual raw materials such as oils or fatty acids, di-, trihydric, tetrahydric or higher alcohols or mixtures thereof and polycarboxylic acids, especially dicarboxylic acids, in each Pall hydroxyl- or carboxyl-functionalized oligomers of oC-methylstyrene condensed. These oligomers have a molecular weight = 1000 g / mol, a functionality of 1 to 2, preferably 1.5 to 2 functional groups per molecule and can be up to 55% by mass, preferably in an amount of 20 to 50% by mass, in the alkyd resins are condensed.

These alkyd resins have an oil length of at most 50 %, preferably 20 to 35 % o Their viscosity is at a maximum 5000 mPa ^# s at a solids content of 75 to 95% by mass, the acid number is usually = 25 mg KOH / g, their Molecular weight is at most 2000 g / mol, preferably 1000 to 1600 g / mol

To prepare the binder combinations according to the invention, these alkyd resins may be used alone or mixtures thereof.

The cellulose nitrate-alkyd resin paints according to the invention can be processed as clear coats, but also pigmented, according to the particular formulation as a primer, precoat or topcoat. They are prepared by known methods. The processing of the paints according to the invention can be carried out in practice by all known processes. Particularly favorable, the advantageous properties can be used in spray application.

embodiments

All of the following examples, including comparative examples, were adjusted by varying the ratio of alkyd resin to cellulose nitrate to give virtually identical readings in terms of their coating characteristics.

The paints were applied by spraying on a glass and sheet with a viscosity of 50 ί 1 sec flow time according to TGL 14301/01 so that a dry film thickness of 30 micrometers was obtained. The adjustment of the processing viscosity was carried out with a solvent mixture of butanol, butyl acetate, xylene in the ratio 1: 2: 2. The ratio of pigment to binder was kept constant in all examples. For the preparation of the paints according to the invention and of the comparative paints based on known alkyd resins, alkyd resins were used whose composition is given in Table 1.

Table 2 shows the characteristics of the alkyd resins thus obtained.

Table 3 lists the characteristics of the oligomers of OC-methylstyrene used.

The comparison of the differently composed, inventive and known Gellulosenitrat-alkyd resin combinations is carried out in Table 4 and the respective test values of the coatings obtained therefrom in Table 5.

Table 1

Composition in parts by weight

raw materials A B C 5 alkyd resin e 4 τπ / ** ι JC \ J 27.0 8th . 8.2 - 4 D _ • mm ' - Penta erythritol 13 11.4 - 1 _ - 3 - - 1,3 butylene glycol - - 25 4 6.9 - ) - - Trimethylol propane - 8th 21 (2) 20.6 29 3 39.6 Phthalic anhydride 44.3 39.1 19 - 17.2 «C-methylstyrene oligomer 27.0 33.7 32 _ 27.0 51 41.0 43.0 fatty acid (D (2) 30.2 (1 (3) (3) - - (D 19 24.2 glycerol - - - - hexanetriol -

(1) Rizine fatty acid

(2) tall oil fatty acid

(3) ricinoleic acid

COO. ^ & O tJ

Table 2

A characteristics C the alkyd resins F G characteristic value 23.8 B. 22.6 Alkyd resin D E 33.0 18.0 Acid number ing KOH / g 80.1 25.6 80.4 25.1 25.0 74.6 70.2 Plague % 3710 79.8 2600 79.9 75.1 4700 620 Viscosity in butyl acetate mPa · s 1930 2910 1600

Table 3

characteristics A Alkyd resin B C D Functionalization carboxyl carboxyl hydroxyl carboxyl functionality 1.6 1.9 1.9 2.0 Molina s se 590 640 670 690

Table 4

Γ raw material Composition of the embodiments example 2 3 4 5 in parts by weight , 2 3 Alkyd resin 80 % ± g 29.5 21.1 .26,9 13.1 Comparative example Alkyd resin 75 % ± S 1 _ mm 1 26.2 mm Alkyd resin 70 % ± g 28.1 mm mm _ 10 Alkyd resin type B C D C 24.3 G Cellulose nitrate E 510 _ T 12.2 _ Cellulose nitrate E 560 A 10.2 20 e 14.1 20 Cellulose nitrate E 480 11.25 16.8 15.3 Plasticizer (dibutyl phthalate) 2.3 3.0 2.3 4.0 2.6 4.0 TiO ₂ -R 15 15 15 15 15 15 Hard Resin (Cyclohexanone or Maize Resin) 2.3 2.8 4 15. 15 -

The parts by mass of cellulose nitrates are understood to be free of solvents or wetting agents.

Table 5

Check fourth 1 2 example 4 5 Comparative Example 2 3 62.5 61.3 3 63.0 72.2 I ¹ 69.5 76 Solvent content at processing viscosity 25 27 63.5 22 70 I 68.0 25 60 Dry degree 4 to TGL 14301/03 (min) 40 35 20 38 100 24 • 30 100 Pendulum hardness after 24 h after TGL 29771 (see) 8.7 8.5 45 8.1 6.1 27 8.0  5.9 Erichsen recess according to TGL 14302/03 (mm) 1 1 7.8 1 1 '7,8 1 1 Grid cut characteristic according to TGL 14302/05 <3 1 1 Mandrel bending test according to TGL 14302/02 (mm) · 80- 85 <3. 83 77 <3 80 76 Gloss according to TGL 107-06104.1 78 80

Claims (1)

Srfindungsanspruch Solvent-reduced cellulose nitrate-alkyd resin paints based on a mixture of cellulose nitrates, alkyd resins, solvents and optionally pigments, fillers, dyes, minor amounts of soft or hard resins, plasticizers, moisturizers and other paint auxiliaries, characterized in that the binder mixture comprises 30 to 50% by weight of Parts cellulose nitrate and 70 to 20 parts by mass of at least one alkyd resin, which contains up to 50% by mass of hydroxyl- or carboxyl-functionalized oligomers of oC-methylstyrene condensed consists.