·Home ·Table of Contents ·Conservation and Restoration in Art and Architecture

Microbiological testing of Polymers and resins used in conservation of Linen Textiles Omar Abdel-Kareem Microbiology Dept., Cracow Univ. of Economics, ul. Sienkiewicza 5, 30-033 Krakow, Poland Permanent address: Conservation Dept., Faculty of Archaeology, Cairo Univ., Egypt. Contact

Abstract

In this study Egyptian linen textiles were treated by 12 different polymers and resins, which are important in conservation of ancient Egyptian linen textiles. Untreated and treated samples were deteriorated by 7 selected fungal strains isolated from ancient Egyptian textiles, for two weeks. Tensile strength of the biodeteriorated samples was assessed. SEM was used to fallow the change in the surface morphology of the biodeteriorated samples. Also, Spectrophotometric measurements were used to assess change in colour differences of the biodeteriorated samples. The results obtained had showed that most of tested polymers reduce the biodeterioration of linen textiles but not prevent the deterioration at all. Beva 371, Plexisol P-550, Paraloid B72 and starch carbamate are the most tested polymers resistant for biodeterioration. Acryloid F-10, Calaton CA and Mowilith are the least tested polymers resistant for biodeterioration.

Introduction

Resins and polymers are commonly used in textile conservation (Keyserlingk, 1990, Landi, 1998, Timar-Balazy and Eastop, 1998 and Abdel-Kareem, 1999). Textile conservators may encounter polymers and resins either as part of the ^"original object" or as a later added material, or as materials conservators wish to add (Abdel-Kareem, 2000). Santoro and Koestler, 1991, confirmed that selection of a polymer based only on non-biological criteria may initially succeed in minimising physical and chemical deterioration of the substrate, but in the longer term may lead to enhanced biological degradation and a worse deterioration condition than that before treatment. It is necessary to understand the potential of a polymer to act play as a food source for microbes, before an intelligent choice of an appropriate polymer is made for a given application. Resins of both natural and synthetic origin may be destroyed by biological agents, and therefore can also stimulate the growth of microorganisms on textiles. Additives are used in order to give resins certain characteristics (such as plasticisers) can in fact be a source of nutrition for some biological agents (Gillatt, 1990). Choice of resin for conservation of a particular object must be made after considering properties required for the material in situ (Horie, 1995).

This study tends to evaluate the most suitable and effective polymers and resins that can be applied safely and successfully in treating ancient Egyptian linen textiles. This paper is drawn from a larger research project. More detailed descriptions of testing procedures and an indeapth discussion of the results can be found in Abdel-Kareem^,s thesis.

Materials and methods

Polymers and Resins:
Selected polymers and resins are currently used in conservation of archaeological textiles, or materials that could be used in the future for the same purpose (See Table 1), (Abdel-kareem, 2000).

	Chemical Name	Trade Name	Producer	Conc %
1	Vinyl acetate/acrylic ester copolymer	Mowilith DM5 (E)	Hoechst	10
2	Vinyl acetate/dibutyle maleate copolymer	Mowilith DMC2 (E)	Hoechst	10
3	Ethyl acrylate/ methyl methylacrylate	Paraloid B72 (SD)	Rohm and Hass]	6
4	Butyl acrylate/ methyl methylacrylate	Lascaux 360 HV (E)	Lascaux Restauro	10
5	Ethyl acrylate/ methyl methylacrylate	Plextol B-500 (E)	Lascaux Restauro	10
6	Butyl methylacrylate	Acryloid F-10 (SN)	Rhom and Haas	10
7	Butyl methylacrylate	Plexisol P-550 (SN)	Lascaux Restauro	10
8	Soluble nylon	Calaton CA (SD)	Imperial Chemical Industrials ICI	6
9	Keton resin N	Beva 371 (SN)	Lascaux Restauro	10
10	Methyl hydroxy ethyl cellulose	Tylose MH300 (SD)	Hoechst	4
11	Hydroxypropylcellulose	Klucel G (SD)	Lascaux Restauro	4
12	Starch carbamate	(SD)	prepared according to (Sayed, et al 1988)	6
Table 1: Polymers and resins used in this study

(E) = Emulsion; (SD) = Solid; (SN) = Solution

Fabrics:
Unbleached Egyptian linen fabric was used in this work and its specifications (See Table 2).

Structure	Colour	Brightness (L)	Nominal Wt.	Thread/cm.		Liner density (Tex.)		% of elongation	Tensile strength
Plain weave	Grey		g/m.	warp	weft	warp	weft	30.57	29.08
1/1		50.24	260	20	16	20	20		Newton
Table 2: Specifications of used linen

Preparation of samples:
The fabric was first washed in sterilised distilled water and dried at ambient temperature. The linen fabric samples were cut into 12 x 2 cm (length x width) warp test specimens. The warp strips were produced by ravelling away yarns on each side forming 1.5cm wide strips with a 2.5mm fringe down each side. These samples were used for tensile strength and elongation test. 5 samples were used for each fungus. Other linen fabric samples were cut into 5 x 5 cm (length x width) specimens to be used for Spectrophotometric measurements and S.E.M. 5 samples were used for each fungus. The samples were soaked in polymer preparations, which were previously prepared according to Abdel-kareem, 2000, and dried at ambient temperature.

Fungal strains:
7 selected active fungal strains isolated from ancient Egyptian linen textiles were used (Abdel-Kareem, et al, 1997). These selected fungal strains are

1. Alternaria tenuissima,
2. Aspergillus nidulans,
3. Aspergillus terreus,
4. Chaetomium globosum,
5. Penicillium asperum,
6. Penicillium funiculosum and
7. Trichoderma viride.
These fungal strains were selected based on the obtained results of previous studies (Abdel-Kareem, Szostak-Kotowa, 1998, Abdel-Kareem, 2000).

Treatment of linen with fungi:
Unconsolidated and consolidated samples were treated with these selected fungal strains by using Agar Plate Test with application of pure strains method (Abdel-Kareem, 2000).

Methods of measurement of biodeterioration

Spectrophotometric measurements:
Reflection spectra was recorded for both the front side and behind side samples in the visible range (360-800nm) by a Shimadzu Double Beam UV-2101PC Spectrophotometer Equiped with ISR48 Intergating Sphere, with using barium sulphate as a reference (a white standard). In order to determine the relative rate of colour changes of the bio-deteriorated samples the reflectance values were inserted into a computer program which then calculated the CIELAB colour coordinates for L, a, and b values. Calculation of total colour change (D E) is achieved by the use of the following equations: D E = [(D L)² + (D a)² + (D b)²]^0.5 (Abdel-Kareem, 2000).

SEM studies:
A JSM-400 Scanning Electron Microscope was used to record the changes of surface morphology of consolidated and unconsolidated (control) after fungal treatment.

Tensile strength and elongation:
Tensile strength and elongation of samples were measured by using a testing machine, type Zwick 1445. These tests were done according to the standard PN-88/P-04626. The initial distance of jaws was 50 mm and the testing speed was 25 mm / min, temperature was 23^o C, and R.H.65%. The average value of five readings for each test was taken.

Results and discussion

Tensile strength:
Tensile strength of unconsolidated (control) and consolidated linen textile samples before and after treated by fungi are shown (Table 3), as well as, loss of strength of consolidated linen textile samples before and after treated by fungi (Table 4). The data show noticeable decreases in tensile strength among all consolidated samples after fungal deterioration. The results show that percentage of loss of tensile strength of samples treated with most tested polymers, exceeds 70%. It means that the majority of tested polymers are susceptible to fungal deterioration. The data also show that the majority of tested polymers reduce loss of tensile strength of linen textiles treated with these polymers after fungal deterioration. The results prove that % loss of tensile strength of most of the samples treated with tested polymers is lower than % loss of tensile strength of unconsolidated samples (control) after fungal deterioration. It means that the majority of tested polymers retard fungal deterioration of linen but does not prevent it. Or in other wards we can say that the majority of tested polymers improve resistance of linen textiles against fungal deterioration. These results also indicate that the ability of tested polymers to improve the linen against fungal deterioration depends on both the type of polymer and fungal species. However, the results show that there is no polymer retard all tested fungal strains. The results prove that linen samples consolidated by Plexisol P-550, Starch carbamate, and Beva 371 present the lowest loss in tensile strength after deterioration by most of the tested fungal strains, while linen samples consolidated by Mowilith, Calaton CA, Plextol B-500 and Acryloid F-10 present the biggest loss in tensile strength after deterioration by most of the tested fungal strains. These results reveal that Plexisol P-550, Starch carbamate and Beva 371 are the most effective polymers retarding fungal deterioration of linen textiles among tested polymers, while Mowilith, Calaton CA, Plextol B-500 and Acryloid F-10 are the least effective ones.

Polymer	Fungi
	-	1	2	3	4	5	6	7
Unconsolidated	29.08	0.41	0.79	0.16	0.36	0.24	3.12	3.13
Mowilith	28.90	3.27	2.87	1.86	0.32	1.50	1.44	2.73
Paraloid B72	28.03	2.65	4.52	0.55	0.95	2.01	1.04	2.92
Lascaux 360 HV	25.78	9.43	2.89	0.94	0.53	2.17	1.04	2.37
Plextol B-500	29.86	4.80	2.60	0.77	1.07	1.04	1.47	0.70
Acryloid F-10	25.75	0.77	3.45	1.43	0.54	2.21	1.50	1.42
Plexisol P-550	27.63	17.98	12.77	1.96	4.97	15.70	7.18	3.31
Calaton CA	33.55	3.16	1.49	0.83	0.23	1.71	0.69	0.24
Beva 371	29.64	12.46	12.19	0.91	0.54	10.06	7.26	2.50
Tylose MH300	30.15	17.93	27.75	2.36	1.30	3.34	5.45	4.86
Klucel G	28.81	11.60	8.37	3.03	1.03	3.03	2.31	2.54
Starch carbamate	27.00	14.83	8.25	2.84	2.02	9.56	13.02	8.30
Table 3: Tensile strength of linen samples consolidated by polymers and damaged by tested fungi

Polymer	Fungi
	-	1	2	3	4	5	6	7
Unconsolidated	0	98,59	97,28	99,45	98,76	99,18	89,27	89,24
Mowilith	0,62	88,76	90,13	93,60	98,90	94,84	95,05	90,61
Paraloid B72	3,61	90,89	84,46	98,11	96,73	93,09	96,42	89,96
Lascaux 360 HV	11,35	67,57	90,06	98,32	98,18	92,54	96,42	91,85
Plextol B-500	-2,68	83,49	91,06	97,35	96,32	96,42	94,94	97,59
Acryloid F-10	11,45	97,35	88,14	95,08	98,14	92,40	94,84	95,12
Plexisol P-550	4,99	38,17	56,09	93,26	82,91	46,01	75,31	88,62
Calaton CA	-15,37	89,13	94,88	97,15	99,21	94,12	97,63	99,18
Beva 371	-1,93	57,15	58,08	96,87	98,14	65,41	75,03	91,40
Tylose MH300	-3,68	38,34	4,57	91,88	95,53	88,51	81,26	83,29
Klucel G	0,93	60,11	71,22	89,58	96,46	89,58	92,06	91,27
Starch carbamate	7,15	49,00	71,63	90,23	93,05	67,13	55,23	71,46
Table 4: Loss % of tensile strength of linen samples consolidated by polymers and damaged by tested fungi

Total colour difference (D E):
Values of total colour change (D E) of consolidated and unconsolidated linen samples before and after deterioration by fungi are shown in (Table 5). The results show that there are noticeable changes in all consolidated samples after the fungal deterioration. As it was confirmed by Abdel-Kareem, 1998 that fungal deterioration causes changes in the colour of linen. It indicates that all tested polymers are susceptible to fungal deterioration. But the results also showed that the degree of changes in the colour of samples consolidated by most tested polymers, is lower than changes of unconsolidated samples after fungal deterioration. It confirms that the majority of tested polymers cause reduction in fungal deterioration of linen. This reduction depends on both the type of the polymer and the fungal strain. The colour change (D E) show that no polymer reduces fungal deterioration of linen among all tested polymers. For examples, Starch Carbamate and Plexisol P-550 cause reduction in deterioration of linen by all tested fungal species except Trichoderma viride. Paraloid B72 causes reduction in fungal deterioration of linen by Aspergillus terreus, Alternaria tenuissima, and Penicillium funiculosum, while the same polymer does not cause any reduction in fungal deterioration of linen by Trichoderma viride, Aspergillus nidulans, Chaetomium globosum, and Penicillium asperum. The results also show that colour change of some consolidated samples deteriorated by Trichoderma viride are more than unconsolidated samples deteriorated by the same fungus. It means that some of the tested polymers cause acceleration in fungal deterioration of linen by Trichoderma viride. It also confirms that Trichoderma viride is the most active on linen samples consolidated with most of tested polymers among tested fungi.

Polymer	side	Fungi
		-	1	2	3	4	5	6	7
Unconsolidated	Back	-	21,56	21,01	29,32	27.97	30,42	7,53	19,38
	Front	-	15,34	25,63	28,27	36.17	41,58	8,25	13,68
Mowilith	Back	3.85	7.36	1.12	8.05	30.89	6.72	0.65	7.09
	Front	3.85	12.30	4.41	1.19	33.26	1.12	3.80	0.59
Paraloid B72	Back	6.88	5.69	2.60	1.98	2.73	11.19	17.76	5.44
	Front	6.88	18.92	1.48	12.76	1.31	11.34	21.29	2.18
Lascaux 360 HV	Back	7.17	3.97	7.94	1.27	3.09	9.42	20.22	6.35
	Front	7.17	2.94	10.88	5.04	6.55	3.63	30.83	1.54
Plextol B-500	Back	0.93	0.37	9.98	1.02	0.83	8.72	8.62	18.09
	Front	0.93	7.63	2.13	1.22	4.04	2.91	0.24	-8.02
Acryloid F-10	Back	5.92	17.96	9.68	0.02	11.40	25.56	6.19	3.33
	Front	5.92	14.64	1.32	3.04	15.16	13.21	0.90	1.74
Plexisol P-550	Back	4.53	2.30	7.00	4.16	5.96	3.60	21.40	5.21
	Front	4.53	5.31	0.73	3.49	2.33	8.03	12.25	1.64
Calaton CA	Back	0.39	5.38	5.25	1.21	12.40	3.87	11.86	0.95
	Front	0.39	16.36	6.13	9.47	10.01	9.14	10.89	5.30
Beva 371	Back	0.17	10.50	3.14	9.54	6.94	3.00	27.94	7.03
	Front	0.17	1.69	9.31	4.07	0.30	4.52	15.68	0.64
Tylose MH300	Back	4.08	3.28	0.05	1.81	5.13	17.57	3.26	4.32
	Front	4.08	3.31	5.55	1.98	1.23	3.60	12.30	9.76
Klucel G	Back	2.97	1.50	3.41	7.94	2.65	0.03	5.42	4.87
	Front	2.97	5.64	5.03	9,47	5.13	5.04	1.19	2.13
Starch carbamate	Back	5.41	1.14	6.64	7.89	3.11	6.02	21.94	5.45
	Front	5.41	8.44	1.38	3.31	1.32	0.90	24.34	3.42
Table 5: Colour difference (D E) of linen consolidated by polymers and damaged by tested fungi

SEM Studies:
Results of study the surface morphology of biodeteriorated sampleswere recorded by SEM. They show that all consolidated samples after fungal deterioration showed considerable damages of surface. It means that all the tested polymers are susceptible to fungal deterioration. The results show that the damage of the surface of the biodeteriorated unconsolidated samples (control samples), are more than the damage of the majority of biodeteriorated consolidated samples. It confirms that the majority of tested polymers reduced fungal deterioration of linen. The results show that the degree of reduction in damage of the surface morphology depends on both the type of the polymer and the fungal species. Since it is not possible to present here all SEM photographs, I have chosen the most important ones. Photofigure (1) show the most and the least effective polymers in preservation of tested samples. It is clear that Beva 371, Plexisol P-550, and starch carbamate caused little reduction in fungal deterioration of linen samples in the majority of tested fungi. It is clear that the fungal deterioration of linen samples treated with Calaton CA, Mowilith DM5, and Acryloid F10 is similar to or exceeds fungal deterioration of the unconsolidated samples. It means that Calaton CA, Mowilith DM5, and Acryloid F10 do not cause any retardation in fungal deterioration of linen.

SEM photographs of fungal growth on biodeteriorated surface of unconsolidated samples and consolidated after damaged by tested fungi. A) Control sample (2000X), B,C,D,E,F,G,H) unconsolidated samples after deterioration with B) Aspergillus nidulans (1000X), C) Aspergillus terreus (1000X), D) Penicillium asperum (2000X), E) Alternaria tenuissima (2000X), F) Chaetomium globosum (200X), G) Trichoderma viride (1000X), H) Penicillium funiculosum (1000X). Samples consolidated with Beva 371 after damaged, I) Aspergillus nidulans (2000X), J) Penicillium asperum (2000X), K) Trichoderma viride (2000X). Samples consolidated with Plexisol P-550 after damaged by, L) Aspergillus terreus (2000X), M) Aspergillus nidulans (2000X), N) Trichoderma viride (2000X). Samples consolidated with starch carbamate after damaged by O) Penicillium asperum (2000X), P) Chaetomium globosum (2000X), Q) Penicillium funiculosum (2000X). Samples consolidated with Calaton CA after deterioration with Aspergillus nidulans (2000X). Samples consolidated with Acryloid F10 after deterioration with Alternaria tenuissima (2000X). Samples consolidated with Mowilith DM5 after deterioration with Aspergillus terreus (2000X).

Inclusive Discussion:
A variety of methods were applied in this study to measure fungal deterioration of consolidated linen textiles. In the field of conservation, a combination of factors such as: change of colour, change of tensile strength, change of surface morphology are of importance to the conservators more than growth the organism on the substrate. Thus the conservator may not care whether an organism resides on the surface of a coating as long as it does not effect on the properties of the object such as: discoloration of the object or a loss in strength of the object. Therefore when we evaluate the ability of the polymer to promote or inhibit fungal deterioration of linen textiles, we should have all properties of linen in mind. The obtained results of the study revealed that most of tested polymers retard fungal deterioration of linen textiles. It may stem from a variety of reasons. Polymers increase the degree of polymerisation of cellulose fibers as these polymers bond between the cellulose chains. The highest degrees of polymerisation of the materials increase resistance of these materials against fungal deterioration. Polymers cover linen textile surface with a thin coating film. This coat film acts as a barrier between the fungi and the linen textiles. In order to the fungi to biodegrade textiles, they have to be in touch with the textile fibers. Therefore only the fungi which able to secrete enzymes able to hydrolysis this coat film will be able to biodegrade the linen textile. However, biodeterioration of polymer depends on both the chemical composition of the polymer and the degree of the polymerisation or length of the polymer chain. Some of tested polymers may also have fungicide components in the composition of the polymer that plays a role in increasing the resistance of the polymer against fungal deterioration.

In accordance with the total measurement results, those polymers or resins that showed the most overall retard to the fungal deterioration of linen were Paraloid B72, Beva 371 and starch carbamate. These results in agreement with previous studies on biodeterioration of resins used in conservation field. Sayed, et al, (1988) showed that Starch carbamate, is one of the most resistant to biological attack. (Koestler and Santoro 1988) confirmed that Paraloid B72 is a moderate resistant for biological attack. The total measurement results indicate that those polymers or resins which showed the least overall retardation to the fungal deterioration of linen were acryloid F-10 and Mowilith. These results in agreement with previous studies on biodeterioration of resins used in conservation field, which showed that Acryloid F-10, was one of the least resistant to biological attack (Kowalik 1980, Koestler and Santoro 1988). This study offers evaluation of the most suitable and effective resins or polymers that can be applied safely and successfully in treating ancient Egyptian linen textiles. The present study does not refer to all requirements should be met but only to the role of these polymers in the fungal deterioration. According to Egyptian archaeological rules (Abdel-Hamid, 1989), polymer or resin used in conservation of archaeological textiles should not accelerate the fungal deterioration on these textiles. The results of the present study show that most of tested polymers or resins do not accelerate but retard fungal deterioration by most of the tested fungi. The results also show that all tested polymers or resins susceptible to fungal deterioration. It means that most of tested polymers can be used in conservation of linen textiles as consolidants but not to protect them against fungal deterioration.

Conclusion

1. Linen textiles consolidated by all tested polymers are susceptible to fungal deterioration.
2. However most of tested polymers cause little retardation in fungal deterioration of linen textiles.
3. Beva 371, Plexisol P-550, and starch carbamate are the most frequent cause of retardation in fungal deterioration of linen among tested polymers.
4. Acryloid F-10 and Mowilith are the least resistant to fungal attack among tested polymers.
5. The study reveals that the polymers or resins (Acryloid F-10 and Mowilith) that showed poor resistance to fungal deterioration are extensively used in conservation of archaeological textiles. For this reason the study recommends to inform the textile conservators to be made aware of the potential biodeterioration problems connected these polymers. The object conserved with these polymers should be displayed or stored in controlled environment, which may reduce their susceptibility to fungal attack. Attempts should be done to replace these polymers with more resistant ones or to combine them with a fungicide.
6. The present study is the first attempt to evaluate the role of conserved polymers in the fungal deterioration of Ancient Egyptian linen textiles. Other measuring methods may be useful to cast more light on the changes in the polymers and resins after fungal deterioration, e.g. measurement of chemical changes by using different techniques.

References

1. Abdel-Hamid, H.M., (1989): Standards and Rules, Which Regulate Monuments Conservation Methods, Faculty of Archaeology Journal, No.3, Cairo University.
2. Abdel-Kareem, O.M.A., (1999): An Evaluation of the Use of Resins in Ancient Egyptian Textiles Conservation: Part 2: Effect of Ageing on Mechanical and Physical Properties of Linen Textile Consolidated with Resins, Czasopismo Techniczne 1A/1999 (Rok 96), Wydawnictwo Politechniki Krakowskiej, Kraków, Poland, pp.195-207.
3. Abdel-Kareem, O.M.A., (2000), Microbiological Studies to Evaluate Polymers and Resins Used in Consolidation of Ancient Egyptian Linen Textiles, Czasopismo Techniczne, 1A/2000 (Rok 96), Wydawnictwo Politechniki Krakowskiej, Kraków, Poland, pp.202-211.
4. Abdel-Kareem, O.M.A., (2000), Application of Fungicides and Polymers in Preservation of Linen Textiles, Ph.D. Thesis, Microbiology Dept., Economic University, Cracow, Poland.
5. Abdel-Kareem, O.M.A., Szostak-Kotowa, J., Barabasz, w., Pasmionka, I., and Galus, A., (1997): Fungal Biodeterioration of Ancient Egyptian Textiles, Part I: Survaying Study for The Most Dominant Fungi on Ancient Egyptian Textiles, IN: Drobnousreoje W Srodowisku Wystepowanie, Aktywnosc i Znaczenie, Wyd. AR Kraków, PP.279-290.
6. Abdel-Kareem, O.M.A., Szostak-Kotowa, J., (1998): Effect of Fungi on the surface morphology of Ancient Egyptian Linen Textiles, 4th International Conference on Biodeterioration of Culture Property, 21-25 November 1998. Tehran, Iran.
7. Abdel-Kareem, O.M.A., Szostak-Kotowa, J., (1998): Spectrophotometric Studies of the Effict Fungi on Egyptian Linen Textiles, 4th International Conference on Biodeterioration of Culture Property, 21-25 November1998. Tehran, Iran.
8. Gillatt, J., (1990): The Biodeterioration of Polymers Emulsions and its Prevention with Biocides, International Biodeterioration, No.26, pp.205-216.
9. Horie, C.V., (1995): Resins; Useful but A Problem? In: Resins Ancient and Modern, Preprints of the SSCR,S 2nd Resins Conference Held at the Department of Zoology, University of Aberdeen, 13-14 September, Edinburgh, pp.1-3.
10. Keyserlingk, M.A., (1990): The Use of Adhesives in Textile Conservation, Preprints of the 9th Triennial Meeting of the ICOM Committee for Conservation, Dresden, Germany, pp.307-312.
11. Koestler R.J., and Santoro, E.D., (1988): Assessment of the Susceptibility to Biodeterioration of Selected Polymers and Resins, GCI Scientific Program Report, Final Report Submitted to the Getty Conservation Institute, USA.
12. Kowalik, R., (1980): Microbiodeterioration of Library Materials, Part 2, Restaurator, Vol.4.
13. Landi, S., (1998): The Textile Conservator's Manual, London.
14. PN-88/P-04626. Tekstylia. Wyznaczanie sily zrywajacej I wydluzenia metoda paskowa.
15. Santoro, E.D., and Koestler, R.J., (1991): A Methodology for Biodeterioration Testing of Polymers and Resins, International Biodeterioration 28, pp. 81-90.
16. Sayed, F.A., Tera, F.M., Refaai, R.A., and El-Alfy, E.A., (1988): Improving The Rot-resistance of Cellulosic Fabrics by Using Synthesized Soluble Starch Compounds Part 1: Starch Carbamate, The First Arab Conference on Biophysics 28-30 Nov. 1988,Cairo Univ., pp.403-408.
17. Timar-Balazsy, A., and Eastop, D., (1998): Chemical Principles of Textile Conservation, Butterworth.

© AIPnD , created by NDT.net

|Home|    |Top|