Effect of Weave Parameters on Air Resistance of Fabric Made From Doubled Yarns and With Different Weave Structures

Abstract

The effect weave parameters such as CFF (crossing over firmness factor), FYF (floating yarn factor), FFF (fabric firmness factor) and fabric geometrical properties, namely, areal density, thickness and porosity on air resistance, is examined. A series of woven fabrics differing only in weave structures and having the common count and fabric sett was produced from three types of doubled yarns, namely, compact/compact, conventional/conventional and compact/conventional. The hybrid combination was produced principally to reduce the cost of manufacturing doubled yarns. Essential data for the fabrics such as CFF, FYF, FFF, mass per unit area, thickness and porosity were determined. Air resistance was determined by performing the standard test KES-F8 API. Analysis of the results with respect to fabrics produced from the compact/compact, conventional/conventional and conventional/compact yarns shows a strong correlation between the air resistance, porosity, CFF, FYF, FFF, mass per unit area and thickness (R = conventional/conventional 0.97, compact/compact 0.861, conventional/compact 0.974). Thus, in addition to the CFF, FYF and FFF, the thickness should also be taken into consideration for predicting the air resistance of fabrics. It is concluded that in order to predict air resistance, a number of parameters are needed and any conclusion which has been drawn using only CFF and FYF should be treated with caution.

Introduction

Doubling is a value addition process which enhances strength and uniformity. The textile and apparel industries have benefitted from the use of doubled yarn in introducing innovative and technical textiles. The advent of new types of yarns such as compact yarns makes it imperative to study the potential of doubling these yarns with a view to using them to the maximum extent. Designers of fabric products also look to benefit from the doubling of compact yarns.

An interesting study carried out by Marie Havlová ¹ on air permeability has shown that pore size and shape, texture arrangements, and so on are very important to have a better understanding. A relationship for predicting fabric air permeability was proposed. It was shown that on the basis of values for linear density of the yarns and the diameter of one interyarn pore, it was possible to predict appropriate permeability values. A detailed analysis of the fabric structure revealed that if the fabric structure is not quite regular, the use of the characteristic dimension of one ‘average pore’ may not be sufficient for the prediction of air permeability. Also, it was pointed out that average pore size is not decisive but the actual size of individual pores is important.

Onder et al. ² studied the mechanical properties and air permeability of high weight wool blend apparel fabrics. The mechanical responses in uniaxial tensile and tear tests of grey state fabrics and low deformation characteristics were reported by them. The use of siro spun yarn led to a slight drop in shear rigidity and higher air permeability of fabrics. The subject of air permeability has attracted the attention of many research workers. These studies have addressed the relationship between air permeability and the structural properties of fabrics, namely, mass per unit area, fabric thickness, porosity, type of yarn and finishes but without weave parameters. Generally, it has been found that as fabric mass and thickness increase, air permeability decreases. Subramaniam et al. ³ have studied the air permeability of blended nonwoven fabrics. They stressed the importance of porosity in making predictions for nonwoven fabrics. The prediction of air permeability by a model was done by Saldaeva ⁴ of Nottingham University, making use of a commercial finite element package. A computational fluid dynamics (CFD) model using CFX 10 was developed for predicting air permeability. Fatahi and Yazdi ⁵ were the first research workers to correlate weave parameters to air permeability. They predicted air permeability from weave structure by multiple regression equations.

Prediction of air permeability by neural networks has been carried out by Tokarska. ⁶ Recently, Afzal et al. ⁷ carried out an extensive study on air permeability of polyester cotton blended interlock knitted fabrics. They found that fabric thickness and areal density significantly affected air permeability. Fatahi and Yazdi, ⁵ using the parameters CFF (crossing over firmness factor) and FYF (floating yarn factor), predicted the air permeability of woven fabrics. They did not calculate the FFF (fabric firmness factor) as they felt that the equations given by Milasius were quite complicated. Their model should be treated with caution as other parameters such as thickness, area of density and porosity also affect air permeability.

The role of porosity on air permeability was also investigated by Cheng and Cheung ⁸ and Kane et al. ⁹ who found that weft knitted fabrics made from compact yarns possessed higher air permeability in comparison to those produced from conventional yarns. Xiao et al. ¹⁰ studied the importance of compression on through thickness permeability in technical textiles. They also studied the effect of low air pressure compression on through thickness through permeability. The effect of air pressure drop on thickness was investigated. Fabric through thickness permeability was shown to be highly related to thickness. Air permeability has been predicted by porosity measurement. Hydraulic conductivity and diameter of pores, the number of macro pores and the total porosity of woven fabrics were considered. Rombaldoni et al. ¹¹ dealt with the effect of carbon dioxide dry cleaning on the air permeability of men’s suiting.

Zhu et al. ¹² studied the air permeability and thermal resistance of textiles under heat convection. A newly developed device was developed for evaluating the thermal resistance of textiles. It has been shown that with the increase in the pore size and the ratio of pore area to the total area of fabric, the air permeability increases and thermal resistance decreases. Pore size and the ratio of pore area have a significant effect compared with the porosity value. A paper by Angelova et al. ¹³ discusses the computational modelling and experimental value of the air permeability of woven structures on the basis of simulation of jet systems. The flow through the interstices between the warp and weft threads is modelled as an ‘in-corridor’–ordered jet system, formed by nine jets issuing from nine pores of the woven structure. A good correlation between the experimental values and the simulated values was noted for five factors which were manufactured.

The air permeability of multi-layer cotton fabrics, as affected by structure and yarn colour, has been studied by Urbas et al. ¹⁴ It has been demonstrated that by suitable choice of construction and yarn colours, it is possible to have good air permeability and UV protection. The effect of relative humidity on air permeability has been studied by Wehner et al. ¹⁵ It was found that the fabric structure, number of bonding points, yarn twist and yarn crossover points affected the air permeability of woven and nonwoven fabrics.

Xiao et al. ¹⁶ stressed the importance of the dynamic air permeability of woven fabrics. Dynamic air permeability can be determined when a porous medium is tested under transient pressure conditions. A reliable approach to measuring and characterizing dynamic air permeability was developed. Backer ¹⁷ was the pioneer who emphasized the role of interstices on the air permeability of fabrics. He calculated minimum horizontal pore areas and then related them to the air permeability of fabrics. Backer’s work remains as a precursor to air permeability studies of fabrics. A number of papers discuss the air permeability of knitted fabrics, which underlines the importance of fabric mass, thickness and porosity. ¹⁸ A novel approach for measuring the air permeability of air bags by shock waves which are reflected by the fabric structure is discussed by Wang et al. ¹⁹

In this article, a study on the effect of weave parameters, such as CFF, FYF and FFF and fabric geometrical properties, namely, areal density, thickness and porosity, on air resistance is reported. Earlier work by Fatahi and Yazdi ⁵ on air permeability was conducted only considering CFF and FYF, and the FFF was not computed in view of its complexity. The FFF is important in various industries, particularly in textiles and apparel, because it plays a significant role in determining the performance, comfort, and durability of the fabric. The present work includes this parameter (FFF) and relates it to air resistance of woven fabrics for the first time, and reports the results.

Materials and Methods

60S Ne conventional and compact ring spun yarns were produced from the same mixing. Table 1 gives the properties of single and doubled yarns. Using the above two yarns, three types of doubled yarns of 19.08tex conventional/conventional, 19.49tex compact/compact, and 19.35tex conventional/compact were produced. The reason for producing the hybrid yarn, namely conventional/compact, was to reduce the cost of doubled yarn as the cost of compact yarn is twice as much as that of conventional yarn. The twist multiplier for each combination was kept the same and the doubling machine setting was also kept constant.

Table 1.

Single and doubled yarn properties.

	Single yarn		Doubled yarns
Parameters	60 s compact	60 s conventional	CC	RR	RC
Count (tex)	9.74	9.54	19.49	19.08	19.35
Twist per cm	12.71	13.36	9.23	9.27	9.22
TM	4.16	4.16	4.20	4.22	4.25
U%	11.13	11.75	7.88	9.92	8.15
THIN -50%	8	20	0.00	0.00	0.00
THICK +50%	65	80	2.5	17.5	7.5
NEPS + 200%	145	215	7.5	62.5	15.0
HAIRINESS	3.11	4.95	3.90	5.42	4.70
CV % (HAIRINESS)	5.99	5.00	7.88	6.9	6.1
STRENGTH (cN)	175.50	146.90	394.4	318.9	359.3
CV % (STRENGTH)	9.20	10.50	7.5	6.9	6.1
ELONGATION %	4.07	4.02	4.93	4.37	4.32
CV % (ELONGATION)	9.10	10.75	7.4	7.3	8.9
RKM	18.35	15.67	21.17	17.11	18.83

CC: Compact/Compact, RR: Conventional/Conventional, RC: Conventional/Compact.

Fabric Production

Eleven fabric samples, which were identical in the warp and weft sett but differing in the weave structure for analysing the fabric sett or other properties, were woven on an automatic loom. Weave structures include plain, 2/2 twill, 4/4 twill, 2/2 pointed twill, 8 thread twilled hopsack, 8 thread weft sateen, 8 thread honey comb, 8 thread Brighton honey comb, 8 thread Huck-a-back, 8 thread crepe cord and 8 thread pin head crepe. They are given in Figure 1. While the plain weave has more interlacements of warp and weft yarns, the 2/2 weave has ridges on the fabric surface and the 8 thread weft sateen has weft floats. The crepe weave is a derivative of the plain weave.

Figure 1.

Weave structures with weave factors

Fabric Processing

These fabrics were subsequently bleached with hydrogen peroxide with an M:L ratio of 1:10, a hydrogen peroxide concentration of 1.5%, caustic soda 1.2%, wetting agent 0.5%, lubricant oil 0.3% and stabilizer (sodium silicate) 0.2%, at 90°C for 45 min.

Test Methods

Porosity

All the tests were carried out at 65 ±2% RH, and 25 ± 2°C in bleached fabrics only. The porosity of the cotton fabric was determined using the following equation:

$$\mathrm{Porosity}(\%)=1-\frac{{\rho }_{\mathrm{fab}}}{{\rho }_{\mathrm{fib}}}$$

where ρ_fab is the fabric bulk density and ρ_fib the fibre density of cotton which is 1.55 g/cc. ²⁰ The bulk density of the fabric was calculated using the following equation:

$$\mathrm{Fabric}\mathrm{bulk}\mathrm{density}(\mathrm{g}/{\mathrm{cm}}^3)=\frac{\mathrm{GSM}/10000}{\mathrm{Thickness}\mathrm{of}\mathrm{fabric}\mathrm{in}\mathrm{cm}}.$$

Thickness, GSM and Air Resistance

The thickness was measured on a thickness tester using ASTM D1777 standards. GSM (grammes per square metre) was measured using ASTM D3776 standards. Air resistance was measured using a KES – F8 API air permeability tester (Kato Tech Co. Ltd, Japan), which has a constant rate of air flow with different pressure measurement methods. Testing was performed according to the ASTM D737 standards. The mean of five readings was taken for each fabric in a bleached state.

Parameters of Weave Structures

Crossing-over Firmness Factor

The crossing-over firmness factor (CFF) is defined as:

$$\mathrm{CFF}=\frac{\mathrm{Number}\mathrm{of}\mathrm{cros}\sin \mathrm{g}\mathrm{over}\mathrm{lines}\mathrm{in}\mathrm{the}\mathrm{complete}\mathrm{repeat}}{\mathrm{Number}\mathrm{of}\mathrm{int}\mathrm{erlacement}\mathrm{po}\mathrm{int}\mathrm{in}\mathrm{the}\mathrm{complete}\mathrm{repeat}}$$

Ogawa ²¹ originally coined this term. However, it was not clearly understood for further investigation. In order to clarify the term, Morino et al. ²² redefined the CFF, as:

$$\mathrm{CFF}={\mathrm{N}}_{\mathrm{c}}/{\mathrm{N}}_{\mathrm{i}}$$

where N_c is the number of crossing-over lines in the complete repeat and N_i is the number of interlacing points in the complete repeat

The details of the CFF for a plain weave structure are shown in Figure 2. The crossing-over line number is counted as 1 when the interlacing point changes, for example, the warp yarn changes from over to under the weft yarn, or vice versa in the warp direction. The number is summed up in the complete repeat. In the case of plain weave, there are eight crossing over lines in the complete repeat and four interlacing points. Hence, CFF becomes 2.

Figure 2.

Details of CFF.

FYF

The FYF is defined as follows:

$$\mathrm{FYF}=\frac{({\mathrm{Type}}_{\mathrm{I}~\mathrm{IX}}-1)\times (\mathrm{Existing}\mathrm{number}\mathrm{of}{\mathrm{type}}_{\mathrm{I}~\mathrm{IX}}\mathrm{in}\mathrm{the}\mathrm{complete}\mathrm{repeat})}{\mathrm{Number}\mathrm{of}\mathrm{int}\mathrm{erlacing}\mathrm{po}\mathrm{int}\mathrm{s}\mathrm{in}\mathrm{the}\mathrm{complete}\mathrm{repeat}}$$

FYF evaluates the length of parts of floats. Details of the floating yarn are given in Figure 3.

Figure 3.

Floating of yarn.

FFF

The FFF was calculated using the following formula computed by Milašius:^23,24

$$\varphi =\sqrt{\frac{12}{\pi }}\frac{1}{P_1}\sqrt{\frac{T_{\mathrm{av}}}{\rho }}{S}_2\frac{1}{1+\frac{2}{3}\sqrt{\frac{T_1}{T_2}}}{S}_1\frac{\frac{2}{3}\sqrt{\frac{T_1}{T_2}}}{1+\frac{2}{3}\sqrt{\frac{T_1}{T_2}}}$$

where $\mathrm{\rho }=\frac{{\mathrm{S}}_1{\mathrm{\rho }}_1+{\mathrm{S}}_2{\mathrm{\rho }}_2}{{\mathrm{S}}_1+{\mathrm{S}}_2}$ ; ${\mathrm{T}}_{\mathrm{av}}=\frac{{\mathrm{S}}_1{\mathrm{T}}_1+{\mathrm{S}}_2{\mathrm{T}}_2}{{\mathrm{S}}_1+{\mathrm{S}}_2}$ .

T ₁, T₂ and T_av are, respectively, the warp count, weft count and average count in Tex. P₁ is the Milašius^23,24 weave factor and ρ is the fiber density. S₁ and S₂ are the ends and picks per decimeter.

The weave Factor

The weave factor (P) represents the number of interlacements of warp and weft which are obtained from the weave matrix. The FYF proposed by Morino et al. ²² can be taken as a measure of floats in the fabric. It has a high correlation with weave factor. Since the calculation of weave factor is quite complicated, it was calculated using software [http://www.textiles.ktu.lt/Pagr/En/Cont/pagrE.htm]. ²⁵

Results and Discussion

The fabric geometrical properties and weave structures are given in Table 2. The fabrics have been divided into four groups according to their CFF and FFF values. Each group is characterized by a particular effect such as no floats, short floats, bigger floats and biggest floats. Group 1 fabrics have high CFF 2.00 and FFF 0.49, group 2 fabrics have CFF 1.5 and FFF 0.44, group 3 fabrics have CFF 1–1.25 and FFF 0.37–0.40 and group 4 fabrics have CFF 0.5 and FFF 0.27–0.29.

Table 2.

Fabric particulars for conventional/conventional, compact/compact and conventional/compact yarns.

		Areal density(g/cm2) off loom	Areal density(g/cm2) afterbleaching	Thicknesscm	Porosity%	CFF	FYF	FFF	Air resistance kPa s/m	Ends/cm	Picks/cm	Ends/cm	Picks/cm
	Conventional/Conventional											Off loom
G1	Plain	106.32	97.58	0.034	80.639	2	0	0.59	0.177	22	23	20	19
G2	8 Thread BrightonHoney Comb	113.41	102.8	0.057	87.977	1.5	0.5	0.53	0.06	22	23	20	19
	8 Thread Crepe cord	107.82	96.84	0.057	88.674	1.5	0.5	0.52	0.05	23	23	20	20
G3	2/2 Twill	109.42	98.64	0.042	84.192	1	1	0.5	0.077	23	25	20	21
	2/2 Pointed Twill	106.33	94.72	0.044	85.648	0.969	1.031	0.46	0.05	23	23	20	20
	8 Thread Twilled Hopsack	102.47	93.68	0.045	86.244	1	1	0.6	0.04	23	24	19	21
	8 Thread Pin head crepe	100.89	91.78	0.053	88.368	1.125	0.875	0.47	0.047	22	22	20	20
	8 Thread honey Comb	110.21	98.02	0.046	85.917	1.188	0.812	0.43	0.047	23	20	20	20
	8 Thread Huck–a–Back	107.39	96.26	0.053	87.983	1.25	0.75	0.47	0.04	22	22	19	19
G4	4/4 Twill	100.32	91.34	0.048	87.207	0.5	1.5	0.33	0.047	23	24	20	21
	8 Thread Weft Sateen	100.82	91.24	0.047	87.167	0.5	1.5	0.32	0.03	22	22	20	20
	Compact/Compact
G1	Plain	105.49	96.94	0.034	80.766	2	0	0.59	0.073	22	23	20	19
G2	8 Thread BrightonHoney Comb	107.33	98.86	0.059	88.753	1.5	0.5	0.53	0.03	22	23	20	19
	8 Thread Crepe cord	109.21	102.24	0.058	88.329	1.5	0.5	0.52	0.04	23	23	20	20
G3	2/2 Twill	100.87	91.40	0.044	86.024	1	1	0.5	0.05	23	25	20	21
	2/2 Pointed Twill	107.43	97.56	0.047	86.278	0.969	1.031	0.46	0.05	23	23	20	20
	8 Thread Twilled Hopsack	100.81	92.04	0.047	87.055	1	1	0.6	0.027	23	24	19	21
	8 Thread Pin head crepe	101.32	94.16	0.048	87.030	1.125	0.875	0.47	0.02	22	22	20	20
	8 Thread honey Comb	109.62	101.86	0.048	85.970	1.188	0.812	0.43	0.03	23	20	20	20
	8 Thread Huck–a–Back	107.84	96.46	0.055	88.222	1.25	0.75	0.47	0.033	22	22	19	19
G4	4/4 Twill	100.55	91.32	0.047	86.936	0.5	1.5	0.33	0.03	23	24	20	21
	8 Thread Weft Sateen	105.49	97.52	0.051	87.252	0.5	1.5	0.32	0.02	22	22	20	20
	Conventional/Compact
G1	Plain	104.90	95.10	0.032	80.432	2	0	0.59	0.087	22	23	20	19
G2	8 Thread BrightonHoney Comb	110.31	103.62	0.056	87.664	1.5	0.5	0.53	0.023	23	23	20	19
	8 Thread Crepe cord	109.91	103.60	0.058	88.009	1.5	0.5	0.52	0.04	23	25	20	20
G3	2/2 Twill	105.59	95.92	0.043	84.989	1	1	0.5	0.057	23	25	20	21
	2/2 Pointed Twill	102.71	94.90	0.047	86.539	0.969	1.031	0.46	0.04	23	23	20	20
	8 Thread Twilled Hopsack	100.27	93.16	0.044	86.012	1	1	0.6	0.04	23	24	19	21
	8 Thread Pin head crepe	102.33	94.56	0.050	87.392	1.125	0.875	0.47	0.03	23	23	20	20
	8 Thread honey Comb	109.19	98.68	0.046	85.822	1.188	0.812	0.43	0.03	23	20	20	20
	8 Thread Huck–a–Back	106.49	93.78	0.051	87.837	1.25	0.75	0.47	0.02	22	22	19	19
G4	4/4 Twill	100.89	91.76	0.048	87.256	0.5	1.5	0.33	0.033	23	24	20	21
	8 Thread Weft Sateen	101.33	92.18	0.047	86.925	0.5	1.5	0.32	0.023	22	22	20	20

It is evident that lower CFF and FFF are associated with lower values of air resistance. Table 3 gives the correlation coefficients between weave parameters and air resistance and fabric geometrical properties and air resistance. That there exists a significant correlation between CFF and air resistance can be noticed. Also, the correlation between FFF and air resistance is highly significant and the correlation between fabric thickness and air resistance is also good and significant.

Table 3.

Correlation between weave parameters with air resistance.

Weave parameters	Conventional/conventional	Compact/compact	Conventional/compact
CFF	0.702 a	0.613 a	0.569
FYF	–0.703 a	–0.616 a	–0.571
FFF	0.640 a	0.655 a	0.583
Weave factor (P1)	–0.494	–0.524	–0.443
Thickness (cm)	–0.678 a	–0.726 a	–0.719 a
GSM	0.335	–0.328	0.014
Porosity (%)	–0.863 b	–0.827 b	–0.884 b

a

Correlation is significant at the 0.05 level (two-tailed).

b

Correlation is significant at the 0.01 level (two-tailed).

Effect of CFF on Air Resistance

Figure 4 illustrates the relationship between the CFF and air resistance. It is apparent that as the CFF increases, the air resistance increases due to the absence of floats and more interlacements. This is in agreement with the findings of Fatahi and Yazdi. ⁵ The correlation between the CFF and air resistance is 0.702, which is significant. This shows that the fabric becomes harder with a large CFF.

Figure 4.

Relationship between air resistance and CFF.

Effect of FYF on Air Resistance

The trend in air resistance as affected by FYF is depicted in Figure 5. It is the mirror image of CFF. This is also in substantial agreement with the findings of Fatahi and Yazdi. ⁵ The FYF represents the number of floats and is positively correlated with the weave factor P1. The reduction in air resistance with an increase in FYF is due to the presence of floats.

Figure 5.

Relationship between air resistance and FYF.

Effect of FFF on Air Resistance

Figure 6 illustrates the relationship between FFF and air resistance from which it is apparent that as the FFF increases the air resistance increases, a trend noticed between CFF and air resistance. It may be noted that this relationship is reported for the first time as determination of this parameter was found to be complicated as pointed out by Fatahi and Yazdi. ⁵ Padaki et al. ²⁶ also did not compute the FFF in their studies.

Figure 6.

Relationship between air resistance and FFF.

Effect of Thickness and Air Resistance

Figure 7 shows the relationship between thickness and air resistance. This is in substantial agreement with findings of Afzal et al. ⁷

Figure 7.

Relationship between air resistance and thickness.

Effect of Porosity on Air Resistance

The relationship between porosity and air resistance is found to be good. Figure 8 illustrates the trend of porosity and air resistance.

Figure 8.

Relationship between air resistance and porosity.

Interrelationship Between Other Parameters

It is also interesting to note the significantly higher correlation between FFF and CFF as shown Figure 9.

Figure 9.

Relationship between CFF and FFF.

Another interesting observation is the highly significant correlation between CFF and FFF which shows that both parameters give the same answer. This is in substantial agreement with the findings of Sankaran and Subramaniam. ²⁷ Since the correlation between CFF and air resistance is greater than that with the thickness, the prediction of air resistance can also be made well using CFF. The correlation between porosity and air resistance is good. With the exception of plain weave, in all other cases the values of air resistance are low. This shows that floats in the fabrics cause a reduction in air resistance. The bigger the value of FYF, the longer the floats and vice versa. Since the correlation between CFFF and FFF is positive and is highly significant, both can be considered for grouping the samples. Thus air resistance can be predicted from the CFF, FYF and FFF in view of their higher correlation with the air resistance. Correlation between FYF and weave factor is found to be high and significant (r = 0.919).

Statistical Analysis

Minitab 18 software was used to analyse the significance of the data and the interaction between the variables using the general linear model (multiple factor analysis of variance (ANOVA)) at the 95% confidence level. The effect of porosity, CFF, FYF, FFF, air resistance and conventional/conventional, compact/compact, conventional/compact yarn and the interactions between them were analysed for the fabrics. The p-values were inspected to analyse the significance of the effects. The results are presented in Table 4. The statistical analysis reveals that the values are significant for all the factors and their interactions.

Table 4.

Summary of ANOVA statistical results.

Source of variation	SS	df	MS	F	p-Value	F crit
Conventional yarn/ conventional yarn
Between responses	64,686.06	4	16,171.52	13,928.73	1.7E-75	2.557179
Within responses	58.05095	50	1.161019
Total	64,744.12	54
Compact yarn/compact yarn
Between responses	65,052.38	4	16,263.09	16,282.62	3.44E-77	2.557179
Within responses	49.94004	50	0.998801
Total	65,102.32	54
Conventional yarn/compact yarn
Between responses	64,538.49	4	16,134.62	16,124.08	4.39E-77	2.557179
Within responses	50.0327	50	1.000654
Total	64,588.53	54

Conclusion

This study consisted of the production of 11 weave structures and the fabrics were divided into four groups on the basis of weave parameters CFF and FFF. Plain, 2/2 twill, 4/4 twill, 2/2 pointed twill, 8 thread twilled hopsack, 8 thread weft sateen, 8 thread honey comb, 8 thread Brighton honey comb, 8 thread Huck-a-back, 8 thread crepe cord and 8 thread pin head crepe were used from these three combinations. Essential parameters, namely, CFF, FYF, FFF, weave factor (P1), and the geometrical properties thickness, porosity and areal density were determined and the fabrics were tested for air resistance. The fabrics were divided into four groups on the basis of weave parameters CFF and FFF. Lower values of CFF and FFF are associated with longer floats. The weave parameters CFF, FYF and FFF are significantly correlated to the air resistance of the fabrics. Fabrics with longer floats have lower air resistance in comparison to those having shorter floats and no floats at all, namely, the plain weave. It is found that the thickness and porosity also are strongly correlated with air resistance. Only in conventional/conventional and conventional/compact cases are the correlations are significant. Thus it is suggested that in addition to the weave parameters, namely, CFF, FYF and FFF, thickness and porosity should also be taken into consideration for designing air bag, filtration and agri tex fabrics.