the preferred embodiments will be described with reference to the drawing figures wherein like numerals represent like elements throughout . referring to fig1 it shows a portion of the base fabric seam loops with additional threads woven in accordance with the present invention . the base fabric 1 comprises a top layer of md longitudinal threads , 10 , 12 , 14 , 16 , 18 , 20 , 22 , and 24 , and a bottom layer of md longitudinal threads , 11 , 13 , 15 , 17 , 19 , 21 , 23 and 25 . it will be understood that the top and bottom layers are essentially continuous threads which form the seam loops 35 - 1 to 35 - 8 between the top and bottom layers . typically , the phantom cmd threads 2 - 5 are interwoven with the top and bottom md longitudinal threads in a given repeat pattern to form the body of the fabric . the weave of the body of the fabric forms no part of the present invention . a seam zone 40 exists between the final cmd thread 2 and the seam loops 35 - 1 to 35 - 8 . reference is now made to fig3 and 5 . although some benefits will be obtained with a single additional thread , the preferred embodiments employ two additional threads for more uniformity in the paper side surface . the two additional cmd threads 50 and 51 are interwoven in the seam zone 40 with both layers of md threads 10 through 25 . additional cmd thread 50 preferably weaves in a repeat pattern that passes over md threads 10 - 11 , between md thread pairs 12 - 13 , 14 - 15 , 16 - 17 , 18 - 19 , 20 - 21 , over threads 22 - 23 and under md threads 24 - 25 . with reference to fig4 the second additional thread 51 is woven in a complementary pattern to that of the thread 50 . the cmd thread 51 weaves in a repeat that passes between thread pairs 10 - 11 , 12 - 13 , over threads 14 - 15 , under threads 16 - 17 , over threads 18 - 19 and between thread pair 20 - 21 , 22 - 23 , 24 - 25 . the complementary pattern of the repeats can be seen from fig5 . from fig5 it can be seen that the shifted weave repeats of threads 50 and 51 result in a transverse weave repeat that appears as a plain weave on the paper side surface of the fabric , and a mid - plane float between each md pair 10 - 11 , 12 - 13 , 14 - 15 , 16 - 17 , 18 - 19 , 20 - 21 , 22 - 23 , and 24 - 25 of the repeat . finally , these weave repeats result in minimum interlacings on the machine side of the fabric . this allows the mid - plane floats to migrate relative to one another , thereby effectively creating a virtually continuous mid - plane float across the width of the fabric , see fig6 . this is particularly beneficial in two - layer fabric constructions . with reference to fig7 and 9 , there is shown a second embodiment of the present invention . in this embodiment , the transverse additional thread 55 weaves between md threads 10 - 11 , under md threads 12 - 13 , between md threads 14 - 15 , over md threads 16 - 17 , between md thread pairs 18 - 19 , 20 - 21 , 22 - 23 and over md threads 24 - 25 . the additional transverse thread 56 weaves in a complementary pattern . thread 56 weaves over md threads 10 - 11 , between md thread pairs 12 - 13 , 14 - 15 , 16 - 17 , over md threads 18 - 19 , between md threads 20 - 21 , under md threads 22 - 23 , and between md threads 24 - 25 . as can be seen from fig9 these complementary weave patterns produce a sheet side weave pattern with pairs of transverse weave knuckles alternating with pairs of md threads that are over both of the additional transverse threads 55 and 56 . in addition to producing long continuous mid - plane floats , these patterns also increase the thread &# 39 ; s transition length as it passes from layer to layer . here , the threads 55 and 56 transition under three sheet side md threads while passing under only one machine side md thread . this embodiment provides minimum machine side surface interlacings , and long transitions that appear to provide a continuous a mid - plane float between six of the eight md pairs . a third embodiment of the present invention is shown in fig1 - 12 . the fabric of this embodiment repeats on twenty four md threads 10 - 33 . the two additional threads 70 and 71 are interwoven in the seam zone 40 with both layers of longitudinal threads 10 through 33 . additional cmd thread 70 weaves in a repeat pattern that passes between md threads 10 - 11 , under md threads 12 - 13 , between md thread pairs 14 - 15 , 16 - 17 , and then weaves a continuous portion of plain weave with top layer md threads 18 , 20 , 22 , 24 , 26 , 28 , 30 before transitioning down between md threads 32 - 33 . with reference to fig1 , the second additional thread 71 is woven in a complementary pattern to that of thread 70 . additional thread 71 weaves a plain weave construction with top layer threads 10 , 12 , 14 before transitioning into a mid - plane float between md thread pairs 16 - 17 , 18 - 19 , 20 - 21 , 22 - 23 weaving under md threads 24 - 25 and transitioning back to a mid - plane float between thread pairs 26 - 27 , 28 - 29 , 30 - 31 , 32 - 33 . as can be seen from fig1 , two additional threads interwoven in accordance with fig1 and 11 produce a weave repeat structure having the appearance of a plain weave in the upper layer and two crossover points 73 and 74 which are spaced apart by at least three md threads . this results from the additional longitudinal thread being in a continuous portion 80 of the weave repeat with seven adjacent md threads between transitions from the machine or paper side longitudinal threads . since the repeat pattern extends over twelve pairs of md threads with only a single interlacing in the machine side md layer and the additional threads can shift relative to each other , threads 70 and 71 tend to act as one thread in a continuous plain weave on the top layer . as a result of the long transitions and the interlacing patterns , the additional threads can migrate relative to each other to produce the desired sheet side weave pattern while also providing mid - plane floats and long transitions . the combined threads provide two mid - plane floats , each floating between five of six md thread pairs . with reference to fig1 - 15 , there is shown a fourth embodiment of the present invention . in this fourth embodiment , the first additional thread 75 weaves between md thread pairs 10 - 11 , 12 - 13 , beneath md threads 14 - 15 , between md thread pairs 16 - 17 , 18 - 19 , 20 - 21 , and then in a plain weave repeat with the upper layer md threads 24 , 26 , 28 , 30 , 32 . the second additional thread 76 weaves in the mirror image of thread 75 . as shown by fig1 , the threads 75 and 76 produce a plain weave pattern on the paper sheet side , relatively long transitions which combine in a virtual mid - plane float and widely spaced crossover points 77 , 78 which encourage migration of the threads relative to each other . as with the prior embodiment , this embodiment provides a continuous portion 81 of the weave repeat that extends over at least five adjacent paper side longitudinal threads between transitions from the machine or paper side longitudinal threads and two mid - plane floats , each floating between five of six md thread pairs . referring to fig1 - 18 , a fifth embodiment is shown . additional cmd thread 100 weaves in a repeat pattern that passes between md threads 10 - 11 , under md threads 12 - 13 , between md thread pairs 14 - 15 , 16 - 17 , floats over md threads 18 - 23 , between md threads 24 - 25 , floats over md threads 26 - 31 and between md threads 32 - 33 . with reference to fig1 , the second additional thread 101 is woven in a complementary weave pattern to that of thread 100 . additional thread 101 weaves over md threads 10 - 15 , between md thread pairs 16 - 17 , 18 - 19 , 20 - 21 , 22 - 23 , under md threads 24 - 25 and between md thread pairs 26 - 27 , 28 - 29 , 30 - 31 , 32 - 33 . it will be noted from fig1 that additional thread 101 forms two mid - plane floats between four pairs of md threads 16 - 17 , 18 - 19 , 20 - 21 , 22 - 23 and 26 - 27 , 28 - 29 , 30 - 31 , 32 - 33 . as can be seen from fig1 , the two additional threads 100 , 101 as interwoven in fig1 and 17 produce a weave repeat structure having the appearance of an over three , under one repeat in the upper layer . the two crossover points , 103 , 104 are spaced apart by at least three md threads . this creates a long continuous portion of the second additional thread 101 which generally forms mid - plane floats that complement the long transition of the first additional thread 100 . since the repeat pattern extends over twelve pairs of md threads with only a single interlacing in the machine side md layer and the additional threads can shift relative to each other , threads 100 and 101 tend to act as one thread in a continuous over three , under one weave pattern on the top layer . with reference again to fig1 and additional thread 100 , it can be seen that the weave repeat of thread 100 includes a subrepeat of over three , under one which repeats twice within the pattern . this weave repeat permits the relatively loose interlacing of the thread 101 but enables the pattern to be continued throughout the upper layer when the threads 100 , 101 are combined in accordance with fig1 . again , the combined threads 100 , 101 provide two mid - plane floats , each floating between five of six md thread pairs . with reference to fig1 - 21 , there is shown a sixth embodiment of the present invention . in this sixth embodiment , the first additional thread 105 weaves between md thread pairs 10 - 11 , 12 - 13 , beneath md threads 14 - 15 , between md thread pairs 16 - 17 , 18 - 19 , 20 - 21 and then in two repeats of the subrepeat pattern of over two , under one with upper md threads 22 , 24 , 26 , 28 , 30 , 32 . the second additional thread 106 weaves in the mirror image of thread 105 . as shown by fig2 , the threads 105 and 106 produce an over two , under one weave pattern on the paper sheet side , relatively long transitions in virtual five thread mid - plane floats and crossover points 107 , 108 which encourage migration of the threads relative to each other . as with the prior embodiment , this embodiment provides a weave repeat that includes two repeats of the subrepeat in adjacent paper side longitudinal threads between the transitions from the machine or paper side longitudinal threads . it will be appreciated that batt adhesion to the additional thread ( s ) of the various embodiments will be most improved on the sheet side surface but that improved machine side batt adhesion will be achieved . the additional cmd threads 50 , 51 , 55 , 56 ; 70 , 71 , 75 , 76 , 100 , 101 , and 105 , 106 can be multifilament , spun , braided , knitted , or bicomponent . if the thread is of a bicomponent nature , the bicomponent material may have a core material with a higher melting point surrounded by a covering of a lower melting point material . this allows the covering to melt and adhere to the batt material during finishing without affecting the core structure of the thread . threads may be made from polymeric resins selected from a group consisting of polyamide , polyurethanes , polyesters , polyaramids , polyimides , polyolefins , polyetherketones , polypropylenes , pet , pbt , ptt , phenolics , and copolymers thereof .